CRUISE REPORT: I01
(Updated JUN 2008)

A.  HIGHLIGHTS

A.1.  CRUISE SUMMARY INFORMATION

      WOCE section designation  I01
        Expedition designation  316N145_11-12 
              Chief Scientists  Dr. John M. Morrison/NCSU  (Leg 1)
                                Dr. Harry L. Bryden/SOC    (Leg 2)
                         Dates  1995 AUG  29 - 1995 SEP 28 (Leg 1)
                                1995 SEP  30 - 1995 OCT 16 (Leg 2)
                          Ship  R/V KNORR
                 Ports of call  Muscat, Oman to Columbo, Sri Lanka (Leg 1)
                                Columbo, Sri Lanka to Singapore    (Leg 2)

                                             22° 28.17 N
 Station geographic boundaries  43°  41.67 W             97° 33' E
                                              4° 0.30' N

                                Stations  158
  Floats and drifters deployed  16 ALACE floats
Moorings deployed or recovered  0
          Contributing Authors  Sarah Zimmerman, Maggie Cook, Marshall Swartz


Chief Scientists Contact Information

                             Dr. John M. Morrison
   Dept. of Marine, Earth and Atmospheric Science • North Carolina State U.
        1125 Jordan Hall • Raleigh, North Carolina • 27695-8208 • USA
             Phone: 919-515-7449 • Email: John_Morrison@NCSU.EDU

                              Dr. Harry L. Bryden
  Southampton Oceanography Centre • Empress Dock • Southampton S014 3ZH • UK
  Ph: 44-1703-596436 • Fax: 44-1703-596204 • Email:  h.bryden@soc.soton.ac.uk



A.2  CRUISE SUMMARY

A.2.a  Geographic boundaries

Cruise Track 
The cruise went across the North Indian Ocean at a nominal latitude of 8°N.  
From Muscat, the ship headed for the entrance to the Red Sea before starting 
the main section off the coast of Somalia.  The section across the Arabian 
Sea ended on the continental shelf of India.  After a brief port stop in 
Colombo, the section was continued from the Sri Lankan continental shelf 
across the Bay of Bengal and ended on the Myanmar continental shelf.   

A.2.b  Number of Stations

A total of 158 hydrographic stations were taken during the cruise, which 
includes three test stations to check instrument performance.  A list of 
station positions including a brief chronology of notable events is in Table 1.

Sampling
On each hydrographic station, a continuous CTD profile of temperature, 
salinity and oxygen versus pressure is measured throughout the water column 
from the sea surface down to the ocean bottom; 36 water samples are then 
collected during the upcast and analysed in the laboratory for salinity, 
oxygen, nutrients (nitrate+nitrite, nitrite, silica and phosphate), 
chlorofluorocarbons (CFC-11, CFC-12), CO2 components (total CO2 and 
alkalinity); on selected stations water samples were collected for later 
analysis for helium, tritium, 14C, 13C and barium; finally, an LADCP was 
mounted on the CTD/Rosette frame on nearly every station to measure 
continuous profiles of horizontal velocity from the sea surface to the bottom 
and back to the sea surface.  While underway and on station, continuous 
measurements were made of bottom depth, surface currents by a ship-mounted 
ADCP instrument with associated P-code GPS navigation, and meteorological 
variables with the ship-mounted IMET system.

Equipment used aboard KNORR for the basic CTD/Rosette system was provided by 
both Woods Hole Oceanographic Institution CTD Operations Group, and the 
Scripps Institution of Oceanography's Shipboard Technical Services/Ocean Data 
Facility (SIO STS/ODF).  Four CTDs were brought for the cruise, two of which 
were used for the majority of the stations.  Underwater equipment included:

Primary Sensors: Two Falmouth Scientific (FSI) ICTDs with Sensormedics oxygen 
sensors.  Each has a Sensormedics oxygen sensor assembly and a titanium 
pressure transducer with temperature monitor.

Secondary Sensors: Two Neil Brown Mk-3 CTDs.  Each has a Sensormedics oxygen 
sensor assembly and a titanium pressure transducer with temperature monitor.

In addition to the principal section across 8N-10N from Somalia to India, Sri 
Lanka to Myanmar, this station list contains:

1. a section along the axis of the Gulf of Aden
2. a meridional section across the Gulf of Aden from Yemen coastline
3. a section following German mooring line south of Socotra
4. a short section up onto the Sri Lanka continental shelf near Colombo
5. a short section south of the southern tip of Sri Lanka along 80°E to 
   4.5°N, repeating I8 stations 6 months later


Table 1:  Hydrographic Station Positions and Brief Chronology for WOCE 
          Section I1, R/V KNORR, 29 August to 16 October 1995, Muscat to 
          Singapore

          Sta   WOCE   Lat      Lon     Depth  Comments                CTD 
           #     #     (N)      (E)      (m)                           Used
          ---   ----  -------  -----    -----  ----------------------  -----
          Start       23 37    58 38           Muscat Dep 8/29 0600  
            1    857  22 28    61 12    3215   Station 841 on I7N      CTD38
            2    858  22 28    61 12    3190   and                     CTD09
            3    859  22 28    61 12    3190   JGOFS station           CTD44
            4    860  21 35    60 35           Water sample test 300m  
            5    861  19 05    58 48    3285   Station 808 on I7N  
            6    862  18 05    58 00    2815   JGOFS station  
            7    863  16 16    56 33    3710   CTD test                CTD09
            8    864  14 50    55 25    2440                           CTD12  
            9    865  14 40    54 45    2205                           CTD44  
           10    866  14 30    54 05    2595     
           11    867  14 20    53 25    2970   Terminated at 700db  
           12    868  14 20    53 25    2960   ALACE deployed  
           13    869  14 10    52 45    1880   Terminated at 500bd  
           14    870  14 10    52 45    1895                           CTD38
           15    871  14 00    52 10    2195     
           16    872  13 50    51 30    1790   Repeated as 35  
           17    873  12 22    43 42     300   Exit of Red Sea  
           18    874  12 10    44 00     495     
           19    875  12 00    44 30    1410     
           20    876  12 10    45 05     815     
           21    877  12 20    45 45    1390     
           22    878  12 30    46 25    1770     
           23    879  12 40    47 00    2005     
           24    880  12 50    47 40    2350     
           25    881  13 00    48 20    1995   ALACE deployment  
           26    882  13 10    48 55    2640     
           27    883  13 20    49 35    1950     
           28    884  13 30    50 15    1955     
           29    885  13 40    50 50    2470     
           30    886  14 55    50 50     190   Yemen Shelf  
           31    887  14 49    50 50     560     
           32    888  14 40    50 50    1230   ALACE deployment  
           33    889  14 30    50 50    1955     
           34    890  14 10    51 10    2200     
           35    891  13 50    51 30    1825     
           36    892  13 43    51 34    4000   Proceed around Socotra  
           37    893  10 48    53 22    3905   Pegasus German          CTD44
           38    894  10 34.2  53 26    4020   mooring K14  
           39    895  10 21    53 32    4185   Pegasus mooring  
           40    896  10 09.9  53 38    4280   mooring K15  
           41    897   9 54    53 48    4460   Pegasus line  
           42    898   9 38.1  53 56    4580   mooring K16  
           43    899   9 39    53 19    4580   Test station for        CTD12
 
 
          Sta   WOCE   Lat      Lon     Depth  Comments                CTD 
           #     #     (N)      (E)      (m)                           Used
          ---   ----  -------  -----    -----  ----------------------  -----
           43    900   9 42    51 30     760   Somalia                 CTD44
           44    901   9 35    51 40    1480   Fast ALACE deployment  
           45    902   9 28    51 50    2325     
           46    903   9 20    52 00    3650   Fast ALACE deployment  
           47    904   9 06    52 17    4540     
           48    905   8 48    52 41    4900   Fast ALACE deployment  
           49    906   8 30    53 05    5035     
           50    907   8 30    53 40    4970     
           51    908   8 30    54 15    5025   mooring K17 8 43,54 20  
           52    909   8 56    54 25    4800   Halfway between 908+909  
           53    910   8 30    54 50    4660     
           54    911   8 30    55 25    4730   Fast ALACE deployment  
           55    912   8 30    56 00    3800     
           56    913   8 30    56 35    4380     
           57    914   8 30    57 10    4385     
           58    915   8 30    57 34    3105     
           59    916   8 30    58 06    3905   Section  
           60    917   8 37    58 24    3700   Perpendicular to  
           61    918   8 42    58 37    2305   Carlsberg Ridge  
           62    919   8 51    59 00    3150   ALACE deployment  
           63    920   8 57    59 14    3525     
           64    921   9 01    59 25    3615     
           65    922   9 01    59 57    3540     
           66    923   9 01    60 29    3345     
           67    924   9 01    61 01    3965     
           68    925   9 01    61 33    4380     
           69    926   9 01    62 05    4530     
           70    927   9 01    62 37    4545   ALACE deployment  
           71    928   8 54    63 08    4535     
           72    929   8 48    63 34    4535   I7 station 782  
           73    930   8 42    64 00    4530     
           74    931   8 36    64 26    4560     
           75    932   8 30    64 52    4550     
           76    933   8 30    65 23    4535     
           77    934   8 30    65 53    4525   ALACE deployment  
           78    935   8 30    66 23    4530     
           79    936   8 30    66 53    4555     
           80    937   8 30    67 23    4560     
           81    938   8 30    67 53    4575     
           82    939   8 30    68 23    4575     
           83    940   8 30    68 54    4590   ALACE deployment  
           84    941   8 30    69 25    4615   Pick up Indian Officer  
           85    942   8 30    70 00    4465     
           86    943   8 30    70 35    4165     
           87    944   8 30    71 10    3910     
           87    945   8 30    71 45    3475     
           88    946   8 30    72 05.7  2685   ALACE deployment  


          Sta   WOCE   Lat      Lon     Depth  Comments                CTD 
           #     #     (N)      (E)      (m)                           Used
          ---   ----  -------  -----    -----  ----------------------  -----
           89    947   8 30    72 26    2125    
           90    948   8 30    72 47    2190    
           91    949   8 30    73 08    2250    
           92    950   8 30    73 28    1910    
           93    951   8 34    73 50    2650    
           94    952   8 39    74 15    2750    
           95    953   8 44    74 40    2750    
           96    954   8 48    75 00    2695    
           97    955   8 52    75 20    1665    
           98    956   8 56    75 40     345    
           99    957   9 00    76 00      95    
          Way    012   6 58    78 25           Disembark Indian Off  
          100    958   6 25    79 06    2685   Baldridge station  
          101    959   6 33    79 18    2345   Baldridge station  
          102    960   6 42    79 30    1630   Baldridge station  
          103    961   6 48    79 36     705   Baldridge station  
           Colombo     6 55    79 52           Colombo Arr 9/28 0500  
           Colombo     6 55    79 52           Colombo Dep 9/30 0300  
          104    962   5 53    80 00     155   Short Section  
          105    963   5 49    80 00    1110   Across Boundary  
          106    964   5 45    80 00    2215   Current South of  
          107    965   5 40    80 00    3235   Sri Lanka  
          108    966   5 35    80 00    4030   I8 Station 284  
          109    967   5 15    80 00    4135   Along 80 E  
          110    968   4 55    80 00    4225   ALACE in 6C mode water  
          111    969   4 30    80 00    4285   Down to 4.5°N  
          112    970   8 31    81 28      55     
          113    971   8 37    81 36    2695     
          114    972   8 46    81 48    3740   ALACE deployed  
          115    973   8 58    82 04    3750                           CTD38
          116    974   9 13    82 24    3730                           CTD44
          117    975   9 28    82 44    3695                           
          118    976   9 43    83 04    3650                           
          119    977   9 58    83 24    3620                           
          120    978   9 58    83 51    3610                           CTD38
          121    979   9 58    84 18    3580   ALACE deployed          CTD44
          122    980   9 58    84 45    3570                           CTD38
          123    981   9 58    85 12    3565     
          124    982   9 13    82 24    3725   Redo 974  
          125    983   9 28    82 44    3695   Redo 975  
          126    984   9 43    83 04    3645   Redo 976  
          127    985   9 58    84 18    3585   Redo 979  
          128    986   9 58    85 39    3540     
          129    987   9 58    86 12    3505     
          130    988   9 58    86 45    3495     
          131    989   9 50    86 47    3510   I9 station 268  
          132    990   9 58    87 18    3480    
          


          Sta   WOCE   Lat      Lon     Depth  Comments                CTD 
           #     #     (N)      (E)      (m)                           Used
          ---   ----  -------  -----    -----  ----------------------  -----
          133    991   9 58    87 51    3425   ALACE  
          134    992   9 58    88 24    3405     
          135    993   9 58    88 57    3375     
          136    994   9 58    89 28    3350     
          137    995   9 58    89 59    3310     
          138    996   9 58    90 30    3330   Pick up Ind. Navy Off  
          139    997   9 58    91 00    3470   I9 station 234  
          140    998   9 58    91 27    3405     
          141    999   9 58    91 54    1285     
          142   1000   9 58    92 16     845     
          143   1001   9 58    92 38     990   Ten Degree Channel  
          144   1002   9 58    93 00    1435     
          145   1003   9 58    93 22    3065     
          146   1004   9 58    93 46    4235     
          147   1005   9 58    94 12    3180     
          148   1006   9 58    94 38    2855     
          149   1007   9 54    95 04    1775   Disembark Indian Off  
          150   1008   9 50    95 30    2620     
          151   1009   9 50    95 50    2475     
          152   1010   9 50    96 10    1315     
          153   1011   9 50    96 30     430     
          154   1012   9 50    96 55     325     
          155   1013   9 50    97 17     260     
          156   1014   9 50    97 33      83     
          End          1 20   103 50           Singapore Arr10/15 1100  


General Oceanics (GO) model 1016-36 pylon with 36-bottle frame with 10-liter 
bottles manufactured by SIO STS/ODF and Ocean Instrument Systems 10-kHz 
pinger.   


A.2.c.  Floats:  ALACE Deployments

Autonomous Lagrangian Circulation Explorer (ALACE) floats are intended to map 
absolute velocity of large-scale currents for use with geostrophic shears 
from historical and WOCE Hydrographic Programme sampling.  The floats drift 
at 800 to 1000 m depth, surfacing periodically to report their position by 
satellite.  To avoid diffusion bias, the horizontal coverage is intended to 
be relatively uniform but the density for this cruise was augmented a bit 
near the western boundary of the Somalia coast

Two floats could not be launched as planned because they were in the 
territorial waters of India.  Permission for such deployments had not been 
requested from the Government of India and the official Indian observer 
insisted that no ALACE deployments were allowed.  One of the resulting two 
extra floats was deployed in a thermostad feature south of Sir Lanka at about 
1000 m depth at 4 44 N, 80 E.  Most of the ALACE floats have a 26-day cycle 
time, drifting for 26 days at 800 to 1000 m depth, then rising to the sea 
surface to report position to a satellite, before returning to depth to 
repeat the cycle for another 26 days.  Design lifetime for these floats is 5 
years.  Four of the ALACE floats deployed in the region of the Somali Current 
(denoted by "F") have 15-day cycle times.  Each ALACE float was prepared in 
the laboratory during the downcast of a CTD station and launched from the 
stern of KNORR at the completion of a hydrographic station just as the ship 
set out for the next station. The launch information is shown in Table 2.


TABLE 2:  WOCE I1 ALACE FLOAT LAUNCH INFORMATION

          S/N   START TIME OF   DEPLOYMENT        DEPLOYMENT 
                LAST SELFTEST      TIME            POSITION
          ----  -------------  ------------  --------------------
          536   950903 0230Z   950903 0357Z  14:20.03N, 53:25.11E
          534   950907 0413Z   950907 0557Z  13:00.34N, 48:19.81E
          539   950908 0912Z   950908 1302Z  14:38,08N, 50:49.52E
          523F  950912 0944Z   950912 1126Z  09:36,95N, 51:40.11E
          521F  950912 1547Z   950912 1944Z  09:21.39N, 51:58.86E
          522F  950913 0527Z   950913 0857Z  08:50.95N, 52:41.39E

          524F  950914 1555Z   950915 0234Z  08:27.02N, 55:24.39E
          540   950916 1452Z   950916 2328Z  09:49.95N, 59:00.22E
          546   950918 2142Z   950919 0148Z  09:00.87N, 62:36.73E
          545   950921 0131Z   950921 0323Z  08:29.95N, 65:53.15E
          542   950922 1955Z   950922 2217Z  08:29.80E, 68:53.85E
          541   950924 0841Z   950924 1022Z  08:30.14N, 72:04.99E
          543   951001 1615Z   951001 1940Z  04:55.10N, 79:59.93E
          544   951003 0318Z   951003 0530Z  08:35.22N, 81:36.64E
          533   951005 0413Z   951005 0626Z  09:58.81N, 84:17.46E
          532   951008 2001Z   951008 2206Z  09:58.18N, 87:51.67E


A.2.d  Mooring deployed or recovered


A.3  LIST OF PRINCIPLE INVESTIGATORS

The list of Principal Investigators, their institution and the measurement 
program that they are responsible for is shown in Table 3.  


Table 3:  WOCE I1 Principal Investigators

Measurement               Principal         Institution
                          Investigator     
------------------------  ----------------  -------------------------------
Chief Scientist           John M. Morrison  North Carolina State Univ,
co-Chief Scientist        Harry Bryden      Southampton Oceanography Centre
Salinity, oxygen, CTD/O2  John Toole        Wood Hole Oceanographic Inst.
Nutrients                 Louis Gordon      Oregon State Univ.
Chlorofluorocarbons       Mark Warner       Univ. of Washington
Shallow He/Tr             William Jenkins   Wood Hole Oceanographic Inst.
Deep He/Tr                Zafer Top         Univ. of Miami
AMS C-14                  Robert Key        Princeton University
Barium                    Kelly Falkner     Oregon State University
TCO2                      Catherine Goyet   Wood Hole Oceanographic Inst.
ADCP/LADCP                Teresa Chereskin  Scripps Inst. of Oceanography    
Underway PCO2             Robert Key        Princeton Univ.
IMET                      Barrie Walden     Wood Hole Oceanographic Inst.
Thermosalinograph         Barrie Walden     Wood Hole Oceanographic Inst.
ALACE Floats              Russ Davis        Scripps Inst. of Oceanography


A.4  SCIENTIFIC PROGRAMME AND METHODS

The transindian hydrographic section I1 is the northernmost of the zonal 
sections to be carried out during the US WOCE Indian Ocean Expedition in 
1994-1996. It crosses the southern boundaries of both the Bay of Bengal in 
the east and the Arabian Sea in the west. This section effectively completes 
the circumnavigation of the ocean with high quality hydrographic sections at 
latitudes between 8°N and 11°N, started by the 10°N transpacific and the 11°N 
transatlantic section carried out in 1989.

Section I1 encloses two areas of the northern Indian Ocean, the Arabian Sea 
and the Bay of Bengal. From I1 we should be able to compute separate heat, 
salt and water-mass budgets for each of these basins. This is of interest 
because the Arabian Sea is an important source of salt to the world ocean, 
while the Bay of Bengal is an important source of fresh water. In addition to 
helping define the thermohaline circulation of the Indian Ocean in 
conjunction with the overall survey of the Indian Ocean Expedition, the 
specific objectives of the Principal Investigators (PIs) are: 

1.  To determine the meridional heat and freshwater transports across 8°N in 
    the Indian Ocean and to combine the new estimates with existing Atlantic 
    and Pacific estimates in order to determine the total global ocean heat 
    and freshwater transports across 10°N for comparison with the atmospheric 
    and satellite-based estimates of energy transport; 

2.  To make a detailed analysis of the freshwater budget of the Bay of 
    Bengal, into which 2 of the world's largest rivers empty, in order to 
    understand the effects of this freshwater source on the Indian Ocean 
    circulation; 

3.  To estimate the nutrient (and possibly the carbon transport) into and out 
    of the Arabian Sea across its southern boundary at 8°N in order to 
    estimate the size of the overall biological productivity and of the 
    "biological pump" in the Arabian Sea for comparison with JGOFS results. 

4.  To cooperate with the PIs of the other WOCE Indian Ocean Expedition on 
    the preparation of a new "atlas" describing the first order circulation 
    of the basin and to present and catalog the data collected in a 
    systematic fashion. 

5.  To coordinate the results of our survey with the JGOFS Arabian Sea 
    Process Study.  JGOFS is carrying out 7 cruises within the Arabian Sea, 
    encompassing an entire monsoonal cycle.  The JGOFS data will be used to 
    investigate the representativeness of the WOCE sections in the Arabian 
    Sea, where there is large seasonal variability associated with monsoonal 
    forcing.  In addition, comparison of data collected during the JGOFS 
    efforts near the mouth of the Arabian Sea with the hydrographic 
    properties at Section I1 may allow us to estimate the percentage of 
    Persian Gulf Water that actually escapes into the Indian Ocean. Finally, 
    estimates of the amount of Arabian Sea Water leaving the basin at the end 
    of the Southwest Monsoon will be made. 

6.  To determine the extent of eastward penetration of high salinity Arabian 
    Sea waters during the boreal winter that displace the low salinity waters 
    normally carried westward by the North Equatorial Current (NEC).

7.  To describe the deep water properties of the Adaman Basin, which is an 
    enclosed basin below approximately 1500 m depth.

In addition, there are a number of questions that will be addressed using 
data from a combination of multiple sections, VOS XBT data, Lagrangian 
drifter data, etc. We will actively share the I1 measurements with other 
scientists working on such objectives and questions. 
Preliminary Results

KNORR departed Muscat, Oman, on schedule on 29 August 1995.  We proceeded 
westward down the coast of Oman, reoccupying a joint JGOFS and I7 station 
(841) at 22° 28' N, 61° 12' E,  an I7 station (808) at 19° 05' N, 58° 48' E 
and a JGOFS station at 18° 05' N, 58° 00' E.  Preliminary inter-comparisons 
of the data show excellent agreement.  We then proceeded to carry out our 
Gulf of Aden Section.  This section has 20 stations along a line from 12° 
22' N, 43° 44' E to  14° 50' N, 55° 22' E.  This section shows considerable 
variability, but gives us a good endpoint for Red Sea Water for water mass 
analysis.  Satellite imagery from the JGOFS receiving station in Oman will 
aid in interpreting this data.

Because of the threat of pirates, we were forced to cancel the southern half 
of our planned section across the mouth of the Gulf of Aden.  Instead, we 
proceeded to the position of a German current meter array south of Socotra.  
Once again because of the threat of pirates, we were forced to cancel any 
work around the moorings within 60 nm of Socotra.  In discussions with Dr. F. 
Schott via Imarsat, we determined that we were just ahead of METEOR on this 
section.  We coordinated our efforts with Schott to make a more densely 
spaced section along his array.  In addition, we occupied 3 of his Pegasus 
sites for intercomparison of our LADCP velocities with his Pegasus velocity 
profiles.

We then proceeded to 9° 42' N, 51° 30' E to begin the main I1 line across the 
Arabian Sea.  We took 6 closely spaced stations across the Somali Current, 
angling down to our main section latitude of 8° 30' N. The main section is 
across the basin at 8° 30' N, except for a short diagonal section 
perpendicular to the Carlsberg Ridge at about 58° E and a diversion to 
reoccupy another I7 station (782) at 8° 48' N, 63° 54'E.

On Monday, 18 September, we received word that the Government of India has 
decided to give a one-time exemption to carry out work in their waters at 20 
nm spacing and to allow use of the ADCP and LADCP.  Fortunately, the State 
Department and WOCE Office had been able to give us a heads-up on the 
clearance about a week earlier.  We picked up the Indian Observer at 8° 30' 
N, 69° 25' E on Saturday, 23 September.  We then continued our line through 
the Laccadive Islands at the 8 Degree Channel and into the coast at 9° 00' N, 
76° 00' E.  In all we took 58 stations along the main I1 section of which 17 
stations were within the Indian EEZ.  

From the end of the main section, we disembarked the Indian Observer while 
transiting to Sri Lankan waters.  We then reoccupied the 4 inshore stations 
of the BALDRIDGE I1 Pre- peat section onto the Sri Lankan shelf.  We arrived 
in Colombo, Sri Lanka, on the morning of 28 September, having completed 103 
stations on Leg 1.  The final station on this leg was WOCE station 961.

KNORR departed Colombo, Sri Lanka, on schedule at 0800 on 30 September 1995 
and proceeded south of Sri Lanka where 8 stations of Section I8 was 
reoccupied along 80° E to 4° 30' N.  Currents were weak along this section, 
showing little sign of the Indian Monsoon Current.  Time had been scheduled 
time to occupy 2 stations in the Trincomalee Canyon at about 8° 30' N, 81° 
20' E on the coast of Sri Lanka at the request of Kamal Tennakoon of National 
Aquatic Resources Agency in Sri Lanka. The Sri Lankan Naval Observer 
informed us that the Tamal Tigers were active in this area and advised us not 
to take these stations.  KNORR then proceeded to the endpoint of the main 
line at 8° 31' N , 81° 28' E (just off the coast of Sri Lanka).  Even though 
this station was in sight of land in the vicinity of the city of Trincomalee 
(where there is a major Sri Lankan Naval Base), the Sri Lankan Navy was so 
concerned about the potential threat of the Tamal Tigers, that they requested 
that we occupy this station during the daylight hours.  They also escorted us 
with 4 gunboats as we came up the coast from the south to the location of 
this station.  KNORR began the main line across the Bay of Bengal without 
incident.  The first 8 stations were along a SW to NE line from the coast of 
Sri Lanka to the latitude of the proposed section, 9° 58' N, across the Bay 
of Bengal. As KNORR proceeded along the main line, a 2 - 3 knot current 
flowing to the south out to about 75 nm (at least to the 4000 m isobath) was 
observed in the shipboard ADCP record.  We then proceeded along the main line 
to 9° 58' N, 85° 12' E, where a problem with the CTD occurred.  Fortunately, 
we had been processing the data with about a 24 hour delay.  Because we had 
time, we decided to backtrack and redo 4 of the stations along the main line.  
We proceeded back to 9° 58' N, 85° 12' E, and continued to the east along 
the main line.  We diverted slightly off the main line to reoccupy I9 Station 
268.  We picked up the Indian Naval Observer at 9° 58' N, 88° 58' E on Monday 
morning, 9 October 1995. We then proceeded with our section across the Adaman 
Sea.  The Indian observer disembarked just prior to our entry into the waters 
of Myanmar.  The last 4 stations of the line were within the waters of 
Myanmar.  We completed the section at station 1014 and deadheaded to 
Singapore, anchoring in the harbour for the night of 15 October 1995 before 
docking on 16 October.


A.5  MAJOR PROBLEMS ENCOUNTERED ON THE CRUISE

Because of the threat of pirates, we were forced to cancel the southern half of 
our planned section across the mouth of the Gulf of Aden.  Also, because of the 
threat of pirates, we were forced to cancel any work around the German current 
meter moorings within 60 nm of Socotra. Finally, because of the threat of 
pirates we were not able to begin the section as close to Somalia as we would 
have liked; our most inshore station was in about 850 meters of water; the ADCP 
data shows that the most inshore hydrographic station was in the core of the 
Somali Current; hence we were not able to sample completely across to the 
inshore side of the Somali Current.

Potential problem with Standard Seawater Batch P-124.
Suspicion that salinity samples drawn after long times on deck might be 
changed due to condensation in the warm moist air in the head space of cold, 
deep-water bottles.

LADCP equipment failure for a section of the first leg leaves a portion of 
the section across the mouth of the Arabian Sea without absolute velocities.  


A.6  OTHER OBSERVATIONS OF NOTE

Preliminary data were supplied to the foreign observers of India, Sri Lanka 
and Myanmar prior to their departure from the ship.  


A.7  LIST OF CRUISE PARTICIPANTS

Crew List                                    Leg 1           Leg 2
-----------------------------------------    ---------       ---------
1.  Dr. John Morrison, Co-Chief Scientist    CTD Watch       CTD Watch
North Carolina State University 
MEAS Box 8208 
Raleigh, NC 27695-8208 
U. S. Citizen 
Ph:    (919) 515-7449 
Fax:   (919) 515-7802 
Email: John_Morrison@ncsu.edu 
(PI:   Morrison) 
 
2.  Vijayakumar Manghnani                    CTD Watch       CTD Watch
North Carolina State University 
MEAS Box 8208 
Raleigh, NC 27695-8208 
Ph:    (919) 515-7449 
Fax:   (919) 515-7802 
Email: vijay@meadsp.nrrc.ncsu.edu 
(PI:   Morrison) 

3a.  L. V. Gangadhara Rao                                    CTD Watch 
Physical Oceanography Division 
National Institute of Oceanography 
Dona Paula, Goa - 403 004, India 
Indian Citizen 
Ph:    91-832-226253 - 56 (O) 
       91-832-221848 (R) 
Fax:   91-832-223340 
Email: lvgrao@bcgoa.ernet.in 
Telex: 0194-216 NIO IN 
(PI:   Morrison) 
 
3b.  M. T. Babu                              CTD Watch 
Physical Oceanography Division  
National Institute of Oceanography 
Dona Paula, Goa - 403 004, India 
Indian Citizen 
Ph:    91-832-221323 
Fax:   91-832-223340 
Email:     
(PI:   Morrison) 
 
4.  Dr. Harry L. Bryden, Co-Chief Scientist  CTD Watch       CTD Watch
Southampton Oceanography Centre 
Empress Dock 
Southampton S014 3ZH, UK 
U. S. Citizen 
Ph:    44-1703-596436 
Fax:   44-1703-596204 
Email: h.bryden@soc.soton.ac.uk 
(PI:   Bryden) 
 
5a.  Lisa M. Beal                            CTD Watch 
Southampton Oceanography Centre 
Empress Dock 
Southampton S014 3ZH, UK 
U. K. Citizen 
Ph:    44-1703-596436 
Fax:   44-1703-596204 
Email: lmb@soc.soton.ac.uk 
(PI:   Bryden) 
 
5b.  Dr. Michael N. Tsimplis                                 CTD Watch
Southampton Oceanography Centre 
Empress Dock 
Southampton S014 3ZH, UK 
Greek Citizen 
Ph:    44-1703-596441 
Fax:   44-1703-596204 
Email: mnt@soc.soton.ac.uk 
(PI:   Bryden) 
 
6a.  Alison Scoon                            CTD Watch 
26a Gibbon Road 
Kingston Upon Thames 
KT2 6AB, UK 
Ph:       0181 5415025 
or  
Southampton Oceanography Centre 
Empress Dock 
Southampton S014 3ZH, UK 
c/o Ian Robinson 
 
6b.  Michael J. Griffiths                                    CTD Watch
Southampton Oceanography Centre 
Empress Dock 
Southampton S014 3ZH, UK 
U. K. Citizen 
Ph:    44-1703-596436 
Fax:   44-1703-596204 
Email: m.griffiths@soc.soton.ac.uk 
(PI:   Bryden) 
 
7.  Craig Harris                             CTD Watch       CTD Watch
Oceanography Laboratories 
Department of Earth Sciences 
Liverpool University 
Liverpool L693BX, UK  
U. K. Citizen 
Ph:    44-151-7944097 
Email: 
(PI:   Bryden) 
 
Crew List       Leg 1       Leg 
8.  Marshall Swartz                          CTD W Leader    CTD W Leader
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-2246   
Fax:   (508) 457-2165 
Email: mswartz@whoi.edu 
(PI:   Toole) 
      
9.  Paul Robbins                             CTD W Leader    CTD W Leader
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-2918   
Fax:   (508) 457-2181 
Email: probbins@whoi.edu 
(PI:   Toole) 
 
10.  Laura Goepfert                          CTD Data Anal   CTD Data Anal
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-2937 
Fax:   (508) 457-2165 
Email: lgoepfert@whoi.edu 
(PI:   Toole) 
 
11.  Paul Bouchard                           CTD Watch       CTD Watch
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-3277   
Fax:   (508) 457-2165 
Email: pbouchard@whoi.edu 
(PI:   Toole) 
 
12.  George Tupper                           Salts           Salts
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-2693   
Fax:   (508) 457-2165 
Email: gtupper@whoi.edu 
(PI:   Toole) 
 
13.  Dave Wellwood                           Dissolved Oxys  Dissolved Oxys
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-2657 
Fax:   (508) 457-2165 
Email: dwellwood@whoi.edu 
(PI:   Toole) 
 
Crew List       Leg 1       Leg 2
14.  Joe C. Jennings, Jr.                    Nutrients       Nutrients
Oregon State University 
U. S. Citizen 
Ph:    (503) 737-4365 
Fax:   (503) 737-2064 
Email: jenningj@oce.orst.edu 
(PI:   Gordon) 
 
15.  Stanley Moore, Jr.                      Nutrients       Nutrients
Oregon State University 
U. S. Citizen 
Ph:    (503) 737-3961 
Fax:   (503)737-2064 
Email: moores@ucs.orst.edu 
(PI:   Gordon) 
 
16.  Greg Eischeid                           CO2             CO2
Woods Hole Oceanographic Institution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-3410 
Fax:   (508) 289-2193 
Email: geischeid@whoi.edu 
(PI:   Goyet) 
 
17.  Philip Ording                           CO2             CO2
Woods Hole Oceanographic Institution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 457-2000-3553 
Fax:   (508) 289-2193 
Email: cathy@co2.whoi.edu 
(PI:   Goyet) 
 
18.  Toshitaka Amaoka                        CO2             CO2
Marine and Atmospheric Geochemistry 
Graduate School of Environmental Earth Science 
Hokkaido University 
Sapporo 060, Japan 
Japanese Citizen 
Ph:    81-11-706-2371 
Fax:   81-11-726-6234 
Email: f063411@eoas.hokudai.ac.jp 
(PI:   Goyet) 
 
19. Kozo Okuda                               CO2             CO2
Marine and Atmospheric Geochemistry 
Graduate School of Environmental Earth Science 
Hokkaido University 
Sapporo 060, Japan  
Japanese Citizen 
Ph:    81-11-706-2371 
Fax:   81-11-726-6234 
Email: f053305@eoas.hokudai.ac.jp 
(PI:   Goyet) 
 
20a.  Teri Chereskin                         ADCP/LADCP 
Scripps Institute of Oceanography 
Mail Code 0230 
9500 Gilman Drive 
La Jolla, CA 92093-0230 
U. S. Citizen 
Ph:    (619) 543-6368 
Fax: 
Email: teri@scafell.ucsd.edu 
(PI:   Chereskin) 
 
20b.  Matthew Trunnell                       ADCP/LADCP 
Scripps Institute of Oceanography 
Mail Code 0230 
9500 Gilman Drive 
La Jolla, CA 92093-0230 
U. S. Citizen 
Ph:    (619) 543-5996 
Fax:   (619) 534-0704 
Email: matter@ucsd.edu 
(PI:   Chereskin) 
 
21.  Peter Landry                            He/Tr           He/Tr
Woods Hole Oceanographic Insitution 
Woods Hole, MA 02543 
U. S. Citizen 
Ph:    (508) 289-2918   
Fax:   (508) 457-2000-2165 
Email: plandry@whoi.edu 
(PI:   Jenkins) 
 
22.  Murat Aydin                             Deep He         Deep He
c/o Zafer Top 
RSMAS 
Univ of Miami 
4600 Rickenbaker Causeway 
Miami, FL 33149 
Turkish Citizen 
Ph:    (305) 361-4110 
Fax:   (305) 361-4112 
Email: maydin@rsmas.miami.edu 
(PI:   Top) 
 
23.  Steven Covey                            CFC             CFC
University of Washington 
School of Oceanography 
Box 357940 
Seattle, WA 98195-7940 
U. S. Citizen 
Ph:    (206) 543-5059 
Email: scovey@ocean.washington.edu 
(PI:   Warner) 

24a.  Sabine Mecking                         CFC 
University of Washington 
School of Oceanography 
Box 357940 
Seattle, WA 98195-7940 
German Citizen 
Email: mecking@ocean.washington.edu 
(PI:   Warner) 
 
24b.  Welin Huang                            CFC 
University of Washington 
School of Oceanography 
Box 357940 
Seattle, WA 98195-7940 
Email:  mwarner@ocean.washington.edu 
(PI:    Warner) 
 
25.  Richard Rotter                          C14             C14
Princeton University 
U. S. Citizen 
Ph:    (609) 258-3222 
Fax:   (609) 258-1274 
Email: rotter@wiggler.princeton.edu 
(PI:   Key) 
 
26a.  CDR M. Sarangapani                     Observer 
Oceanographic Forecasting Cell 
Headquarters 
Southern Naval Command 
Naval Base 
Cochin --- 682004 
India 
Ph:    0484-662472 (O) 
       0484-662815 (R) 
(Indian Observer) 
 
26b.  LCDR S. Murali                                         Observer
Indian Navy 
Met Officer 
INS JARAWA 
c/o Navy Office 
Port Blair 
(Observer) 
 
27a.  LCDR S. Jayakody                       Observer/CTD 
Naval Headquarters 
P. O. Box 593 
Colombo 
Sri Lanka 
Ph:    94-1-421151 
(Sri Lankan Observer) 
 
27b.  LCDR M.R.A.R.B. Mapa                   Observer/CTD 
Naval Headquarters 
P. O. Box 593 
Colombo 
Sri Lanka 
Ph:    94-1-421151 
Fax:   94-1-433896 
(Sri Lankan Observer) 
 
28.  Tilak Dharmaratne                       Observer/CO2 
Research Officer 
National Aquatic Resources Agency (NARA) 
Crow Island 
Colombo-15 
Sri Lanka 
Ph:    94-1-522932 
Fax:   94-1-522932 
(Sri Lankan Observer) 
 
29.  Dr. San Hla Thaw                        Observer/CTD 
Research Officer 
Department of Meteorology and Hydrology 
Yangon, Myanmar 
Ph:    95-1-65669 
Fax:   95-1-65944 
(Myanmar Observer) 
 
30.  Lt. Win Thein                           Observer/CTD 
Oceanographic Survey Officer 
Naval Hydrographic Office 
Myanmar Navy 
55/61 Strand Road 
Yangon 
Myanmar 
Ph:    95-1-95256 
(Myanmar Observer) 







_________________________________________________________________________________________________________
_________________________________________________________________________________________________________







OUTLINE OF DATA PROCESSING DOCUMENTATION

INTRODUCTION
DATA DOCUMENTATION
INSTRUMENT CONFIGURATION
ACQUISITION AND PROCESSING METHODS
SUMMARY OF LABORATORY CALIBRATIONS FOR CTDs
     PRESSURE CALIBRATIONS
          ICTD1338
          ICTD1344
          PRESSURE BIAS BY STATION NUMBER
TEMPERATURE CALIBRATIONS
          ICTD1338
          ICTD1344
SALINITY CALIBRATIONS
     Table 1 Conductivity coefficients by station number for all stations.
     SALINITY FITTING RESULTS
          Figure 1 Leg 1 CTD-bottle salts downtrace stns 878 to 981.
          Figure 2 Leg 2 CTD-bottle salts downtrace stns 982 to 999.
          Figure 3 Leg 1 CTD-bottle salts uptrace stns 878 to 981.
          Figure 4 Leg 2 CTD-bottle salts uptrace stns 982 to 999.
OXYGEN CALIBRATIONS
     SENSOR FAILURES
     OXYGEN DATA FITTING
          Table 2  Oxygen fitting coefficients for normal algorithm for all 
                   but 53 stations.
     SPECIAL ALGORITHM FITTING
          Figure 5  stn 865-869 bottle-CTD oxygen.
          Figure 6  stn 912-922 bottle-CTD oxygen.
          Figure 7  stn 912-922 CTD oxygen vs pressure.
          Figure 8  stn 930-933 CTD oxygen vs pressure.
          Table 3   Oxygen fitting coefficients for 53 stations using special 
                    algorithm.
          Figure 9  Leg 1 stations (857-961) CTD-bottle oxygen by station and 
                    by pressure.
          Figure 10 Leg 2 stations (962-999) CTD-bottle oxygen by station and 
                    by pressure.
          Figure 11 example of results of oxygen current digitizer change in 
                    CTD.
          Figure 12 stn 978 example of CTD oxygen data quality flag being 
                     used.
DATA PROCESSING DETAIL NOTES
RESOLVED DATA ISSUES
EXTRACT OF WATCHSTANDER'S LOG BY STATION NUMBER
CRUISE INTERPOLATION DOCUMENTATION
POST CRUISE PROCESSING DOCUMENTATION
WHPO DATA PROCESSING NOTES



WOCE EXPOCODES 316N145-11 (West leg), 316N145-12 (East leg);
Knorr Cruise 145 Leg 11; WHOI Internal code "KA45".
Document written by Sarah Zimmerman -July 1998; Document revised by Maggie 
Cook - December 1998.
Final version revised by Marshall Swartz - July 1999.

INTRODUCTION

The WHOI CTD Group supported PIs Harry Bryden and John Morrison in the 
occupation of WOCE Hydrographic Program line I1 across the N. Indian Ocean 
from 8/29/95 to 10/16/95.  The cruise was conducted as two legs, with 
stations 857 to 961 done on leg 1 and stations 962 to 1014 occupied on leg 2.  
Although the cruise completed the planned set of stations, multiple 
instrumental difficulties and failures plagued the voyage.  This report 
summarizes those problems and outlines the steps taken in the data reduction 
effort. A synopsis of the instrument problems is given in the ATSEA.DOC. 
Instrument failures meant that ICTDs from FSI constituted the primary 
instruments on the I1 cruise, the first time they have been so used by the WHOI 
Group.  In some respects, this cruise highlighted shortcomings in this new 
instrument.  Despite the difficulties, the data set produced by cruise end is of 
fair quality.  Pre-to-post laboratory temperature calibration analyses were 
quite consistent (differences of only 0.002°C) suggesting the absolute 
temperatures in the data are reasonable.  Calibrated CTD salinity profiles are 
quite consistent with the water sample salts, with residual salinity 
discrepancies with pressure between bottles and the profile data ranging between 
about +0.004 to -0.001 pss with depth.  CTD oxygen calibrations are not as good, 
owing in large part to bad sensor units (that were changed repeatedly during 
the cruise in search of a well-functioning sensor.  The sensor problems have 
been traced to manufacturing difficulties experienced by the producer 
combined with the company's poor quality control).  Noise levels in the 
dataset are somewhat larger than scientists are used to working with.  A 
general 0.002 pss salt noise level is present, about a factor of 2 larger 
than the norm.  CTD oxygen noise levels are 0.04ml/l, worsening to 0.06 for 
individual stations (ship roll/weather or bad sensor?).  Between legs 1 and 
2, modifications were made to the ICTD giving the oxygen current more 
resolution.  The general noise level was reduced to 0.03ml/l; better, but 
still slightly higher than the 0.02ml/l noise level typical of the MKIII CTD.


DATA DOCUMENTATION

Table of CTDs used by station number:
ICTD1338: stations 857, 863, 870 through 892, 978, 980 through 1014.
ICTD1344: stations 859 through 862, 865 through 869, 893 through 898, 900 
          through 977 and 979.
CTD09:    station 858.
CTD12:    stations 864 and 899.

There are no bottle files for stations 858, 867 and 869 due to the pressure 
signal having dropped out requiring the cast to be aborted.  Station 859 has 
bottles up to 800 dbars only due to fouling of the pylon.  Other station by 
station events are noted in the station by station log (file ATSEA.RPT 
submitted along with this document).

Final processed WOCE-format CTD files are named in the form KA45Dnnn.WC1, 
where nnn is the station number.  Note that stations 000 to 014 are actually 
stations 1000 through 1014 respectively.

Documentation files for this cruise are listed below:
      I1FINAL.DOC  this report.
      INTERP.DOC   list of linear interpolations performed in final 
                   processing of the data.
      ATSEA.DOC    a station by station description of CTD issues.

Final-revision CTD data files have been submitted with this data report. 


INSTRUMENT CONFIGURATION:

Four CTDs were available on the cruise: two MkIII (CTDs 9 and 12) and two FSI 
ICTDs (1338 and 1344), with multiple deck units (MkIII and FSI).  The CTDs 
were mounted in an SIO-designed 36-bottle frame fitted with a General 
Oceanics model 1016-36 36-position rosette pylon, driven through an SIO-
modified controller.

The MkIII CTDs both experienced failures early in the cruise, making the two 
FSI ICTDs the primary instruments by default.  Roughly 100 stations were made 
with ICTD 1344 as primary CTD and 50 stations with ICTD 1338 as primary CTD.  
Most commonly, the underwater frame was set up with two ICTD instruments: one 
sending data up the wire using its normal FSK configuration, and one set to 
record data internally, so that at the end of the station the data could be 
downloaded.

Significant signal interaction problems were encountered with the ICTDs and 
the General Oceanics pylon operating on a 10-km seacable, which resulted in 
data dropouts from the CTD and loss of confirmation of bottle closure from 
the pylon.  A temporary solution was achieved through electrical 
modifications to both the CTDs and the pylon deck controller to accommodate 
the long seacable, and data quality improved substantially.


ACQUISITION AND PROCESSING METHODS

Data from ICTD1338 were acquired at 26.0 Hz and processed with a temperature 
lag of 630 ms.  Data from ICTD 1344 were acquired at 26.0 Hz and with a 
temperature lag of 500 ms. The temperature lag was checked by comparing 
density reversals in theta salinity (TS) plots (Giles and McDonald, 1986).    
It was found that the aforementioned lags showed the least amount of looping 
or density reversals.  

For the first 9 stations (857-865) CTD data were acquired using an FSI DT-
1050 deck unit to demodulate the data.  From station 866 and beyond, data 
were acquired by an EG&G Mk-III deck unit to demodulate the data.  The deck 
units fed serial data to two personal computers running EG&G version 5.2 rev. 
2 CTD acquisition software (EG&G, Oceansoft Acquisition Manual, 1990), one 
providing graphical data to screen and plotter, and the other a running 
listing output.   Approach to seafloor of the CTD package was controlled by 
monitoring the pinger trace made by the direct and bottom return signals on 
the ship-provided PDR.

After each station, the CTD data were forwarded to another set of personal 
computers running both EG&G CTD post-processing 5.2 rev. 2 software and 
custom-built software from WHOI (Millard and Yang, 1993).  The data were 
first-differenced, lag corrected, pressure sorted, and centered into 2 dbar 
bins for final data quality control and analysis, including fitting to water 
sample salinity and oxygen results.  


SUMMARY OF LABORATORY CALIBRATIONS FOR CTDs 

Maren Tracy Plueddemann and Marshall Swartz calibrated the pressure, 
temperature, and conductivity sensors at the Woods Hole Oceanographic 
Institution CTD Calibration Laboratory pre and post-cruise.  The results are 
given below.


LABORATORY PRESSURE CALIBRATIONS

ICTD 1338:
      PRE CRUISE CAL
      Date: August 1995
      Notes: 1338 and 1344 kept together in cold bath for pressure 
             calibration.
             1338, 1344 and CTD1 received temperature calibration at same 
             time.
      Bath temperature during pressure calibration  = 1.85 deg C
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.337188E+01
             B = 0.100040E+00
             C =  -0.989186E-08 
             D = 0.121806E-12 
             Standard deviation of fit = 0.757851E+00

      POST CRUISE CAL
      Date: November 1995
      Notes: 1338 and 1344 received pressure and temperature calibrations at 
             the same time. 
      Bath temperature during pressure calibration  = 1.67 deg C
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.299558E+01 
             B = 0.999477E-01
             C = -0.646358E-08
             D = 0.900392E-13 
             Standard deviation of fit = 0.635441E+00

      Bath temperature during pressure calibration = 29.80 deg C
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.300466E+01
             B = 0.999851E-01
             C = -0.785380E-08
             D = 0.103497E-12
             Standard deviation of fit = 0.740938E+00

      COMBINED PRE- and POST-CRUISE CAL
      • Due to pressure bias shifts, a combination of the pre- and post-
        cruise pressure calibrations was selected for post cruise processing.

      Bath temperature during pressure calibrations were 1.85 and 1.67 deg C
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.326823E+01
             B = 0.999882E-01
             C = -0.798407E-08
             D = 0.103679E-12
             Standard deviation of fit = 0.766984E+00



ICTD 1344:
      PRE CRUISE CAL
      Date:  August 1995
      Notes: 1338 and 1344 kept together in cold bath for pressure 
      calibration.
             1338, 1344 and CTD1 received temperature calibration at same 
             time.
      Bath temperature during pressure calibration = 1.85 deg C
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.203003E+01
             B = 0.999794E-01
             C = -0.166617E-08
             D = 0.175895E-13
             Standard deviation of fit = 0.490572E+00

      POST CRUISE CAL
      Date: November 1995
      • This post cruise calibration was selected for post-cruise processing.
      Notes: 1338 and 1344 received pressure and temperature calibrations at 
      the same time. 
      Bath temperature during pressure calibration = 1.67 deg C
      Resulting polynomial coefficients for a third order fit: 
     (A+Bx+Cx^2+Dx^3):
             A = 0.162374E+01
             B = 0.999549E-01
             C = -0.293230E-09
             D = 0.372714E-14
             Standard deviation of fit = 0.341575E+00

      Bath temperature during pressure calibration = 29.80 deg C
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.167806E+01
             B = 0.999615E-01
             C = -0.720102E-09
             D = 0.938970E-14
             Standard deviation of fit = 0.462750E+00

PRESSURE BIAS BY STATION NUMBER:

The following table summarizes the pressure bias applied during post-cruise 
data-processing, based upon the pressure measured by the CTD immediately 
prior to entering the water and immediately following recovery from the 
water.


sta  ctd#    bias_down     bias_up       sta  ctd#    bias_down     bias_up 
---  ----  ------------  ------------    ---  ----  ------------  ------------
857  1338  0.296823E+01  0.296823E+01    897  1344  0.143003E+01  0.143003E+01
858    09  -.452144E+01  -.452144E+01    898  1344  0.113003E+01  0.113003E+01
859  1344  0.183003E+01  0.183003E+01    899    12  -.381194E+02  -.381194E+02
860  1344  0.223003E+01  0.223003E+01    900  1344  0.133003E+01  0.133003E+01
861  1344  0.243003E+01  0.243003E+01    901  1344  0.153003E+01  0.153003E+01
862  1344  0.233003E+01  0.233003E+01    902  1344  0.143003E+01  0.143003E+01
863  1338  -.442144E+01  -.442144E+01    903  1344  0.153003E+01  0.153003E+01
864    12  -.391194E+02  -.391194E+02    904  1344  0.143003E+01  0.143003E+01
865  1344  0.233003E+01  0.233003E+01    905  1344  0.123003E+01  0.123003E+01
866  1344  0.203003E+01  0.203003E+01    906  1344  0.113003E+01  0.113003E+01
867  1344  0.223003E+01  0.223003E+01    907  1344  0.113003E+01  0.113003E+01
868  1344  0.193003E+01  0.193003E+01    908  1344  0.123003E+01  0.123003E+01
869  1344  0.213003E+01  0.213003E+01    909  1344  0.300300E-01  0.300300E-01
870  1338  0.216823E+01  0.216823E+01    910  1344  0.133003E+01  0.133003E+01
871  1338  0.266823E+01  0.266823E+01    911  1344  0.930030E+00  0.930030E+00
872  1338  0.256823E+01  0.256823E+01    912  1344  0.113003E+01  0.113003E+01
873  1338  0.246823E+01  0.246823E+01    913  1344  0.830030E+00  0.830030E+00
874  1338  0.256823E+01  0.256823E+01    914  1344  0.830030E+00  0.830030E+00
875  1338  0.276823E+01  0.276823E+01    915  1344  0.830030E+00  0.830030E+00
876  1338  0.246823E+01  0.246823E+01    916  1344  0.113003E+01  0.113003E+01
877  1338  0.256823E+01  0.256823E+01    917  1344  0.123003E+01  0.123003E+01
878  1338  0.246823E+01  0.246823E+01    918  1344  0.930030E+00  0.930030E+00
879  1338  0.276823E+01  0.276823E+01    919  1344  0.123003E+01  0.123003E+01
880  1338  0.226823E+01  0.226823E+01    920  1344  0.123003E+01  0.123003E+01
881  1338  0.246823E+01  0.246823E+01    921  1344  0.630030E+00  0.630030E+00
882  1338  0.276823E+01  0.276823E+01    922  1344  0.113003E+01  0.113003E+01
883  1338  0.226823E+01  0.226823E+01    923  1344  0.113003E+01  0.113003E+01
884  1338  0.206823E+01  0.206823E+01    924  1344  0.630030E+00  0.630030E+00
885  1338  0.196823E+01  0.196823E+01    925  1344  0.630030E+00  0.630030E+00
886  1338  0.266823E+01  0.266823E+01    926  1344  0.730030E+00  0.730030E+00
887  1338  0.226823E+01  0.226823E+01    927  1344  0.630030E+00  0.630030E+00
888  1338  0.216823E+01  0.216823E+01    928  1344  0.730030E+00  0.730030E+00
889  1338  0.216823E+01  0.216823E+01    929  1344  0.830030E+00  0.830030E+00
890  1338  0.196823E+01  0.196823E+01    930  1344  0.930030E+00  0.930030E+00
891  1338  0.196823E+01  0.196823E+01    931  1344  0.930030E+00  0.930030E+00
892  1338  0.196823E+01  0.196823E+01    932  1344  0.930030E+00  0.930030E+00
893  1344  0.183003E+01  0.183003E+01    933  1344  0.430030E+00  0.430030E+00
894  1344  0.163003E+01  0.163003E+01    934  1344  0.630030E+00  0.630030E+00
895  1344  0.123003E+01  0.123003E+01    935  1344  0.630030E+00  0.630030E+00
896  1344  0.103003E+01  0.103003E+01    936  1344  0.630030E+00  0.630030E+00


sta  ctd#    bias_down     bias_up       sta  ctd#    bias_down     bias_up 
---  ----  ------------  ------------    ---  ----  ------------  ------------
937  1344  0.330030E+00  0.330030E+00    976  1344  0.730030E+00  0.730030E+00
938  1344  0.630030E+00  0.630030E+00    977  1344  0.103003E+01  0.103003E+01
939  1344  0.830030E+00  0.830030E+00    978  1338  0.266823E+01  0.266823E+01
940  1344  0.730030E+00  0.730030E+00    979  1344  0.133003E+01  0.133003E+01
941  1344  0.730030E+00  0.730030E+00    980  1338  0.296823E+01  0.296823E+01
942  1344  0.830030E+00  0.830030E+00    981  1338  0.206823E+01  0.206823E+01
943  1344  0.830030E+00  0.830030E+00    982  1338  0.276823E+01  0.276823E+01
944  1344  0.730030E+00  0.730030E+00    983  1338  0.276823E+01  0.276823E+01
945  1344  0.830030E+00  0.830030E+00    984  1338  0.276823E+01  0.276823E+01
946  1344  0.630030E+00  0.630030E+00    985  1338  0.256823E+01  0.256823E+01
947  1344  0.230030E+00  0.230030E+00    986  1338  0.226823E+01  0.226823E+01
948  1344  0.630030E+00  0.630030E+00    987  1338  0.176823E+01  0.176823E+01
949  1344  0.530030E+00  0.530030E+00    988  1338  0.266823E+01  0.266823E+01
950  1344  0.430030E+00  0.430030E+00    989  1338  0.256823E+01  0.256823E+01
951  1344  0.930030E+00  0.930030E+00    990  1338  0.266823E+01  0.266823E+01
952  1344  0.930030E+00  0.930030E+00    991  1338  0.256823E+01  0.256823E+01
953  1344  0.103003E+01  0.103003E+01    992  1338  0.256823E+01  0.256823E+01
954  1344  0.113003E+01  0.113003E+01    993  1338  0.256823E+01  0.256823E+01
955  1344  0.730030E+00  0.730030E+00    994  1338  0.246823E+01  0.246823E+01
956  1344  0.930030E+00  0.930030E+00    995  1338  0.246823E+01  0.246823E+01
957  1344  0.113003E+01  0.113003E+01    996  1338  0.246823E+01  0.246823E+01
958  1344  0.103003E+01  0.103003E+01    997  1338  0.246823E+01  0.246823E+01
959  1344  0.930030E+00  0.930030E+00    998  1338  0.236823E+01  0.236823E+01
960  1344  0.113003E+01  0.113003E+01    999  1338  0.236823E+01  0.236823E+01
961  1344  0.530030E+00  0.530030E+00    000  1338  0.236823E+01  0.236823E+01
962  1344  0.143003E+01  0.143003E+01    001  1338  0.246823E+01  0.246823E+01
963  1344  0.103003E+01  0.103003E+01    002  1338  0.256823E+01  0.256823E+01
964  1344  0.133003E+01  0.133003E+01    003  1338  0.256823E+01  0.256823E+01
965  1344  0.103003E+01  0.103003E+01    004  1338  0.256823E+01  0.256823E+01
966  1344  0.133003E+01  0.133003E+01    005  1338  0.196823E+01  0.196823E+01
967  1344  0.930030E+00  0.930030E+00    006  1338  0.186823E+01  0.186823E+01
968  1344  0.830030E+00  0.830030E+00    007  1338  0.196823E+01  0.196823E+01
969  1344  0.830030E+00  0.830030E+00    008  1338  0.206823E+01  0.206823E+01
970  1344  0.133003E+01  0.133003E+01    009  1338  0.196823E+01  0.196823E+01
971  1344  0.143003E+01  0.143003E+01    010  1338  0.196823E+01  0.196823E+01
972  1344  0.153003E+01  0.153003E+01    011  1338  0.196823E+01  0.196823E+01
973  1344  0.430030E+00  0.430030E+00    012  1338  0.196823E+01  0.196823E+01
974  1344  0.133003E+01  0.133003E+01    013  1338  0.196823E+01  0.196823E+01
975  1344  0.103003E+01  0.103003E+01    014  1338  0.196823E+01  0.196823E+01


LABORATORY TEMPERATURE CALIBRATIONS

ICTD 1338 had a small change, less than 0.002 deg C.  The pre and post 
temperature calibrations were averaged to be used with the post cruise 
processing.  The ICTD 1344 temperature calibration changed pre to post cruise 
with a bias shift of  +0.002 deg C. CTD reading warmer at the post cruise 
calibration.  The point at where the temperature shift occurred was looked 
for but not found.   The most reliable search was to look at data from the 
same station where both primary and internal recording CTDs were used.  They 
did not show where the jump occurred.  The fast thermistor channel data were 
also compared at points where the salinity calibration changed.  There was 
not enough proof to point to a spot where the jump occurred, so an average of 
the pre and post cruise calibrations was used to process the data.

ICTD 1338 SLOW PLATINUM THERMOMETER CHANNEL

      PRE CRUISE CAL
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = 0.285975E-02
             B = 0.500231E-03
             C = -0.177714E-10
             D = 0.194501E-15 
             Standard deviation of fit = 0.373642E-03

POST CRUISE CAL
Resulting polynomial coefficients for a third order fit: 
(A+Bx+Cx^2+Dx^3):
             A = 0.918509E-03
             B = 0.500358E-03
             C = -0.190649E-10
             D = 0.192328E-15
             Standard deviation of fit = 0.352686E-03

      COMBINED PRE AND POST CRUISE CAL
      • A combined calibration was used for post cruise processing as noted above.
      Resulting polynomial coefficients for a third order fit:   
      (A+Bx+Cx^2+Dx^3):
             A = 0.186857E-02
             B = 0.500298E-03
             C = -0.185827E-10
             D = 0.195224E-15
             Standard deviation of fit = 0.594841E-03

ICTD 1338 FAST THERMISTOR CHANNEL
Note:  ICTD1338 fast thermistor temperature data was used to check for 
temperature shifts during cruise, but did not contribute to the final 
processed temperature data.

      PRE CRUISE CAL
      Note: the second order fit was used during the cruise.   The third 
      order fit was used post cruise to compare changes pre to post cruise 
      for the fast thermistor channel.
      Resulting polynomial coefficients for a second order fit: (A+Bx+Cx^2):
             A = 0.915609E-01
             B = 0.495852E-03
             C = 0.333829E-10
      Standard deviation of fit = 0.693632E-01
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.187870E-01
             B = 0.524023E-03
             C = -0.116195E-08
             D = 0.129201E-13
             Standard deviation of fit = 0.168422E-02
      POST CRUISE CAL
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.186425E-01
             B = 0.524085E-03
             C = -0.116322E-08
             D = 0.129201E-13
             Standard deviation of fit = 0.175345E-02

ICTD 1338 OXYGEN TEMPERATURE CHANNEL

      PRE CRUISE CAL
      Resulting polynomial coefficients for a second order fit: (A+Bx+Cx^2):
             A = -0.216281E+01
             B = 0.160633E+00
             C = -0.121723E-03
             Standard deviation of fit = 0.158769E+00
             
      POST CRUISE CAL
      This post-cruise calibration was used with the oxygen algorithms to 
      produce the final dataset.

      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.277188E+01
             B = 0.183254E+00
             C = -0.324103E-03

             D = 0.503239E-06
             Standard deviation of fit = 0.361886E-01

ICTD 1344 SLOW PLATINUM THERMOMETER

      PRE CRUISE CAL
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.639595E-02
             B = 0.500576E-03
             C = -0.219271E-10
             D = 0.227245E-15
             Standard deviation of fit = 0.260050E-03

      POST CRUISE CAL
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A =-0.853971E-02
             B = 0.500625E-03
             C = -0.235555E-10
             D = 0.243046E-15
             Standard deviation of fit = 0.668181E-03
      COMBINED PRE AND POST CRUISE CAL
      • A combined calibration was used for final post cruise processing.
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.748166E-02
             B = 0.500600E-03
             C = -0.226875E-10
             D = 0.234567E-15
             Standard deviation of fit = 0.940009E-03

ICTD 1344 FAST PLATINUM THERMOMETER CHANNEL 
Note: The fast platinum thermometer channel was used as a secondary reference 
to judge changes to the ICTD 1344 slow platinum thermometer channel during 
the cruise.  These measurements did not contribute to the final processed 
data.

      PRE CRUISE CAL
      Resulting polynomial coefficients for a second order fit: (A+Bx+Cx^2):
             A = -0.164421E-02
             B = 0.499960E-03
             C = 0.832749E-12
             Standard deviation of fit = 0.146257E-02
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.390910E-02
             B = 0.500535E-03
             C = -0.235454E-10
             D = 0.263094E-15
             Standard deviation of fit = 0.356128E-03

      POST CRUISE CAL
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.707179E-02
             B = 0.500630E-03
             C = -0.267632E-10
             D = 0.294216E-15
             Standard deviation of fit = 0.585656E-03


ICTD 1344 FAST THERMISTOR CHANNEL
Note: ICTD1344 fast thermistor temperature data was used to check for 
temperature shifts during cruise, but did not contribute to the final 
processed temperature data.

      PRE CRUISE CAL
      Resulting polynomial coefficients for a second order fit: (A+Bx+Cx^2):
             A = 0.889859E-01
             B = 0.496237E-03
             C = 0.282361E-10
             Standard deviation of fit = 0.677849E-01
             
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.188737E-01
             B = 0.523767E-03
             C = -0.113985E-08
             D = 0.126255E-13
             Standard deviation of fit = 0.182910E-02

      POST CRUISE CAL
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.181959E-01
             B = 0.523798E-03
             C = -0.113971E-08
             D = 0.126209E-13
             Standard deviation of fit = 0.171024E-02


ICTD 1344 OXYGEN TEMPERATURE CHANNEL

      PRE CRUISE CAL
      Resulting polynomial coefficients for a second order fit: (A+Bx+Cx^2):
             A = -0.336502E+01
             B = 0.146252E+00
             C = -0.637599E-04
             Standard deviation of fit = 0.293626E+00
             
      POST CRUISE CAL
      • The post-cruise oxygen temperature calibration was used with the 
        oxygen algorithms for the final dataset.
      Resulting polynomial coefficients for a third order fit: 
      (A+Bx+Cx^2+Dx^3):
             A = -0.477833E+01
             B = 0.194995E+00
             C = -0.466521E-03
             D = 0.921395E-06 
             Standard deviation of fit = 0.714265E-01




SALINITY CALIBRATIONS

The CTD conductivity sensor data were fit to the water sample conductivity as 
described in Millard and Yang (1993). The stations were fit by groups 
according to the drift of the conductivity sensor over time.

Plot results of deep water theta/S revealed that there was a difference 
between CTDs:

1338: *.PRS CTD salt read too high ~0.002 psu or temperature was too low 
      compared to *.SEA file. 
1344: *.PRS CTD salt read too low ~0.001 psu or temperature was too high 
      compared to *.SEA file. 

The consistency of the bias between stations indicates it was probably not a 
real ocean measurement such as measuring internal waves, but some kind of 
instrument, package dynamic or bottle artifact.  All ICTD 1338 stations have 
a significant bias, with the downtrace always saltier than the bottles.  The 
uptrace has been fit well, but the uptrace is fresher than the downtrace.  To 
correct for the difference, the downtrace salinity data for the group of 
stations 978 and 980 through 1014 were fit to the bottle data.  This was 
accomplished by processing the 2-decibar averaged downtrace CTD data against 
the bottle data, and provided a more acceptable fit for these stations.  
Figures 1 and 2 demonstrate the CTD salt to bottle salt fits for stations 982 
through 1000 using downtrace data, and figures 3 and 4 demonstrate the same 
fits using uptrace data as is normally done.

ICTD 1338 stations 870 through 892 seemed to fit well after forcing the CTD 
salt data to agree with the bottom bottle data, and so were not refit using 
the downtrace.  ICTD 1344 downtraces trend toward being fresher than the 
bottles.  The uptrace and downtrace agree, but the fits were not working 
well.  Some of the fits were recalculated, with emphasis on matching up the 
CTD and salts in the bottom water.

CTD comparisons were made with the primary CTD and memory CTD data from the 
same stations.  Pressure agreed very well, with bottom depths agreeing within 
1dbar on the stations checked.  Temperature would stray, +/-.002 at the 
bottom, sometimes ICTD 1338 being warmer, and sometimes ICTD 1344 was warmer.  
This is most likely a factor of the location of the telemetering CTD on the 
sampler frame being different than the position of the memory mode CTD and 
thus in a different waterpath.  Both CTDs could have thermal contamination of 
the temperature signal from the frame while sampling at a bottle stop.


Notes for particular stations' salinity calibrations 

Stations 936-938, 940-941:
A pressure dependent difference between bottle and CTD salinities could not 
be removed without changing the conductivity cell geometry correction terms 
for pressure (ALPHA) and temperature (BETA).  After station 942, the 
conductivity cell was cleaned due to slime buildup.  The difficult 
calibrations from stations 936 to 942 could have been induced by fouling or 
buildup of slime on the conductivity cell. 

Stations 936, 937 and 938:
BETA was changed from 1.5e-8 to 0.75e-8 
Stations 940 and 941 have BETA changed from 1.5e-8 to 0.75e-8, and 
ALPHA changed from -6.5e-6 to -9.75e-6.

Station 923 and 954:
Salt changes that looked questionable until the uptrace was overlaid and 
followed the shape of the downtrace.  Station 923 freshens around 2 deg C.  
Station 954 has spikes and a shift at 1750dbar, 1900dbar and 2250 dbar that 
are clearly repeated in the uptrace. 


Table 1: Final conductivity coefficients applied by station number.  The 
         coefficients used to scale downtrace conductivity data for the I1 
         stations are listed below.

         stn      bias          slope          stn      bias          slope
         ---  ------------  ------------       ---  ------------  ------------
         857  0.269148E-02  0.999756E-03       896  -.823240E-03  0.999989E-03
         858  0.148422E-01  0.997105E-03       897  -.823240E-03  0.999989E-03
         859  0.758850E-02  0.999569E-03       898  -.823240E-03  0.999989E-03
         860  0.758850E-02  0.999569E-03       899  0.187740E-01  0.100097E-02
         861  0.758850E-02  0.999569E-03       900  -.823240E-03  0.999992E-03
         862  0.758850E-02  0.999569E-03       901  -.823240E-03  0.999992E-03
         863  0.269148E-02  0.999816E-03       902  -.823240E-03  0.999992E-03
         864  0.187740E-01  0.100097E-02       903  -.823240E-03  0.999992E-03
         865  0.758850E-02  0.999569E-03       904  -.823240E-03  0.999992E-03
         866  0.758850E-02  0.999569E-03       905  -.823240E-03  0.999992E-03
         867  0.758850E-02  0.999569E-03       906  -.823240E-03  0.999992E-03
         868  0.758850E-02  0.999649E-03       907  -.823240E-03  0.999992E-03
         869  0.758850E-02  0.999569E-03       908  -.823240E-03  0.999992E-03
         870  0.269148E-02  0.999795E-03       909  -.823240E-03  0.999989E-03
         871  0.269148E-02  0.999795E-03       910  -.106344E-02  0.100004E-02
         872  0.269148E-02  0.999795E-03       911  -.106344E-02  0.100004E-02
         873  0.269148E-02  0.999795E-03       912  -.106344E-02  0.100004E-02
         874  0.269148E-02  0.999795E-03       913  -.106344E-02  0.100004E-02
         875  0.269148E-02  0.999795E-03       914  -.106344E-02  0.100004E-02
         876  0.269148E-02  0.999795E-03       915  -.106344E-02  0.100004E-02
         877  0.269148E-02  0.999795E-03       916  -.106344E-02  0.100004E-02
         878  0.269148E-02  0.999795E-03       917  -.106344E-02  0.100004E-02
         879  0.269148E-02  0.999795E-03       918  -.128407E-03  0.100004E-02
         880  0.269148E-02  0.999795E-03       919  -.128407E-03  0.100004E-02
         881  0.269148E-02  0.999795E-03       920  -.128407E-03  0.100004E-02
         882  0.269148E-02  0.999795E-03       921  -.128407E-03  0.100004E-02
         883  0.269148E-02  0.999795E-03       922  -.128407E-03  0.100004E-02
         884  0.269148E-02  0.999795E-03       923  -.128407E-03  0.100004E-02
         885  0.269148E-02  0.999795E-03       924  -.128407E-03  0.100004E-02
         886  0.269148E-02  0.999795E-03       925  -.128407E-03  0.100004E-02
         887  0.269148E-02  0.999795E-03       926  -.128407E-03  0.100004E-02
         888  0.269148E-02  0.999795E-03       927  -.128407E-03  0.100004E-02
         889  0.269148E-02  0.999795E-03       928  -.128407E-03  0.100004E-02
         890  0.269148E-02  0.999795E-03       929  -.296800E-03  0.100006E-02
         891  0.269148E-02  0.999795E-03       930  -.296800E-03  0.100006E-02
         892  0.269148E-02  0.999795E-03       931  -.296800E-03  0.100006E-02
         893  -.823240E-03  0.999989E-03       932  -.296800E-03  0.100006E-02
         894  -.823240E-03  0.999989E-03       933  -.296800E-03  0.100006E-02
         895  -.823240E-03  0.999989E-03       934  -.296800E-03  0.100014E-02
         
         
         stn      bias          slope          stn      bias          slope
         ---  ------------  ------------       ---  ------------  ------------
         935  -.296800E-03  0.100006E-02       975  -.519660E-02  0.100019E-02
         936  0.141056E-02  0.100005E-02       976  -.519660E-02  0.100019E-02
         937  0.141056E-02  0.100005E-02       977  -.390173E-02  0.100007E-02
         938  0.141056E-02  0.100005E-02       978  0.419290E-03  0.999988E-03
         939  0.141056E-02  0.100005E-02       979  -.390173E-02  0.100015E-02
         940  -.514493E-02  0.100032E-02       980  0.419290E-03  0.999994E-03
         941  -.514493E-02  0.100032E-02       981  0.419290E-03  0.999994E-03
         942  -.514493E-02  0.100030E-02       982  0.419290E-03  0.999994E-03
         943  -.891709E-03  0.100003E-02       983  0.419290E-03  0.999994E-03
         944  -.891709E-03  0.100003E-02       984  0.419290E-03  0.999994E-03
         945  -.891709E-03  0.100003E-02       985  0.419290E-03  0.999994E-03
         946  -.891709E-03  0.100004E-02       986  0.419290E-03  0.999994E-03
         947  -.891709E-03  0.100004E-02       987  0.419290E-03  0.999994E-03
         948  -.891709E-03  0.100004E-02       988  0.419290E-03  0.999994E-03
         949  -.891709E-03  0.100004E-02       989  0.419290E-03  0.999994E-03
         950  -.891709E-03  0.100004E-02       990  0.419290E-03  0.999994E-03
         951  -.891709E-03  0.999983E-03       991  0.419290E-03  0.999994E-03
         952  -.891709E-03  0.100004E-02       992  0.419290E-03  0.999994E-03
         953  -.891709E-03  0.100004E-02       993  0.419290E-03  0.999994E-03
         954  -.891709E-03  0.100004E-02       994  0.419290E-03  0.999994E-03
         955  -.891709E-03  0.100004E-02       995  0.419290E-03  0.999994E-03
         956  -.891709E-03  0.100004E-02       996  0.419290E-03  0.999994E-03
         957  -.891709E-03  0.100004E-02       997  0.419290E-03  0.999994E-03
         958  -.891709E-03  0.999997E-03       998  0.419290E-03  0.999994E-03
         959  -.891709E-03  0.100004E-02       999  0.419290E-03  0.999994E-03
         960  -.891709E-03  0.100008E-02       000  0.419290E-03  0.999994E-03
         961  -.891709E-03  0.100008E-02       001  0.419290E-03  0.999994E-03
         962  -.390173E-02  0.100009E-02       002  0.419290E-03  0.999994E-03
         963  -.390173E-02  0.100009E-02       003  0.419290E-03  0.999994E-03
         964  -.519660E-02  0.100021E-02       004  0.419290E-03  0.999994E-03
         965  -.519660E-02  0.100021E-02       005  0.419290E-03  0.999994E-03
         966  -.519660E-02  0.100021E-02       006  0.419290E-03  0.999994E-03
         967  -.519660E-02  0.100021E-02       007  0.419290E-03  0.999994E-03
         968  -.519660E-02  0.100021E-02       008  0.419290E-03  0.999994E-03
         969  -.519660E-02  0.100021E-02       009  0.419290E-03  0.999994E-03
         970  -.519660E-02  0.100019E-02       010  0.419290E-03  0.999994E-03
         971  -.519660E-02  0.100019E-02       011  0.419290E-03  0.999994E-03
         972  -.519660E-02  0.100019E-02       012  0.419290E-03  0.999994E-03
         973  -.519660E-02  0.100019E-02       013  0.419290E-03  0.999994E-03
         974  -.519660E-02  0.100019E-02       014  0.419290E-03  0.999994E-03
         
         
         The coefficients used to scale uptrace conductivity data for selected I1 
         stations are listed below.
         
         
         stn      bias          slope          stn      bias          slope
         ---  ------------  ------------       ---  ------------  ------------
         978  0.216462E-02  0.999940E-03       997  0.216462E-02  0.999975E-03
         980  0.216462E-02  0.999940E-03       998  0.216462E-02  0.999975E-03
         981  0.216462E-02  0.999940E-03       999  0.216462E-02  0.999975E-03
         982  0.216462E-02  0.999940E-03       000  0.216462E-02  0.999975E-03
         983  0.216462E-02  0.999975E-03       001  0.216462E-02  0.999975E-03
         984  0.216462E-02  0.999975E-03       002  0.216462E-02  0.999975E-03
         985  0.216462E-02  0.999975E-03       003  0.216462E-02  0.999975E-03
         986  0.216462E-02  0.999975E-03       004  0.216462E-02  0.999975E-03
         987  0.216462E-02  0.999975E-03       005  0.216462E-02  0.999975E-03
         988  0.216462E-02  0.999975E-03       006  0.216462E-02  0.999975E-03
         989  0.216462E-02  0.999975E-03       007  0.216462E-02  0.999975E-03
         990  0.216462E-02  0.999975E-03       008  0.216462E-02  0.999975E-03
         991  0.216462E-02  0.999975E-03       009  0.216462E-02  0.999975E-03
         992  0.216462E-02  0.999975E-03       010  0.216462E-02  0.999975E-03
         993  0.216462E-02  0.999975E-03       011  0.216462E-02  0.999975E-03
         994  0.216462E-02  0.999975E-03       012  0.216462E-02  0.999975E-03
         995  0.216462E-02  0.999975E-03       013  0.216462E-02  0.999975E-03
         996  0.216462E-02  0.999975E-03       014  0.216462E-02  0.999975E-03

Note: Uptrace CTD conductivity data was fit to the bottle salts for stations 
      978 and 980 through 1014 as described in the preceding documentation to 
      achieve a better fit.


SALINITY FITTING RESULTS:

The following plots show the differences between the rosette and CTD salts 
across legs one and two.  It is important to note that these plots cover both 
CTDs, each of which were opened on several occasions potentially causing 
calibration changes.  In the beginning of the cruise many mechanical problems 
were encountered.  (see ATSEA.doc).

Figure 1: Leg 1 - Difference between calibrated downtrace CTD salts and the 
          rosette salinity data

Figure 2: Leg 2 - Difference between calibrated downtrace CTD salts and 
          rosette salinity data

Figure 3: Leg 1 Differences between calibrated uptrace CTD salts in rosette 
          file (scaled with separate multiple regression fit from down 
          salinities) and rosette salts.  Note that the residuals are 
          significantly better for the uptrace data.  Fits to the uptrace 
          data were applied to the uptrace CTD data in the rosette file.  Due 
          to hysteresis, fits to the downtrace data needed to be applied to 
          the downtrace CTD data files for stations 978 to 1014.

Figure 4: Leg 2: Differences between scaled uptrace CTD salts in the rosette 
          file (separate multiple regression fit from down salinities) and 
          the rosette salt data.



OXYGEN CALIBRATIONS:

SENSOR FAILURES
The CTD oxygen data presented special problems from the beginning.  While all 
four CTDs were initially fitted with new oxygen sensors, and spares were 
brought on the cruise, the stations were plagued with sensor failures and 
erratic sensor data.   The CTDs all used Sensormedics brand polarographic 
oxygen sensors, and due to recent experience of failures, it was expected that 
sensor changes would have to be made.  However, the failure rate exceeded our 
low expectations, with seven replacement sensors being used.

Oxygen sensors were replaced following the stations listed below:

                          Station  CTD   Sensor s/n
                          -------  ----  ----------
                            865    1344   5-06-03
                            910    1344   5-06-02
                            923    1344   5-07-02
                            930    1344   4-10-2
                            980    1344   4-12-04
                            991    1344   5-06-01
 
The CTDs used interchangeable sensor assemblies, which permitted the oxygen 
thermistor and sensor module to simply be unplugged and a new one installed 
if a problem was found.  This speeded up the changeout of failed oxygen 
sensors.  However, since each CTD's oxygen temperature channel is calibrated 
to a specific module, swapping a module out changes the oxygen temperature 
calibration.  Due to the large number of failures of sensors, modules were 
interchanged between the ICTDs on several occasions, and necessitated special 
attention to fitting of the data.  

OXYGEN DATA FITTING
Some stations fit well using normal fitting routines, while others had a 
definite pressure dependent shape in the residuals.  A similar shape recurred 
in different groups.  The shape was more pronounced in some groups than 
others.    A weight of 0.8 and lag of 1 was consistent from a few of the 
larger groups. Most of the groups had this weight and lag held during the 
fits since many groups came up with weights over 1 and lags below 0 when 
allowed to fit for those parameters.  For the groups with the pressure 
dependent shape in the residuals, tcor was held at some value lower than the 
fit originally came up with.  Usually tcor was adjusted by -0.002 and the 
group refit.  The resulting residuals between 2000 to 5000 dbars would be 
centered around 0 with a spread reduced from +/-0.1 to +/-0.04 but the shape 
would remain in the upper 2000 dbars.   


Special notes for fitting oxygen data for particular stations:

The oxygen temperature (OT) coefficients were changed for the post 
processing.  There were several instances of the CTD profile not reaching the 
oxygen minimum, or overshooting the minimum.  This may have been due to not 
having the proper OT coefficients in the at-sea station header files.  These 
were corrected during post-processing so all calibration files now have the 
proper OT coefficients for each CTD. 

OT coefficient changes:

       Station applied to   Change made
       ------------------   ------------------------------------------
          857, 870-892      replaced wrong 38 bias with right 38 bias.
             859-862        replaced 38 OT cal with 44 OT cal.
             865-869        left as is.
        893-979, 899, 978   replaced 38 OT wrong bias with 44 OT cal.
               979          replaced wrong 38 bias with right 38 bias.
               980          replaced wrong 38 bias with right 38 bias.
             981-004        replaced wrong 38 bias with right 38 bias.
             005-014        replaced wrong 38 bias with right 38 bias.

Stations 859 to 862 were taken with ICTD 1344 but used ICTD1338's oxygen 
assembly.  1344's OT calibration terms were put into the cal file.

Stations 877, 878, 879 and 004 were scaled using the at-sea OT and oxygen 
current (OC) terms.  With the new OT terms, it was not possible to get as 
good a fit as the at-sea results.  The terms arrived at had unrealistic 
numbers such as a negative lag but was used anyway for the resulting good 
fit.

Stations 857 and 858, test stations, had the oxygen quality word flagged '4' 
(bad) in the downtrace.  All the bottles were deep and not useful for finding 
a fit for the whole profile.

Station 859, the next station in the same locations as 857 and 858, had 
bottles except for the top 800dbar due to a pylon failure.  Even with a 
better fit this top should be labeled '3' (questionable).

Station 860, a test station for water sampling.  The downtrace oxygen was 
labeled '4' due to all bottles fired deep.

Stations 906 to 904 have clear shape in the bottom water that may or may not 
be real.  The uptrace looks as if it follows the shapes loosely, not really 
until the larger features around 2000dbar does it really follow the 
downtrace.  Station 937 had extra bottles taken deep to watch the +/- 
0.05ml/l variation in oxygen.  The bottles do look like they agree with the 
oxygen.  

Station 987, a -0.04 ml/l shift in oxygen at 2711dbar does not look real, and 
does not agree with bottle or following stations. It has been flagged '3' 
(questionable).


TABLE 2: OXYGEN FITTING COEFFICIENTS FOR STATIONS WITH NORMAL ALGO-RITHM
         Below is a list of the coefficients used to scale the oxygen data 
         for all but 53 stations that have a special fitting routine applied 
         (noted as "special fit"). 

         stn   bias     slope          pcor       tcor    wt    lag
         ---  ------  ----------    ----------  -------  ----   ----
         857  -0.011  0.2915E-03    0.6243E-03   0.0156  0.60   3.00
         858  -0.023  0.1192E-02    0.1798E-03  -0.0300  0.80   1.00 
         859  -0.023  0.1192E-02    0.1798E-03  -0.0300  0.80   1.00 
           860 - 862 special fit.
         863   0.004  0.1296E-02    0.1407E-03  -0.0524  0.60   0.30
         864  -1.375  0.1136E-03    0.2034E-03  -0.0522  0.60   1.00 
           865 - 869 special fit.
         870   0.006  0.3862E-03    0.6243E-03   0.0156  0.60   3.00 
         871   0.009  0.6467E-03    0.3590E-03   0.0064  0.60   3.00 
         872   0.009  0.6467E-03    0.3590E-03   0.0064  0.60   3.00 
         873   0.039  0.8729E-03    0.1179E-03  -0.0155  0.60   3.00 
         874   0.039  0.8729E-03    0.1179E-03  -0.0155  0.60   3.00 
         875   0.022  0.1472E-02   -0.1200E-03  -0.0397  0.60   3.00 
         876   0.022  0.1472E-02   -0.1200E-03  -0.0397  0.60   3.00 
         877   0.004  0.1318E-02   -0.4643E-05  -0.0341  0.10   4.00
         878  -0.018  0.4243E-02   -0.2527E-03  -0.0677  1.32  -0.3
         879  -0.018  0.4243E-02   -0.2527E-03  -0.0677  1.32  -0.3
           880-892 special fit.
         893   0.005  0.1170E-02    0.1499E-03  -0.0272  0.80   1.00 
         894   0.022  0.1141E-02    0.1508E-03  -0.0271  0.80   1.00 
         895   0.009  0.1273E-02    0.1416E-03  -0.0298  0.80   1.00 
         896   0.017  0.1281E-02    0.1444E-03  -0.0275  0.80   1.00
         897   0.017  0.1281E-02    0.1444E-03  -0.0275  0.80   1.00
         898   0.019  0.1316E-02    0.1398E-03  -0.0275  0.80   1.00
         899  -1.427  0.1162E-03    0.1901E-03  -0.0283  0.60   1.00 
         900   0.017  0.1281E-02    0.1444E-03  -0.0275  0.80   1.00
         901   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         902   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         903   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         904   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         905   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         906   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         907   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         908   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         909   0.011  0.1376E-02    0.1469E-03  -0.0294  0.80   1.23
         910   0.036  0.1149E-02    0.1427E-03  -0.0270  0.80   1.00
         911   0.003  0.1214E-02    0.1503E-03  -0.0280  0.80   1.00
           912 - 922 special fit.
         
         
         stn   bias     slope          pcor       tcor    wt    lag
         ---  ------  ----------    ----------  -------  ----   ----
         923  -0.006  0.1045E-02    0.1665E-03  -0.0243  0.74   9.34 
         924  -0.006  0.1045E-02    0.1665E-03  -0.0243  0.74   9.34 
         925   0.000  0.1080E-02    0.1463E-03  -0.0240  0.80   1.00 
         926   0.000  0.1080E-02    0.1463E-03  -0.0240  0.80   1.00 
         927   0.000  0.1080E-02    0.1463E-03  -0.0240  0.80   1.00 
         928   0.000  0.1080E-02    0.1463E-03  -0.0240  0.80   1.00 
         929   0.000  0.1080E-02    0.1463E-03  -0.0240  0.80   1.00 
           930 - 933 special fit.
         934  -0.014  0.1582E-02    0.1336E-03  -0.0297  0.80   1.00 
         935  -0.024  0.1664E-02    0.1146E-03  -0.0304  0.80   1.00
         936  -0.024  0.1664E-02    0.1146E-03  -0.0304  0.80   1.00 
         937  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         938  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         939  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         940  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         941  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         942  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         943  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         944  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         945  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         946  -0.020  0.1612E-02    0.1419E-03  -0.0300  0.80   1.00
         947  -0.006  0.1296E-02    0.2061E-03  -0.0236  0.80   1.00 
         948  -0.005  0.1300E-02    0.2061E-03  -0.0236  0.80   1.00
         949  -0.005  0.1300E-02    0.2061E-03  -0.0236  0.80   1.00
         950   0.007  0.9440E-03    0.3342E-03  -0.0105  0.80   1.00 
         951  -0.011  0.1433E-02    0.1654E-03  -0.0278  0.80   1.00  
         952  -0.011  0.1433E-02    0.1654E-03  -0.0278  0.80   1.00  
         953  -0.011  0.1433E-02    0.1654E-03  -0.0278  0.80   1.00  
         954  -0.011  0.1433E-02    0.1654E-03  -0.0278  0.80   1.00  
         955  -0.011  0.1433E-02    0.1654E-03  -0.0278  0.80   1.00  
         956  -0.011  0.1433E-02    0.1654E-03  -0.0278  0.80   1.00  
         957  -0.154  0.1608E-02    0.5058E-03  -0.0163  0.70   1.00 
         958  -0.014  0.1477E-02    0.1318E-03  -0.0289  0.80   1.00 
         959  -0.014  0.1477E-02    0.1318E-03  -0.0289  0.80   1.00 
         960  -0.014  0.1477E-02    0.1318E-03  -0.0289  0.80   1.00 
         961  -0.014  0.1477E-02    0.1318E-03  -0.0289  0.80   1.00 
         962  -0.019  0.1310E-02    0.1542E-03  -0.0240  0.80   1.00 
           963 - 969 special fit.  


         stn   bias     slope          pcor       tcor    wt    lag
         ---  ------  -----------   ----------  -------  ----   ----
         970   0.131  0.13908E-02  -0.9363E-03  -0.0277  0.80   1.00 
           971 - 979 special fit.  
         980  0.005   0.3081E-03    0.1529E-03  -0.0294  0.60   3.00  
         981  0.011   0.2968E-03    0.1529E-03  -0.0294  0.60   3.00 
         982  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         983  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         984  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         985  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         986  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         987  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         988  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         989  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         990  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         991  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         992  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         993  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         994  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         995  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         996  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         997  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         998  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         999  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         000  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         001  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         002  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         003  0.001   0.3028E-03    0.1569E-03  -0.0258  0.60   3.00
         004  0.0082  0.3217E-03    0.1485E-03  -0.0277  0.90   1.00
         005  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         006  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         007  0.018   0.2455E-03    0.2161E-03  -0.0205  0.60   3.00
         008  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         009  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         010  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         011  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         012  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         013  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         014  0.009   0.2903E-03    0.1476E-03  -0.0265  0.71   3.00 
         

"Special fit" indicates that a revised oxygen fitting algorithm was used for 
these stations.  See next section for details.


SPECIAL OXYGEN ALGORITHM FITTING

Fifty-three stations had the problem of fitting the CTD oxygen profile to the 
bottle data.  Bob Millard revised the oxygen algorithm in an attempt to 
improve the oxygen data from ICTD stations with pressure dependent oxygen 
residuals using the original Owens & Millard oxygen algorithm:

                       oc = (ocr+lag*docr/dt)*slope+bias

Two changes to the oxygen algorithm of Owens & Millard (1985) result in the 
equation below:

                  ox = oc*oxsat* exp(tcor*(T+wt*(OT-T)+pcor*P)

First is the uncoupling of the temperature parameters in the exponential of 
the algorithm (tcor*wt).  This becomes particularly helpful if the oxygen 
temperature (OT) term does not have a valid calibration.  A new term 
involving the cross-term between pressure and temperature has been added to 
the algorithm as it picks up additional variance.  Note that the oxygen lag 
term is negative for a number of station groups listed in table 3 below.  In 
recognition of the inadequate performance of the oxygen sensor modules used 
for these stations, we opted for the best fit to the water sample oxygen data 
even though the terms may not be physically realistic. 

            ox = oc*oxsat* exp(tcor1*T+tcor2*OT+pcor*P+ptcor*P*T)

The following figures demonstrate how well the adjusted algorithm has done in 
fitting two station groups that could not be fit with the original algorithm.


Figure 5: Oxygen fitting with new algorithm: Stations 865 to 869: Original 
          fit shows distinct pressure dependent shape as opposed to fit with 
          new algorithm.
          (Above plots display differences of bottle to CTD oxygen ml/l by 
          pressure in decibars.)

Figure 6: Oxygen fitting with new algorithm:  Stations 912 to 922:  Fit with 
          new algorithm removes pressure dependent shape of residuals.
          (Above plots display differences of bottle to CTD oxygen ml/l by 
          pressure in decibars.)

Figure 7: Refit of station group 912 to 922  (notice that shallow station 918 
          rosette data are bad).

Figure 8: Refit of stations 930 to 933 in comparison to surrounding stations.


Table 3: OXYGEN DATA FITTING COEFFICIENTS FOR REVISED ALGORITHM

         The following is a table of coefficients used to scale the oxygen 
         data in the 53 stations that exhibited oxygen fitting problems.   
         Note that some of the terms (i.e. lag) are unrealistic; they do, 
         however, allow these data to be fit to the rosette water sample 
         values.  These are the data that could not be fit with the standard 
         oxygen algorithm.

         stn    bias     slope      pcor       tcor1     tcor2      lag      ptcor
         --- ---------  --------  --------  ---------  ---------  ------  -----------
         860 -0.007971  0.001741  0.000156  -0.118095   0.050579   -4.17  -0.00006604
         861 -0.007971  0.001741  0.000156  -0.118095   0.050579   -4.17  -0.00006604
         862 -0.007971  0.001741  0.000156  -0.118095   0.050579   -4.17  -0.00006604

         865  0.016388  0.001236  0.000163  -0.027216  -0.007340   -0.82  -0.00003362
         866  0.016388  0.001236  0.000163  -0.027216  -0.007340   -0.82  -0.00003362
         867  0.016388  0.001236  0.000163  -0.027216  -0.007340   -0.82  -0.00003362
         868  0.016388  0.001236  0.000163  -0.027216  -0.007340   -0.82  -0.00003362
         869  0.016388  0.001236  0.000163  -0.027216  -0.007340   -0.82  -0.00003362

         880  0.157432  0.000496  0.000439   0.077879  -0.080973   -3.74  -0.00011072

         881  0.052984  0.000207  0.001009   0.073267  -0.044510  -11.85  -0.00010797
         882  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         883  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         884  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         885  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         886  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         887  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         888  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         889  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         890  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         891  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038
         892  0.046955  0.001134  0.000207  -0.011526  -0.015070    0.03  -0.00004038

         912  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         913  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         914  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         915  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         916  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         917  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         918  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         919  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         920  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         921  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167
         922  0.018098  0.001265  0.000161  -0.011542  -0.016859   -0.84  -0.00002167

         930 -0.028873  0.001555  0.000177  -0.016931  -0.010603   -5.01  -0.00003549
         931 -0.028873  0.001555  0.000177  -0.016931  -0.010603   -5.01  -0.00003549
         932 -0.028873  0.001555  0.000177  -0.016931  -0.010603   -5.01  -0.00003549
         933 -0.028873  0.001555  0.000177  -0.016931  -0.010603   -5.01  -0.00003549

         963 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067
         964 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067
         965 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067
         966 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067
         967 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067
         968 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067
         969 -0.013299  0.001418  0.000157  -0.009204  -0.015968    1.10  -0.00002067

         971 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173
         972 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173
         973 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173
         974 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173
         975 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173
         976 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173
         977 -0.019304  0.001652  0.000148  -0.011510  -0.019372    1.83  -0.00004173

         978  0.411273  0.000324  0.000045   0.266932  -0.283316  102.98  -0.00008445
         979 -0.035108  0.001632  0.000151  -0.018120  -0.012538   -2.50  -0.00003505

The quality of the final oxygen data is documented by the residual plots 
below:


Figure  9: Leg 1: Differences between final calibrated down oxygen data and 
           rosette water sample   data.

Figure 10: Leg 2: Differences between calibrated down oxygen data and rosette 
           water sample data

Figure 11: Stations 978 and 979 demonstrate that there were times during the 
           cruise when the CTD was opened up and the oxygen current digitizer 
           changed, resulting in a scaling change.


The following notes document instances where the quality word flag of the CTD 
oxygen in the CTD downtrace files was changed to 4 to signify bad data.

Stations 920-922, 915, 918: 
         Set flag of 1st oxygen value to 4 because oxygen current value is low 
         by 0.8 ml/l.
Station  858: Oxygen bad between 237 to 241 and 275 dbars; set quality word =4.
Station  978: From the surface to 71 dbars the CTD oxygen is flagged bad.


Figure 12: Station 978 oxygen data unsalvageable above 71 dbar.



DATA PROCESSING DETAIL NOTES:

STATION 863:
Made the internally recording (IR) backup CTD, CTD 1338, the primary data for 
the station instead of CTD 9.  CTD9's oxygen and salinity in the down profile 
were bad due to noisy pressure requiring heavy interpolation.  ICTD 1338 data 
were used to make the down 2-dbar file.  CTD 9's info was left with the 
bottle file. There were problems making the bottle file from the IR CTD.  
Note, there are different up and down cals, one for CTD1338, the other for 
CTD9.   

STATION 909:
ICTD1344 jumped in salinity by -0.002psu at 3453dbar.  Profile continued down 
at this lower salinity until reaching the bottom when it jumped back 
+0.001psu.  The uptrace bottles and surrounding stations did not support this 
feature.  The salinity below 3453 was replaced with the uptrace salinity. 

STATIONS 973 to 979:
ICTD 1344 conductivity sensor was jumping low, away from the profile and then 
back to the real value over these set of stations.  The problem appeared to 
be a loose mounting on the conductivity sensor that was epoxied into place 
after station 981.

STATION 973:
Replaced the bad downtrace salinity with uptrace salinity over the pressure 
ranges 1191 to 1641 dbar and 1707 to 2747 dbar.  

STATION 974:
Replaced the bad downtrace salinity with uptrace salinity over the pressure 
range 1921 to 3773 dbar (bottom).

STATION 975:
Large interpolations over bad sections. The ranges are listed in the 
interpolation file:
Station, Start pressure, 3=salinity, Ending pressure 
975,939,3,1127
975,1447,3,1453
975,1455,3,1457
975,1479,3,1485
975,1781,3,1833
975,2083,3,2157

STATION 976:
Interpolate over the bad section. The range is listed in the interpolation 
file:
Station, Start pressure, 3=salinity, Ending pressure
976,2191,3,2251

STATION 977:
Leave as is, there is some odd shape in the 900 to 1100 dbar range but it is 
loosely mimicked by the uptrace.

STATION 979:
Interpolate over bad section.  The range is 2683 to 3151 dbar. There is some 
shape in the 800 to 1200 dbar section but again, it is loosely copied by the 
uptrace data. 

STATION 978, 980 to 014:
ICTD1338 downtrace salinity was fit to bottles for downtrace scaling term. 
Uptrace left as it was.  There are two cal files for each station, one for 
uptrace data *.CU8 and one for downtrace data *.C08. 

The *.CTD files of 2 dbar pressure averaged and centered downtrace profiles 
and the *.SEA bottle file both refer to stations 1000 to 1014 as 0 to 14.
The *.SEA files (one for leg1 and one for leg2) have been updated with new 
CTD pressure, temperature, potential temperature, salinity and oxygen data 
produced from the latest set of calibration coefficients.
Final nutrient data has been merged into the *.SEA files as well.

A distinct processing sequence of events occurred after rescaling oxygen data 
for the 53 "problem oxygen " stations.
 
The following was done using Matlab:
1. The WOCE format files submitted in July 1998 were the starting point.
2. For those stations requiring revised CTD oxygen data, the new oxygen data 
   were overwritten into the original files.
3. The original CTD oxygen data in the SEA file were also overwritten with 
   the newest oxygen data.

The bottle file pressures were used to merge the 2 dbar down-profile CTD 
oxygen data from the stations      reprocessed into the bottle file.  

The SEA file was also put through an initial pass at setting quality flags 
for both CTD salt and oxygen:

The quality word of both the CTD oxygen and CTD salinity were compared to the 
bottle values using             a screening criteria that varied with 
pressure.  

Within the following pressure levels, differences abs(Oxw-Oxcw) exceeding the 
value given are marked questionable.

  Pressure less than 500 dbars Dox > 0.5 ml/l.
  Pressure between 500 and 1500 dbars Dox > 0.2 ml/l.
  Pressure greater than 1500 dbars and Dox > 0.1 ml/l.

All CTD oxygen values equal to -9.0 have had their quality word set equal to 9.

The original bottle file I1A.SEA had newly calibrated down CTD oxygen data 
merged into it and CTD salinity and oxygen data quality control edited.  The 
resultant file is I1AA.SEA.

The original bottle file I1B.SEA was output to file I1BB.SEA.    
The file I1B.SEA had a second set of four header records that were found to 
be inserted between station 999 and 0 (ie, station 1000).  These headers were 
removed from file I1aa.SEA.


RESOLVED DATA ISSUES:

Concern over possible pressure hysteresis in ICTD 1338 found to be caused by 
internal wave signal. 
      Issue was looked at by Bob Millard and determined not to be instrumen-
      tal hysteresis but the signal of vertical heaving by internal waves. 

Non-compliant IOS standard water, batch P-124 from box 2.
      Standard water believed to be .002 fresh. Problem recognized 
      immediately, only two stations resulted in questionable water sample 
      salts from using this batch of standard water. 

Spikes and jumps in all data fields throughout the cruise caused extensive 
editing.
      The entire dataset has been edited and spikes, jumps, etc have been 
      removed.

Pre- to post-cruise laboratory temperature calibrations of CTD 1344 and CTD 
1338 showed changes. 
      A combined pre and post cruise temperature calibration has been 
      selected for the ICTDs as described in the calibration summary section.

Oxygen fitting problems due to oxygen sensor failures and change-outs.
      Several factors slowed the CTD oxygen fitting.  Poor quality oxygen 
      sensors necessitated frequent changes of sensors: 7 changes total. This 
      resulted in at least as frequent changes in oxygen calibration 
      coefficients.  Swapped oxygen assemblies for stations 859 to 862 
      altered the oxygen temperature calibrations, another complication to 
      the data fitting.  Concentrations at the oxygen minimum come close to 
      zero for 35 stations.  It took substantially more time than usual to 
      find a calibration that resulted in CTD oxygen data consistent with the 
      water sample data but without going negative.

      As noted in the oxygen calibration section, a revision to the Owens-
      Millard algorithm was tried and found to provide an acceptable fit for 
      the oxygen data for 53 stations that were previously not able to be fit 
      with the original algorithm.

CTD equipment failures caused extra processing to fit data to water samples 
and improve data.
      Stations that had trouble with the primary instrument took extra time 
      to correct.  Such trouble includes segments of unreadable data or 
      individual sensors not responding.   Because two CTDs were usually on 
      the frame, along with a second, independent temperature sensor, these 
      problem stations were recovered by using data from the other 
      instrumentation.  For example, in the case of station 973, data from 
      both primary and backup was used to construct the final hydrographic 
      profile. 


REFERENCE:

Owens, W. B. and R. C. Millard Jr. (1985).  A new algorithm for CTD oxygen 
      calibration.  Journal of Physical Oceanography, 15, 621-631.



ATSEA.DOC
NOTES ON WORK DONE TO PARTICULAR STATIONS: EXTRACTS FROM AT-SEA WATCH-
STANDERS'  LOG HIGHLIGHTING DATA PROBLEMS AND FIXES.

Station 858: CTD 9
      Pressure dropout and cast aborted- no water samples.  CTD9 subsequently 
      found to have failed pressure sensor, apparently due to corrosion in 
      sensing element.  CTD cannot be fixed at sea.


Station 859: ICTD1344.  
      Pylon failure, at bottle 18 pylon homed itself with message error was 
      242.  Problem due to interfering telemetry of CTD and pylon.

AFTER Station 862: ICTD1338
      ICTD1338 opened to switch from FSK to memory mode, and will be used as 
      second CTD on frame.

Station 863: CTD9 with ICTD1338 in Memory mode.
      After Test station for CTD9, CTD 9 opened and found dessicant packs to 
      be caught btw boards, causing components on board to short out. Thought 
      was fixed, but everything dropped out twice during this station. 
      -USE ICTD1338 DATA FOR THIS STATION

Station 864:CTD12, 
      Test station for CTD12, after shipping got complete garbage trying to 
      run through seacable at 180 ma, switched to running at 250 ma seemed to 
      run fine on deck, so tried a test station.
      -down trace- cond jumps
      -uptrace- large TMR error that was counted as btl tags scan # 47614, 
      1297 dbar 55 btl tags 11-37 taken out, and 12

Station 865: ICTD1344
      with new oxygen sensor 5-06-03.
      CHANGED TO MKIII DECK UNIT ON UP CAST
      -a lot of noise in cast, changed over deck unit to MarkIII from FSI DT-
      1050, seemed to cleanup data.

Station 867:ICTD1344
      loss of signal during down cast, fsk was still there but pressure 
      pegged out at 6552. Put power supply in standby and switched to DT1050, 
      no response. Put power supply back in standby, swapped back to MKIII DU 
      and voila data returned.  
      CAST ABORTED
      Down trace- weird pressure jump in beginning of cast complete pressure 
      dropout at scans 26466-29569, 647 dbar

Station 869:ICTD1344
      on down trace pressure pegged at 6552, FSK ok. Tried powering down for 
      5 min then back up- no luck,  package brought back to 400m powered down 
      then back up- no luck.  Brought package to 200m powered down then 
      backup - no luck, Tried firing 3 btl- no effect.  
      CAST ABORTED- BROUGHT BACK TO SURFACE
      downcast- complete pressure drop out at 27832 used this as cut off scan 
      number in header.

After station 869:
ICTD1338 OPENED TO CHANGE TO FSK MODE

After station 870:
I     ICTD1344 opened up, found un-insulated wires, sloppy wiring.
      Problems repaired.  ICTD1344 memory card now installed.

      SALINOMETER 10 BLEW POWER SUPPLY, CHANGED OUT OK

After station 872: ICTD1338, ICTD1344 memory.
      ICTD1344 SURGERY, ICTD OPENED.  Power board replaced with spare.

Station 875:ICTD1338
      fter finished station tried to send pylon home, received
              comm errors, pylon draws .280 A, pylon trying to move 
              to home, but seemed stuck, helped move and washed out, 
              pylon them seemed to be ok, drew .1 A.

Station 884:ICTD1338
            -down trace PRESSURE JUMP
                        pressure jumped from 5.9 to 7.7 and did not jump
                        back. scan # 14458
                        interped btw 5.9 dbar.
            -uptrace- cast started on deck and not erased
                     fast temperature jump

Station 886:ICTD1338
            -Pylon problems- computer return after firing 1 01 7
                                                          2 02 7
               tried to position to 3- comm error
               reinitialized and positioned to 2 success
            -CTD powered up at 0725

After station 888:
         ******ICTD1344 OPENED  ******
        ICTD not used since last opening to replace power board.
                    
After station 892:
******ICTD1344 AND ICTD1338 BOTH OPENED TO SWAP OUTMEMORY CARD*********

Station 900:ICTD1344, P1484, SIOSCI, MKIII DU, FRAME B
            ICTD 1338 INTERNALLY RECORDING
            Cast one aborted, sensor covers left on package
            CTD harness replaced and connectors re-greased, still
            a problem- a lot of synch errors from CTD
            Problem found to be in termination, swapped to port sea cable
            problem still continued. Turned off pylon power and synch error
            went away.

Station 907:ICTD1344
            MODEM CARD ON SIOSCI MODIFIED TO REDUCE
TRANSMIT LEVEL, HOPING
            TO AVOID SYNCH ERRORS- lower surf xmit

Station 910:ICTD1344
            NEW OXYGEN SENSOR 5-06-02

Station 913:BACKUP ICTD1338 ON FRAME, BUT NOT RECORDING
IN MEM MODE-
            bat died 

Station 915:BACKUP ICTD1338 INTERNALLY RECORDING- new
battery
            -down trace-clean

Station 923:ICTD1344
            NEW OXYGEN SENSOR (5-07-02)
            FAWL CONNECTOR ON IRICTD1338 FAILED, ICTD1338
WAS REMOVED AND
            A 3 PIN BULKHEAD CONNECTOR WAS PUT IN PLACE.


Station 925:ICTD1344
            ICTD1338 INTERNALLY RECORDING, POWERED DOWN
SEACABLE
            PORT SEACABLE
            lots o' synch errors, pylon turned off during down trace
            winch stopped at 4350 dbar to check level wind of winch
            pylon problems trying to fire bottle 35, tried turning off and
            on pylon, reinitializing it, kept saying 02 7. When brought on
            deck found pylon to be at position 7. Reinitialized on deck
            and seemed to work fine.
            -down trace- very noisy in conductivity, fast temp, oxtemp jumps 
             pressure -150 jumps
             synch errors- 55 errors
            -uptrace- cleaned up only around btl tags
                      took out btl tag 33.

Station 903:ICTD1344
                NEW OXYGEN SENSOR 4-10-2

After station 942:
       *******CONDUCTIVITY SENSOR ON BOTH ICTD1338 AND 1344 WERE CLEANED*****
                                                 

Station 948:ICTD1344
            pylon problems in beginning of cast, reinitialized, retried
            re-initialized and retried again, worked on third attempt.

After station 955:
        *****PROBLEMS WITH INTERNALLY RECORDING ICTD1338*********

Station 958:ICTD1344
            BOTTOM CONTACT WITH PACKAGE
            pylon problems, comm errors with pylon, however all
            bottles were fired

After station 961:
************ICTD1338 UPDATED EEPROM VERSION 1.9SMF     *********
***********CHANGED OUT POWER SUPPLY AND PUT A NEW ONE IN*********
             

Station 973:ICTD1344
            PRIOR TO STATION TOOK OUT MECCA WYE, AND 2 PIN
CONNECTOR TO MECCA, CHANGED OUT THE HARNESS
 ****IN FINAL DATA USE ICTD1344 OXYGEN TRACE w/ ICTD1338
CONDUCTIVITY TRACE***
       STATION 973 *.prs file currently has oxygens from iCTD1344 and
       salts from IRICTD1338. M-file s973sal.m can be used to replace the
       the salt column from kj45d973.prs.
     
Station 975:ICTD1344
            PRIOR TO STATION, SWAPPED FSKICTD CONDUCTOR
TO MEM ICTD
            CONDUCTOR

Station 977:ICTD1344
            CLEANED CONDUCTIVITY SENSOR ON ICTD1344,
CHECKED FOR ROTATION
                     
Station 978: ICTD1344
  *****IN FINAL DATA SET USE IRICTD1338 DATA, THIS WAS DONE OCT95****
  **** ICTD1344 DATA BACKED UP ONTO POSTPROC DISKS AS WELL AS    ****
  **** ICTD1338 DATA                                             ****

Station 980: ICTD1344, ICTD1338 in Memory mode.
New oxgen sensor on ICTD1344 #4-12-04
ICTD1338 IN MEMORY w/ OTM 1372, POWER DOWN SEA CABLE.
For final dataset use ICTD1338 data - note this was done in Oct95.
ICTD1338 data backed up in POSTPR data, ICTD1344 only backed up raw 
data.
Water sample salts flagged as 3, appear to be .002 fresh, problem with 
standard water.

Station 981: ICTD1338
Water sample salts flagged as 3, appear to be 0.002 fresh, problem with 
standard water was subsequently found to be cause.

After station 981: ICTD1344
ICTD1344 FIRMWARE UPGRADED to version 1.9SMF providing 14 bits of 
oxygen digitization.
CONDUCTIVITY SENSOR STEM EPOXIED IN PLACE SO IT WILL NOT ROTATE.
OTM CHANGED TO VARIABLE 16, AND REDUNDANT TEMP TO VARIABLE 17,  TO 
MATCH PAST CRUISES.

Station 991: ICTD1344
IN MEMORY w/ OTM 1372- new oxygen sensor (5-06-01)
                   
Station 1005:ICTD1338
*****RECORD LAYOUT CHANGED TO INCLUDE PRSTEMP VAR#14****
Stopped cast at 1000m on down cast to see how pressure temp reacts, 
also stopped at approx 2750m.

Station 1012:ICTD1338,
             Fast thermistor stem is not tight, tech did not repair anything; 
damage might result.

                        = end of Watchstander's log =



CRUISE INTERPOLATION DOCUMENTATION

List of interpolations applied after the pressure averaging and centering.  
The columns are for station number, the starting bad pressure, the column to 
be interpolated over (3=salinity, 4=oxygen), and the ending bad pressure.  
This does not list the edits done to the raw data using the EG&G software's 
ctdpost editor.

                 SALINITY INTERPOLATIONS
                                         002  1291  3  1297
                                         002  1353  3  1367
                                         002  1405  3  1413
                                         005  2773  3  2779
                                         005  1001  3  1015
                                         005   881  3   885
                                         864  2407  3  2413
                                         872     9  3     9
                                         964  1995  3  1999
                                         964  2243  3  2255
                                         964  1127  3  1137
                                         964  1429  3  1435
                                         975   939  3  1127
                                         975  1447  3  1453
                                         975  1455  3  1457
                                         975  1479  3  1485
                                         975  1781  3  1833
                                         975  2083  3  2157
                                         976  2191  3  2251
                                         979  2683  3  3151
                                         986  1535  3  1545
                                         987   671  3   697
                                         987  1043  3  1051
                                         987  1395  3  1399
                                         988  1321  3  1328
                                         988  1419  3  1423
                                         990  1187  5  1195
                                         991  1241  3  1245
                                         995   937  3   947
                                         997  1755  3  1771
                                         999   921  3   931
                                         999  1063  3  1081
                 OXYGEN INTERPOLATIONS      
                                         984  2321  4  2341
                                         984  2559  4  2575
                                         984  2871  4  2885
                                         984  2981  4  2991
                                         984  3087  4  3091
                                         987  2717  4  2725
                                         988  2125  4  2131
                                         988  3357  4  3361
                                         989  2977  4  2983
                                         990  3353  4  3357



POST CRUISE PROCESSING DOCUMENTATION
(July 1998)


SUMMARY OF STATIONS

CTD 1338  857,863,870-892,978,980,981-1014
CTD 1344  859-862,865-869, 893-898,900-978
CTD 9     858
CTD 12    864,899


There are no bottle files for stations 858,867 and 869 due to the pressure 
signal having dropped out requiring the cast to be aborted. Station 859 had 
bottles up to 800db until a jellyfish got caught up in the pylon causing the 
pylon to home itself.


PRE V POST CALIBRATIONS

PRESSURE

ICTD 1338 changed by 1.5 db, chose to use an average of the pre and post 
cruise cal.

 
TEMPERATURE

The ICTD 1344 temperature calibration changed pre to post cruise laboratory 
calibration with a bias shift of +.002 deg C. CTD reading warmer at the post 
cruise cal than at the pre cruise cal. The point at where the temperarture 
shift occured was looked for but not found.  The most reliable search was to 
look at same station primary and internal recording CTDs. They did not show 
where the jump occured. The fast thermister's were also compared and points 
where the salinity cal changed. There was not enough proof to point to a spot 
where the jump occured so instead an average of the pre and post cruise 
calibrations was used to process the data.

ICTD 1338 had a small change, less than .002 deg C. The pre and post 
temperature cal were averaged to be used with the post cruise processing. 


SALT

Plot results of deep water revealed that there was a CTD dependent bias: 
1338: *.PRS CTD salt read too high ~.002psu or temperature was too low 
compared to *,SEA file. 1344: *.PRS CTD salt read too low ~.001 psu or 
temperature was too high compared to *.SEA file. The consistancy of the bias 
between stations indicates it was probably not a real ocean measurement such 
as measuring internal waves, but some kind of instrument, package dynamic or 
bottle artifact.

All ICTDS 1338 stations have a sig. bias, with the downtrace always saltier 
than the bottles. The uptrace has been fit well, but the uptrace is fresher 
than the downtrace. To correct for the difference, the downtrace salinity, 
the group of station 978 to 1014, was fit to the bottle data. The results 
looked good. The earlier group of 1338 stations seemed to fit well after 
forcing the bottom bottles to be met by the CTD so were not refit using the 
downtrace.

ICTD 1344 downtrace trends toward being fresher than the bottles. The uptrace 
and downtrce agree, but the fits were not working well. Rework some of the 
fits, concentrating on matching up the CTD and salts in the bottom water.

CTD comparisions were made with the primary and backup data from the same 
stations. Pressure agreed very well, bottom depths were within 1db on the 
stations checked. Temperature would stray, +/-.002 at the bottom, sometimes 
ictd 1338 being warmer, sometimes ictd 1344. probably a factor of where they 
were located on the frame.

Stations 936-938,940-941
A Pressure dependant shape could not be removed without changing beta (and 
alpha) conductivity terms. After station 942, the conductivity cell was 
cleaned although no specific reason is given. The difficult calibrations from 
station 936 to 942 could have been induced by fouling or buildup on the 
conductivty cell. Stations 936, 937 and 938 have BETA changed from 1.5e-8 to 
.75e-8 Stations 940 and 941 have BETA changed from 1.5e-8 to .75e-8 and ALPHA 
changed from -6.5e-6 to -9.75e-6.

Station 923 and 954 both have salt changes that looked questionable until the 
uptrace was overlaid and followed the shape of the downtrace. Station 923 
freshens around 2 deg C. Station 954 has spikes and a shift at 1750db, 1900db 
and 2250 db that are clearly repeated in the uptrace. 


OXY

The oxygen temperture (OT) coefficients were changed for the post processing. 
Found that there were several instances of the CTD profile not reaching the 
oxygen minimum, or overshooting the minimum. This may have been due to not 
having the proper OT coefficients so decided to remake calibrations files 
that have the proper pre cruise OT coefficients for each CTD. 

OT coefficient changes:

      Sta, Apply to,         Change made
      ---- ----------------  ------------------------------------------
      857  857,870-892       replaced wrong 38 bias with right 38 bias.
      859  859-862           replaced 38 OT cal with 44 OT cal.
      865  865-869           left as is.
      893  893-979 x899,978  replaced 38 OT +wrong bias with 44 OT cal.
      978  978               replaced wrong 38 bias with right 38 bias.
      980  980               replaced wrong 38 bias with right 38 bias.
      981  981-004           replaced wrong 38 bias with right 38 bias.
      005  005-014           replaced wrong 38 bias with right 38 bias.

Stations 859 to 862 were taken with ICTD 1344 but used ICTD1338's oxygen 
assembly. 44's ot term were put into the cal file.


FITTING

Some stations fit just fine and others had a definate pressure dependant 
shape in the residuals. It was a similar shape that reoccured in different 
groups. The shape was more pronounced in some groups than others.  A weight 
of .8 and lag of 1 was consistant from a few of the larger groups. Most of 
the groups had this weight and lag held during the fits since many groups 
came up with weights over 1 and lags below 0 when allowed to fit for those 
parameters. For the groups with the pressure dependant shape in the 
residuals, tcor was held at some value lower than the fit originally came up 
with. Usually tcor was adjusted -.002 and the group refit. The resulting 
residuals between 2000 to 5000 db would be centered around 0 with a spread 
reduced from +/-.1 to +/-.04 but the shape would remain in the upper 2000 db. 

Groups with the pressure dependant shape:

                                   859-862
                                   865-869
                                   911-922
                                   930-933
                                   934
                                   935
                                   937-946
                                   962-969
                                   971-979

Stations 877,878,879 and 004 were scaled using the atsea ot and oc terms. 
With the new OT, it was not possible to get as good a fit as the atsea 
results. The terms arrived at had unrealistic numbers such as a negative lag 
but was used anyway for the resulting good fit.

50 stations had the problem of fitting to the top water or fitting to the 
bottom but not both at once. Bob Millard agreed to try his method of coming 
up with two fits for a single station and then blend them together at the 
middle. The stations have '4's (bad) in the quality word of the CTD files. 

The stations are: 
                                   859,861-862
                                   865-869
                                   880-881
                                   882-892
                                   912-922
                                   933
                                   963-969
                                   971-977
                                   978-979


Stations 857-858, test stations, had the oxygen quality word flagged '4' 
(bad) in the downtrace. All the bottles were deep and not useful for finding 
a fit for the whole profile.

Station 859, the next station in the same locations as 857 and 858, had 
bottles except for the top 800db due to a pylon failure. Even with a better 
fit this top should be labeled '3' (questionable).

Station 860, a test station for water sampling. The downtrace oxygen was 
labeled '4' due to all bottles fired deep.

Stations 906 to 904 have clear shape in the bottom water that may or may not 
be real. The uptrace looks as if it follows the shapes loosely, not really 
until the larger features aroud 2000db does it really follow the downtrace. 
Station 937 had extra bottles taken deep to watch the +/- .05ml/l variation 
in oxygen. The bottles do look like they agree with the oxygen. 

Station 987, a -.04 ml/l shift in oxygen at 2711db does not look real, and 
does not agree with bottle or following stations. It has been flagged '3' 
(questionable).



NOTES ON WORK DONE TO PARTICULAR STATION:

STATION 863 
Made the internally recording (IR) backup CTD, CTD 1338, the primary data for 
the station instead of CTD 9. CTD9's oxygen and salinity in the down profile 
were bad due to noisy pressure requiring heavy interpolation. ICTD 1338 data 
was used to make the down 2-db file. CTD 9's info was left with the bottle 
file. There were problems makeing the bottle file from the IR CTD. Note, 
there are different up and down cals!, one for CTD1338, the other for CTD9. 

STATION 909 
CTD1344 had jumped in salinity -.002psu at 3453db. Profile continued down at 
this lower salinity until reaching the bottom it jumped back +.001psu. The 
uptrace, bottles and surrounding stations did not support this feature. The 
salinity below 3453 was replaced with the uptrace salinity. 

STATIONS 973 to 979
CTD 1344 conductivity sensor was jumping low, away from the profile and then 
back to the real value over these set of stations. The problem appeared to be 
a loose conducivity sensor that was epoxied into place after station 981.

STATION 973 
Replace the bad salinity with uptrace salinity over the pressure ranges 1191 
to 1641 db and 1707 to 2747 db.

STATION 974 
Replace the bad salinity with uptrace salinity over the pressure range 1921 
to 3773 db (bottom).

STATION 975 
Large interpolations over bad sections. The ranges are listed in the 
interpolation file: Station, Start pressure, 3=salinity, Ending pressure

                                975,939,3,1127
                                975,1447,3,1453
                                975,1455,3,1457
                                975,1479,3,1485
                                975,1781,3,1833
                                975,2083,3,2157

STATION 976 
Interpolate over the bad section. The range is listed in the interpolation 
file:
     Station, Start pressure, 3=salinity, Ending pressure 976,2191,3,2251

STATION 977 
Leave as is, there is some odd shape in the 900 to 1100 db range but it is 
loosley mimicked by the uptrace .

STATION 979 
Interpolate over bad section. The range is 2683 to 3151 db. There is some 
shape in the 800 to 1200 dbar section but again, it is loosely copied by the 
uptrace data.


STATION 978, 980 to 014 
CTD1338, the downtrace salinity was fit to bottles for downtrace scaling 
term. Uptrace left as it was. There are two cal files for each station, one 
for uptrace data *.CU8 and one for downtrace data *.C08. 

The *.CTD files of 2 db pressure averaged and centered downtrace profiles and 
the *.SEA bottle file both refer to stations 1000 to 1014 as 0 to 14.

The *.SEA files (one for leg1 and one for leg2) have been updated with the 
new CTD pressure, temperature, potential temperature, salinity and oxygen 
data produced from the latest set of calibration coefficients. The indivdual 
quality of the CTD salt and oxygen observations within the *.SEA file has not 
been checked. The quality words for these two parameters has been left as '3' 
(questionable) simply to show they have not been looked at.  

Final nutrient data has been merged into the *.SEA files as well.





_________________________________________________________________________________________________________
_________________________________________________________________________________________________________





BOTTLE DATA

CFC-11 and CFC-12 Measurements - WOCE I1

Leg 1: Muscat, Oman to Colombo, Sri Lanka
       Analysts: Mr. Steven Covey, University of Washington             
                 Ms. Sabine Mecking, University of Washington

Leg 2: Colombo, Sri Lanka to Singapore
       Analysts: Mr. Steven Covey, University of Washington             
                 Ms. Wenlin Huang, University of Washington 


SAMPLE COLLECTION AND ANALYSIS

Samples for CFC analysis were drawn from the 10-liter Niskins into100-cc 
ground glass syringes fitted with plastic stopcocks.  These samples were the 
first aliquots drawn from the particular Niskins.  The samples were analyzed 
using a CFC extraction and analysis system of Dr. Ray F. Weiss of Scripps 
Institution of Oceanography. The analytical system was set up in a portable 
laboratory, belong to Dr. John Bullister, on the fantail of the R/V Knorr.  
The analytical procedure and data analysis are described by Bullister and 
Weiss (1988).  One syringe, Becton-Dickinson9882, was found to be a source of 
contamination for CFC-11. A separate sampling blank was applied to this 
syringe.  These samples have been flagged as "questionable" (WOCE flag 3) and 
are listed below (Table 4).  The CFC concentrations in air (Table 3) were 
measured approximately every two days during this expedition.  Air was pumped 
to the portable laboratory from the bow through Dekabon tubing.  


Calibration

A working standard, calibrated on the SIO1993 scale, was used to calibrate 
the response of the electron capture detector of the Shimadzu Mini-2 GC to 
the CFCs.  This standard, Airco cylinder CC88110, contained gas with CFC-11 
and CFC-12 concentrations of 275.61 parts per trillion (ppt) and 496.49 ppt, 
respectively. 


SAMPLING BLANKS

We have attempted to estimate the level of contamination by taking the mode 
of measured CFC concentration in samples which should be CFC-free.  In this 
region, measurements of other transient tracers such as carbon-14 indicate 
that the deep waters are much older than the CFC transient. We have used all 
samples deeper than 2000 meters to determine the blanks of 0.002 picomoles 
per kilogram (pmol/kg) for CFC-12 and 0.004 pmol/kg for CFC-11.  These 
concentrations have been subtracted from all the reported dissolved CFC 
concentrations.  Syringe 9882 had a much higher sampling blank for CFC-11 
(0.010 +/- 0.010 pmol/kg) based on the mean of a few samples. Since there is 
a large uncertainty in the contamination level, all of the samples collected 
using this syringe during the first leg have been flagged as questionable.  
The stopcock (likely source of the contamination) appears to have been 
changed for leg 2.


DATA

In addition to the CFC concentrations which have merged with the .hyd file, 
the following three tables have been included to complete the data set.  The 
first two are tables of the duplicate samples. The third is a table of the 
measured atmospheric CFC concentrations listed with time and position. 


Table 1: CFC-11 Concentrations in Replicate Samples

         STN  SAMP    CFC-11   WOCE        STN  SAMP    CFC-11   WOCE
         NBR  NO.     pM/kg    Flag        NBR  NO.     pM/kg    Flag
         ---  ----  ---------  ----       ----  ----  ---------  ----
         859   1    10  0.003   2          899   1     1  0.003   2
         859   1    10  0.007   2          902   1    16  0.208   2
         862   1    24  0.812   2          902   1    16  0.211   2
         862   1    24  0.822   2          909   1    21  0.026   2
         863   1    25  0.100   2          909   1    21  0.025   2
         863   1    25  0.098   2          912   1     9 -0.004   2
         864   1    15  0.135   2          912   1     9 -0.001   2
         864   1    15  0.136   2          925   1     2  0.000   2
         866   1    25  0.972   2          925   1     2  0.000   2
         866   1    25  0.965   2          925   1    21  0.005   2
         870   1    12  0.071   2          925   1    21  0.003   2
         870   1    12  0.072   2          929   1     1  0.008   2
         871   1    19  0.402   2          929   1     1  0.008   2
         871   1    19  0.410   2          936   1    24  0.010   2
         872   1    20  0.816   2          936   1    24  0.013   2
         872   1    20  0.830   2          940   1    29  0.355   2
         873   1     1  0.661   2          940   1    29  0.348   2
         873   1     1  0.670   2          941   1     1  0.000   2
         877   1    17  0.701   2          941   1     1  0.002   2
         877   1    17  0.703   2          952   1    16  0.010   2
         885   1    20  0.501   2          952   1    16  0.014   2
         885   1    20  0.492   2          954   1     5 -0.002   2
         889   1    15  0.147   2          954   1     5 -0.003   2
         889   1    15  0.146   2         1012   1     7  1.441   2
         899   1     1  0.002   2         1012   1     7  1.425   2


Table 2: CFC-12 Concentrations in Replicate Samples

         STN  SAMP    CFC-12   WOCE        STN  SAMP    CFC-12   WOCE
         NBR  NO.     pM/kg    Flag        NBR  NO.     pM/kg    Flag
         ---  ----  ---------  ----       ----  ----  ---------  ----
         889   1    15  0.078   2          896   1    33  1.012   2
         896   1    33  1.006   2          899   1     1 -0.002   2
         859   1    10  0.005   2          899   1     1 -0.002   2
         859   1    10  0.011   2          902   1    16  0.111   2
         862   1    24  0.476   2          902   1    16  0.111   2
         862   1    24  0.482   2          909   1    21  0.014   2
         863   1    25  0.054   2          909   1    21  0.013   2
         863   1    25  0.044   2          912   1     9  0.000   2
         864   1    15  0.070   2          912   1     9 -0.002   2
         864   1    15  0.070   2          925   1     2  0.002   2
         866   1    25  0.543   2          925   1     2  0.002   2
         866   1    25  0.545   2          925   1    21  0.004   2
         868   1    22  0.186   2          925   1    21  0.000   2
         868   1    22  0.172   2          929   1     1  0.003   2
         870   1    12  0.034   2          929   1     1  0.001   2
         870   1    12  0.038   2          936   1    24  0.004   2
         871   1    19  0.220   2          936   1    24  0.007   2
         871   1    19  0.224   2          940   1    29  0.188   2
         872   1    20  0.429   2          940   1    29  0.184   2
         872   1    20  0.427   2          941   1     1  0.001   2
         873   1     1  0.370   2          941   1     1  0.000   2
         873   1     1  0.380   2          952   1    16  0.006   2
         877   1    17  0.395   2          952   1    16  0.006   2
         877   1    17  0.392   2          954   1     5  0.001   2
         885   1    20  0.275   2          954   1     5 -0.001   2
         885   1    20  0.266   2         1012   1     7  0.840   2
         889   1    15  0.080   2         1012   1     7  0.831   2


Table 3: Atmospheric CFC Concentrations

         AIR  LAT N   LON E    DATE   TIME  CFC-11  CFC-12  STNNBR
         NBR   deg     deg     gmt    gmt    ppt     ppt   (approx.)
         ---  ------  ------  ------  ----  ------  ------  -------
           1  19.082  58.797  950831   657   262.0   526.2    861 
           1  19.082  58.797  950831   707   261.9   523.8    861 
           1  19.082  58.797  950831   717   261.5   527.3    861 
           1  19.082  58.797  950831   726   262.1   528.8    861 
           2  16.267  56.555  950901   825   262.2   527.0    863 
           2  16.267  56.555  950901   840   262.6   527.3    863 
           2  16.267  56.555  950901   850   262.6   525.8    863 
           2  16.267  56.555  950901   900   262.4   523.7    863 
           2  16.267  56.555  950901   918   262.1   522.5    863 
           3  14.167  52.753  950903  1001   262.0   523.9    870 
           3  14.167  52.753  950903  1010   262.0   521.4    870 
           3  14.167  52.753  950903  1020   261.9   523.3    870 
           3  14.167  52.753  950903  1029   261.8   523.5    870 
           4  12.375  43.812  950905  1721   266.0   531.1    873 
           4  12.375  43.812  950905  1730   264.8   531.2    873 
           4  12.375  43.812  950905  1740   265.2   529.7    873 
           4  12.375  43.812  950905  1749   265.1   532.7    873 
           5  12.333  45.753  950906   904   263.9   531.0    877 
           5  12.333  45.753  950906   914   263.6   530.9    877 
           5  12.333  45.753  950906   923   263.7   529.3    877 
           5  12.333  45.753  950906   933   263.7   528.5    877 
           6  13.065  48.568  950907  1701   265.3   536.2    883 
           6  13.065  48.568  950907  1711   264.6   536.0    883 
           6  13.065  48.568  950907  1720   264.7   533.4    883 
           7  13.717  51.568  950909  1118   262.6   523.5    892 
           7  13.717  51.568  950909  1128   261.6   523.1    892 
           7  13.717  51.568  950909  1137   262.7   522.5    892 
           7  13.717  51.568  950909  1147   262.3   523.4    892 
           8   9.898  53.800  950911    32   262.8   524.7    897 
           8   9.898  53.800  950911    43   261.5   521.1    897 
           8   9.898  53.800  950911    52   261.9   522.3    897 
           8   9.898  53.800  950911   102   261.4   521.8    897 
           9   8.823  52.690  950913   802   261.9   525.6    904 
           9   8.823  52.690  950913   812   261.8   525.0    904 
           9   8.823  52.690  950913   822   261.6   523.9    904 
           9   8.823  52.690  950913   832   262.3   524.4    904 
          10   8.930  54.417  950914  1151   262.6   523.6    908 
          10   8.930  54.417  950914  1201   262.5   523.8    908 
          10   8.930  54.417  950914  1212   262.3   524.7    908 
          11   8.490  58.110  950916   603   262.0   525.5    916 
          11   8.490  58.110  950916   613   262.1   523.6    916 
          11   8.490  58.110  950916   624   262.3   523.4    916 
          11   8.490  58.110  950916   634   262.2   523.1    916 
          12   9.008  61.552  950918   941   262.4   524.5    925 
          12   9.008  61.552  950918   951   263.1   525.6    925 
          12   9.008  61.552  950918  1001   263.1   525.7    925 
          12   9.008  61.552  950918  1010   263.5   524.9    925 
          13   8.500  65.883  950921   258   262.9   528.6    934 
          13   8.500  65.883  950921   308   263.1   528.5    934 
          13   8.500  65.883  950921   318   263.1   526.4    934 
          13   8.500  65.883  950921   328   262.8   528.8    934 
          14   8.497  68.900  950922  2130   263.9   526.4    940 
          14   8.497  68.900  950922  2140   262.7   524.3    940 
          14   8.497  68.900  950922  2151   263.7   525.1    940 
          14   8.497  68.900  950922  2202   262.5   525.4    940 
          14   8.497  68.900  950924    40   261.9   520.6    940 
          14   8.497  68.900  950924    55   260.2   522.8    940 
          15   8.503  71.215  950924   130   262.7   528.6    944 
          15   8.503  71.215  950924   140   262.2   526.8    944 
          15   8.503  71.215  950924   149   262.0   525.0    944 
          15   8.503  71.215  950924   200   262.9   526.5    944 
          16   8.568  73.832  950925   906   262.9   525.4    951 
          16   8.568  73.832  950925   916   263.0   523.7    951 
          16   8.568  73.832  950925   926   262.7   526.5    951 
          17   6.417  79.100  950927  1418   263.7   527.1    958 
          17   6.417  79.100  950927  1428   263.7   526.7    958 
          17   6.417  79.100  950927  1438   264.0   526.7    958 
          18   5.633  79.997  950930  1242   262.9   529.2    963 
          18   5.633  79.997  950930  1251   261.5   528.3    963 
          18   5.633  79.997  950930  1301   262.7   526.9    963 
          19   9.963  83.847  951004  2220   265.1   532.5    978 
          19   9.963  83.847  951004  2231   264.8   530.5    978 
          19   9.963  83.847  951004  2241   265.0   528.9    978 
          19   9.963  83.847  951004  2252   264.4   530.6    978 
          20   9.828  86.788  951008   920   262.5   529.3    989 
          20   9.828  86.788  951008   930   264.1   531.8    989 
          20   9.828  86.788  951008   940   263.8   528.7    989 
          21   9.855  95.332  951012   230   263.2   526.8   1008 
          21   9.855  95.332  951012   239   263.6   526.2   1008 
          21   9.855  95.332  951012   250   262.8   525.0   1008 
          21   9.855  95.332  951012   302   263.1   526.2   1008 
          22   9.627  97.442  951013    21   263.9   530.7   1014 
          22   9.627  97.442  951013    30   263.9   528.9   1014 
          22   9.627  97.442  951013    41   264.1   527.8   1014 
          22   9.627  97.442  951013    53   263.8   526.7   1014 


Table 4 - Samples Collected Using Syringe 9882
          The following samples were collected with syringe 9882. Since deep 
          samples taken with this syringe showed some contamination, a higher 
          blank of 0.01 pmol/kg is subtracted from the samples collected 
          during the first leg of the cruise (up to station 861). All of the 
          samples from the first leg are also flagged as questionable (3) or 
          bad (4).

          NOTE: The sample number is 100*Cast plus the bottle number.

STN  SAMP  Nominal                   | STN  SAMP  Nominal  |  STN  SAMP  Nominal 
NBR        Depth                     | NBR        Depth    |  NBR        Depth  
---  ----  -------                   | ---  ----  -------  |  ---  ----  ------
857  127    3195                     | 912  122     700    |  958  127      30  
861  106    2600                     | 913  126     400    |  964  108    1350  
862  106    2000                     | 914  112    2400    |  965  128      90  
863  123     800                     | 915  123     250    |  966  128     350  
864  120     250                     | 917  110    2600    |  967  128     300  
868  122     300  % part of dupl.    | 918  114     800    |  968  128     350  
874  114     120                     | 919  116    1100    |  969  123     800  
879  127      30                     | 920  131      90    |  971  124     150  
881  110    1000                     | 921  124     500    |  972  125     450  
882  126      90                     | 922  136       5    |  974  128     150  
883  121     180                     | 923  119     800    |  975  114    1500  
884  114     600                     | 924  119    1100    |  976  129     250  
885  122     200                     | 925  101    4450    |  977  126     300  
887  116      20                     | 926  120    1100    |  979  129     150  
889  128       0                     | 927  121     100    |  980  125     350  
891  112     700                     | 928  101    4625    |  981  125     300  
892  136       5                     | 929  115    2000    |  986  110    2100  
893  110    2400                     | 930  116    1800    |  987  126     250  
894  110    2600                     | 931  119    1200    |  989  131     120  
895  128     300                     | 932  104    4200    |  990  114    1900  
896  133      90  % part of dupl.    | 933  125     600    |  991  128     120  
898  111    2800                     | 934  124     700    |  992  128     100  
899  109    3200                     | 935  108    3400    |  993  126     200  
900  119      60                     | 936  108    3700    |  994  122     450  
902  110    1100                     | 937  123     900    |  995  129      90  
903  123     600                     | 938  107    3700    |  996  122     450  
904  126     500                     | 941  135      30    |  997  122     600  
905  110    3400  % depth may be off | 948  124     165    |  998  126     200  
906  109    3800                     | 949  126      30    | 1000  112     150  
907  109    3600                     | 950  122      90    | 1002  113     350  
908  109    3800                     | 951  127     250    | 1003  128      90  
909  130     200                     | 952  108    1550    | 1004  126     500  
910  124     700                     | 953  126      90    | 1005  127     120  
911  109    3400                     | 955  110     800    | 1008  121     200  
                                     |                     | 1009  116     650  





_________________________________________________________________________________________________________
_________________________________________________________________________________________________________





DATA QUALITY EVALUATIONS


DQE OF WOCE I01E HYDROGRAPHIC DATA      
(Arnold W. Mantyla, Sept. 27, 2001)


This fall cruise started out with a short section south of Sri Lanka, 
repeating stations occupied six months earlier on I08; and then completed a 
section along 10N latitude across the southern Bay of Bengal and across the 
Andaman Sea. The Andaman Basin was quite uniform in characteristics and 
provided an excellent "calibration tank" for assessment of data precision. 
Salinity, oxygen and nutrients all easily met WOCE precision goals: salinity 
standard deviations to within .001 PSU, and oxygen and nutrient to better 
than 0.6%. In general, the data quality on this cruise was quite good. The 
following is a list of problems that were noticed, some of which may be 
corrected by the data originator.

I did not see any description in the DOC file on the analytical methods used 
to analyze the water sample salinity, oxygen or nutrient samples. Those 
descriptions should be added to the cruise documentation file.

1. Errors in the .sum file:
   Sta. 966 EN - had the wrong month and day - had 0930, changed to 1001 
   Sta. 1007 BO - latitude was 9 04.00 - changed to 9 54.00 

2. The CTD salinities and oxygens assigned to the bottle tip levels were 
   flagged as questionable on the last 29 stations. I understand that there 
   were problems with some of the CTD oxygen sensors and apparently the up 
   and down CTD salinity profiles had different offsets. However, from the 
   fairly consistent bottle minus up CTD salinity differences of just a few 
   thousandths, if appears that the up CTD salinities could be fixed to match 
   the bottle data reasonably well and accepted as ok. It is useful to have 
   good CTD salinity data for levels where the water sample salinity is 
   either missing or bad. Both T and S needed for density when O2 or 
   nutrients are used with respect to density surfaces.

3. The water sample salinities for stations 980 and 981 were all flagged 
   questionable, apparently on the basis of a presumed faulty ampule of 
   Standard Sea Water (P124). Comparison of the T/S curves for these stations 
   with a pair of stations to the west (979 and 985) and a pair of stations 
   to the east (986 and 987) showed differences of only about .001 to .002, 
   station 980 and 9891 slightly lower. Station 981 also agrees with the CTD 
   salinity to typically .001 except for samples 2 to 4, which appear to have 
   been drawn out of 1 bottle deeper than the depth assigned to the sample. I 
   suggest that station 981 salinities be accepted as ok, except for samples 
   2-4, which should be left as uncertain. On Station 980, the water samples 
   appear to be slightly low, while the CTD salinities appear to be slightly 
   high, but I would tend to accept the uncertain flags on the water samples 
   as done by the originators.

4. Twenty-seven different bottles were flagged as leakers at least once 
   during the cruise; but for the most part, the water samples appeared to be 
   ok and were not flagged. Bottles 1, 2, 23, 31, and 37 leaked more than 10 
   times. It would be of interest to know what caused the bottles to be 
   flagged and add a comment in the cruise documentation report noting what 
   was seen to result in such an unusually large number of leaking rossette 
   bottles.

5. Several stations had some nitrite data fields filled with "-9.00", but 
   with the data quality flag set to "2", meaning acceptable measurement. 
   I've changed those flags to "5" to indicate data not reported. (Stas. 
   972,976,992, and 993.)

6. Stations 982 to 985 were repeats or overlaps of stations 974 to 979. The 
   silicates on station 974 were about 4% higher than on sta. 982, both at 
   the same position. The silicate profile appeared to jump on sta. 973 and 
   then came back down on sta. 975. I suggest the data originators re-check 
   the standard factors compared to the other stations to see if there might 
   be a calibration error that resulted in the silicates being higher on 
   stas. 973 and 974. For now, I would consider the silicates for those two 
   stations to be questionable.

7. The bottom 12 silicates on sta. 996 appear to be high compared to adjacent 

   stations and also the nearby station from I09, sta. 234. Suggest flag them 
   uncertain unless the data originators can identify a problem with the end 
   calibration standard.

8. Although the oxygen precision was good in the Andaman Basin stations, 
   there are other indications that the oxygens might be suspect on this 
   cruise. On other cruises with more than one bottle tripped in the surface 
   mixed layer, the multiple trips agree to within the measurement precision 
   (O2 to within 0.5um/kg). Except for oxygen that was also true for the ten 
   or so stations on this cruise that had two bottles tripped in the mixed 
   layer. Here, the O2's differed by 3 to 8um/kg. Also, the I01E repeats of 
   I08 were high by about 4% (I01E higher). The mixed layer oxygen percent 
   saturation was also unusually high for this time of year, 107.5% +/-2.6%, 
   compared to historical values of 101 to 104%. Even a conversion error from 
   ml/l to um/l instead of um/kg would only result in a 2.5% error. I 
   recommend that the data originators re-check the ml/l to um/kg conversion 
   to verify the conversion was done correctly. As the data stands now, I 
   would regard the O2 data for this cruise as suspicious.

9. Station 969 has a temperature inversion of 0.02 deg. in the top 2 bottles 
   while the salinities are uniform, resulting in an instability. I recommend 
   the temperature calculations be re-examined to see if one might include a 
   spike in the average and a better value calculated.

10. Station 976: samples 8 and 9 O2 are about the same, while the CTD O2 
    profile shows a gradient. It appears that both O2 samples may have been 
    collected from the 8th bottle, so sample 9 was flagged "u".

11. Station 988: sample 8 salt and O2 are missing; the nutrients are unlikely 
    for this depth, so were flagged "u". 

12. Station 995: An O2 inversion at 401db was flagged "u", but the CTD O2 
    profile also shows an inversion at this depth, so it appears the O2 
    should be accepted as ok unless the originators have some other reason 
    for questioning that value. The bottle was not flagged as a leaker on 
    this station, although it was 13 other times on this leg.

13. Station 1004: Sample 36 at the surface clearly mistripped, the water 
    samples clearly are from some other depth. The oxygen and nutrients were 
    flagged "bad", but the bottle and salinity were accepted as ok. Both 
    should be flagged questionable as well.

14. Station 1005: Sample 23 salt and bottle flagged doubtful, but the O2 and 
    nutrients were accepted as ok. They should also be flagged "u".

15. Station 1009: The bottom salinity appears to be about .005 low and should 
    be "u'ed", it would be ok if the last 2 digits had mistakenly been 
    transposed.

16. Station 1010: From the silica profile compared to adjacent stations, it 
    appears that samples 5 and 6 both came from the number 6 depth, and 
    samples 3 and 4 were also assigned to one depth too deep. Therefore 
    samples 3, 4, and 5 nutrients were flagged "u". 




DQE OF WOCE I01W HYDROGRAPHIC DATA    
(Arnold W. Mantyla, Nov. 1, 2001)


This cruise started in the northwest Arabian Sea with a few stations along 
the coast of Oman; there they did a line of stations in the Gulf of Aden to 
the Red Sea entrance; followed by the main line of stations across the 
southern Arabian Sea from Somalia to India.

The first test station tripped all 36 bottles at about 3200db. The oxygen and 
nutrient precision were excellent, better than 0.5% S.D., but the salinities 
included a few poor samples that made the precision apparently not up to WOCE 
specifications. However, this station was early in the cruise and I suspect 
that inexperienced help may have resulted in a few sampling errors. The 
salinities for the majority of the cruise were fine. The overall data quality 
was generally quite good, except for some curiously poor mixed layer oxygens. 
The following text lists a few problems that were noticed during the data 
examination.

1. Problems in the .sum file:
   Many stations are listed with identical positions for the BE, BO, and EN 
   of a cast, and all 3 were coded as having been derived from a GPS fix. 
   Only the cast time closest to the GPS fix should have that code, the rest 
   that are assumed should have some other lower quality code, perhaps the 
   one for dead reckoning.

   Sta. 890 BE Position off by 1 deg. Changed to 14 deg. Sta. 927 BE 
   Position differs from BO and EN by 10'. Changed BE to agree with BO and 
   EN Sta. 941 BE, BO, and EN Dates off by one day, had 0922, changed to 
   0923.
2. The CTD salinities and oxygens assigned to the bottle trips have all been 
   flagged as "3, questionable measurement", or "1 analysis not received", 
   but data are listed for all trips. Should resolve the "1" flags on this 
   and on the following leg, as either OK or questionable.
3. Sta. 859 - NO DATA - 0-800db, all of the deep cast nutrients were poor, so 
   I flagged them as questionable. I suggest that the nutrient 
   standardization be re-checked to see if the data can be recovered. 

   Sta. 863, 2db: Surface temperature is bad, need to get a good one. 
   There are no flags for temperature. Should either get a good 
   temperature, or delete this one.

   Sta. 893 - There were 4 bottles tripped in the surface mixed layer, 
   with good agreement in all samples except for dissolved oxygen.  The 
   3rd one was 12 micro mols higher than the other 3, so I flagged it "u". 
   Station O2's seemed erratic at times on this and on the following leg 
   (see comment in the I01E DQE report).

   Sta. 899 and 900 - The surface temperatures are unlikely cooler than 
   the next depth down, while the salinities are uniform, resulting in 
   instabilities. The difference is 0.2 deg C on sta. 900. Suggest re-
   check surface temperatures to see if the average includes any spurious 
   data.

   Sta. 900, 499db - Double trip, data do not agree very well, "u'd" 
   bottle 5 data.

   Sta. 901, 33db - Temperature minimum, though salts are uniform 8 to 61 
   db. Suggest re-check temperature calculation, would "u" it if there 
   were a flag for temperature.

   Sta. 918 - Two trips at 5db, oxygens differ by 5%, can't tell which is 
   better, so left both as ok.

   Sta. 934 - 3 NO2's listed as -9.00, but flagged ok. Changed flag to not 
   reported. Problem occurs on other stations on this leg and on the next 
   leg as well. 

   Sta. 940 - Poor mixed layer O2 agreement, don't know which is most 
   likely, so accepted both as is.

   Sta. 943 - Deep silicates are unlikely high compared to other stations. 
   "u'd" the bottom 14 silicates, but suggest re-check end standard 
   calculations to see if these can be salvaged.

   Sta. 961 - Sample 1 was listed 13 times. Deleted 12 of them.





WOCE CTD Data Consistency Check: I01E

About the '_check.txt', '_sal.ps' and '_oxy.ps' files:

The WHP-Exchange format bottle and/or CTD data from this cruise have been 
examined by a computer application for contents and consistency. The 
parameters found for the files are listed, a check is made to see if all CTD 
files for this cruise contain the same CTD parameters, a check is made to see 
if there is a one-to-one correspondence between bottle station numbers and 
CTD station numbers, a check is made to see that pressures increase through 
each file for each station, and a check is made to locate multiple casts for 
the same station number in the bottle data. Results of those checks are 
reported in this '_check.txt' file. When both bottle and CTD data are 
available, the CTD salinity data (and, if available, CTD oxygen data) 
reported in the bottle data file are subtracted from the corresponding bottle 
data and the differences are plotted for the entire cruise. Those plots are 
the' _sal.ps' and '_oxy.ps' files. 

Following parameters found for bottle file:

EXPOCODE        SALNTY          CFC-12
SECT_ID         SALNTY_FLAG_W   CFC-12_FLAG_W
STNNBR          CTDOXY          TRITUM
CASTNO          CTDOXY_FLAG_W   TRITUM_FLAG_W
SAMPNO          OXYGEN          HELIUM
BTLNBR          OXYGEN_FLAG_W   HELIUM_FLAG_W
BTLNBR_FLAG_W   SILCAT          DELC14
DATE            SILCAT_FLAG_W   DELC14_FLAG_W
TIME            NITRAT          TCARBN
LATITUDE        NITRAT_FLAG_W   TCARBN_FLAG_W
LONGITUDE       NITRIT          ALKALI
DEPTH           NITRIT_FLAG_W   ALKALI_FLAG_W
CTDPRS          PHSPHT          CTDRAW
CTDTMP          PHSPHT_FLAG_W   THETA
CTDSAL          CFC-11
CTDSAL_FLAG_W   CFC-11_FLAG_W
   
  • All ctd parameters match the parameters in the reference station.
  • All stations correspond among all given files.
  • No bottle pressure inversions found.
  • Bottle file pressures are increasing.
  • No multiple casts found in bottle data.




WOCE CTD DATA CONSISTENCY CHECK: I01W

About the '_check.txt', '_sal.ps' and '_oxy.ps' files:

The WHP-Exchange format bottle and/or CTD data from this cruise have been 
examined by a computer application for contents and consistency. The 
parameters found for the files are listed, a check is made to see if all CTD 
files for this cruise contain the same CTD parameters, a check is made to see 
if there is a one-to-one correspondence between bottle station numbers and 
CTD station numbers, a check is made to see that pressures increase through 
each file for each station, and a check is made to locate multiple casts for 
the same station number in the bottle data. Results of those checks are 
reported in this '_check.txt' file.

When both bottle and CTD data are available, the CTD salinity data (and, if 
available, CTD oxygen data) reported in the bottle data file are subtracted 
from the corresponding bottle data and the differences are plotted for the 
entire cruise. Those plots are the' _sal.ps' and '_oxy.ps' files. 
Following parameters found for bottle file:

EXPOCODE        SALNTY          CFC-12
SECT_ID         SALNTY_FLAG_W   CFC-12_FLAG_W
STNNBR          CTDOXY          TRITUM
CASTNO          CTDOXY_FLAG_W   TRITUM_FLAG_W
SAMPNO          OXYGEN          HELIUM
BTLNBR          OXYGEN_FLAG_W   HELIUM_FLAG_W
BTLNBR_FLAG_W   SILCAT          DELC14
DATE            SILCAT_FLAG_W   DELC14_FLAG_W
TIME            NITRAT          TCARBN
LATITUDE        NITRAT_FLAG_W   TCARBN_FLAG_W
LONGITUDE       NITRIT          ALKALI
DEPTH           NITRIT_FLAG_W   ALKALI_FLAG_W
CTDPRS          PHSPHT          CTDRAW
CTDTMP          PHSPHT_FLAG_W   THETA
CTDSAL          CFC-11       
CTDSAL_FLAG_W   CFC-11_FLAG_W
   
  • All ctd parameters match the parameters in the reference station.
    Station #858 has a CTD file, but does not exist in i01w_hy1.csv.
    Station #867 has a CTD file, but does not exist in i01w_hy1.csv.
    Station #869 has a CTD file, but does not exist in i01w_hy1.csv.
    Station #882 exists in i01w_hy1.csv, but does not have a corresponding 
      CTD file.
  • No bottle pressure inversions found.
  • Bottle file pressures are increasing.
  • No multiple casts found in bottle data.







_____________________________________________________________________________________________________________
_____________________________________________________________________________________________________________









                                  APPENDIX A:

                        REPRINT OF PERTINENT LITERATURE




Johnson K.M., A.G. Dickson, G. Eischeid, C. Goyet, P.R. Guenther, R.M. Key,
K. Lee, E.R. Lewis, F.J. Millero, D. Purkerson, C.L. Sabine, R.G. Schottle,
D.W.R. Wallace, R.J. Wilke, and C.D. Winn. 2002. Carbon Dioxide, Hydrographic 
and Chemical Data Obtained During the Nine R/V Knorr Cruises Comprising the 
Indian Ocean CO2 Survey (WOCE Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, 
I10, and I2; December 1, 1994 -January 22, 1996), Ed. A. Kozyr. ORNL/CDIAC-138, 
NDP-080. Carbon Dioxide Information Analysis Center, Oak Ridge National 
Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee.





ORNL/CDIAC-138
NDP-080


           CARBON  DIOXIDE, HYDROGRAPHIC,  AND  CHEMICAL  DATA  OBTAINED
      DURING  THE  NINE R/V KNORR  CRUISES COMPRISING  THE  INDIAN OCEAN  CO2
    SURVEY (WOCE  SECTIONS I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, I10, and I2;
                       DECEMBER 1, 1994 JANUARY 19, 1996)


                                 Contributed by

        Kenneth M. Johnson,1   Andrew G. Dickson,2       Greg Eischeid,3   
        Catherine Goyet,4      Peter R. Guenther,2       Robert M. Key,5  
        Kitack Lee,6           Ernest R. Lewis,7         Frank J. Millero,6   
        David Purkerson,6      Christopher L. Sabine,8   Rolf G. 
        Schottle,9             Douglas W.R. Wallace,10   Richard J. Wilke,7 and 
                               Christopher D. Winn,11


 1  Department of Applied Science, Brookhaven National Laboratory, Upton, NY,
    U.S.A.  Retired, now at P.O. Box 483, Wyoming, RI, U.S.A.
 2  Scripps Institution of Oceanography, University of California, La Jolla, CA,
     U.S.A.
 3  Woods Hole Oceanographic Institute, Woods Hole, MA, U.S.A.
 4  University of Perpignan, Perpignan, France
 5  Department of Geosciences, Princeton University, Princeton, NJ, U.S.A.
 6  Rosenstiel School of Marine and Atmospheric Science, University of Miami,
    Miami, FL, U.S.A.
 7  Department of Applied Science, Brookhaven National Laboratory, Upton, NY,
    U.S.A.
 8  Pacific Marine Environmental Laboratory, NOAA, Seattle, WA, U.S.A.
 9  Department of Oceanography, University of Hawaii, Honolulu, HI, U.S.A.
10  Institute for Marine Sciences, Kiel, Germany
11  Hawaii Pacific University, Kaneohe, HI, U.S.A.




                                  Prepared by
                                Alexander Kozyr
                    Carbon Dioxide Information Analysis Center
                          Oak Ridge National Laboratory
                          Oak Ridge, Tennessee, U.S.A.

                          Date Published: October 2002

                                Prepared for the
                         Environmental Sciences Division
                  Office of Biological and Environmental Research
                            U.S. Department of Energy
              Budget Activity Numbers KP 12 04 01 0 and KP 12 02 03 0

                                Prepared by the
                    Carbon Dioxide Information Analysis Center
                          OAK RIDGE NATIONAL LABORATORY
                         Oak Ridge, Tennessee 37831-6335
                                   managed by
                                UT-BATTELLE, LLC
                                    for the
                            U.S. DEPARTMENT OF ENERGY
                          under contract DE-AC05-00OR22725



                                    CONTENTS

LIST OF FIGURES
LIST OF TABLES
ACRONYMS
ABSTRACT
PART 1:  OVERVIEW
1.  BACKGROUND INFORMATION
2.  DESCRIPTION OF THE EXPEDITION
     2.1  R/V Knorr: Technical Details and History
     2.2  The Indian Ocean CO2 Survey Cruises Information
     2.3  Brief Cruise Summary
3.  DESCRIPTION OF VARIABLES AND METHODS
     3.1  Hydrographic Measurements
          3.1.1 SIO/ODF Methods and Instrumentation
          3.1.2 WHOI Methods and Instrumentation
          3.1.3 Underway Measurements
     3.2  Total Carbon Dioxide Measurements
     3.3  Total Alkalinity Measurements
     3.4  Carbon Data Synthesis and Analysis
     3.5  Radiocarbon Measurements
4.  DATA CHECKS AND PROCESSING PERFORMED BY CDIAC
5.  HOW TO OBTAIN THE DATA AND DOCUMENTATION
6.  REFERENCES





LIST OF FIGURES (see PDF report for figures)

Figure

1  The cruise track during the R/V Knorr expeditions in the Indian Ocean along
   WOCE Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, and I2
2  Sampling depths at all hydrographic stations occupied during the R/V Knorr
   Indian Ocean survey along WOCE Section I9N
3  Example of ODV station mode plot: measurements vs depth for Stations
   172 174 of Section I9N
4  Distribution of the TCO2 and TALK in seawater along WOCE Section I9N
5  Property-property plots for all stations occupied during the R/V Knorr
   cruise along WOCE Section I9N



LIST OF TABLES

Table

 1  Technical characteristics of R/V Knorr
 2  Dates, ports of call, expedition codes (EXPOCODEs), and names of chief
    scientists during Indian Ocean CO2 survey cruises
 3  WOCE measurement programs and responsible institutions during
    Indian Ocean CO2 survey cruises
 4  Principal investigators and senior at-sea personnel responsible for the
    WOCE measurement programs during Indian Ocean CO2 survey cruises
 5  Personnel responsible for carbonate system parameter measurements,
    number of CTD stations, and number of TCO2 and TALK analyses made
    during Indian Ocean CO2 survey cruises
 6  Required WHP accuracy for deep water analyses
 7  The short-term precision of the nutrient analyses for Indian Ocean Section I2
 8  Certified salinity, TALK, and TCO2 for CRM supplied for Indian
    Ocean CO2 survey
 9  Precision of discrete TCO2 analyses during Indian Ocean CO2 survey
10  Mean difference and standard deviation of the differences between at-sea
    TCO2 by coulometry and on-shore TCO2 by manometry on aliquots of the same
    sample from Indian Ocean CO2 survey, and mean replicate precision of the
    manometric analyses
11  Mean analytical difference (TALK) between analyzed and certified TALK
    for CRM used during Indian Ocean CO2 survey
12  Mean analytical difference (TALK) between analyzed and certified TALK
    for each section during Indian Ocean CO2 survey
13  Final count of carbonate system parameter (CSP) analyses during Indian Ocean
    CO2 survey
14  Content, size, and format of data files



ACRONYMS

A/D      analog-to-digital
ADCP     acoustic Doppler current profiler
ALACE    autonomous Lagrangian circulation explorer
BOD      biological oxygen demand
BNL      Brookhaven National Laboratory
14C      radiocarbon
CALFAC   calibration factor
CDIAC    Carbon Dioxide Information Analysis Center
CFC      chlorofluorocarbon
CO2      carbon dioxide
CTD      conductivity, temperature, and depth sensor
CRM      certified reference material
d.f.     degree of freedom
DIW      deionized water
DOE      U.S. Department of Energy
EEZ      Exclusive Economic Zone
emf      electro-magnetic fields
EXPOCODE expedition code
FSI      Falmouth Scientific Instruments
fCO2     fugacity of CO2
FTP      file transfer protocol
GO       General Oceanics
GMT      Greenwich mean time
GPS      global positioning system
Hcl      hydrochloric acid
IAPSO    International Association for the Physical Sciences of the Ocean
IMET     Improved METeorology
I/O      input-output
JGOFS    Joint Global Ocean Flux Study
kn       knots
LADCP    lowered ADCP
LDEO     Lamont-Doherty Earth Observatory
MATS     Miami University alkalinity titration systems
NBIS     Neil Brown Instrument system
NCSU     North Carolina State University
NDP      numeric data package
NOAA     National Oceanic and Atmospheric Administration
nm       nautical mile
NSF      National Science Foundation
ODF      Ocean Data Facility
ONR      Office of Naval Research
OSU      Oregon State University
PC       personal computer
PI       principal investigator
POC      particulate organic carbon
PMEL     Pacific Marine Environmental Laboratory
PU       Princeton University
QA       quality assurance
QC       quality control
R/V      research vessel
RSMAS    Rosenstiel School of Marine and Atmospheric Sciences
SIO      Scripps Institution of Oceanography
SOMMA    single-operator multiparameter metabolic analyzer
SSW      standard seawater
TAMU     Texas A&M University
TALK     total alkalinity
TCO2     total carbon dioxide
TD       to-deliver
UH       University of Hawaii
UM       University of Miami
UW       University of Washington
VFC      voltage to frequency converter
WHOI     Woods Hole Oceanographic Institution
WHPO     WOCE Hydrographic Program Office
WOCE     World Ocean Circulation Experiment
WHP      WOCE Hydrographic Program




                                   ABSTRACT

Johnson K. M.,  A. G. Dickson,  G. Eischeid,  C. Goyet, P. R. Guenther,
        R. M. Key, K. Lee,  E. R. Lewis,  F. J. Millero,  D. Purkerson,
        C. L. Sabine,  R. G. Schottle,  D. W. R. Wallace,  R. J. Wilke,
        and C. D. Winn.  2002.  Carbon Dioxide, Hydrographic and Chemi-
        cal Data Obtained During the Nine R/V Knorr Cruises Comprising
        the Indian Ocean CO2 Survey  (WOCE Sections I8SI9S, I9N, I8NI5E,
        I3, I5WI4, I7N, I1, I10, and I2;  December 1, 1994 - January 22,
        1996),  Ed. A. Kozyr.  ORNL/CDIAC-138, NDP-080.  Carbon Dioxide
        Information Analysis Center, Oak Ridge National Laboratory, U.S.
        Department of Energy, Oak Ridge, Tennessee.

This document describes the procedures and methods used to measure total carbon
dioxide (TCO2) and total alkalinity (TALK) at hydrographic stations taken during
the R/V Knorr Indian Ocean cruises (Sections I8SI9S, I9N, I8NI5E, I3, I5WI4,
I7N, I1, I10, and I2) in 1994 1996.  The measurements were conducted as part of
the World Ocean Circulation Experiment (WOCE).  The expedition began in
Fremantle, Australia, on December 1, 1994, and ended in Mombasa, Kenya, on 
January 22, 1996.  During the nine cruises, 12 WOCE sections were occupied.

Total carbon dioxide was extracted from water samples and measured using single-
operator multiparameter metabolic analyzers (SOMMAs) coupled to coulometers.
The overall precision and accuracy of the analyses was ±1.20 µmol/kg.  The
second carbonate system parameter, TALK, was determined by potentiometric
titration.  The precision of the measurements determined from 962 analyses of
certified reference material was ±4.2 µmol/kg (REFERENCE).  This work was
supported by grants from the National Science Foundation, the U.S. Department
of Energy, and the National Oceanographic and Atmospheric Administration.

The R/V Knorr Indian Ocean data set is available as a numeric data package (NDP)
from the Carbon Dioxide Information Analysis Center (CDIAC).  The NDP consists
of 18 oceanographic data files, two FORTRAN 77 data retrieval routine files, a
readme file, and this printed documentation, which describes the contents and
format of all files as well as the procedures and methods used to obtain the
data.  Instructions for accessing the data are provided.

Keywords: carbon dioxide; TCO2; total alkalinity; coulometry; gas
          chromatography; World Ocean Circulation Experiment; Indian
          Ocean; hydrographic measurements; carbon cycle.



1.  BACKGROUND INFORMATION

The World Ocean Circulation Experiment (WOCE) Hydrographic Program (WHP) was a
major component of the World Climate Research Program.  The primary WOCE goal
was to understand the general circulation of the global ocean well enough to be
able to model its present state and predict its evolution in relation to long-
term changes in the atmosphere.  The impetus for the carbon system measurements
arose from concern over the rising atmospheric concentrations of carbon dioxide
(CO2).  Increasing atmospheric CO2 may intensify the earth's natural greenhouse
effect and alter the global climate.

The carbon measurements, which were carried out on the U.S. WOCE Indian Ocean
cruises, were supported as a core component of the Joint Global Ocean Flux
Study (JGOFS).  This coordinated effort received support in the United States
from the U.S. Department of Energy (DOE), the National Oceanic and Atmospheric
Administration (NOAA) and the National Science Foundation (NSF).  Goals were to
estimate the meridional transport of inorganic carbon in a manner analogous to
the estimates of oceanic heat transport (Bryden and Hall 1980; Brewer, Goyet,
and Drysen 1989; Holfort et al. 1998; Roemmich and Wunsch 1985) and to build a
database suitable for carbon-cycle modeling and the estimation of anthropogenic
CO2 in the oceans.  The global data set includes approximately 23,000 stations.
Wallace (2001) recently reviewed the goals, conduct, and initial findings of
the survey.

This report discusses the CO2 science team effort to sample the entire Indian
Ocean for inorganic carbon (Fig.1).  The total CO2 (TCO2) and total alkalinity
(TALK) were measured in the water column and the fugacity of CO2 (fCO2) in the
surface waters [see Sabine and Key (1998) for a description of the fCO2 methods
and data].  The TCO2 analytical systems were furnished and set up by Brookhaven
National Laboratory under the supervision of D.W.R. Wallace and K.M.
Johnson, and the alkalinity titrators were furnished and set up by the
University of Miami under the supervision of F.J. Millero.  During the survey,
certified reference material (CRM) was used to ensure measurement accuracy.  All
shipboard measurements followed standard operating procedures (DOE 1994).  This
report focuses on TCO2 and TALK measurements.  Because the team shared equipment
throughout all nine cruises and so much material, including quality assessments
of the data, has already appeared in the refereed literature, it will be
limited to a brief summary.  Published documentation appears in appendices.


2.  DESCRIPTION OF THE EXPEDITION

2.1.  R/V Knorr: Technical Details and History

The R/V Knorr, built in 1969 by the Defoe Shipbuilding Company in Bay City,
Michigan, is owned by the U.S. Navy.  It was turned over to the Woods Hole
Oceanographic Institution in 1971 for operation under a charter agreement with
the Office of Naval Research.  It was named for E.R. Knorr, a hydrographic
engineer and cartographer who in 1860 held the title of Senior Civilian and
Chief Engineer Cartographer of the U.S. Navy Office.  Its original length and
beam were 245 and 46 ft, respectively.  Beginning on February 6, 1989, it
underwent a major midlife retrofit or "jumbo-izing" at the McDermott Shipyard
in Amelia, Louisiana.  A midsection was added to the ship to stretch its length
by 34 ft, to 279 ft, and fore and aft azimuthing propulsion systems were added
to make it one of the most maneuverable and stable ships in the oceanographic
fleet. By the time it was returned to the Woods Hole Oceanographic Institution
in late 1991, the retrofit had taken 32 months.  The P6 Section was the vessel's
first scientific cruise after the retrofitting.  The R/V Knorr was designed for
a wide range of oceanographic operations and possesses antiroll tanks and a
strengthened bow for duty in icy waters.  Like its sister ship, the R/V
Melville, it is used for ocean research and routinely carries scientists from
many different countries.  Table 1 provides a list of technical characteristics
of the R/V Knorr, while Table 2 provides individual cruise information,
parameters measured, and responsible personnel with their institutional
affiliations.


2.2.  The Indian Ocean CO2 Survey Cruises Information

      Ship name:            R/V Knorr
      Cruise/Leg:           WOCE Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N,
                            I1, I10, and I2
      Ports of call:        Fremantle Australia (start), and
                            Mombasa, Kenya (end)
      Dates:                December 1, 1994 - January 22, 1996
      TALK instrumentation: F.J. Millero, RSMAS
      TCO2 instrumentation: D.W.R. Wallace and K.M. Johnson, Brookhaven
                            National Laboratory (BNL)
      Reference material:   A.D. Dickson, SIO
      Funding support:      DOE, NSF
      Chief scientist:      See Table 2


TABLE 2: Dates, ports of call, expedition codes (EXPOCODEs), and names of chief
         scientists during Indian Ocean CO2 survey cruises
_________________________________________________________________________________________

 Section  Start     Finish    From        To          EXPOCODE       Chief
          date      date                                             Scientist
 -------  --------  --------  ----------  ----------  ------------   -------------------
 I8SI9S   12/01/94  01/19/95  Fremantle   Fremantle   316N145_5      M. McCartney (WHOI)
 I9N      01/24/95  03/06/95  Fremantle   Colombo     316N145_6      A. Gordon (LDEO)
 I8NI5E   03/10/95  04/16/95  Colombo     Fremantle   316N145_7      L. Talley (SIO)
 I3       04/20/95  06/07/95  Fremantle   Port Louis  316N145_8      W. Nowlin (TAMU)
 I5WI4    06/11/95  07/11/95  Port Louis  Port Louis  316N145_9      J. Toole (WHOI)
 I7N      07/15/95  08/24/95  Port Louis  Muscat      316N145_10     D. Olson (RSMAS)
 I1       08/29/95  10/18/95  Muscat      Singapore   316N145_11,12  J. Morrison (NCSU)
 Dry Dock 10/19/95  11/05/95  Dampier
 I10      11/06/95  11/24/95  Dampier     Singapore   316N145_13     N. Bray (SIO)
 I2       11/28/95  01/22/96  Singapore   Mombasa     316N145_14,15  G. Johnson (PMEL)
_________________________________________________________________________________________

      Participating Institutions:
      LDEO   Lamont-Doherty Earth Observatory
      NCSU   North Carolina State University
      PMEL   Pacific Marine Environmental Laboratory
      RSMAS  Rosenstiel School of Marine and Atmospheric Science
      SIO    Scripps Institution of Oceanography
      WHOI   Woods Hole Oceanographic Institution


The extent and nature of the complete measurement program and the responsible
institutions for each cruise are summarized in Table 3.


TABLE 3: WOCE measurement programs and responsible institutions during
         Indian Ocean CO2 survey cruises
________________________________________________________________________

 Program                        Section/Cruise
              I8SI9S  I9N   I8NI5E  I3    I5WI4  I7N   I1    I10   I2
 -----------  ------  ----  ------  ----  -----  ----  ---   ----  ----
                             Responsible institution(a)
 -----------  ---------------------------------------------------------
 CTD/Rosette  WHOI    ODF   ODF     ODF   ODF    ODF   WHOI  ODF   WHOI
 BTL Oxygen   WHIO    ODF   ODF     ODF   ODF    ODF   WHOI  ODF   WHOI
 BTL Salts    WHOI    ODF   ODF     ODF   ODF    ODF   WHOI  ODF   WHOI
 Nutrients    OSU     ODF   ODF     ODF   ODF    ODF   OSU   ODF   OSU
 CFCs         LDEO    UM    LDEO    SIO   UW     UM    UW    UM    PMEL
 He/Tr        LDEO    WHOI  WHOI    WHOI  WHOI   UM    WHOI  WHOI  WHOI
 Deep He/Tr                         LDEO  LDEO         UM    WHOI  LDEO
 14C          UW      PU    PU      PU    PU     PU    PU    PU    PU
 ADCP         UH      UH    UH      OSU   UH     UH    SIO   SIO   UH
 TCO2, TALK   BNL     PU    UH      RSMAS BNL    UH    SIO   SIO   UH
________________________________________________________________________
(a) Participating institutions: 
    BNL    Brookhaven National Laboratory 
    LDEO   Lamont-Doherty Earth Observatory 
    NCSU   North Carolina State University
    PMEL   Pacific Marine Environmental Laboratory
    ODF    Ocean Data Facility (SIO)
    OSU    Oregon State University
    PU     Princeton University
    RSMAS  Rosenstiel School of Marine and Atmospheric Science (UM)
    SIO    Scripps Institution of Oceanography, Univ. of California, San Diego
    TAMU   Texas A&M University
    UH     University of Hawaii
    UM     University of Miami
    UW     University of Washington
    WHOI   Woods Hole Oceanographic Institute


The principal investigators (PIs) and the senior technical staff for the WOCE
measurements program are summarized in Table 4.


TABLE 4: Principal investigators and senior at-sea personnel responsible for
         WOCE measurement programs during Indian Ocean CO2 survey cruises

__________________________________________________________________________________

 Program        Responsible personnel (Institution)
 -------------  -----------------------------------------------------------------
 CTD/Rosette    James Swift (SIO/ODF), John Toole (WHOI),  Frank Delahoyde
                (SIO/ODF), Carl Mattson (SIO/ODF), Marshall Swartz (WHOI), Laura
                Goepfert (WHOI)
 Bottle oxygen  James Swift (SIO/ODF), John Toole (WHOI), George Knapp (WHOI),
                John Boaz (SIO/ODF)
 Bottle salts   James Swift (SIO/ODF), John Toole (WHOI), George Knapp (WHOI)
 Nutrients      Louis Gordon (OSU), James Swift (SIO/ODF), Marie-Claude Beaupre
                (ODF), Joe Jennings (OSU)
 CFCs           John Bullister (PMEL), Rana Fine (RSMAS), William Smethie (LDEO),
                Mark Warner (UW), Ray Weiss (SIO), Kevin Sullivan (RSMAS),
                Frederick A. Van Woy (SIO)
 He/Tr          William Jenkins (WHOI), Peter Schlosser (LDEO), Zafer Top 
                (RSMAS), Peter Landry (WHOI)
 14C            Robert Key (PU)
 ADCP           Teri Chereskin (SIO), Peter Hacker (UH), Eric Firing (UH), Mike
                Kosro (OSU)
 TCO2, TALK     See Table 5
__________________________________________________________________________________


Table 5 contains a summary of the personnel responsible for the discrete carbon-
ate system measurements.


TABLE 5: Personnel responsible for carbonate system parameter measurements,
         number of CTD stations, and number of TCO2 and TALK analyses made
         during Indian Ocean CO2 survey cruises
         ______________________________________________________________________

          Section  Institution  PI(s)       Group       Stations  TCO2    TALK
                                            Leader        (No.)   (No.)   (No.)
          -------  -----------  ----------  ----------  --------  -----   ----
          I8SI9S   BNL          D. Wallace  K. Johnson    147     2184    1910
                                K. Johnson
          I9N      PU           R. Key      C. Sabine     131     2511    2504
                                C. Sabine
          I8NI5E   UH           C. Winn     C. Winn       166     2419    2421
          I3       RSMAS        F. Millero  D. Purkerson  120     1734    1810
          I5WI4    BNL          D. Wallace  R. Wilke      136     1991    1831
                                K. Johnson
          I7N      UH           C. Winn     R. Schottle   156     2235    2577
          I1       WHOI         C. Goyet    G. Eischeid   158     2400    2387
          I10      PU           R. Key      C. Sabine      61      927     926
                                C. Sabine
          I2       UH           C. Winn     R. Schottle   168     2562    2562
          --------------------------------------------------------------------
          Total                                          1244    18963   18928
         ______________________________________________________________________



2.3.  Brief Cruise Summary

Unlike other CO2 survey cruises where a single institution was responsible for
all phases of the work, these cruises were a group effort in which the
measurement groups used the same ship and instrumentation for a 14-month
period.  BNL supplied two single-operator multiparameter metabolic analyzers
(SOMMA) systems [S/N 004(I) and 006(II)] that were certified at BNL.  A complete
back-up system (S/N 023) was supplied by WHOI.  The alkalinity titrators were
supplied by RSMAS.  Preparation began with a 4-day workshop held in September
1994 at RSMAS under the direction of and in the laboratory of F.J. Millero.
Cruise participants and group leaders from BNL, LDEO, SIO, RSMAS, PU, WHOI, and
UH were instructed in the use of the alkalinity titrators by F.J. Millero and
D. Campbell and in the use of the SOMMA-coulometer systems by K.M. Johnson and
R.W. Wilke.  The day after Thanksgiving the BNL and RSMAS TCO2 groups left for
Australia.  Setup of the alkalinity and coulometric titration systems began on
November 28, 1994.  The I8SI9S cruise began on December 1, 1994.

The first of the nine cruises on the R/V Knorr was the longest continuous cruise
during the survey.  It occupied a series of CTD stations along two north-south
tracks essentially proceeding from Australia to the ice edge (I8S) along 90°E
and then back again to Australia (I9S) at approximately 110°E.  Station 
spacing ranged from 5 to 40 nautical miles (nm).  Testing and selection of the 
best of the available titration systems and components was completed during I8S.  
The alkalinity and especially the coulometric titration systems benefited from 
This "shake-out" period.  Components damaged during transit were identified and
repaired or replaced.  By the beginning of the I9S, operations were more or less
routine.  Except for one approximately 12-h period when high winds of ~60 knots
(kn) made sampling impossible, work proceeded pretty much on schedule during the
50-day cruise.  During the cruise the ability of a team of four marine mammal
and bird observers onboard from PMEL, under the direction of C. Tynan, to remain
in the cold weather and identify whales that were little more than blips on the
horizon amazed all participants of the expedition.  Both Christmas and New Year
holidays were celebrated aboard the ship.  The fine Christmas dinner was
highlighted by the appearance of three humpback whales, who put on a spectacular
display, jumping and passing under and about the ship.  The ship docked in
Fremantle, to the relief of the CO2 team members, on January 19, 1995, after 147
stations were occupied.  Measurement crews were exchanged, and the new team
brought along some badly needed spare parts and components.

The ship departed Fremantle for I9N on January 24 with A. Gordon as Chief
Scientist and a CO2 measurement group from PU.  This section was basically a
northward continuation of I8S.  The weather was perfect during all 43 days of
the cruise.  The participants celebrated the equator crossing on February 14.
This cruise ended on March 5 in Colombo, Sri Lanka, with 131 stations logged.
During the stopover, the carrier gas supply for the coulometric titrators was
shifted from bottled high purity nitrogen to a calibration gas generator (Peak
Scientific), which supplied CO2-free carrier gas for the remaining of the
cruises.

I8NI5E began in Colombo on March 10 with L. Talley as chief scientist and a CO2
measurement group from UH on board.  No problems were noted for the sampling
program, and the weather remained excellent for most of this leg.  The ship
track proceeded southward from Sri Lanka along 88°E to 24°S, then angled
southeastward to the junction of the Ninety-East Ridge and Broken Ridge.  Next,
the ship followed a 1987 section along approximately 32°S.  This zonal section
included the Central Indian Basin, and crossed the northward flow of deep water
just west of Australia.  Due to the good weather, some extra sampling was
carried out, and by the time the ship docked in Fremantle on April 15, 166
stations had been occupied.  On station 296, the rosette accidentally hit bottom
at 3630 m, but the cast was successfully completed.  A postcruise inspection
showed no apparent damage to the equipment.  This cruise included sampling for
particulate organic carbon (POC) in the surface waters near the equator.  POC
samples were also taken at 65 stations for 13C/12C analyses.  Between April 15
and 23, measurement crews were exchanged and spare parts inventories were
updated.

On April 23, the R/V Knorr departed Fremantle for section I3 with W. Nowlin as
chief scientist and a CO2 measurement group from RSMAS.  The ship had to detour
almost immediately back to Fremantle for a medical emergency.  The injured
analyst was able to rejoin the ship in Port Louis, Mauritius.  In addition to
the CTD work, this cruise included the deployment of current meters, drifters,
and autonomous Lagrangian circulation explorer (ALACE) floats.  The cruise track
ran along 20°S from Australia to Mauritius to Madagascar, crossing the West
Australian Basin, Ninety-East Ridge, Central Indian Basin, and Central Indian
Ridge before veering southward to 22  S around Rodrigues Island.  After this, it
proceeded to the east coast of Mauritius, where a 2-day port stop was made in
Port Louis.  Returning to sea, the ship continued sampling westward along 20°S
from the continental shelf to Madagascar.  Weather was characterized by
southeasterly winds of 10-20 kn, mostly sunny skies, occasional rain squalls,
and 4-6 ft swells with slightly higher winds and seas in mid-May.  The Knorr
returned to Port Louis, Mauritius, on June 5 with 120 stations logged.

The next cruise, I4I5W, began on June 11 with J. Toole as chief scientist and a
CO2 measurement group from BNL on board.  This leg focused on major circulation
features of the southwest region of the Indian Ocean, including the region where
the Agulhas Current originates and where dense waters filtering through 
fractures in the Southwest Indian Ridge form a northward deep boundary current
east of Madagascar.  The cruise track formed a closed box to aid in deducing the
absolute circulation.  A stop was made in Durban, South Africa, on June 21 to
pick up a replacement drum of CTD wires.  Attempts were also made to repair the
ship's bow thruster, which had failed very early in the leg; although the repair
was not successful, the lack of a bow thruster had no effect on the scientific
work.  The R/V Knorr departed Durban on June 22 and began I5W including 
reoccupation of stations where data had been taken in 1987.  Bad weather was
experienced on June 30 when wind gusts of 40-50 kn and high seas slowed winch
operations.  As the ship moved across the Madagascar Basin toward port, station
spacing was decreased to 20 nm.  When the ship arrived in port on July 11, 136
stations had been occupied 20 more than planned.

After four days in port, the R/V Knorr departed on I7N with D. Olson as chief
scientist and a CO2 measurement group from UH.  The director of the U.S. WOCE
office, Piers Chapman, was aboard and served as a salt analyst during the
section.  I7N was designed to define the water mass properties and transports
across the Mascarene Basin and to measure water mass properties and baroclinic
structure on a short section across the Amirante Passage, located between the
Mascarene and Somali Basins.  It included a cross-equatorial section and a
reoccupation of stations previously sampled to confirm water mass flows.  This
work included sampling along 65°E in the central Arabian Basin.  The 
concluding phase of the cruise was a deep line of stations up the center of the 
Gulf of Oman.  The last station of this phase was in the Strait of Hormuz, and 
it identified inflows of Arabian (Persian) Gulf water into the Arabian Basin.  
The cruise terminated on August 24 in Muscat, Oman, with 156 stations occupied.

After a 5-day layover, the R/V Knorr departed Muscat on I1 with J. Morrison as
chief scientist and a CO2 measurement group from WHOI.  I1 was the northernmost
Indian Ocean section.  It enclosed the Arabian Sea and Bay of Bengal, which are
important sources of salt and fresh water, respectively.  The Knorr proceeded
from Muscat to the southern end of the Red Sea and then to the coast of Somali,
where the zonal section started at a nominal latitude of 8°N.  The section
crossed the Arabian Sea, in part to study the carbon transport in and out of the
Arabian Sea, and ended on the continental shelf of India.  After a brief port
stop in Colombo, Sri Lanka, on September 28-30, the leg continued from the Sri
Lankan shelf across the Bay of Bengal to the Myanmar continental shelf.  CTD
problems caused considerable difficulty for the scientific party and resulted in
a somewhat noisy hydrographic data set compared to data obtained from the other
sections.  After the last station on the Myanmar shelf, the Knorr deadheaded to
Singapore, arriving on October 16 with 158 stations logged.  I1 was not only the
northernmost section, it was clearly the most adventurous.  ALACE float 
deployments had to be canceled in the territorial waters of India because the
Indian observer on board refused to allow them, and then the threat of pirates
caused the cancellation of a planned section across the Gulf of Aden.  In the
vicinity of Colombo, the ship had to be escorted by four Sri Lankan gunboats,
and planned stops at stations over the Trincomalee Canyon could not be taken
because of the threat of attack by the Tamil Tigers.  Nevertheless, the Knorr
was able to coordinate scientific activities and physical oceanographic
measurements with the nearby R/V Meteor (F. Schott, chief scientist) in an area
of German current meter moorings near Socotra.  Sampling during I1 enabled
comparison of bottle and TCO2 data with earlier JGOFS results and Meteor Pegasus
and Knorr lowered acoustic Doppler current profiler (LADCP) horizontal 
velocities.  From Singapore, the Knorr proceeded to Dampier, Australia, where it
was placed in dry dock from October 19 until November 5.

With the R/V Knorr back in the water, the I10 CO2 measurement group from PU
arrived.  This group was required to do some additional work not normally part 
of the crew exchange routine.  During the dry dock period, the CO2 
instrumentation had been depowered, and the measurement group had to repower and 
check the instrumentation.  Some minor repairs were required for the coulometric
titrators, including the replacement of one or two solenoid valves (the only
valves replaced during the cruises).  In addition, the sample pipettes and
coolant lines were dismounted and cleaned of algal growth.

The R/V Knorr departed Dampier, Australia, on November 11 with N. Bray as chief
scientist.  WOCE Section I10 was set to run from Shark Bay, Western Australia,
to the Indonesian Exclusive Economic Zone (EEZ) 120 nm south of Sunda Strait.
However, constraints imposed by the Indonesian government caused the endpoint to
be moved from the Sunda Strait to near central Java.  The Knorr was not granted
permission to enter the EEZ of Indonesia, and concluding stations had to be
taken along the boundary of the EEZ.  These restrictions prevented full
resolution of the South Java current.  Throughout the Indian Ocean survey,
bottle casts were normally made to within 5-20 m of the bottom; however, on I10
four stations over the Java Trench this could not be done.  Instead, the casts
were made to the maximum CTD depth of 6000 m.  The quality of the bottle data
was considered to be excellent throughout with very few mis-trips.  ALACE floats
were also released during this cruise.  A festive Thanksgiving was celebrated
aboard the ship, and after the last station (1075), the Knorr steamed to
Singapore, arriving on November 28, with 61 stations logged.

The R/V Knorr departed Singapore on December 2 for the last Indian Ocean WOCE
section, I2, with G. Johnson as chief scientist and the UH CO2 measurement group
aboard.  Again, clearance for work in the Indonesian EEZ was not available, and
after a 3-day steam, work commenced with a reoccupation of the final station of
the I10 Section (station 1075).  The Knorr skirted the Indonesian EEZ and moved
westward, crossing the Ninety-East Ridge and the Chagos-Laccadive Ridge.  The
ship continued at approximately 8°S until it made a brief port call in Diego
Garcia from December 28-30.  At this point, the chief scientist departed the
ship and was replaced by Bruce Warren, accompanied by two Kenyan observers.  The
Knorr returned to the 8°S line, passing the crest of the Central Indian Ridge
and then the Mascarene Plateau before it turned southwestward and crossed the
Amirante Passage on the way to the northern tip of Madagascar.  Rounding the
tip, the ship headed northwest toward Africa, making a dogleg to avoid the
Tanzanian EEZ.  After completing the final Indian Ocean Survey station 1244, it
proceeded to Mombasa, arriving on January 22, 1996, with 168 stations logged.

For inorganic carbon, the principal analytical problems for the cruise centered
on the breakage of glass components in the alkalinity titrators; resupply;
accumulation of bubbles in the acid lines of the alkalinity titrators; damaged
coulometric cathode electrodes; algal growth in the sample lines, baths,
pipettes, and alkalinity cells; wide swings in laboratory temperature (19-33 C),
and the failure of the TCO2 glassware drying oven.  Fortunately, glassware
drying oven was repaired.  Temperature swings (21-29 C) were also noted for the
salinometer and nutrient laboratories.  The most vexing problem for the
inorganic carbon analysts was the failure of the refrigerated baths used by both
the alkalinity and coulometric titration systems.  The baths had to be
constantly jury-rigged so that one bath did the work of two, repaired by ship's
technicians when possible, or replaced when possible.  The two groups used
almost 12 different baths, and by the time the work ended, not one could be
considered in reliable condition.  Some were never repaired, while others were
repaired and used for the North Atlantic survey in 1997.


3.  DESCRIPTION OF VARIABLES AND METHODS

3.1.  Hydrographic Measurements

During the survey, responsibility for hydrographic and bottle data was divided
between ODF and WHOI.  Each of these groups uses or may use different
procedures.  Hence, the hydrographic measurements are described in separate
sections.  Because the greater number of the cruises were made under the
auspices of SIO/ODF, the bulk of the methods description is provided in Sect.
3.1.1.  Information specific to WHOI is given in Sect. 3.1.2; in this section
however, the discussion is limited to significant differences between the
SIO/ODF and WHOI operations or methods.  Unless otherwise stated in Sect. 3.1.2,
material presented in Sect. 3.1.1 applies to all cruises.  Sect. 3.1.3 contains
a brief description of the underway measurements common to all cruises.


3.1.1  SIO/ODF Methods and Instrumentation

Hydrographic measurements consisted of salinity, dissolved oxygen, and nutrient
(nitrite, nitrate, phosphate, and silicate) samples collected from Niskin
bottles filled during CTD/rosette casts, and temperature, pressure, salinity,
and dissolved oxygen from the CTD.  At 5- to 40-nm intervals, depending on the
topography, hydrographic casts were made to within 5 20 m of the bottom with a
36-bottle Rosette frame belonging to ODF.  This unit consisted of a 36-bottle
frame, thirty six 10-L bottles, and a 1016 General Oceanics (GO) 36-place pylon.
The GO pylon was used in conjunction with an ODF-built deck unit and power
supply.  The underwater components comprising the CTD included an ODF-modified
Neil Brown Instrument Systems (NBIS) Mark III CTD with conductivity, pressure,
oxygen, and temperature sensors.  The underwater package also consisted of a
SeaTech transmissometer, an LADCP, a Sensormedics dissolved oxygen sensor, a
Falmouth Scientific Instruments (FSI) secondary PRT sensor, a Benthos altimeter,
and a Benthos pinger.  The CTD was mounted horizontally along the bottom of the
frame, while the LADCP was vertically mounted inside the bottle rings.  The
system was suspended from and powered by a three- conductor 0.322-in.
electromechanical cable.  The Rosette was deployed from the starboard side using
either the port side Markey CTD or the starboard side Almon Johnson winch.
Standard CTD practices (i.e., soaking the conductivity and O2 sensors in
distilled water between casts and protecting the sensors against sunlight and
wind by storing the rosette in the hanger between casts) were observed
throughout the cruises.  Regular CTD maintenance included the replacement of O-
rings when needed, bottle inspections, and a regular cleaning of the
transmissometer windows.  At the beginning of each station the time, position,
and bottom depth were logged.  The CTD sensors were powered and control was
transferred to the CTD acquisition and control system in the ship's laboratory.
The CTD was lowered to within 10 m of the bottom if bottom returns were
adequate.  Continuous profiles of horizontal velocity from the sea surface to
the bottom were made for most CTD/rosette casts using the LADCP.

The CTD's control and acquisition system displayed real-time data [pressure,
depth, tem- perature, salinity (conductivity), oxygen, and density] on the video
display of a SunSPARC LX computer.  A video recorder was provided for real-time
analog backup.  The Sun computer system included a color display, a keyboard, a
trackball, a 2.5-GB disk, 18 RS-232 ports, and an 8-mm cartridge tape.  Two
additional Sun systems were networked for display, backup, and processing.  Two
HP 1200 C color ink-jet printers provided hard copy.  The ODF data acquisition
software not only acquired the CTD data but also processed it so that the real-
time data included preliminary sensor corrections and calibration models for
pressure, temperature, and conductivity.  The sampling depths were selected
using down-cast data.  Bottles were tripped on the up-cast.  Bottles on the
rosette were identified with a serial number and the pylon tripping sequence, 1-
36, where the first (deepest) bottle tripped was no. 1.  For shallow-depth
stations, fewer than 36 bottles were closed.

After the CTD was on deck, the acquisition system, the CTD, the pylon, and video
recording were turned off and the sensor protective measures were completed
before sampling began.  If a full suite of samples was drawn, the sampling order
was CFCs, 3He, O2, TCO2, TALK, 14C, 3H, nutrients, and salinity.  Only salinity,
O2, and nutrients were measured at every station.  A deck log was kept to
document the sampling sequence and to note anomalies (e.g., status of bottle
valves, leaks, etc.).  One member of the sampling crew was designated the
"sample cop," and it was his or her responsibility to maintain this log and to
ensure that the sampling order was followed.  Oxygen sampling included
measurement of the temperature, which proved useful for determining leaking or
mis-tripped bottles.  Following the cruises, WHP quality flags were assigned
according to the WOCE Operations Manual (Joyce and Corry 1994) to each measured
quantity.

The principal ODF CTD (no. 1) was calibrated for pressure and temperature at the
ODF Calibration Facility (La Jolla, Calif.) in December 1994 prior to the five
consecutive WOCE Indian Ocean sections beginning with I9N and ending with I7N.
The CTD was also calibrated postcruise in September 1995 prior to the I10
cruise.  Pre- and postcruise laboratory calibrations were used to generate
tables of corrections, which were applied by the CTD data.  At sea, bottle
salinity and oxygen data were to calibrate or check the CTD sensors.  Additional
details concerning calibration and the CTD data processing can be obtained from
the chief scientists' cruise reports at the WHPO web site: http://whpo.uscd.edu/.

Bottle salinity samples were collected in 200-mL Kimax high alumina borosilicate
bottles, sealed with custom-made plastic insert thimbles and Nalgene screw caps.
Salinity was determined after equilibration in a temperature-controlled 
laboratory, usually within 8-20 h of collection.  Salinity was measured with two
ODF-modified Guildline Autosal Model 8400A salinometers, normally at 21 or 
24°C, depending on the prevailing temperature of the salinometer laboratory.  
The salinometers included interfaces for computer-aided measurements (e.g.,
acquiring the measurements, checking for consistency, logging results, and
prompting the analyst).  The salinometers were standardized with International
Association for the Physical Sciences of the Ocean (IAPSO) Standard Seawater
(SSW) Batches P-124, P-126, or P-128 using at least one fresh vial per cast
(usually 36 samples).  The accuracy of the determination was normally 0.002
relative to the SSW batch used.  PSS-78 was then calculated for each sample
(UNESCO 1981).  On some stations (e.g., on Section I5EI8N), bottle salinity
exhibited small offsets (0.002 0.004) compared to the corresponding CTD results
and bottle salinity from nearby stations, and corrections of this magnitude need
to be applied to the bottle salinity.  Errors of this magnitude have no
practical effect on the calculated TCO2 or TALK values.  Hence, bottle salinity
is sufficiently accurate to express inorganic carbon results in µmol/kg.

Bottle oxygen was determined by rinsing 125-mL iodine flasks twice and then
filling to overflowing (3x-bottle volume) with a draw tube.  Sample temperature
was measured immediately with a thermometer imbedded in the draw tube.  The
Winkler reagents were added; and the flask was stoppered, shaken, and then
shaken again 20 min later to ensure that the dissolved O2 was completely fixed.
Oxygen was determined within 4 h of collection using a whole-bottle modified
Winkler titration following the technique of Carpenter (1965) and incorporating
the modifications of Culberson et al. (1991) on an SIO/ODF-designed automated
oxygen titrator.  A Dosimat 665 burette driver fitted with a 1.0-mL burette was
used to dispense thiosulfate solution (50 g/L).  Standards prepared from
preweighed potassium iodate (0.012N) were run each time the automated titrator
was used, and reagent blanks were determined by analyzing distilled water.  The
final oxygen results were converted to µmol/kg using the in situ temperature.
Bottle volumes were precalibrated at SIO.  Laboratory temperature stability
during the sections was considered poor, varying from 22 to 28°C over short 
time periods; and therefore, portable fans were used by ODF analysts to maintain
temperature.

Phosphate, nitrate, nitrite, and silicate samples were collected in 45-mL high-
density polypropylene, narrow-mouth, screw-capped centrifuge tubes which were
cleaned with 10% hydrochloric acid (HCl) and then rinsed three times with sample
before filling.  The samples were analyzed on an ODF-modified four-channel
Technicon AutoAnalyzer II, usually within 1 h of the cast, in a temperature-
controlled laboratory.  If the samples were stored for longer than 1 h prior to
analysis, they were stored at 2 6°C (for no more than 4 h).  The AutoAnalyzer
incorporates the method of Armstrong, Stearns, and Strickland (1967) for
silicate, this same method as modified for nitrate and nitrite, and the method
of Bernhardt and Wilhelms (1967) for phosphate.  The last method is described by
Gordon and coworkers (Atlas et al. 1971; Hager et al. 1972; and Gordon et al.
1992).  Standards were analyzed at the beginning and end of each group of sample
analyses, with a set of secondary intermediate concentrations prepared by
diluting preweighed primary standards.  Replicates were also drawn at each
station for measurement of short-term precision.  For reagent blanks, deionized
water (DIW) from a Barnstead Nanopure deionizer fed from the ship's potable
water supply was analyzed.  An aliquot of deep seawater was run with each set of 
samples as a substandard.  The primary standard for silicate was Na2SiF6; and
for nitrate, nitrite, and phosphate the standards were KNO3, NaNO2, and KH2PO4,
respectively.  Chemical purity ranged from 99.97% (NaNO2) to 99.999% (KNO3).

Most hydrographic data sets met or exceeded the WHP requirements.  Some
exceptions for silicate were noted when differences between overlapping stations
on I3 (Station 548) and I4I5W (Stations 705 and 574) approached 3%; these
silicate data (Stations 702-707) were corrected by adding 3% to the original
results.  Instrument problems also caused difficulties for the nitrite and
silicate analyses on many of the I2 cruise stations.  Silicate problems were
noted at some 30% of these stations, with errors typically being on the order of
2 4%.  This required considerable post- cruise evaluation and workup before the
desired between-station precision for deep water values of 1% was attained.
However, users of the I2 silicate data are urged to use caution or to contact
the analysts for assistance.  Because of the difficulties with the nutrient
analyses on the I2 cruise, the post-cruise I2 precision is given in Table 7 as a
"worst case" for comparison with the WHP standards shown in Table 6.  Short-term
precision is the absolute mean difference between replicates analyzed within a
sample run; the standard deviation of the differences is also shown. The authors
know of no remaining CTD problems, that would affect the quality of the 
carbonate system data.


TABLE 6: Required WHP accuracy for deep water analyses
         ___________________________________________

          Parameter  Required accuracy
          ---------  ------------------------------
          Salinity   0.002 relative to SSW analysed
          Oxygen     1% (2 µmol/kg)
          Nitrate    1% (0.3 0.4 µmol/L)
          Phosphate  1% (0.02 0.03 µmol/L)
          Silicate   1% (1 5 µmol/L)
         ___________________________________________


TABLE 7: The short-term precision of the nutrient analyses for Indian Ocean
         Section I2
         ______________________________________

          Parameter     Difference  ± St. Dev.
                         (µmol/L)
          ------------  ----------  ----------
          Nitrate         0.123       0.093
          Phosphate       0.015       0.009
          Silicic Acid    0.440       0.260
         ______________________________________


3.1.2  WHOI Methods and Instrumentations

Unless otherwise stated procedures are as described in Sect. 3.1.1, above.  For
the hydrographic work on I8SI9S, I1, and I2, the R/V Knorr was outfitted with
equipment belonging to both WHOI and SIO/ODF.  For the I8SI9S section a NBIS CTD
was used.  For I1, four CTDs were available.  The primary sensors were two new
FSI CTDs belonging to WHOI with a Sensormedics oxygen sensors, a titanium
pressure transducer, and a temperature monitor.  The secondary sensors were two
NBIS Mark-III CTDs (WHOI Nos. 9 and 12) also with a Sensormedics oxygen sensor,
a titanium pressure transducer, and a temperature monitor. The MKIII CTDs
experienced failures early during I1 (Stations 858 and 864), and the bulk of the
hydrography was carried out using the FSI (Nos. 1338 and 1344) CTDs.  Usually,
the frame was set up with the two CTDs - one configured to send data up the wire
and one configured to record data internally.  Electrical modifications had to
be made to the CTDs and the deck controllers before CTD data dropouts were
eliminated and the confirmation of bottle closure from the pylon was restored.

For the CTDs, a FSI DT-1050 deck unit was initially used to demodulate the data,
but this unit was replaced for most of the cruise with an EG&G MK-III deck unit.
These units fed serial data to two personal computers (PCs) running EG&G CTD
acquisition software, with one displaying graphical output and the other a
running data listing.  After each station, the CTD data were forwarded to
another set of PCs running EG&G postprocessing and software modified by WHOI
(Millard and Yang 1993) in which the data were centered into 2 dbar bins for
data quality control, which included fitting to bottle salinity and oxygen
results.

The CTDs were calibrated before and after the cruise for temperature and
pressure at WHOI by M. Swartz and M. Plueddemann.  Both calibrations were
consistent, but the data set for I1 was considered to be only of fair quality
because noise levels in the data set are somewhat larger than typical for other
CTDs.  For example, this data set has a salt noise level of 0.002 which is 2
times larger than the norm.  Residuals between the bottle and profile data range
from 0.001 to 0.004.  For a detailed discussion of the CTD calibration and
problems experienced at sea during I1, consult the chief scientist's cruise
report on the WHPO web site.

For I2, WHOI CTD No. 9, a WHOI-modified NBIS MK-IIIb, was used.  The CTD
incorporated a Sensormedics oxygen sensor, titanium pressure transducer, and
temperature sensor, which were calibrated in November 1995 immediately before
the cruise.  On most stations, one of the FSI CTDs was used in the memory mode
and downloaded after station sampling to provide independent or backup CTD
traces.  An FSI Ocean Temperature Module was also attached to the MK-III and
CTDs.  The Mark-III CTD data were acquired using an NBIS Mark-III deck
unit/display that provided demodulated data to two PCs, as described for the
Section I1 cruise.  A PC was also devoted to recovering the data from the FSI
CTDs.  Post-cruise calibration, including dunk tests of the CTDs, was completed
in April and May of 1996 in the WHOI calibration laboratory.  The procedure of
Millard and Yang (1993) was used to correct the pressure temperature sensor
calibration post-cruise to eliminate down/up pressure historesis.  Multiple
regression fits of the CTD data to the bottle data were used to calibrate the
oxygen and conductivity sensors.  See the chief scientist's report on the WHPO
web site for further details.

Bottle salinity samples were collected in 200-mL glass bottles with removable
polyethylene inserts and caps.  Then they were removed to a temperature-
controlled van at 23 C and analyzed on a Guildline Autosal Model 8400B
salinometer (WHOI No. 11).  The salinometer was standardized once a day using
IAPSO SSW (128, dated July 18, 1995).  The accuracy was ~0.002.  A complete
description of the WHOI measurement techniques is given by Knapp, Stalcup, and
Stanley (1990).

Bottle oxygen was determined according to procedures given by Knapp, Stalcup,
and Stanley (1990).  WHOI used a modified Winkler technique similar to that
described by Strickland and Parsons (1972).  The oxygen reagents and bi-iodate
standard were prepared at WHOI in August 1994.  There was no evidence that the
reagents or standard deteriorated during the 17 months they were aboard the
Knorr.  Standardization of the thiosulphate titrant was made daily.  The
accuracy of the method was 0.5%, or approximately 1.0 µmol/kg.

The nutrients were analyzed as described in Sect. 3.1.1 (see also Gordon et al.
1994).


3.1.3.  Underway Measurements

Navigational data (heading, speed, time, date, and position) were acquired from
the ship's Magnavox MX global positioning system (GPS) receiver via RS-232 and
logged automatically at 1-min intervals on a SunSPARC station.  Underway
bathymetry was logged manually at 5-min intervals from the hull-mounted 12-kHz
echo sounder and a Raytheon recorder corrected according to methods described by
Carter (1980).  These data were merged with the navigation data to provide a
time-series of underway position, course, speed, and bathymetry data that were
used for all station positions, depths, and vertical sections.  The Improved
METeorology (IMET) sensors logged meteorological data which included air
temperature, barometric pressure, relative humidity, sea surface temperature,
and wind speed and direction at 1-min intervals.  Underway shipboard
measurements were made throughout the work to document the horizontal velocity
structure along the cruise tracks using a 150-kHz hull-mounted acoustic Doppler
current profiler (ADCP) manufactured by RD Instruments.  The ADCP was mounted at
a depth of 5 m below the sea surface.  Underway chemical measurements in
water and air included salinity, pCO2 (PU and SIO), pN2O (SIO), and CH4 (SIO).
Two different systems were used for pCO2; the PU group used a rotating disk
equilibrator and infrared detector, while the Scripps group used a shower type
equilibrator and gas chromatograph for the detection of CO2.  The pCO2
measurements, including a comparison of the shower and disk equilibrator
results, were described by Sabine and Key (1998).

A thermosalinograph (manufactured at FSI) was mounted on the bow approximately
3 m below the surface for underway salinity, which was calibrated against
surface CTD and bottle salinity values after the cruise (Sabine and Key 1998).
The CFC groups periodically analyzed air for CFCs using sampling lines from the
bow and stern of the ship.


3.2.  Total Carbon Dioxide Measurements

TCO2 was determined on 18,963 samples using two automated single-operator
multiparameter metabolic analyzers (SOMMA) with coulometric detection of the CO2
extracted from acidified samples.  A description of the SOMMA-coulometry system
and its calibration can be found in Johnson et al. 1987; Johnson and Wallace
1992; and Johnson et al. 1993.  A schematic diagram of the SOMMA analytical
sequence and a complete description of the sampling and analytical methods used
for discrete TCO2 on the Indian Ocean WOCE sections appear in Appendix B
(Johnson et al. 1998).  Further details concerning the coulometric titration can
be found in Huffman (1977) and Johnson, King, and Sieburth (1985).  The
measurements for the Indian Ocean Survey were made on two systems provided by
BNL (S/Ns 004 and 006) and a backup by WHOI (S/N 023).

TCO2 samples were collected from approximately every other station [~ 60 nm
intervals, 50% of the stations (Fig. 2)] in 300-mL glass biological oxygen
demand (BOD) bottles.  They were immediately poisoned with 200 µL of a 50%
saturated solution of HgCl2, thermally equilibrated at 20°C for at least 1 h,
and analyzed within 24 h of collection (DOE Handbook of Methods 1994).  Certified 
reference material (CRM) samples were routinely analyzed, usually at 
the beginning and end of the coulometer cell lifetime, according to DOE (1994).  
As an additional check of internal consistency, duplicate samples were usually
collected on each cast at the surface and from the bottom waters.  These
duplicates were analyzed on the same system within the run of cast samples from
which they originated, but the analyses were separated in time usually by ~3 h.
Periodically, replicate samples were also drawn for shipboard analysis at sea
using coulometry and for later analysis on shore at SIO by manometry.  The
latter samples, typically designated as the "Keeling samples," consisted of two
500-mL replicate samples collected at two depths (four samples total per
station).  These were analyzed only if both replicates survived the storage and
the return journey to SIO.

Seawater introduced from an automated "to-deliver" (TD) pipette into a stripping
chamber was acidified, and the resultant CO2 from continuous gas extraction was
dried and coulometrically titrated on a model 5011 UIC coulometer.  The 
coulometer was adjusted to give a maximum titration current of 50 mA, and it was
run in the counts mode [the number of pulses or counts generated by the
coulometer's voltage-to-frequency converter (VFC)] during the time the titration
was displayed and acquired by the computer.  In the coulometer cell, the acid
(hydroxyethylcarbamic acid) formed from the reaction of CO2 and ethanolamine was
titrated coulometrically (electrolytic generation of OH-) with photometric
endpoint detection.  The product of the time and the current passed through the
cell during the titration was related by Faraday's constant to the number of
moles of OH- generated and thus to the moles of CO2 that reacted with
ethanolamine to form the acid.  The age of each titration cell was logged from
its birth (time that electrical current was applied to the cell) until its death
(time when the current was turned off).  The age was measured from birth
(chronological age) and in mass of carbon (mgC) titrated since birth (carbon
age).  The systems were controlled with PCs equipped with RS232 serial ports for
the coulometer and the barometer, a 24-line digital input/output (I/O) card for
the solid state relays and valves, and an analog-to-digital (A/D) card for the
temperature, conductivity, and pressure sensors.  These sensors monitored the
temperature of the sample pipette, gas sample loops, and, in some cases, the
coulometer cell.  The controlling software was written in GWBASIC Version 3.20
(Microsoft Corp., Redmond, Wash.), and the instruments were driven from an
options menu appearing on the PC monitor.

The TD volume (Vcal) of the sample pipettes was determined gravimetrically prior
to the cruise and periodically during the cruise by collecting aliquots of
deionized water dispensed from the pipette into pre-weighed serum bottles which
were sealed and re-weighed on shore. The apparent weight of water collected
(Wair), corrected to the mass in vacuo (Mvac), was divided by the density of the
calibration fluid at the calibration temperature to give Vcal.  The sample
volume (Vt) at the pipette temperature was calculated from the expression

                     V(t) = V(cal) [1 + a(v) (t - t(cal))] ,

where av is the coefficient of volumetric expansion for Pyrex-type glass
(1 X 10(^-5)/°C), and t is the temperature of the pipette at the time of a
measurement.  Vcal for the Indian Ocean CO2 survey cruises and a chronology of
the pipette volume determinations appear in Appendix B.

The coulometers were electronically calibrated at BNL prior to the cruises and
recalibrated periodically during the cruises (Sections I8SI9S and I5WI4) to
check the factory calibration as described in Johnson et al. (1993) and DOE
(1994).  The results for the electronic intercepts (Intec) and slopes (Slopeec)
are given in Appendix B.  For all titrations, the micromoles of carbon titrated
(M) was

      M = [Counts/4824.45 - (Blank x T(t)) - (Int(ec) x T(i))]/Slope(ec) ,

where 4824.45 (counts/µmol) was the scaling factor obtained from the factory
calibration, T(t) was the length of the titration in minutes, Blank is the
system blank in µmol/min, and T(i) the time of continuous current flow in
minutes.

The SOMMA-coulometry systems were calibrated daily with pure CO2 (calibration
gas) by titrating the mass of CO2 contained in two stainless steel gas sample
loops of known volume and by analyzing CRM samples supplied by Dr. Andrew
Dickson of the SIO.  The ratio of the calculated (known) mass of CO2 contained
in the gas sample loops to the mass determined coulometrically was the CALFAC
(~1.004).  A complete history of the calibration results appears in Appendix B.
For water and CRM samples, TCO2 concentration in µmol/kg was

                  TCO2 = M x CALFAC x [1 / (V(t) x ñ)] x d(Hg) ,

where p is the density of seawater in g/mL at the analytical t and S calculated
from the equation of state given by Millero and Poisson (1981), and d(Hg) is the
correction for sample dilution with bichloride solution (for the cruises d(Hg) =
1.000666).

System 006 was equipped with a conductance cell (Model SBE-4, Sea-Bird
Electronics, Bellevue, Wash.) for the determination of salinity as described by
Johnson et al. (1993).  Whenever possible, SOMMA and CTD salinities were
compared to identify mis-trips or other anomalies, but the bottle salinities
(furnished by the chief scientist) have been used to calculate p throughout.

Three CRM batches were used for the Indian Ocean Survey.  The certified TCO2
concentrations were determined by vacuum-extraction/manometry in the laboratory
of C.D. Keeling at SIO and are given in Table 8.


TABLE 8: Certified salinity, TALK, and TCO2 for CRM supplied for Indian Ocean
         CO2 survey
               _________________________________________________

                Batch  Salinity  TCO2 (µmol/kg)  TALK (µmol/kg)
                -----  --------  --------------  --------------
                 23     33.483      1993.10         2212.70
                 26     33.258      1978.34         2176.60
                 27     33.209      1988.10         2214.90
               _________________________________________________


Optimal cell and platinum electrode configurations, according to criteria given
in Appendix B, were selected on the first section (I8S) and were used on all
subsequent cruises.

The quality control-quality assurance (QC-QA) of the coulometric TCO2 determina-
tions was assessed from analyses of 983 CRM samples during the nine Indian Ocean
CO2 survey cruises.  For both coulometric titration systems (004 and 006) the
average TCO2 (measurement minus CRM value) for the whole survey was 0.86 µmol/kg
and the standard deviation was ±1.21 µmol/kg.  A cruise-by-cruise breakdown of
the accuracy and precision of the CRM analyses is given in Appendix B.

The small mean difference between the analyzed and certified TCO2 and the very
high precision (1.21 µmol/kg) of the differences indicates that the two systems
gave very accurate and virtually identical results over the entire survey (see
also Fig. 6 in Appendix B).

The second phase of the QC-QA procedure was an assessment of sample precision,
which is presented in Table 9.  The sample precision was determined from
duplicate samples analyzed on each system during sections I8SI9S at the
beginning of the survey and I4I5W about half way through the survey.  The pooled
standard deviation (Sp2), shown in Table 9, is the square root of the pooled
variance according to Youden (1951) where K is the number of samples with one
replicate analyzed on each system, n is the total number of replicates analyzed
from K samples, and n - K is the degree of freedom (d.f.) for the calculation.
Precision was calculated this way because TCO2 was analyzed on two different
systems, and an estimate of sample precision independent of the analytical
system was required.  Hence Sp2 is the most conservative estimate of precision
and includes all sources of random and systematic error (bias).  Bias between
systems would increase the imprecision of the measurements, but the excellent
agreement between the Sp2 values for natural seawater samples (Table 9) and the
high precision of the CRM differences confirms the virtually uniform response,
accuracy, and high precision of both systems during the survey.  This finding
confirms that the precision of the TCO2 analyses during the Indian Ocean CO2
survey was ±1.20 µmol/kg.


TABLE 9: Precision of discrete TCO2 analyses during Indian Ocean CO2 survey
                         _____________________________

                          Section  Sp2  (K,  n,  d.f)
                          -------  ------------------
                          I8SI9S   1.26 (15, 30, 15)
                          I4I5W    0.91 (21, 42, 21)
                          CRM      1.21
                         _____________________________


The next phase of the QC-QA procedure was the comparison of replicate samples
analyzed at sea and in the shore-based laboratory.  Samples from every cruise
were analyzed at sea by continuous gas extraction/coulometry, and later, after
storage, duplicate samples were analyzed on shore by vacuum extraction/manome-
try.  The results of the analyses are summarized in Table 10.


TABLE 10: Mean Difference [TCO2(S-SIO)] and standard deviation of the dif-
          ferences [S.D.(S-SIO)] between at-sea TCO2 by coulometry and on-
          shore TCO2 by manometry on aliquots of the same sample from Indian 
          Ocean CO2 survey, and the mean replicate precision [S.D.(SIO)] of 
          the manometric analyses
          __________________________________________________________________

           Section  Pairs Analyzed  TCO2(S-SIO)  S.D.(S-SIO)  S.D.(SIO) (a)
                         (n)         (µmol/kg)    (µmol/kg)    (µmol/kg)
           -------  --------------  -----------  -----------  -------------
           I8SI9S         23           -4.14        1.80          0.82
           I9N            24           -1.96        1.67          0.80
           I8NI5E         17           -4.80        2.87          1.31
           I3             29           -3.29        1.26          0.82
           I4I5W          16           -2.95        1.40          1.30
           I7N            13           -5.37        1.92          1.40
           I1             26           -5.59        1.38          1.05
           I10             8           -4.94        1.52          1.28
           I2             10           -4.42        1.50          0.83
           n             166            9           9             9
           ----------------------------------------------------------------
           Mean                        -4.16        1.70          1.07
           S.D.                         1.21        0.49          0.25
          __________________________________________________________________
           (a) Each on-shore TCO2 by manometry is always the mean of two
               analyses (see text).


In general, the reproducibility and the uniformity of the data as a whole, and
specifically, the high precision of the manometric analyses shown in Table 10,
indicate that the collection and return of the "Keeling samples" was
successfully performed by each of the measurement groups.  Poor sampling or
storage techniques would probably have been manifested in a much higher
imprecision for the on-shore replicate analyses and in the differences between
the at-sea and on-shore analyses.  However, the negative mean difference (4.16 ±
1.21, n = 9) for the Indian Ocean sections was greater than the mean difference
for WOCE sections in other oceans (-1.36 ± 1.37 µmol/kg, n = 22).  The accuracy
of the CRM analyses, the tendency for the coulometric analyses to give slightly
lower results, and the reproducibility of the at-sea and on-shore differences
are similar everywhere, but the magnitude of the Indian Ocean difference is
clearly the largest observed to date.  Even if the consistent and slightly
negative difference for the CRM is taken into account (-0.86 µmol/kg), the at-
sea coulometric measurements are approximately 2 µmol/kg lower than the
manometric method.  A suite of samples from the 1997 North Atlantic sections
remains to be analyzed.  Until these analyses are completed and a thorough
statistical evaluation of the entire CO2 survey data set is made, the
explanation of the at-sea and on-shore differences, including those found for
the Indian Ocean, is not possible.

An additional step in the QA-QC was also undertaken.  Inspection of Fig. 1 shows
points where the cruise tracks cross or nearly cross.  The agreement between
TCO2 measurements made at these crossover locations (± 100 km) on different
cruises was examined by assuming that the temporal and spatial variations in
deep-ocean TCO2 are small relative to the measurement accuracy and precision.
Hence, deep ocean waters should have the same TCO2 at different times in the
absence of internal vertical motion, and because deep ocean motion probably
occurs along constant density surfaces (isopycnals), the comparisons of TCO2
measurements were made with reference to density and not depth.  Appendixes B
and D (Johnson at al. 1998 and Sabine et al. 1999) give a complete description
of the statistical procedures used to make the crossover comparisons.  Briefly,
crossover points were selected for comparison of water samples collected below
2500 m.  A smooth curve was fit through the TCO2 data as a function of the
density anomaly referenced to 3000 dbar (sigma3) using Cleveland's LOESS
smoother (Cleveland and Devlin 1988).  A separate fit was performed for the data
collected at each of the two intersecting crossover points, but the same tension
parameter was used for all of the crossover points so that the smoothing
function was consistently applied to all crossover locations.  The difference
between the two smoothed curves was evaluated at 50 evenly spaced points
covering the density range where the two data sets overlapped.  A mean and
standard deviation for the 50 comparisons was calculated for each crossover
point.  For TCO2, differences never exceeded 3 µmol/kg, and the overall mean and
standard deviation of the differences was -0.78 ± 1.74 µmol/kg.  The latter
differences were consistent with the overall precision of the CRM analyses (±
1.2 µmol/kg).

Tables 8 10 show an internally consistent TCO2 data set for the Indian Ocean
with excellent accuracy with respect to the CRM certified values, consistently
good precision, no analytical bias between the coulometric titration systems,
and crossover agreement to within the precision of the method.  However, the
agreement between the at-sea and on-shore analyses is not as good as for earlier
WOCE sections from other oceans (i.e., the Pacific and the South Atlantic).
Based on the accuracy of the CRM analyses and the high precision of the sample
analyses, the TCO2 data were not corrected in any way and were deemed to meet
survey criteria for accuracy and precision.


3.3.  Total Alkalinity Measurements

Total alkalinity was measured on 18,928 samples using two closed-cell automated
potentiometric titration systems (hereafter designated as MATS) developed at the
University of Miami.  The MATS are described by Millero et al. (1993) and by
Millero et al. (1998).  The latter reprinted in Appendix C of this document,
completely describes the Indian Ocean Survey TALK measurements and results.
Briefly, the MATS consisted of three parts: a water-jacketed, fixed-volume
(about 200 mL determined to ± 0.05 mL) closed Plexiglass sample cell, a Metrohm
model 665 Dosimat titrator, and a pH meter (Orion, Model 720A), the last two
controlled by a PC.  The titration cell was similar to those used by Bradshaw
and Brewer (1988), but had a greater volume to improve the precision of the
measurements.  The cell was equipped with flush-mounted fill and drain valves to
increase the reproducibility of the cell volume.  The cell, titrant burette, and
sample container were held at a temperature of 25 ± 0.01°C using a constant
temperature bath (e.g., Neslab, Model RTE 221).

A Lab Windows C program was used to run the titrators, record the volume of
titrant added, and record the measured electromagnetic fields (emf) of the
electrodes through RS232 serial interfaces.  Two electrodes were used in each
cell: a ROSS glass pH electrode (Orion, Model 810100) and a double-junction
Ag/AgCl reference electrode (Orion, Model 900200).  The specific electrodes used
during the Indian Ocean survey were selected after careful screening for non-
Nernstian behavior.  Only those electrodes which gave TCO2 results in good
agreement with TCO2, as determined coulometrically, were used (Sect. 3.2).

Seawater samples were titrated by adding increments of HCl until the carbonic
acid endpoint of the titration was exceeded.  During a titration, the emf
readings were monitored until they were stable (± 0.09 mV).  Sufficient volume
of acid was added to increase the emf by preassigned increment (~13 mV) in order
to give an even distribution of data points over the course of a full titration,
which consists of 25 data points.  A single titration takes about 20 min.  A
FORTRAN computer program based on those developed by Dickson (1981) and by
Johansson and Wedborg (1982) was used to calculate the carbonate parameters.
The pH and pK of the acids used in the program are on the seawater scale, and
the dissociation constants for carbonic acid were taken from Dickson and Millero
(1987).  For further details see Appendix C and DOE (1994).

The titrant (acid) used throughout the cruises was prepared prior to the cruise,
standardized, and stored in 500-mL borosilicate glass bottles for use in the
field.  The 0.25-M HCl acid solution was prepared by dilution of 1-M HCl in
0.45-M NaCl to yield a solution with total ionic strength similar to that of
seawater of salinity 35.0 (I = 0.7 M).  The acid was standardized by coulometry
(Taylor and Smith 1959; Marinenko and Taylor 1968), and was also checked by
independent titration in A. Dickson's laboratory at SIO.  The independent
determinations agreed to ± 0.0001 M, which corresponds to an uncertainty in TALK
of ~ 1 µmol/kg.  The Dosimat titrator burettes were calibrated with Milli-Q
water at 25°C to ± 0.0005 mL.

While CRM samples were available to the TCO2 analysts from the beginning of the
measurement program in 1990, the Indian Ocean cruises were the first to have a
certified alkalinity standard as well.  Hence, the accuracy of the method was
checked in the laboratory by analyzing CRM samples from batches 23, 24, 26, 27,
29, and 30 and comparing the analyzed values with the certified TALK determined
by A. Dickson at SIO (in the same manner as for TCO2).  These results are
summarized in Table 11 (see also Appendix C).  The mean difference between the
MATS measurements in the laboratory and the certified TALK values was -0.8
µmol/kg for CRM samples with a concentration range approximately one-half as
large as the range of a typical seawater profile.  The excellent agreement
indicated that the CRM concept for alkalinity was valid and that the methodology
for TALK was ready for the Indian Ocean survey.  The results for the at-sea
measurements of the CRM samples have been extracted from Table 2 of Appendix C,
summarized, and are given in Table 12.


TABLE 11: Mean analytical difference (TALK) between analyzed and certified
          TALK for CRM used during Indian Ocean CO2 survey
          ____________________________________________________________________

           Batch  Salinity  Certified  values    MATS mean TALK   delta TALK
                              TCO2      TALK        (µmol/kg)    (MATS - CRM)
                            (µmol/kg) (µmol/kg)
           -----  --------  --------- ---------  --------------  ------------
            23     33.483    1993.10   2212.7        2213.7          1.0
            24     33.264    1987.53   2215.5        2215.8          0.3
            26     33.258    1978.34   2176.6        2175.1         -1.5
            27     33.209    1988.10   2214.9        2214.3         -0.6
            29     33.701    1902.33   2184.8        2182.3         -2.5
            30     33.420    1988.78   2201.9        2200.5         -1.4
           Range    0.492      90.77     38            40.7          3.5
           Mean                                                     -0.8
          ____________________________________________________________________


The analytical differences are for the most part within the precision of the
measurements (~ 2-5 µmol/kg) except for the I7N Section.  The larger at-sea
differences were attributed to operator error or procedures and to uncertainties
in the volume of cells, especially after repairs due to leakage, breakage, or
repositioning the electrodes after changing the inner filling solutions.
Variations between different MATS systems used on a single cruise were corrected
using the adjustments required to reproduce the values assigned for the CRM (see
Table 11).  The at-sea sample titrations were corrected using the results of the
at-sea CRM analyses.  For TALK, the calibration factor (CF) used to correct the
at sea measurements was

                CF = TALK (meas., CRM) - CRM (certified value),

and the corrected TALK (TALKc) was

               (TALKc) = TALK (meas., Spl) x [ CRM / (CRM + CF)],

where CRM was the certified TALK and Spl was the measured sample TALK.

The overall precision of TALK determinations during the Indian Ocean survey was
± 4.2 µmol/kg.  The precision of the potentiometric pH and TCO2 measurements are
given in Table 3 of Appendix C.


TABLE 12: Mean analytical difference (TALK) between analyzed and certified
          TALK for each section during Indian Ocean CO2 survey
          _____________________________________________________________

           Batch  Section  Certified  MATS mean   S.D. (n)    ∆ TALK
                             TALK       TALK     (µmol/kg)  (MATS-CRM)
                           (µmol/kg)  (µmol/kg)              (µmol/kg)
           -----  -------  ---------  ---------  ---------  ----------
            23    I8SI9S    2212.7     2221.5     5.1 (49)     8.8
            23    I9N       2212.7     2216.2     3.3 (138)    3.5
            23    I8NI5E    2212.7     2211.6     4.9 (80)    -1.1
            23    I3        2212.7     2215.4     1.4 (65)     2.7
            26    I3        2176.6     2178.0     1.2 (30)     1.4
            26    I5WI4     2176.6     2182.6     3.8 (79)     6.0
            26    I7N       2176.6     2184.0     5.7 (59)     7.4
            27    I7N       2214.9     2221.5     3.1 (8)      6.6
            23    I7N       2212.7     2222.4     7.4 (10)     9.7
            27    I1        2214.9     2219.4     3.9 (244)    4.5
            27    I10       2214.9     2212.9     4.0 (62)    -2.0
            27    I2        2214.9     2219.4     4.5 (67)     4.5
            n                                     891         12
          _____________________________________________________________


TALK was also checked at the crossover locations of two cruises in the same way
as TCO2.  The agreement between the corrected TALK measurements made at the
crossover locations (± 100 km) on different cruises was examined by assuming
that the temporal and spatial variations of the deep-ocean TALK were small
relative to measurement accuracy and precision.  Hence, deep ocean waters should
have the same TALK at different times in the absence of internal vertical
motion, and because deep ocean motion probably occurs along constant-density
surfaces (isopycnals), the comparisons of TALK measurements were made with
reference to density and not depth.  Appendixes C and D give a description of 
the statistical procedures used to make the crossover comparisons.  For water
samples collected below 2500 m, a smooth curve was fit through the TALK data as
a function of the density anomaly referenced to 3000 dbar (sigma3) using
Cleveland's LOESS smoother (Cleveland and Devlin 1988).  A separate fit was
performed on the data collected at each of the two intersecting crossover
points, with the same tension parameter being used for all of the crossovers so
that the smoothing function was consistently applied.  The difference between
the two smoothed curves was evaluated at 50 evenly-spaced points covering the
density range where the two data sets overlapped.  Mean and standard deviations
for the differences at the 50 points were calculated for each crossover point.
For TALK, differences never exceeded 6 µmol/kg, and the overall mean and
standard deviation of the differences was 2.1 ± 2.1 µmol/kg.  The latter were
consistent with the overall precision of the CRM analyses (± 4 µmol/kg).

Table 13 is a final summation of the inorganic carbon analytical work completed
during the Indian Ocean CO2 survey from 1994 to 1996.


TABLE 13: Final count of carbonate system parameter (CSP) analyses during
          Indian Ocean CO2 survey
                      _______________________________________

                                   No. of CSP determinations
                       Parameters   Discrete   CRM   Total
                       ----------   --------  -----  ------
                        TCO2         18,963     983  19,946
                        TALK         18,928     949  19,877
                        Total        37,891   1,932  39,823
                      ______________________________________


3.4.  Carbon Data Synthesis and Analysis

In accordance with one of the stated goals of the program, an evaluation of the
data set with respect to estimated anthropogenic CO2 distributions in the Indian
Ocean has been completed and published by Sabine et al. (1999) (see Appendix D).
The document is appended to this report as Appendix D.  Additional crossover
comparisons of the survey data with data gathered in the 1980s and in 1993 by
French scientists are included.  Briefly, the sequestering of anthropogenic CO2
has been estimated by comparing the Indian Ocean survey results with the Indian
Ocean GEOSECS expedition data from 1977 to 1978.  Although CRM samples were not
available for evaluating the earlier data, statistical methods were used to fit
these data and correct for calibration offsets so that they could be compared
with the current survey data.  The data analysis was complicated by regions of
pronounced denitrification (Arabian basin) and other regional variations that
had to be considered and quantified.  In summary, the estimate of the
anthropogenic inventory was relatively small in the Indian and Southern Oceans,
with anthropogenic carbon uptake lower by a factor of 2 compared to that of the
Atlantic Ocean.  Importantly, discrepancies between model and data-based
estimates were found especially for the Southern Ocean where carbon uptake
appears to have been traditionally overestimated by the extant circulation
models. (See Appendix D for further details.)  The initial data synthesis work
indicates that the survey data will provide an important baseline with respect
to future studies and that the spatial distribution of anthropogenic carbon can
be an important tool for understanding model-based carbon uptake estimates and
the response of models to atmospheric increases in CO2.


3.5.  Radiocarbon Measurements

Full information on the radiocarbon measurement method, instrumentation, and
results can be found in Appendix E of this document.



4.  DATA CHECKS AND PROCESSING PERFORMED BY CDIAC

An important part of the numeric data packaging process at the Carbon Dioxide
Information Analysis Center (CDIAC) involves the quality assurance (QA) of data
before distribution.  Data received at CDIAC are rarely in a condition that
would permit immediate distribution, regardless of the source.  To guarantee
data of the highest possible quality, CDIAC conducts extensive QA reviews that
involve examining the data for completeness, reasonableness, and accuracy.  The
QA process is a critical component in the value-added concept of supplying
accurate, usable data for researchers.

The following information summarizes the data processing and QA checks performed
by CDIAC on the data obtained during the R/V Knorr cruise along WOCE Sections
I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, I10, and I2  in the Indian Ocean.

1.  The final carbon-related data were provided to CDIAC by the ocean carbon
    measurement PIs listed in Table 5.  The final hydrographic and chemical
    measurements and the station information files were provided by the WOCE
    Hydrographic Program Office (WHPO) after quality evaluation.  A FORTRAN 90
    retrieval code was written and used to merge and reformat all data files.

2.  Every measured parameter for each station was plotted vs depth (pressure) to
    identify questionable outliers using the Ocean Data View (ODV) software
    (Schlitzer 2001) Station Mode (Fig. 3).

3.  The section plots for every parameter were generated using the ODV's Section
    Mode in order to map a general distribution of each property along all 
    Indian Ocean sections (Fig. 4).

4.  To identify "noisy" data and possible systematic, methodological errors,
    property-property plots for all parameters were generated (Fig. 5), 
    carefully examined, and compared with plots from previous expeditions in the 
    Indian Ocean.

5.  All variables were checked for values exceeding physical limits, such as
    sampling depth values that are greater than the given bottom depths.

6.  Dates, times, and coordinates were checked for bogus values (e.g., values of
    MONTH < 1 or > 12; DAY < 1 or > 31; YEAR < 1994 or > 1996; TIME < 0000 or >
    2400; LATITUDE <  70.000 or > 60.000; LONGITUDE < 19.000 or > 119.000.

7.  Station locations (latitudes and longitudes) and sampling times were 
    examined for consistency with maps and cruise information supplied by PIs.

8.  The designation for missing values, given as  9.0 in the original files, was
    changed to  999.9 for the consistency with other oceanographic data sets.



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List of CO2 measurement group members participating in the Indian Ocean CO2
Survey aboard the R/V Knorr in 1994 1996 (CO2 group leaders for each section 
are given in Table 4 in the text)

            ________________________________________________________

             Section  Name                  Sponsoring  Affiliation
                                            institute
             -------  --------------------  ----------  -----------
             I8SI9S   Haynes, Charlotte H    BNL         WDNR
                       Haynes, Elizabeth M   BNL         RU
                       Wysor, Brian S.       BNL         SHC
             I9N      Dorety, Art            PU          PU
                       Kozyr, Alex           PU          ORNL/CDIAC
                       Suntharalingam, Parv  PU          PU
             I8NI5E   Parks, Justine         UH          SIO
                       Popp, Brian           UH          UH
                       Schottle, R.          UH          UH
             I3       Aicher, Jennifer       RSMAS       RSMAS
                       Edwards, Christopher  RSMAS       RSMAS
                       Krenisky, Joann       RSMAS       RSMAS
             I4I5W    Lewis, Ernie           BNL         BNL
                       Pikanowski, Linda     BNL         SHML
                       Zotz, Michelle        BNL         BNL
             I7N      Adams, Angela          UH          UH
                       Angeley, Kelly        UH
                       Phillips, Jennifer    UH          UHH
             I1       Amaoka, Toshitaka      WHOI        GSEESHU
                       Okuda, Kozo           WHOI        GSEESHU
                       Ording, Philip        WHOI        WHOI
             I10      Boehme, Sue            PU          RU
                       Markham, Marion       PU          PU
                       Mcdonald, Gerard      PU          PU
             I2       Admas, Angela          UH          UH
                       Cipolla, Cathy        UH          GSOURI
                       Phillips, Jennifer    UH          UHH
            ________________________________________________________



Participating institutions:

BNL         Brookhaven National Laboratory
ORNL/CDIAC  Oak Ridge National Laboratory/Carbon Dioxide Information Analysis
            Center
GSEESHU     Graduate School of Environmental and Earth Science, Hokkaido
            University
GSOURI      Graduate School of Oceanography, University of Rhode Island
PU          Princeton University
RSMAS       Rosenstiel School of Marine and Atmospheric Science, University of 
            Miami
RU          Rutgers University
SHC         South Hampton College
SHML        Sandy Hook Marine Laboratory
SIO         Scripps Institution of Oceanography
UH          University of Hawaii, Honolulu
UHH         University of Hawaii at Hilo
WDNR        Wisconsin Department of Natural Resources
WHOI        Woods Hole Oceanographic Institution












                                  APPENDIX B:

                        REPRINT OF PERTINENT LITERATURE




Johnson, K.M. , A.G. Dickson, G. Eischeid, C. Goyet, P. Guenther, R.M. Key, 
F.J. Millero, D. Purkerson, C.L. Sabine, R.G. Schottle, D.W.R. Wallace, R.J. 
Wilke and C.D. Winn, Coulometric total carbon dioxide analysis for marine 
studies: assessment of the quality of total inorganic carbon measurements
made during the US Indian Ocean CO2 Survey 1994-1996, Marine Chemistry 63:21-37.





Marine Chemistry 
63(1998) 21-37


           COULOMETRIC TOTAL CARBON DIOXIDE ANALYSIS FOR MARINE STUDIES:
          ASSESSMENT OF THE QUALITY OF TOTAL INORGANIC CARBON MEASUREMENTS
                MADE DURING THE US INDIAN OCEAN CO2 SURVEY 1994-1996

          Kenneth M. Johnson(a)*, Andrew G. Dickson(b), Greg Eischeid(c),
  Catherine Goyet(c), Peter Guentherb(b), Robert M. Key(d), Frank J. Millero(e), 
        David Purkerson(e), Christopher L. Sabine(d), Rolf G. Schottle(f),
      Douglas W. R. Wallace(a), Richard J. Wilke(a) and Christopher D. Winn(f)

(a) Department of Applied Science, Brookhaven National Laboratory, Upton, NY 
    11973, USA
(b) Scripps Institution of Oceanography, University of California, San Diego, La 
    Jolla San Diego, CA 92093, USA
(c) Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
(d) Geology Department, Princeton University, Princeton, NJ 08544, USA
(e) Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, 
    Miami, FL 33149, USA
(f) Department of Oceanography, University of Hawaii, Honolulu, HI 96822, USA

*Corresponding author. Tel.: +1-516-344-5668; Fax: +1-516-344-3246

Received 8 January 1998; accepted 6 May 1998. Available online 8 December 1998.
0304-4203/98/$ - see front matter (c) 1998 Elsevier Science B.V. 
All rights reserved. 
PII: S0304-42039800048-6





ABSTRACT

Two single-operator multiparameter metabolic analyzers (SOMMA)-coulometry 
systems (I and II) for total carbon dioxide (TCO2) were placed on board the R/V 
Knorr for the US component of the Indian Ocean CO2 Survey in conjunction with 
the World Ocean Circulation Experiment-WOCE Hydrographic Program (WHP). The 
systems were used by six different measurement groups on 10 WHP Cruises 
beginning in December 1994 and ending in January 1996. A total of 18,828 
individual samples were analyzed for TCO2 during the survey. This paper assesses 
the analytical quality of these data and the effect of several key factors on 
instrument performance. Data quality is assessed from the accuracy and precision 
of certified reference material (CRM) analyses from three different CRM batches. 
The precision of the method was 1.2 µmol/kg. The mean and standard deviation of 
the differences between the known TCO2 for the CRM (certified value) and the CRM 
TCO2 determined by SOMMA-coulometry were -0.91±0.58 (n=470) and -1.01±0.44 
(n=513) µmol/kg for systems I and II, respectively, representing an accuracy of 
0.05% for both systems. Measurements of TCO2 made on 12 crossover stations 
during the survey agreed to within 3 µmol/kg with an overall mean and standard 
deviation of the differences of -0.78±1.74 µmol/kg (n=600). The crossover 
results are therefore consistent with the precision of the CRM analyses. After 
14 months of nearly continuous use, the accurate and the virtually identical 
performance statistics for the two systems indicate that the cooperative survey 
effort was extraordinarily successful and will yield a high quality data set 
capable of fulfilling the objectives of the survey.


AUTHOR KEYWORDS: total carbon dioxide (TCO2); single-operator multiparameter 
                 metabolic analyzers (SOMMA) coulometry; marine studies

INDEX TERMS:     reproductive toxicity; boron




ARTICLE OUTLINE

1. Introduction
2. Materials and methods
2.1. Preparations
2.2. Selection of cell assemblies
2.3. At-sea operations
2.4. Calculation of results
2.5. Assessment of analytical accuracy
2.6. Data distribution
3. Results
3.1. To-deliver pipette volume
3.2. CRM analyses and system accuracy
3.3. System repeatability and precision during the survey
4. Discussion
5. Crossover analysis
6. Conclusions
Acknowledgements
References




1. INTRODUCTION

Between 1990 and 1997 an international effort was made to determine the global 
oceanic distribution of inorganic carbon in conjunction with the World Ocean 
Circulation Experiment (WOCE) Hydrographic Programme (WHP). This effort is 
referred to as the Global Survey of CO2 in the oceans, and it is an integral 
part of the Joint Global Ocean Flux Study (JGOFS). The goals of this survey are 
to:

1. Accurately determine the oceanic distribution of dissolved inorganic carbon,

2. Quantify the uptake of anthropogenic carbon dioxide by the oceans to better 
   predict future atmospheric carbon dioxide levels,

3. Provide a global description of anthropogenic carbon dioxide in the oceans to 
   aid development of a 3-dimensional model of the oceanic carbon cycle,

4. Characterize the transport of carbon dioxide between the ocean and the 
   atmosphere and the large scale (e.g., meridional) transports of carbon 
   dioxide within the ocean.

The survey has acquired a global data set of profile measurements of dissolved 
carbon dioxide parameters on both zonal and meridional oceanographic transects 
throughout the world's oceans. With reference to program goals, Bates et al. 
(1996) found that for mixed layer waters the average rate of increase in CO2 
concentration due to the uptake of anthropogenic CO2 was 1.7 µmol/kg/yr (<0.1%). 
This rate of increase establishes a natural target for the accuracy of the TCO2 
measurements. The distribution of this 'excess' CO2 signal is not uniform 
spatially, and it is masked by variability in CO2 concentrations arising from 
natural biological and physicochemical processes. Hence, the goals of the 
program imply that measurements must be extremely accurate (0.1% or better) and 
spatially extensive. A large part of the US contribution to this survey has been 
conducted by a team of investigators supported by the US Department of Energy 
(DOE). This team has developed certified reference materials (Dickson, 1990), 
instrumentation (Johnson and Wallace, 1992), a set of standard operating 
procedures (DOE, 1994) and, to a large extent, shared a common approach to the 
measurement program.

This paper presents the DOE team effort which sampled the Indian Ocean for 
inorganic carbon during the course of approximately 1 year. All the measurements 
were made aboard a single research vessel during sequential cruises which 
allowed the investigators to share equipment and procedures to an unprecedented 
extent. This paper concentrates on estimating the accuracy of the shipboard 
determinations of the total dissolved inorganic carbon concentration of 
seawater. This parameter was established at the onset of the survey as the 
primary carbonate system parameter because its concentration should change in 
response to anthropogenic CO2 uptake and it had the highest potential for 
measurement accuracy. Our results highlight some factors which affect the 
accuracy of this measurement. The Indian Ocean Survey aboard the R/V Knorr 
encompassed the cruise legs shown in Fig. 1 in the sequence given in Table 1. 
Fig. 1 also gives the location of the crossover points (cruise track 
intersections) where comparisons of the reproducibility of the TCO2 analyses 
were made. The six survey groups measured two water column carbonate system 
parameters, total dissolved carbon dioxide (TCO2) and total alkalinity (TA), and 
assisted with the operation of an underway pCO2 (surface) system. This paper 
focuses on TCO2 by coulometry, while the total alkalinity (TA) and partial 
pressure of CO2 (pCO2) measurements are the subject of companion papers and 
reports (Millero et al., 1998; Sabine and Key, 1998).


Fig. 1.  The cruise tracks for the nine legs of the US Indian Ocean WOCE Survey 
         1994-1996. Crossover points between the various legs are marked with a 
         square and numbered. These intersection points and crossovers are 
         referred to in Table 4.


TABLE 1: Approximate dates and ports of call for the 9 legs of the Indian Ocean 
         CO2 Survey, and the measurement groups responsible for the 
         determination of the carbonate system parameters
______________________________________________________________________________

 Leg            Dates          From        To          Group         Duration 
           Start     End                                             (days) 
 --------  --------  --------  ----------  ----------  ------------  --------
 I8SI9S    12r1r94   1r19r95   Fremantle   Fremantle   BNL             50 
 I9N       1r24r95   3r6r95    Fremantle   Colombo     Princeton U.    42 
 I8NI5E    3r10r95   4r16r95   Colombo     Fremantle   U. of Hawaii    38 
 I3        4r20r95   6r7r95    Fremantle   Port Louis  U. of Miami     49 
 I5WI4     6r11r95   7r11r95   Port Louis  Port Louis  BNL             31 
 I7N       7r15r95   8r24r95   Port Louis  Matrah      U. of Hawaii    41 
 I1        8r29r95   10r18r95  Matrah      Singapore   WHOI            51 
 Dry Dock  10r19r95  11r5r95   Singapore                               17 
 I10       11r6r95   11r24r95  Singapore   Singapore   Princeton U.    19 
 I2        11r28r95  1r19r96   Singapore   Mombasa     U. of Hawaii    53 
______________________________________________________________________________
 Abbreviations: BNL, Brookhaven National Laboratory; U, University; 
                WHOI, Woods Hole Oceanographic Institution. 



2. MATERIALS AND METHODS

2.1. PREPARATIONS

The total carbon dioxide concentration (TCO2) was determined using two single-
operator multiparameter metabolic analyzers (SOMMA) each connected to a Model 
5011 coulometer (UIC, Joliet, IL 60434). Descriptions of the SOMMA-coulometer 
system and its calibration can be found in the works of Johnson (1995), Johnson 
and Wallace (1992), and Johnson et al. (1987) and Johnson et al. (1993). A 
schematic diagram of the SOMMA is shown in Fig. 2, and further details 
concerning the coulometric titration can be found in the works of Huffman (1977) 
and Johnson et al. (1985). Briefly, seawater fills an automated to-deliver 
sample pipette. The contents of the pipette are pneumatically injected into a 
stripping chamber containing approximately 1.2 cm3 of 8.5% (v/v) phosphoric 
acid, and the resultant CO2 is extracted, dried, and coulometrically titrated. 
Calibration is performed by titrating known masses of pure CO2 and checked by 
analyzing certified reference material (CRM). The coulometers were adjusted to 
give a maximum titration current of 50 mA, and they were run in the counts mode 
(the number of pulses or counts generated by the coulometer's voltage to 
frequency converter during the titration is displayed). In the coulometer cell, 
the acid (hydroxyethylcarbamic acid) formed from the reaction of CO2 and 
ethanolamine is titrated coulometrically (electrolytic generation of OH¯) with 
photometric endpoint detection. The systems were equipped with conductance cells 
(Model SBE-4, Sea-Bird Electronics, Bellevue, WA) for measuring salinity as 
described by Johnson et al. (1993).


Fig. 2.  SOMMA-coulometer system schematic. Carbon dioxide extracted from a 
         water sample (I) or from volume-calibrated gas sample loops filled at a 
         known pressure and temperature is degassed from the stripper (IV), 
         dried (V), and coulometrically titrated (VI). The water sample is 
         pneumatically injected from the pipette (II) into the stripper, and the 
         pure CO2 contained in the gas loops is delivered to the stripper from 
         an 8-port chromatography valve (VII) equipped with pressure and 
         temperature sensors. Salinity is measured using a conductance cell 
         (III) integrated into the SOMMA chassis. The pipette and conductance 
         cell are thermostatted and equipped with temperature sensors.


The DOE supported the construction of nine SOMMA-coulometer systems for the US 
CO2 Survey Measurement Groups in the early 1990's (Johnson and Wallace, 1992), 
and two of these systems from the DOE instrument pool were set up aboard the R/V 
Knorr in Fremantle, Australia on November 28, 1994. Before they were shipped to 
Australia, the temperature sensors were calibrated, the glassware was chemically 
cleaned and gravimetrically calibrated, the gas sample loop volumes were 
calibrated according to the procedure of Wilke et al. (1993), the coulometers 
were electronically calibrated (Johnson et al., 1993; DOE, 1994), and system 
accuracy was verified with CRM at Brookhaven National Laboratory (BNL). The same 
two systems (hereafter called I and II) were used by all measuring groups. A 
backup system (from Woods Hole Oceanographic Institution) was onboard but was 
not used. Pre-cruise preparations also included a training session for 
participants at the University of Miami in September 19-23, 1994.

Referring to Fig. 2, the analytical gases included UHP nitrogen (99.998%) for 
carrier and pneumatic gases, compressed air for the headspace gas, and 
analytical grade CO2 (99.995%) from Scott Speciality Gases (South Plainfield, 
NJ) for the calibration gas. The survey began with the use of compressed gases, 
but prior to leg I8N in April 1995, a N2 generator (TOC Model 1500, Peak 
Scientific, Chicago, IL) was placed into service. The generator provided N2 
(99.9995%, hydrocarbons<0.1 ppm, CO2<1.0 ppm) for carrier and pneumatic gases to 
both systems for the remainder of the survey. Unless otherwise stated, all other 
reagents remain as described by Johnson et al. (1993).

The BNL measurement group supplied 7 side-arm type glass titration cells (UIC, 
PN 200-034), 7 silver electrodes (PN 101-033), and 5 rubber cell caps (PN 192-
005). A platinum electrode (PN 101-034), temperature sensor (PN LM34CH, National 
Semiconductor, Santa Clara, CA), and a teflon inlet tube were mounted in each 
cap. Together, the cell and cap comprise the cell assembly shown in Fig. 3. For 
this paper, each cell assembly is assigned an 'age' or lifetime which is 
measured in minutes (chronological age) or by the mass of carbon titrated in mg 
C (carbon age) from the time when current is first applied to the assembly (cell 
birth) until the current is turned off (cell death). The software continuously 
records the chronological and carbon ages.


Fig. 3.  The titration cell assembly and the cathodic and anodic half reactions 
         for the coulometric titration of the H+ from the acid formed by the 
         reaction of CO2 and ethanolamine.


2.2. SELECTION OF CELL ASSEMBLIES

The performance of individual cell assemblies (Fig. 3) varies widely (K.M. 
Johnson, unpublished data). Unacceptable assemblies exhibit high blanks, 
prolonged blank determinations (>2 h), reduced accuracy or precision, or become 
noisy early in their lifetime. Acceptable assemblies stabilize quickly (within 
60 min) and function well for periods exceeding 24 h. Cell behavior will be 
discussed elsewhere, but our experience suggests several factors play a role: 
quality of the reagents; quality (purity) of the carrier gases; damage to the 
platinum electrode; and perhaps the porosity of the cell frit. Therefore, a 
systematic effort was made at the beginning of leg I8SI9S to select 
satisfactorily performing cell assemblies using pretested reagents and carrier 
gas sources known to be uncontaminated. During this first leg, the assemblies on 
hand were evaluated for conformance to the following empirical criteria.

(1) Cell assemblies should attain a blank of ≤0.005 µmol C/min within 90 min of 
    cell birth. Satisfactory assemblies usually exhibit a 15-25% decline in the 
    blank with each successive determination.

(2) The gas calibration factor, which is the ratio of an accurately known mass 
    of CO2 to the mass of this gas determined coulometrically, should be 
    1.004±0.0015 (recoveries of 99.6%).

(3) Titrations of CO2 extracted from gas sample loops (gas calibration) or 
    pipettes of 20 cm3 (sample analysis) should take 9-12 min.

(4) Cell assemblies, which repeatedly exhibit titrations longer than 20 min (no 
    endpoint) before their carbon age reached 30 mg C titrated, were considered 
    defective. An occasional failure to attain an endpoint after the carbon age 
    exceeds 30 mg C was interpreted to mean that the cell frit required cleaning 
    with 6 N HNO3 and retesting.

Based on these criteria, three assemblies (2 primary and a third as backup) were 
found to be acceptable during the first leg, and these assemblies were used 
throughout the survey (at the midpoint of the survey an additional assembly was 
placed into service).


2.3. AT-SEA OPERATIONS

The following TCO2 sampling and measurement practices were followed throughout 
the survey.

(1) The daily sequence of analytical operations for each system as described in 
    the SOMMA operator's manual (Johnson, 1995) consisted of changing the cells 
    and drying agents, determining the blank, running test seawater samples, 
    calibrating the system using pure CO2 (gas calibration), analyzing samples, 
    and analyzing certified reference material (CRM) at the beginning and end of 
    the cell lifetime.

(2) A complete deep vertical profile for TCO2 and TA consisted of 36 samples. A 
    lesser number of samples were drawn at shallower stations. Complete profiles 
    were taken at every other station, and if time permitted, additional 
    truncated profiles (0-1000 m) were taken. TCO2 samples always coincided with 
    14C samples. Samples were drawn from 10-l Niskin bottles according to DOE 
    (1994).

(3) Samples for TCO2 were collected in 300 cm3 BOD-type glass bottles. They were 
    poisoned with a saturated HgCl(2) solution (200-400 µl) upon collection. The 
    appropriate correction factors for dilution were applied by the measurement 
    groups according to DOE (1994).

(4) Sample bottles were rinsed and then allowed to overflow by at least 1/2 
    volume before poisoning. Prior to April 1995, a glass stopper was inserted 
    into the full BOD bottle. After April 1995, a headspace of approximately 4 
    cm3 was created before poisoning and stoppering. This was done in a 
    reproducible manner by squeezing the filling tube shut before withdrawing it 
    from the bottle. This change was made to ensure that no HgCl(2) was 
    displaced by the stopper, and to allow for water expansion. The gas-liquid 
    phase ratio was approximately 1.3%. A correction (±0.5 µmol/kg) for the 
    reequilibration of the liquid with the gas phase was applied by the 
    measurement groups according to DOE (1994).

(5) To estimate sample precision, duplicate samples were normally collected at 
    surface, mid depth, and at the deepest depth. The duplicate analyses were 
    interspersed with the analysis of the other profile samples with a minimum 
    of 2 h and up to 12 h between duplicate analyses. Because the duplicate 
    analyses were separated in time, these data could potentially detect drift 
    (decreased precision) as the cell aged. Every effort was made to run each 
    station profile on a single cell assembly, and to limit the cell lifetime to 
    ≤35 mg C.

(6) Although salinity was determined by the SOMMA-coulometer systems, post-
    cruise sample density was calculated using bottle salinities supplied by the 
    chief scientists. However, SOMMA-based salinities were often compared to the 
    real-time CTD salinities to spot bottle mistrips during the taking of the 
    vertical profiles. The agreement between SOMMA-based and CTD salinities was 
    ±0.02 or better.

(7) To monitor the volume of the SOMMA pipettes, they were periodically filled 
    with deionized water at known temperatures, and their output collected in 
    preweighed serum bottles. The bottles were sealed immediately and stored 
    until they were reweighed at BNL on a model R300S (Sartorius, Göttingen, 
    Germany) balance. The mass of water corrected for buoyancy was used to 
    calculate the to-deliver pipette volume (V(cal), Eq. 3) according to DOE 
    (1994).

(8) After use, cells were cleaned with deionized water followed by an acetone 
    rinse of the glass frit. Before reuse, they were dried at 55°C for at least 
    12 h. Cell caps and the platinum electrodes were thoroughly washed with 
    deionized water and dried at 55°C for at least 6 h before reuse.

(9) Duplicate samples from approximately 3000 m and 20 m were regularly 
    collected for shore-based reference analyses of TCO2 by vacuum 
    extraction/manometry by C.D. Keeling at the Scripps Institution of 
    Oceanography (SIO). Between 2 and 5% of the samples analyzed at sea will be 
    analyzed at SIO and reported elsewhere.


2.4. CALCULATION OF RESULTS

For the coulometric determination, the mass of carbon titrated from CO2 
extracted from the gas sample loops or a water sample in µmol of carbon is given 
by M according to:

      M=[Counts/4824.45-(Blank x t(t))-(Int(ec) x t(i))]/Slope(ec),     (1)

where Counts is the coulometer display, i.e., the number of pulses accumulated 
by the coulometer's voltage to frequency circuit (VFC); 4824.45 (counts/µmol) is 
a scaling factor derived from the factory calibration of the VFC and the value 
of the Faraday (96,485.309 C/mol); Blank is the system blank in µmol/min; t(t) 
is the length of the titration in minutes; Int(ec) is the intercept from the 
electronic calibration of the coulometer; ti is the duration (min) of continuous 
current flow, and Slope(ec) is the slope from electronic calibration (Johnson et 
al., 1993; DOE, 1994). Electronic calibration serves as a check of the factory 
calibration. If the coulometer was perfectly calibrated, the slope and intercept 
would be 1 and 0, respectively. Typically, minor deviations from the theoretical 
slope (0.998-0.999) and intercept (0.001-0.01) are observed. The water sample 
TCO2 concentration in µmol/kg is calculated from:

               TCO2 = M x Calibration Factor x 1/(V(t)p))D+∆TCO(2),     (2)

where VT is the sample volume (to-deliver volume of the SOMMA pipette) 
calculated from:

                          V(T)=V(cal)[1+a(v)(T-T(cal)],                 (3)

and T is the analytical temperature; V(cal) is the calibrated volume of the 
pipette at the calibration temperature, T(cal); av is the coefficient of 
volumetric expansion for Pyrex glass (1.0 x 10(^-5)/deg). In Eq. 2, Calibration 
Factor is the gas calibration factor (see Eq. 4); p is the density of seawater 
from the seawater equation of state (Millero and Poisson, 1981) at the sample 
salinity and T; D is the correction due to dilution of the sample with HgCl(2) 
preservative; ∆TCO2 is the correction for the repartitioning of CO2 into the 
sample headspace according to DOE (1994). Note that correction factors D and 
∆TCO2 (Eq. 2) are not incorporated into the SOMMA software and were applied post 
cruise by the individual measurement groups.

The gas calibration factor (Calibration Factor) is the ratio of:

                                   M(calc)/M,                           (4)

where M(calc) is the mass of CO2 contained in the gas sample loop calculated 
according to DOE (1994), and M is the coulometric determination of that same 
mass from Eq. 1.


2.5. ASSESSMENT OF ANALYTICAL ACCURACY

Analytical accuracy was assessed by analyzing certified reference materials 
(CRMs). The CRMs are filtered seawater poisoned with HgCl(2). They are prepared 
in 500 cm3 bottles at the Scripps Institution of Oceanography (SIO) according to 
procedures given by Dickson (1990). The certified TCO2 value is obtained by 
analyzing a representative number of samples by vacuum extraction/manometry in 
the laboratory of C.D. Keeling at SIO. For this paper, the term analytical 
difference refers to the difference between the analyzed (by coulometry) and the 
certified value of the CRM (by manometry), i.e., at-sea accuracy is estimated 
from the analyzed TCO2-certified TCO2 differences.


2.6. DATA DISTRIBUTION

The complete data set has been submitted to the Carbon Dioxide Information 
Analysis Center (CDIAC) at the Oak Ridge National Laboratory (ORNL). CDIAC will 
issue a final data report which will detail the procedures for retrieving the 
data. The overall accuracy given below is considered final at this time, and the 
estimated precision is expected to remain unchanged. The CDIAC web address is 
http://cdiac.esd.ornl.gov.



3. RESULTS

During the survey, approximately 18,828 separate samples (not counting dupli-
cates) for TCO2, and 983 CRM were analyzed on the two systems (A. Kozyr, 
personal communication, November 1997).


3.1. TO-DELIVER PIPETTE VOLUME

Some 103 gravimetric determinations of the sample pipette volume were made on 28 
separate occasions during the survey (14 on each system). Four of the determina-
tions were rejected; two because they were exactly 1 cm3 too high with respect 
to the survey mean (likely due to failure to correctly note the tare weight 
determined prior to the cruise), and two because they were inexplicably 0.3% 
lower than the survey mean volumes (probably due to faulty sealing and evapora-
tion). There were no results from leg I8N because the gravimetric samples were 
collected incorrectly. Volume determinations should have been made at the start, 
middle, and at the end of each leg, or at least at the beginning and end of each 
leg. However, for a variety of reasons, this was not always the case. In order 
to consistently assign a pipette volume to each leg, a leg-specific volume 
(V(cal)) was obtained by averaging the volume determinations made closest to the 
beginning and end of the leg along with any made during that leg. Table 2 
presents the results for V(cal), and the chronological order of the pipette 
determinations used to calculate V(cal) are plotted in Fig. 4a for system I and 
Fig. 4b for system II. This averaging increases the number of determinations 
used to calculate V(cal), and ensures that V(cal) is based on at least two sets 
of determinations, separated in time, for all legs except the initial leg 
(I8SI9S) and leg I10 after the pipette was cleaned. Table 2 and Fig. 4a and b 
show the timing of events which could conceivably have affected pipette volume. 
For I8SI9S, the pipette volumes were determined in the laboratory prior to the 
cruise; however, the volume of system I had to be empirically redetermined at-
sea because its pipette was broken during transit. This was done as follows: 
after replacing the pipette, V(cal) was determined by simultaneously analyzing a 
replicate from a single seawater sample on systems I and II. Because V(cal) was 
well known for system II, the TCO2 concentration determined on system II was 
used to calculate the pipette volume of system I by rearranging Eq. 2 to solve 
for VT and letting VT be equal to V(cal) for the subsequent analyses on system I 
during leg I8SI9S. As Table 2 shows, numerous volume determinations were made 
for both systems I and II on succeeding legs.


TABLE 2: The leg-specific to-deliver pipette volume (V(cal)) and the calibration 
         temperature (T(cal)) for SOMMA-coulometer systems I and II during the 
         Indian Ocean Survey 1994-1996
______________________________________________________________________________

 Leg       n      V(cal)       S.D.     R.S.D.    T(cal)    Determinations 
                  (cm^3)      (±cm^3)    (%)       (C)      averaged (legs)
 ------    --     -------     ------    ------    -----     -----------------
 System I 
 I8SI9S     2     21.4609     0.0037     0.02     20.00     see text, 8S9S(e) 
 I9N        9     21.4543     0.0112     0.05     20.97     8S9S(e), 9N(e)
 Gas generator introduced as CG source
 I8NI5E     9     21.4443*    0.0021     0.01     20.97     9N(e), 3(m)
 I3        15     21.4471     0.0042     0.02     20.57     9N(e), 3(m), 4(s)
 Gas generator output pressure adjusted from 5 to 10  psi     
 I5WI4     10     21.4506*    0.0023     0.01     19.93     5W4(s,e) 
 I7N        8     21.4506     0.0032     0.02     20.36     7N(s,m,e) 
 I1         5     21.4462     0.0074     0.03     20.12     7N(e), 1(e) 
 Pipette dismounted,cleaned,and recalibrated     
 I10        5     21.4460     0.0110     0.05     20.08     10(e)     
 I2         8     21.4482     0.0091     0.04     20.08     10(e), 2(s,e)

 System II 
 I8SI9S    18     21.6388     0.0068     0.03     20.24     8S9S(s,e) 
 I9N        9     21.6360     0.0163     0.08     20.49     8S9S(e), 9N(e) 
 Gas generator introduced as CG source     
 I8NI5E     8     21.6239     0.0080     0.04     20.56     9N(e), 3(m)
 I3        14     21.6243     0.0068     0.03     20.31     9N(e), 3(m), 4(s)
 Gas generator output pressure adjusted from 5 to 10 psi 
 I5WI4     11     21.6293     0.0068     0.03     19.97     5W4(s,e) 
 I7N        8     21.6194*    0.0048     0.02     20.05     7N(s,m,e) 
 I1         4     21.6156     0.0035     0.02     20.00     7N(e), 1(e) 
 Pipette dismounted,cleaned,and recalibrated     
 I10        4     21.6269*    0.0017     0.01     19.95     10(e) 
 I2         9     21.6270     0.0028     0.01     19.94     10(e),2(s,e) 
______________________________________________________________________________
 The subscripts (s, m, or e) for the pipette volume determinations averaged 
 to calculate V(cal) signify determinations made at the start, middle, or end 
 of a leg, respectively. Values of V(cal) which are significantly different 
 from the V(cal) of the preceding leg are denoted by the asterisk.


Fig. 4.  The temporal record of the analytical performance of SOMMA-coulometer 
         system I (Fig. 4a) and II (Fig. 4b) during the Indian Ocean Survey 
         1994-1996. The top section of the three-part graphs shows the leg-
         specific pipette volumes, V(cal), as horizontal lines corresponding to 
         the duration of the individual legs, and the relative chronological 
         order of the means of the individual pipette determinations from which 
         V(cal) was calculated as open circles placed before, in the middle of, 
         or following the horizontal lines representing V(cal) (see text and 
         Table 2 for details). The middle section depicts the mean gas calibra-
         tion factors for each leg (horizontal lines), and the bottom section 
         shows the mean analytical differences for the CRM analyses assuming a 
         constant pipette volume (V(cal) for leg I8S) for the duration of the 
         survey (open circles) vs. the leg-specific V(cal) (closed circles). The 
         error bars through the plot symbols represent the S.D. of the determi-
         nations. Procedural changes (introduction of the gas generator, 
         pressure adjustments, and cleaning) which may have affected pipette 
         volume are indicated by the arrows.


For I10, data from the prior leg could not be used to calculate V(cal) because 
leg I10 took place after the pipettes had been dismounted for cleaning, which 
may have altered their volumes. On legs I5WI4 and I7N, replicate volume 
determinations were made at the beginning, middle, and end of the leg by the 
same measuring group so that V(cal) for these legs do not include results from 
preceding or succeeding legs. The survey mean pipette volumes and their standard 
deviations for systems I and II are 21.4502±0.0032 cm3 at 20.25°C (n=43) and 
21.6261±0.0028 cm3 at 20.14°C (n=56), respectively. The pooled standard 
deviation (sp^2) calculated according to Youden (1951) for the 28 sets of 
gravimetric determinations is ±0.0042 cm3. Individually, sp^2 for system I is 
±0.0049 cm3, and for system II sp^2 is ±0.0036 cm3, suggesting a very slightly 
higher precision for system II.

Significant differences at the 95% confidence level in V(cal) for comparisons 
between each leg with the succeeding leg were determined by two-tailed t-tests 
according to Taylor (1990), and are denoted by asterisks in Table 2. For the 
most part, leg to leg differences in V(cal) are not significant (significance in 
2 of 9 comparisons for each instrument), but it should be noted that for both 
systems, the differences between the initial leg (I8SI9S) pipette volumes and 
all leg-specific volumes after leg I9N are significant. In both systems, the to-
deliver pipette volume declines slightly with time. However, the decline is not 
consistent between instruments. In system I, significant decreases in volume 
appear earlier in the survey and may be correlated with the switch to the N2 
generator and a documented generator outlet pressure adjustment, but this is not 
the case with system II where dismounting and cleaning of the pipette late in 
the survey may have had the greatest effect.


TABLE 3: A summary of the mean analytical parameters and mean analytical 
         differences for the three batches of CRM analyzed on SOMMA-coulometer 
         systems I and II during the Indian Ocean Survey 1994-1996
_____________________________________________________________________________

 Leg       Slope     Int     Cal-    CRM   Precision,  Analytical difference
           (ec)      (ec)   factor  batch  n(±µmol/kg    const-vp/corr-vp
 -------   ------  -------  ------  -----  ----------  ---------------------
 System I 
 I8SI9S    1.0002   0.0008  1.0043   23     1.15(54)        -0.41/-0.41 
 I9N       1.0007   0.0013  1.0045   23     0.86(71)        -0.83/-0.20 

 I8NI5E    1.0007   0.0013  1.0062   23     1.36(55)        -1.71/-0.15 
 I3        1.0007   0.0013  1.0053   23     0.98(37)        -2.33/-1.31 
 I3        1.0007   0.0013  1.0053   26     0.98(20)        -2.77/-1.72 

 I5WI4     0.9998  -0.0057  1.0041   26     1.31(41)        -1.83/-0.88 
 I7N       0.9998  -0.0057  1.0043   23     1.71(6)         -1.66/-0.69 
 I7N       0.9998  -0.0057  1.0043   26     1.88(55)        -1.74/-0.78 
 I7N       0.9998  -0.0057  1.0043   27     0.88(8)         -2.91/-1.95 
 I1        0.9998  -0.0057  1.0038   27     1.10(64)        -2.82/-1.45 

 I10       0.9998  -0.0057  1.0037   27     0.72(32)        -0.58/-0.58 
 I2        0.9998  -0.0057  1.0040   27     1.11(27)        -0.57/-0.77 
 Mean                       1.0045          1.17(470)       -1.68/-0.91 
 S.D.(±)                    0.0008          0.35             0.92/ 0.58 

 System II 
 1I8SI9S   0.9996  -0.0025  1.0041   23     1.18(104)       -0.89/-0.89 
 I9N       0.9996  -0.0025  1.0039   23     0.90(70)        -1.83/-1.57 

 I8NI5E    0.9996  -0.0025  1.0041   23     1.14(59)        -1.73/-0.35 
 I3        0.9996  -0.0025  1.0045   23     0.85(35)        -2.14/-0.62 
 I3        0.9996  -0.0025  1.0045   26     0.69(13)        -2.44/-1.11 
 
 I5WI4     0.9998   0.0045  1.0050   26     0.79(41)        -2.14/-1.28 
 I7N       0.9998   0.0045  1.0051   23     0.88(5 )        -3.25/-1.47 
 I7N       0.9998   0.0045  1.0051   26     0.84(54)        -2.09/-0.32 
 I7N       0.9998   0.0045  1.0051   27     0.77(10)        -2.88/-1.10 
 I1        0.9998   0.0045  1.0041   27     1.11(70)        -3.51/-1.38 
 
 I10       0.9998   0.0045  1.0038   27     0.65(28)        -0.66/-0.66 
 I2        0.9998   0.0045  1.0035   27     1.11(24)        -1.38/-1.39 
 Mean                       1.0042          0.91(513)       -2.08/-1.01 
 S.D.(±)                    0.0005          0.18             0.87/ 0.44 
_____________________________________________________________________________
 For each CRM batch analyze d, precision is given as the standard deviation of 
 the mean of (n) analyses. Abbreviations: ec, electronic calibration; calfactor, 
 gas calibration factor; Int, intercept; const-vp, mean analytical difference 
 calculated using a constant pipette volume; corr-vp, mean analytical difference 
 calculated using the leg-specific V(cal) (Table 2). 
  (a) Gas Generator introduced as CG source. 
  (b) Gas generator output pressure adjusted from 5 to 10 psi. 
  (c) Pipette dismounted, cleaned and recalibrated.


3.2. CRM ANALYSES AND SYSTEM ACCURACY

In addition to the leg-specific pipette volumes, Fig. 4a (system I) and Fig. 4b 
(system II) show the mean analytical differences (analyzed TCO2-certified TCO2) 
and the mean gas calibration factors for each survey leg. The plots are scaled 
so that each Y-axis spans a similar range in order that the factors controlling 
system accuracy can be more readily identified. These data are also tabulated 
and summarized in Table 3. Table 3 shows that the gravimetric volume 
determinations (Table 2) have detected real changes in V(cal) during the survey. 
The mean analytical differences calculated with the corrected pipette volumes 
(corr-vp, Table 3) are -0.91 and -1.01 µmol/kg for systems I and II, 
respectively. If the pipette volumes determined at the beginning of the survey 
(const-vp) were used, the corresponding differences would be -1.61 and -2.08 
µmol/kg, showing that the routine determination of pipette volume increased 
accuracy by a factor of ~2.

Fig. 5 is a bar chart of the mean analytical difference (accuracy) for systems I 
and II as a function of cell carbon age. Both systems behave very similarly with 
the best precision and accuracy early in the cell lifetime (<10 mg C), 
increasing differences for cells of intermediate ages (>10 to <30 mg C), and 
smaller differences for carbon ages exceeding 30 mg C which are not 
significantly different from those at ages <10 mg C. No corrections based on the 
analyzed-certified TCO2 differences or cell age have been applied to the CDIAC 
data set.


Fig. 5.  A plot showing the distribution of mean analytical differences for CRM 
         analyses vs. coulometer cell age for SOMMA-coulometer systems I (open 
         bars) and II (filled bars) during the Indian Ocean Survey 1994-1996. 
         The error bars represent the 95% confidence interval for the mean 
         differences, and the numbers inside the columns are the number of 
         measurements (n) used to compute the means.


3.3. SYSTEM REPEATABILITY AND PRECISION DURING THE SURVEY

For the survey as a whole, the operating conditions and analytical performance 
of the two SOMMA systems were virtually identical. Survey-wide the mean gas 
calibration factors of the two systems were nearly identical (1.0045 for system 
I compared to 1.0042 for II). While both systems yielded slightly negative (~1.0 
µmol/kg) mean analytical differences (Table 3), the standard deviation of the 
analytical differences was slightly better on system II (±0.91 µmol/kg) than 
system I (1.17 µmol/kg). This is consistent with the gravimetric volume 
determinations where system II also exhibited a slightly higher precision 
(sp^2=±0.0036 cm^3 vs. ±0.0049 cm^3 for system I).

For the CRM analyses, the precision or pooled standard deviation (sp^2) 
calculated according to Youden (1951) is 1.19 µmol/kg (df=977). For this 
calculation, the three batches of CRM analyzed on the two systems are treated as 
six separate samples with multiple replicates. Because sp^2 includes CRM data 
measured on both systems on all legs, it applies to both systems on all legs. 
For water samples, sp^2 was calculated from duplicates analyzed on each system 
during leg I8SI9S at the start of the survey and leg I5WI4 about half way 
through the survey. The sp^2 for leg I8SI9S is ±1.26 µmol/kg (df=15), and for 
leg I5WI4, sp^2 is ±0.91 µmol/kg (df=21). These values are consistent with the 
precision of the CRM analyses given in Table 3. For the survey, the overall 
precision of the TCO2 determination is ±1.19 µmol/kg.

Fig. 6 is a plot of the analytical differences by system and CRM batch for the 
entire survey. The differences, calculated using the parameters in Table 3, 
reiterate the point that there are no significant analytical differences (bias) 
between systems or between CRM batches.


Fig. 6.  The analytical differences for the CRM analyses made on SOMMA-
         coulometer systems I and II during the Indian Ocean Survey 1994-1996 
         with separate symbols for the results from the two systems and for the 
         three batches of CRM analyzed. The beginning and end of each leg is 
         marked by vertical dashed lines. The respective salinities and 
         certified TCO2 (µmol/kg) for batches 23, 26, and 27 are 33.483 and 
         1993.10, 33.258 and 1978.34, 33.209 and 1988.10 µmol/kg.



4. DISCUSSION

The Indian Ocean CO2 Survey differed from the previous DOE CO2 Survey efforts in 
that a single ship was used for all legs, and that the measurement groups shared 
the same analytical equipment. The latter included the use of a single cache of 
coulometric reagents (two different lot numbers both of which were tested pre-
cruise with CRM), invariant sources of analytical gases, use of the same 
titration cell assemblies, standard sampling procedures, and standardized 
software. There was a pre-cruise training session, and all of the participants 
had prior experience with the sampling and measurement techniques (poisoning, 
reagent concentrations, standard calculations, glassware calibration, etc.) 
documented in the DOE Handbook of Methods (DOE, 1994). Thus, an extraordinary 
effort over several years to ensure analytical quality and uniformity culminated 
in the procedures used during the Indian Ocean Survey.

An improvement in system accuracy (Table 3) of approximately 1 part in 2000 
shows that the effort to gravimetrically determine the pipette volumes on each 
leg was worthwhile. The volumes of both systems did decrease slightly but 
significantly with time. Possible explanations include pressure changes in the 
carrier gas source (system I) or fouling of the glass pipette walls causing 
altered surface tension or displacement of small amounts of liquid (system II). 
Because the samples were poisoned with HgCl(2), it is unlikely that biological 
fouling was a problem, but the high quantity of grease used to seal the CRM 
bottles makes it possible that some of this grease found its way into the 
pipettes. After cleaning, V(cal) for leg I10 remained unchanged compared to the 
preceding leg I1 on system I and increased slightly on system II, but for both 
systems it was significantly smaller than the V(cal) determined for the initial 
leg (I8SI9S). After cleaning, the mean analytical difference for leg I10 (system 
I and II, n=2) was -0.62 µmol/kg compared to -0.40 µmol/kg on the initial leg 
I8S when the instruments were fresh from the laboratory indicating that pipettes 
were most accurate after cleaning. Whatever the cause of subsequent volume 
changes, the data confirm the importance of periodically redetermining the 
volume, and indicate that the procedure is mandatory for the highest accuracy 
over extended periods of analytical work and/or after major changes in system 
plumbing. In aggregate, both systems share a small negative analytical 
difference (-1.0 µmol/kg) for the CRM analyses throughout the survey even after 
pipette volume corrections have been applied.

The cell accuracy vs. carbon age relationship shown in Fig. 5 is typical of data 
from previous cruises (K.M. Johnson, unpublished data). The best precision and 
accuracy is found at a carbon age of 5-10 mg C, a slightly reduced accuracy 
(usually as lower recoveries of CRM carbon) is observed between 10-30 mg C, 
gradually increasing recoveries and imprecision after 30 mg C until cell death 
where cell death is defined as a positive difference ≥3.0 µmol/kg. This behavior 
underlies the recommendation that cell lifetimes be limited to a carbon age of 
≤35 mg C, i.e., to limit imprecision and because cell death normally occurs at 
carbon ages ≥35 mg C. During the survey, neither CRM or samples were run until 
the carbon age exceeded 5 mg C. This was accomplished by configuring the 
software to automatically run a test sample and three consecutive gas 
calibrations before samples were analyzed. The reasons for the observed cell 
behavior are not understood, but limiting cell lifetimes from ≥5 to ≤35 mg C 
probably helps to limit system drift which might compromise the sample analyses. 
Although the imprecision associated with cell aging is small and cell failure is 
rare at carbon ages ≤35 mg C, good analytical practice requires that samples 
should be run in random order rather than systematically in order of depth to 
avoid systematic biases which might result from any drift associated with cell 
age.

Fig. 4a and b shows no correlation between the gas calibration factors and the 
analytical differences after the CRM analyses were corrected for pipette volume 
changes (Table 3). These data do show that the overall mean gas calibration 
factor for both systems is nearly the same (1.004), but that the temporal record 
with respect to gas calibration factor variation is not. Calibration factor 
variation (R.S.D.=0.06-0.08%) is greater than the variation in V(cal) 
(R.S.D.=0.03%), and is therefore a potentially more important control on system 
accuracy. For system I, the highest mean gas calibration factor (poorest 
recovery of CO2) was observed on leg I8N, while for system II, the corresponding 
result occurred months later, on leg I7N (same measurement group, see Table 1). 
Because the system calibration factors are not correlated with the analytical 
differences, the observed variations in calibration factors are real, i.e., they 
document a change in system response shared by the calibration and sample 
analyses rather than an isolated malfunction of the gas calibration hardware 
(see Fig. 2).

The reason for gas calibration factor variation is not known. It could 
conceivably be due to procedures unique to each measurement group, e.g., 
positioning of the cathode electrode and the gas inlet tube with respect to the 
coulometer light source and photodetector (Fig. 3), plumbing differences 
resulting in leaks and small losses of CO2, or the amount of reagents used to 
dry the gas stream (Fig. 2). These procedural differences would affect sample 
determinations and gas calibration results similarly because, as Fig. 2 shows, 
the calibration gas follows the same route to the coulometer as the CO2 
extracted from samples. Table 3 suggests at least one other possible cause of 
gas calibration factor variation. The coulometers were electronically calibrated 
by the BNL group at the start of the survey (I8SI9S) and about half way through 
the survey on leg I5WI4. Between legs I8SI9S and I5WI4 the coulometer 
calibration appears to have changed by 0.08% for system I, and by 0.02% for 
system II. These calibrations were separated by many weeks so the exact 
magnitude or timing of the shift is not known. Changes in the coulometer's 
circuitry affecting the electronic slope (Slope(ec)) and intercept (Int(ec)) 
would alter the gas calibration factor but would not affect system accuracy 
because, until recalibration, the previous electronic calibration coefficients 
represent constants in Eq. 1. In both systems, the sense of the apparent change 
in electronic calibration coefficients compared to the earlier coefficients is 
qualitatively consistent with the observed short-lived variation in gas 
calibration factors, and it is possible that this variation was due to 
unexplained changes in the coulometer response.

The important point is the efficacy of the gas calibration procedure: 
corrections to data based solely on the CRM analyses which would usually be 
applied on a cruise-average basis may mask short term variation or step changes 
in system response arising from stochastic or procedural changes. The gas 
calibration procedure, in which known masses of pure CO2 are regularly analyzed, 
is an independent check of all system components except pipette volume, and it 
provides traceable documentation for the subsequent survey results.

The importance of cell assembly selection should be stressed. Investigators have 
found that the behavior of individual cell assemblies can vary significantly 
(e.g., D. Chipman, personal communication, July 1996). The factors affecting 
cell performance are still not yet completely understood. Hence, the use of 
empirical selection criteria such as those given in Section 2 is recommended. It 
is beyond the scope of the paper to go into detail, but point 'a' in Fig. 3 
illustrates one of the locations for potential problems. A faulty seal where the 
platinum electrode emerges from the glass insulator could allow infiltration and 
trapping of the cell solution in the insulator where electrochemical or chemical 
reactions could take place. Small quantities of this solution (at a pH different 
from the bulk cell solution) could randomly exchange with the bulk cell solution 
and cause titration errors. This would be difficult to detect. Assemblies which 
did not meet the empirical performance criteria in Section 2 were simply not 
used. The attention to cell assembly testing and selection is believed to a 
major reason for the success of the Indian Ocean TCO2 Survey. The survey 
assemblies were also carefully washed and dried. Drying at 55±5°C removes 
traces of the volatile and reactive cell solution from the rubber caps.


TABLE 4: Results of the crossover analysis (see text for details)
         __________________________________________________________________
         
          Crossover  Expedition legs       Stations        TCO2 difference
          no.        Late      Early   Late       Early    ±S.D.(µmol/kg) 
          ---------  ----------------  ------------------  ---------------
              1      I1        I7N     927:931    780:784     -2.5±0.5 
              2      I1        I9N     987:990    266:270     -2.7±6.3(a) 
              3      I1        I9N     996:998    233:235     -0.9±1.7 
              4      I2        I7N     1205       728:730     -0.4±1.1 
              5      I2        I8NI5E  1137:1139  320:324      1.5±1.5 
              6      I2        I9N     1094:1096  191:193     -3.0±0.7 
              7      I2        I10     1078       1075        -1.5±1.5 
              8      I5WI4     I3      705        547:549      1.6±0.5 
              9      I3        I8NI5E  498:501    346:348     -2.6±0.7 
             10      I3        I9N     472        169          1.1±1.2 
             11      I10       I3      1039       452:454      1.1±0.3 
             12      I8NI5E    I8SI9S  404:408    9:13        -1.1±1.0 
             13      I1        I7N     861        808          1.3±0.4(b) 
            Mean                                              -0.78 
         __________________________________________________________________
          The TCO difference between legs is calculated by subtracting data 
          from the earlier sampling of a crossover location from that of the 
          later sampling. The station numbers refer to the actual stations 
          used for this analysis. 
           (a) The LOESS fit diverged significantly from the data. 
           (b) Not considered reliable due to insufficient data.
         


5. CROSSOVER ANALYSIS

The agreement between TCO2 measurements made at similar locations, but on 
different legs of the survey, were used as a check on the internal consistency 
of the measurements. Deep measurements were used because of the lower variabil-
ity in TCO2 observed in the deep ocean. Because most motion in the ocean 
interior takes place along surfaces of constant density (isopycnals), 
comparisons were made along isopycnal surfaces rather than depth.

Our crossover analysis was performed as follows:

(1) Locations at which different cruise legs intersected were identified as 
    'crossover points.' These are identified in Table 4 and are plotted on Fig. 1.

(2) Stations located in the immediate proximity of these crossover points, for 
    which TCO2 data existed, were selected for the comparison. In general, 
    stations located within 100 km of the crossover location were selected.

(3) For water samples collected below 2500 m, smooth curves were fit through the 
    TCO2 data as a function of the density anomaly referenced to 3000 dbar 
    (sigma 3) using Cleveland's LOESS smoother (Cleveland and Devlin, 1988). A 
    separate fit was performed to the data collected from each of the two 
    intersecting legs. The tension parameter for the smoother was adjusted 
    subjectively to give a 'reasonable' fit to the data at the majority of the 
    crossover locations, and the same value for the tension parameter was used 
    for all of the crossovers. Hence, while the fits to the data may not 
    necessarily represent the best possible at each individual crossover point, 
    the smoothing function has been consistently applied to all crossovers.

(4) For each crossover, the difference between the two smooth curves was 
    evaluated at 50 evenly spaced intervals which covered the density range over 
    which the two data sets overlapped. A mean and a standard deviation of the 
    difference between the two curves was estimated based on these 50 values, 
    and these values are reported in Table 4. An illustration of a typical 
    analysis, the fitted data for crossover 4, is plotted on Fig. 7.


Fig. 7.  An example of a crossover analysis using the TCO2 vs. density fits at 
         crossover location #4. This location was first sampled on leg I7N in 
         July 1995. It was resampled during January 1996 on leg I2. The TCO2 
         data from stations within 100 km of the crossover location and 
         depths>2500 m have been plotted vs. the potential density anomaly 
         referenced to 3000 dbar (sigma 3). The solid curves represent fits to 
         the data using a LOESS smoother (see text). The difference between the 
         fits for the two separate legs was evaluated at 50 density intervals 
         spaced evenly within the overlapping density range of the two legs (see 
         Table 4). The legend shows the station numbers used for the comparison.


The results of the crossover analysis indicate that absolute leg-to-leg 
differences are always <3.0 µmol/kg (Table 4). Note that the comparisons were 
evaluated consistently such that the fit to data from the earlier leg at each 
crossover was subtracted from the fit to the later leg's data. Any uncorrected, 
long-term, monotonic drift in the calibration of the SOMMA analyzers over the 
course of the Indian Ocean expedition would therefore result in a non-zero value 
for the overall mean of these differences. The overall mean and standard 
deviation of the differences at crossovers 1-12 is -0.78 (±1.74) µmol/kg, and 
there was also no significant correlation between the individual differences 
derived from each crossover and the number of days which separated the crossover 
samplings. In general, the results of the crossover analysis are quite 
consistent with the overall precision (±1.2 µmol/kg) of the CRM analyses (see 
Section 3.3), and confirms that this precision applies to both systems 
throughout the survey. There is no suggestion in the crossover results of any 
additional significant sources of error or uncertainty.



6. CONCLUSIONS

In summary, personnel aboard the R/V Knorr have been able to use the SOMMA-
coulometer system to consistently replicate within analytical error the 
certified CRM TCO2 values. They have been able to use these systems to make, 
counting duplicates and CRM, over 20,000 determinations of TCO2 during the 14 
months of the Indian Ocean Survey without significant instrument down time. The 
measurement groups have accomplished the following.

(1) They have charted the history of the to-deliver volume of the sample 
    pipettes by gravimetric determinations, and corrected the water sample data 
    for the documented changes in the pipette volumes. The change in system 
    response due to the change in pipette volume corresponded to approximately 1 
    part in 2000 for TCO2 on both systems over the 10 months prior to recleaning 
    of the pipettes.

(2) The groups have determined that the survey precision for the TCO2 analyses, 
    irrespective of which leg or system the water samples were analyzed on, was 
    ±1.2 µmol/kg. The precision of the two instruments was nearly identical and 
    consistent throughout the 14 months of the survey.

(3) They have analyzed nearly 1000 CRM with an overall difference between the 
    analyzed and certified TCO2 of -1.0 µmol/kg (0.05%) on both systems which 
    demonstrates the equivalency of the two independent instruments, and meets 
    the survey's goal for accuracy.

(4) The measurement groups have documented the influence of factors besides 
    pipette volume which could have affected accuracy including electronic 
    calibration, gas calibration, cell age, and cell assembly selection.

For precision, the pooled standard deviation (sp^2=1.2 µmol/kg), calculated 
according to Youden (1951), is the most conservative estimate of precision 
because it includes all random analytical errors (sampling, instrumental, and 
method). The identical accuracy for the CRM analyses on both systems and the 
results of the crossover analysis (Table 4) indicate that the sp^2 statistic can 
be used to evaluate survey data sets irrespective of the leg or system the data 
originated from.

The SOMMA-coulometry systems have allowed several scientific groups in a shared 
effort to examine carbon inventories and aquatic carbon cycling. For the Indian 
Ocean Survey, the sensitivity of the TCO2 determinations defined as the ratio of 
their precision (1.2 µmol/kg) over the TCO2 dynamic range (250 µmol/kg) was 0.4% 
which approaches the 0.1% sensitivity of the salinometers used, and these 
systems were as reliable as the salinometers. If their reliability is to be 
improved, the focus should be on understanding the basic behavior of the cell 
assemblies and the chemical behavior of the cell solutions as they age, so that 
procedural corrections can be made. The accuracy and precision of the Indian 
Ocean TCO2 analyses indicates that these data will be more than adequate for 
testing applicable oceanographic models, and allow the direct measurement of the 
CO2 uptake if and when these lines are resampled.



ACKNOWLEDGEMENTS

We would like to thank the US Department of Energy's Office of Biological and 
Environmental Research for their support. The success of the Indian Ocean CO2 
Survey was due to the shared efforts of the DOE Science Team. We thank John 
Downing for his initial organization of the Science Team and assistance in 
getting the US CO2 Survey underway. We thank the chief scientists, scientific 
staff, and crew aboard the R/V Knorr for their assistance throughout. Dave 
Chipman and Taro Takahashi are acknowledged for helpful comments and advice. The 
instruments used for the survey were produced at the Equipment Development 
Laboratory (EDL) at the University of Rhode Island's Graduate School of 
Oceanography under the supervision of Dr. John King and David Butler. This 
research was performed under the auspices of the United States Department of 
Energy under Contract No. DE-AC02-98CH10886.



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DOE, 1994. Handbook of methods for the analysis of the various parameters of the 
    carbon dioxide system in sea water; version 2.0. ORNL/CDIAC-74.

Huffman Jr., E.W.D., 1977. Performance of a new automatic carbon dioxide 
    coulometer. Microchem. J. 22, pp. 567-573 

Johnson, K.M., 1995. Operator's Manual. Single-Operator Multiparameter Metabolic 
    Analyzer (SOMMA) for Total Carbon Dioxide (CT) with Coulometric Detection. 
    Version 3.0. Available from K.M. Johnson, Department of Applied Science, 
    Brookhaven National Laboratory, Upton, NY.

Johnson, K.M., Wallace, D.W.R., 1992. The single-operator multiparameter 
    metabolic analyzer for total carbon dioxide with coulometric detection. DOE 
    research summary no. 19. Carbon Dioxide Information Analysis Center, Oak 
    Ridge National Laboratory, TN.

Johnson, K.M., King, A.E. and Sieburth, J.McN., 1985. Coulometric TCO2 analyses 
    for marine studies: an introduction. Mar. Chem. 16, pp. 61-82 

Johnson, K.M., Sieburth, J.McN., Williams, P.J.leB. and Bränström, L., 1987. 
    Coulometric TCO2 analysis for marine studies: automation and calibration. 
    Mar. Chem. 21, pp. 117-133 

Johnson, K.M., Wills, K.D., Butler, D.B., Johnson, W.K. and Wong, C.S., 1993. 
    Coulometric total carbon dioxide analysis for marine studies: maximizing the 
    performance of an automated gas extraction system and coulometric detector. 
    Mar. Chem. 44, pp. 167-187 

Millero, F.J. and Poisson, A., 1981. International one-atmosphere equation of 
    state for sea water. Deep-Sea Res. 28, pp. 625-629 

Millero, F.J., Dickson, A.G., Eischeid, G., Goyet, C., Guenther, P., Johnson, 
    K.M., Lee, K., Purkerson, D., Sabine, C.L., Key, R., Schottle, R.G., 
    Wallace, D.W.R., Lewis, E.R. and Winn, C.D., 1998. Assessment of the quality 
    of the shipboard measurements of total alkalinity on the WOCE Hydrographic 
    Program Indian Ocean CO2 survey cruises 1994-1996. Mar. Chem. 63, pp. 9-20 

Sabine, C.L., Key, R.M., 1998. Surface water and atmospheric underway carbon 
    data obtained during the world ocean circulation experiment Indian Ocean 
    survey cruises (R/V Knorr, December 1994-January 1996). NDP-064, Carbon 
    Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak 
    Ridge, TN.

Taylor, J.K., 1990. Statistical techniques for data analysis. Lewis Publishers, 
    Chelsea, 200 pp.

Wilke, R.J., Wallace, D.W.R. and Johnson, K.M., 1993. A water-based, gravimetric 
    method for the determination of gas sample loop volume. Anal. Chem. 65, pp. 
    2403-2406 

Youden, W.J., 1951. Statistical Methods for Chemists. Wiley, New York, 126 pp.










                                  APPENDIX C:

                        REPRINT OF PERTINENT LITERATURE




Millero F.J., A.G. Dickson, G. Eischeid, C. Goyet, P. Guenther, K.M. Johnson, 
R.M. Key, K. Lee, D. Purkerson, C.L. Sabine, R.G. Schottle, D.W. .R. Wallace, E. 
Lewis and C.D. Winn, Assessment of the quality of the shipboard measurements of 
total alkalinity on the WOCE Hydrographic Program Indian Ocean CO2 survey 
cruises 1994-1996, Marine Chemistry 63:9-20.





Marine Chemistry 
63 1998 9 - 20


   ASSESSMENT OF THE QUALITY OF THE SHIPBOARD MEASUREMENTS OF TOTAL ALKALINITY
   ON THE WOCE HYDROGRAPHIC PROGRAM INDIAN OCEAN CO2 SURVEY CRUISES 1994-1996


        Frank J. Millero(a,*), Andrew G. Dickson(b), Greg Eischeid(c),
 Catherine Goyet(c), Peter Guenther(b), Kenneth M. Johnson(d), Robert M. Key(e),
Kitack Lee(f), Dave Purkerson(a), Christopher L. Sabine(e), Rolf G. Schottle(g), 
      Douglas W. R. Wallace(d), Ernie Lewis(d) and Christopher D. Winn(g) 

 (a) Rosenstiel School of Marine and Atmospheric Science, University of Miami, 
     Miami, FL 33149, USA
 (b) Scripps Institution of Oceanography, University of California, 
     La Jolla, San Diego, CA 92093, USA
 (c) Woods Hole Oceanographic Institute, Woods Hole, MA 02543, USA
 (d) Department of Applied Science, Brookhaven National Laboratory, 
     Upton, NY 111973, USA
 (e) Department of Geosciences, Princeton University, Princeton, NJ 08544, USA
 (f) NOAA/AOML, Miami, FL 33149, USA
 (g) Department of Oceanography, University of Hawaii, Honolulu, HI 96822, USA 

     *Corresponding author.

Received 16 January 1998; revised 31 March 1998; accepted 7 April 1998. 
Available online 8 December 1998. 





ABSTRACT

In 1995, we participated in a number of WOCE Hydrographic Program cruises in 
the Indian Ocean as part of the Joint Global Ocean Flux Study (JGOFS) CO2 
Survey sponsored by the Department of Energy (DOE). Two titration systems 
were used throughout this study to determine the pH, total alkalinity (TA) 
and total inorganic carbon dioxide (TCO2) of the samples collected during 
these cruises. The performance of these systems was monitored by making 
closed cell titration measurements on Certified Reference Materials (CRMs). A 
total of 962 titrations were made on six batches of CRMs during the cruises. 
The reproducibility calculated from these titrations was ±0.007 in pH, ±4.2 
µmol/kg-1 in TA, and ±4.1 µmol/kg-1 in TCO2. The at-sea measurements on the 
CRMs were in reasonable agreement with laboratory measurements made on the 
same batches. These results demonstrate that the CRMs can be used as a 
reference standard for TA and to monitor the performance of titration systems 
at sea. Measurements made on the various legs of the cruise agreed to within 
6 µmol/kg-1 at the 15 crossover points. The overall mean and standard 
deviation of the differences at all the crossovers are 2.1±2.1 µmol/kg-1. 
These crossover results are quite consistent with the overall reproducibility 
of the CRM analyses for TA (±4 µmol/kg-1) over the duration of the entire 
survey. The TA results for the Indian Ocean cruises provide a reliable data 
set that when combined with TCO2 data can completely characterize the 
carbonate system.



Author Keywords: alkalinity; WOCE Hydrographic Program; CO2
Index Terms:     reproductive toxicity; boron

0304-4203r98r$ - see front matter q 1998 Elsevier Science B.V. All rights 
reserved. 

PII: S0304-42039800043-7







ARTICLE OUTLINE

1. Introduction
2. Methods
2.1. Titration system
2.1.1. Electrodes
2.1.2. Standard acids
2.1.3. Volume of the cells
2.1.4. Volume of titrant
2.2. Evaluation of the carbonate parameters
3. Results and discussion
3.1. Laboratory ta measurements of CRMs
3.2. At sea measurements of TA, TCO2, and pH on CRMs
3.2.1. Accuracy of at sea measurements
3.2.2. Long term stability of a cell performance
3.3. Crossover analysis
4. Conclusion
Acknowledgements
References







1. INTRODUCTION

From 1994 to 1996, a number of cruises were made in the Indian Ocean as part 
of the World Ocean Circulation Experiment (WOCE) Hydrographic Program to 
characterize the carbon dioxide system. This survey of CO2 was an integral 
part of the Joint Global Ocean Flux Study (JGOFS). The goals of this survey 
were to: (1) Quantify the uptake of anthropogenic carbon dioxide by the 
oceans to better predict future atmospheric carbon dioxide levels; (2) 
Provide a global description of the carbon dioxide in the oceans to aid in 
the development of a 3-dimensional model of the oceanic carbon cycle; and (3) 
Characterize the transport of CO2 across the air-sea interface and the large 
scale transports of carbon dioxide within the oceans.

To satisfy these goals, it was necessary to make very precise measurements of 
at least two of the carbonate system parameters (pH; total alkalinity, TA; 
total carbon dioxide, TCO2; and the fugacity of carbon dioxide, fCO2). Within 
the United States a large part of this survey was conducted by a team of 
investigators supported by the US Department of Energy. The team selected the 
measurement of TCO2 (Johnson et al., 1998) and of TA as the parameters to be 
measured in the water column and fCO2 in the atmosphere and surface waters. 
To insure that the measurements of TCO2 and TA were as precise and accurate 
as possible Certified Reference Materials (CRMs) (Dickson, 1990a) were used 
throughout the studies. The team also developed a set of Standard Operating 
Procedures1 (DOE, 1994) and, to a large extent, shared a common approach to 
the measurement program.

For the studies in the Indian Ocean, the team shared equipment throughout the 
study. This paper presents the results of this team effort to precisely and 
accurately determine the total alkalinity during these cruises and the 
intercomparison between cruises. A companion paper (Johnson et al., 1998) 
describes the total carbon dioxide measurements.



(1) DOE, 1991. Handbook of methods for the analysis of the various parameters of 
    the carbon dioxide system in sea water, In: Dickson, A.G., Goyet, C. (Eds.), 
    Version 1.0, Unpublished manuscript



2. METHODS

The total alkalinity was determined on the JGOFS Indian Ocean cruises by the 
DOE group using systems described in detail by Millero et al. (1993). The 
total alkalinity of seawater was evaluated from the proton balance at the 
alkalinity equivalence point, pHequiv4.5, according to the exact definition mmmm
of total alkalinity (Dickson, 1981)


                     TA = [HCO¯(3)]+2[CO(3)(^2¯)]+[B(OH)¯(4)]
                         +[OH¯]+[HPO^2¯(4)]+2[PO^3¯(4)]
                          +[SiO(OH)¯(3)]+[HS¯]+[NH(3)]
                        -[H+]-[HSO¯(4)]-[HF]-[H(3)PO(4)]                   (1)


At any point in the titration, the total alkalinity of seawater can be 
calculated from the equation


                  (W(0) x TA-W x C(HCl))/(W(0)+W) = [HCO¯(3)]
                         +2[CO^2¯(3)]+[B(OH)¯(4)]+[OH¯]
                      +[HPO^2¯(4)]+2PO^3¯(4)]+SiO(OH)¯(3)]
                               +[HS¯]+[NH(3)]-[H+]
                           -[HSO¯(4)]-[HF]-[H(3)PO(4)]                     (2)



where W0 is the mass of the sample to be titrated, CHCl is the concentration 
of acid titrant, and W is the mass of acid added. In the calculations, 
volumes of the sample and of the acid were converted to mass using the 
density of seawater (Millero and Poisson, 1981) and the density of HCl in 
NaCl (Millero et al., 1977). Direct measurements made on the density of the 
acid used agreed to within 10 ppm with the equations used in the computer 
code. At the endpoint (W2) the total alkalinity is given by


                              TA = W2 x C(HCl)/W(0)                        (3)


The uncertainties in TA associated with acid concentration (0.25±0.0001 M), 
mass of acid delivered (2.5±0.0005 g), and mass of the sample (200±0.05 g) 
are ±1, ±0.5, and ±0.5 µmol/kg-1, respectively (which gives a probable error 
of about ±1 µmol/kg-1). By using the same acid, titrators, and acid 
throughout a given cruise one can obtain a precision that is comparable with 
this probable error. Discussed below are more details on the components of 
the titration systems.


2.1. TITRATION SYSTEM

The titration systems used to determine TA consist of a Metrohm 665 Dosimat 
titrator and an Orion 720A pH meter controlled by a personal computer 
(Millero et al., 1993). Both the acid titrant in a water-jacketed burette and 
the seawater sample in a water-jacketed cell were controlled to a constant 
temperature of 25±0.1°C with a Neslab constant temperature bath. The 
plexiglass water-jacketed cells used for our studies were similar to that 
used by Bradshaw and Brewer (1988) except a larger volume (about 200 cm3) was 
used to improve the precision. These cells have fill and drain valves that 
increased the reproducibility of the cell volume.

A Lab Windows C program is used to run the titration and record the volume of 
the added acid and the emf of the electrodes using RS232 interfaces. The 
titration is made by adding HCl to seawater past the alkalinity end point. A 
typical titration records the average of ten emf readings after they become 
stable (±0.09 mV) and adds enough acid to change the voltage by a pre-
assigned increment (13 mV). In contrast to the delivery of a fixed volume of 
acid, this method gives more data points in the range of a rapid increase in 
the emf near the endpoint. A full titration (25 points) takes about 20 min.


2.1.1. ELECTRODES

The electrodes used to measure the emf of the sample during a titration 
consist of a ROSS glass pH electrode and an Orion double junction Ag, AgCl 
reference electrode. A number of electrodes were screened to select those to 
be used in the titrators. Electrodes with non-Nernstian behavior (slopes more 
than 1.0 mV different from the theoretical value) were discarded. The 
reliability of the electrodes was evaluated by determining the TA, TCO2 and 
pH of Gulf Stream seawater. The titration values of TCO2 are normally higher 
than the values measured by coulometry and the values of pH are typically 
lower than the values obtained by spectrophotometric methods. These 
differences in TCO2 and pH are caused by the non-Nernstian behavior of the 
electrodes (Millero et al., 1993). We selected electrodes which gave values 
of TCO2 and pH close to the values determined by coulometric and by 
spectrophotometric methods, respectively.


2.1.2. STANDARD ACIDS

The HCl used for this study and for all of our cruises was made in the 
laboratory, standardized, and stored in 500 cm3 glass bottles. The 0.25 M HCl 
solutions were made from 1 M Mallinckrodt standard solutions in 0.45 M NaCl 
to yield an ionic strength equivalent to that of average seawater (0.7 M). 
The concentration of HCl was measured using a constant current coulometric 
technique (Taylor and Smith, 1959; Marinenko and Taylor, 1968). Coulometric 
analysis of the acids used for these cruises agreed to ±0.0001 M with the 
analyses performed independently on the same batches of acids in Dr. A. 
Dickson's laboratory at Scripps Institution of Oceanography (SIO). The mutual 
consistency of these acids was also confirmed by comparing the values of TA 
measured on Gulf Stream seawater using different batches of acids, but using 
the same titrator and electrodes. The uncertainties in TA associated with 
acid concentration (±0.0001 M) is 1 µmol/kg-1.


2.1.3. VOLUME OF THE CELLS

The volume of each of the titration cells used at sea was determined by 
comparing the values of TA obtained for Gulf Stream seawater with open and 
closed cells in the laboratory. All of the open cell laboratory TA 
measurements were made with weighed amounts of seawater in a cell with a 
small head-space. If the volume is correct, the TA from the open and closed 
cells should be the same, provided that the same acid, titrator, and 
electrodes are used. At least 10 measurements were made on each cell yielding 
an average TA that agreed with the assigned value to better than 1 µmol/kg-1. 
If the volume of a titration cell needed to be adjusted during the cruise 
(because of broken electrodes, plungers etc.), the volumes were determined 
from the daily titrations on low-nutrient surface seawater (usually collected 
before the first station) and Certified Reference Materials (CRMs) provided 
by Dr. A. Dickson (SIO). Post-cruise calibrations of the cells were made by 
comparing the values of TA for the Gulf Stream seawater and CRM with open and 
closed cells. The nominal volumes of all the cells were about 200 cm3, and 
the values were determined to ±0.05 cm3. The uncertainty in TA associated 
with this uncertainty in the volume of the cells (±0.05 cm3) is 0.5 µmol/kg-1 
obtained for the weighed samples.


2.1.4. VOLUME OF TITRANT

The volume of HCl delivered to the cell is traditionally assumed to have 
small uncertainty (Dickson, 1981) and equated to the digital output of the 
titrator. Calibrations of all the burettes of the Dosimats used were made 
with Milli-Q water at 25°C. Since the cell volumes are calibrated using 
standard solutions, errors in the accuracy of volume delivery will be 
partially canceled and included in the value of cell volumes assigned. The 
calibration of all the Dosimats used at sea and in the laboratory indicated 
that the amount of acid delivered (for a typical calculation) was uncertain 
to ±0.0005 cm3. This uncertainty in the volume delivered leads to an error in 
the TA of ±0.5 µmol/kg-1. Nevertheless, corrections to the Dosimat reading 
were made in all of our laboratory TA measurements and calibrations to insure 
that the assigned value for a different batch of CRM and Gulf Stream water 
was not affected by the use of different Dosimats. These corrections were 
also made when calculating the volume of each cell.


2.2. EVALUATION OF THE CARBONATE PARAMETERS

A FORTRAN computer program has been developed to calculate the carbonate 
parameters (pH, E*, TA, TCO2, and pK(1)) in the seawater solutions. The program 
is patterned after those developed by Dickson (1981), Johansson and Wedborg 
(1982) and Dickson (1; DOE, 1994). The fitting is performed using the STEPIT 
routine (J.P. Chandler, Oklahoma State University, Stillwater, OK 74074). The 
STEPIT software package minimizes the sum of squares of residuals by 
adjusting the parameters E*, TA, TCO2 and pK(1) of carbonic acid. The computer 
program is based on Eq. 2 and assumes that nutrients such as phosphate, 
silicate and ammonia are negligible. This assumption is strictly valid only 
for surface waters. Neglecting the concentration of nutrients in the seawater 
sample does not affect the accuracy of TA, but must be considered when 
calculating the carbonate alkalinity (CA=[HCO¯(3)]+2 [CO^2¯(3)]) from TA.

The pH and pK of the acids used in the program are on the seawater scale, 
[H+]sw[H+]+[HSO¯(4)]+[HF] (Dickson, 1984). The dissociation constants used in 
the program were taken from Dickson and Millero (1987) for carbonic acid, 
from Dickson (1990b) for boric acid, from Dickson and Riley (1979) for HF, 
from Dickson (1990c) for HSO¯(4) and from Millero (1995) for water. The program 
requires as inputs the concentration of acid, volume of the cell, salinity, 
temperature, measured emfs (E) and volumes of HCl (V). To obtain a reliable 
TA from a full titration, at least 25 data points should be collected (9 data 
points between pH 3.0 to 4.5). The precision of the fit is less than 0.4 µmol/ 
kg_1 when pK(1) is allowed to vary and 1.5 µmol/kg-1 when pK(1) is fixed. Our 
titration program has been compared to the titration programs used by others 
(Johansson and Wedborg, 1982; Bradshaw and Brewer, 1988) and the values of TA 
agree to within ±1 µmol/kg-1.



3. RESULTS AND DISCUSSION


3.1. LABORATORY TA MEASUREMENTS OF CRMS

The laboratory TA measurements made on the CRMs used throughout this study 
are summarized in Table 1. The results obtained by both laboratories 
demonstrate that no systematic differences in TA are found. With the 
exception of Batch 29, the differences in the measurements of the CRMs 
between the two laboratories are less that 2 µmol/kg-1. Since the Miami 
measurements were made with the same acid as used at sea, one cannot 
attribute the differences in Batch 29 to differences in the concentration of 
the acids (calibrated at SIO). The Miami measurements were also made using 
the same acid for all the batches of CRM within a one-week period to ensure 
the internal consistency of its results. The measurements made on the acid 
concentration in Miami and SIO by a coulometric titration were in agreement 
to ±0.0001 M, which is equivalent to an error of ±1 µmol/kg-1 in TA.


TABLE 1: Comparison of the total alkalinity of Certified Reference Materials 
         _______________________________________________________________
         
          Batch   SIO    Miami   ∆(S-M)  Cruise 
          -----  ------  ------  ------  ------------------------------
            23   2212.7  2213.7   -1.0   I8S/I9S, I9N, I8N/I5E, I3, I7N 
            24   2215.5  2215.8   -0.3   I8R    
            26   2176.6  2175.1    1.5   I3, I5W/I4, I-7N 
            27   2214.9  2214.3    0.6   I7N, I1, I10, I2 
            29   2184.8  2182.3    2.5   I8R    
            30   2201.9  2200.5    1.4   I2
         _______________________________________________________________


3.2. AT SEA MEASUREMENTS OF TA, TCO2, AND PH ON CRMS

3.2.1. Accuracy of at sea measurements

The tracts of the cruise made during the Indian Ocean studies are shown in 
Fig. 1. A total of 962 titrations were made on six batches of the CRMs during 
the cruises (Table 2). A summary of the pH, TA and TCO2 measurements made on 
CRMs (Table 3) throughout the cruise is shown in Fig. 2, Fig. 3 and Fig. 4. 
The reproducibility on the six batches of the CRMs used was ±0.007 in pH, 
±4.2 µmol/kg-1 in TA, and ±4.1 µmol/kg-1 in TCO2. The at sea TA measurements 
on the CRMs were in good agreement (2-4 µmol/kg-1) with laboratory 
measurements made on the same batches at MIAMI and SIO. These small 
differences (2-4 µmol/kg-1) are well within the overall precision of our 
measurements and can be attributed to uncertainties in the volume of cells 
assigned in the laboratory before the cruises. However, the cells used on I7 
gave significantly greater errors than the values obtained in the 
laboratories on the same batch of CRM. These large discrepancies might be 
attributed to inaccurately assigned volumes of the cells after they were 
repaired for leakage due to repositioning of a reference electrode after 
changing the inner filling solution.


Fig. 1. Cruise tracts of the Indian Ocean Studies showing crossover points.


TABLE 2: Measurements of pH, TA and TCO2 of CRM at sea
____________________________________________________________________________________

 Cruise   Start    End      Batch  Cell  N    TA     S.D.  TCO2   S.D.  pH    S.D. 
          date     date                       avg          avg          avg    
 -------  -------  -------  -----  ---- ---  ------  ---  ------  ---  -----  -----
 I8S/I9S  12/1/94  1/19/95   23    All   49  2221.5  5.1  2004.5  4.1  
                                   5     18  2223.3  4.8  2003.8  2.5  
                                   6     18  2220.8  4.0  2008.0  3.1  
                                   20    13  2220.0  6.4  2001.4  3.8  
 I9N      1/24/95  3/6/95    23    All  138  2216.2  3.3  2000.1  3.5  7.891  0.005 
                                   5     68  2215.0  3.3  1999.1  3.3  7.892  0.004 
                                   6     65  2217.5  3.3  2001.3  3.3  7.891  0.005 
                                   20     5  2214.2  3.1  1996.5  3.5  7.895  0.007 
 I8N/I5E  3/10/95  4/16/95   23    All   80  2211.6  4.9  1997.0  3.0  7.890  0.006 
                                   5     36  2213.0  5.5  1998.6  3.8  7.890  0.005 
                                   6     44  2210.1  3.6  1996.2  2.6  7.890  0.007 
 I3       4/20/95  6/7/95    23    All   65  2215.4  1.4  2002.1  1.4  7.894  0.005 
                                   2     33  2215.7  1.3  2000.7  1.4  7.898  0.006 
                                   13    35  2215.0  1.4  2003.6  1.3  7.890  0.004 
                             26    All   30  2178.0  1.2  1984.8  1.2  7.858  0.004 
                                   2     14  2178.3  1.3  1983.3  1.2  7.862  0.003 
                                   13    16  2177.7  1.2  1986.0  1.1  7.855  0.004 
 I5W/I4   6/11/95  7/11/95   26    All   79  2182.6  3.8  1990.2  3.4  
                                   2     41  2183.3  3.9  1988.0  2.4  
                                   13    38  2182.0  3.5  1992.9  2.3  
 I7N      7/15/95  8/24/95   26    All   59  2184.0  5.7  1984.7  3.4  7.862  0.009 
                                   2     33  2186.2  3.1  1984.3  2.6  7.862  0.009 
                                   13    26  2181.5  7.4  1985.2  4.0  7.858  0.006 
                             27    All    8  2221.5  3.1  1995.5  1.4  7.916  0.005 
                                   2      4  2221.4  2.4  1994.9  1.4  7.914  0.005 
                                   13     4  2221.5  4.1  1996.0  1.5  7.918  0.006 
                             23    All   10  2222.4  7.4  2002.0  4.0  7.896  0.006 
                                   2      5  2227.5  5.8  2003.2  4.1  7.897  0.005 
                                   13     5  2216.2  6.4  1999.9  3.9  7.893  0.009 
 I1       8/29/95  10/18/95  27    All  244  2219.4  3.9  1998.8  5.4  7.906  0.013 
                                   2    123  2220.1  3.2  1995.3  3.2  7.911  0.005 
                                   7     54  2219.6  3.6  1999.7  4.1  7.908  0.013 
                                   13    15  2216.2  4.7  1994.6  4.5  7.909  0.005 
                                   14    52  2217.9  4.5  2006.5  3.6  7.885  0.009 
 I10      11/6/95  11/24/95  27    All   62  2212.9  4.0  1991.3  2.9  7.912  0.006 
                                   11    30  2212.3  4.5  1989.6  2.4  7.914  0.005 
                                   16    32  2213.5  3.5  1993.1  2.0  7.910  0.006 
 I8R      9/23/95  10/24/95  29    All   36  2184.2  1.8  1914.8  2.4  8.006  0.006 
 NOAA Cruise                       4      9  2185.5  1.7  1914.5  1.9  8.006  0.005 
                                   17    17  2183.9  1.6  1914.4  2.2  8.007  0.005 
                                   18    10  2183.4  2.1  1915.7  3.1  8.004  0.009 
                             24    All   10  2216.6  2.3  1998.7  1.7  7.902  0.006 
                                   4      2  2218.5  3.8  1998.6  3.9  7.907  0.004 
                                   17     5  2215.1  0.6  1998.5  1.4  7.902  0.006 
                                   18     3  2217.3  2.6  1998.6  1.7  7.899  0.006 
 I2      11/28/95  1/19/96   27    All   67  2219.4  4.5  1994.0  2.8  7.916  0.005 
                                   11    36  2219.9  5.7  1993.1  3.3  7.918  0.005
                                   16    31  2218.9  3.2  1994.7  2.2  7.915  0.006 
                             30    All    9  2204.6  2.7  1996.8  2.1  7.879  0.004 
                                   11     4  2205.3  2.3  1995.0  2.2  7.880  0.002 
                                   16     5  2204.0  3.0  1998.4  0.8  7.879  0.006 
____________________________________________________________________________________


TABLE 3: The overall precision of at sea TA, TCO2, and pH measurements on the 
         Certified Reference Material 
                  _________________________________________

                               Precision 1σ   Number of 
                   Parameters   (µmol kg-1)   measurements 
                   ----------  -------------  ------------
                   TA              4.2            949 
                   TCO             4.1           9472 
                   pH              0.007          793(a)  
                  _________________________________________
                  (a) The numbers of the pH measurements 
                      were less than for TA and TCO2 be-
                      cause some values were not recorded.


Fig. 2.  The reproducibility of the titration pH measurements made on 
         Certified Reference Material on the Indian Ocean Study.
Fig. 3.  The reproducibility of the titration TCO2 measurements made on 
         Certified Reference Material on the Indian Ocean Study.
Fig. 4.  The reproducibility of the titration TA measurements made on 
         Certified Reference Material on the Indian Ocean Study.


3.2.2.  Long term stability of a cell performance

The at sea TA measurements on the CRMs can be used to examine the long-term 
stability of the cells used during the cruises. Overall, the TA results 
obtained using cells for a given cruise did not show any systematic trends. 
Differences in TA between laboratory and field measurements remained 
unchanged over the entire period of each cruise. However, inter-cruise 
variations in TA between laboratory and field results were observed when the 
same cells were used. For instance, cells 2 and 13 were used for four 
consecutive cruises over the period of six months. When these two cells were 
used on the first cruise (I3), the field measurements agreed to within 
±2 µmol/kg-1 with the values obtained in the laboratory. These small 
discrepancies are within the precision of our measurements. When the same 
cells were used for the later cruises, the differences in TA between 
laboratory and field measurements became significantly larger (9 µmol/kg-1). 
As mentioned in Section 3.2.1, these larger differences can be attributed to 
changes in the assigned volume of the cells due to repositioning of a 
reference electrode. These inter-cruise variations in TA can be corrected by 
normalizing the measured values obtained during the cruises using the 
corrections required to reproduce the values assigned for the CRMs by SIO 
(Table 4). This correction was applied using


                             ∆ = TA(meas,CRM)-CRM)                         (4)

                     TA(corr.) = TA(meas.) x [CRM/(CRM+∆)]                 (5)

where CRM is the SIO-certified values.


TABLE 4: Differences between TA measurements made at sea and values measured 
         in the laboratory (SIO)
______________________________________________________________________________

 Cell  I8S/I9S  I9N  I8N/I5E   I3     I5W/I4   I7N    I1   I8R   I10    I2 
 ----  -------  ---  -------  ------  ------  ------  ---  ---  ----  -------
   2                         +2.6(a)   +6.7  +9.9(a) +5.2  
   4                                                       0.7 
   5    +10.6  +2.3   +0.3   
   6    +8.1   +4.8   -2.6   
   7                                                 +4.7  
  11                                                            -2.6  +4.8(a) 
  13                         +2.1(a)   +6.0  +4.9(a) +1.3  
  14                                                 +3.0  
  16                                                            -1.4  +3.7(a) 
  17                                                      -0.9 
  18                                                      -1.4 
  20    +7.3   +1.5   
______________________________________________________________________________
(a)Based on the weighted average on different CRM. 


3.3. CROSSOVER ANALYSIS

In order to cross-check our estimates of accuracy of the TA data, which are 
derived from analyses of CRMs, we examined the agreement between TA 
measurements made at identical locations on different legs of the Indian 
Ocean expedition. All of these comparisons have been made after applying the 
corrections given in Table 4. The implicit assumption is that temporal and 
spatial gradients of TA concentrations in the deep ocean are small relative 
to measurement accuracy, so that water sampled at the same location in the 
deep ocean at two different times should have near-identical values of TA. In 
practice, vertical gradients of TA can be significant relative to measurement 
accuracy and there can also be significant vertical motions in the deep 
ocean. Hence, measurements made at the same geographical location cannot be 
compared simply on the basis of their common depth. Because most motion in 
the ocean interior takes place along surfaces of constant density 
(isopycnals), it is preferable to compare concentrations using density as the 
frame of reference rather than depth.


TABLE 5: Crossover results for the TA measurements made in the Indian Ocean 
         _________________________________________________
         
          Number  Stations      Legs               ∆TA    
          ------  ------------  ---------------  --------
            1     927,929,931,  I1-I7N            1.7±1.0    
                  780,782,784    
            2     987,990,266,  I1-I9N           -2.1±5.9    
                  268,270    
            3     996,998,      I1-I9Nb           1.2±0.8    
                  233,235    
            4     1205,728,     I2-I7N            5.6±2.4    
                  730    
            5     1137,1139,    I2-I9N/I5E        3.4±2.2    
                  320,324    
            6     1094,1096,    I2-I9N           -3.4±1.4    
                  191,193    
            7     1078,1075     I2-I10            1.8±2.4    
            8     705,547,549   I5W/I4-I3         0.7±1.7    
            9     498,499,501,  I3-I8N/I5E       -0.8±2.3    
                  346,348    
           10     472,169       I3-I9N           -0.8±0.6    
           11     1039,452,454  I10-I3           -1.0±0.7    
           12     404,406,408,  I8N/I5E-I8S/I9S  -2.7±3.8    
                  9,11,13    
           13     861,808       I1-I7N            0.3±0.6    
           14     709,707       I7N-I5W/I4        2.4±1.7    
           15     966,968,969,  I1-I8N/I5E       -4.2±4.5    
                  283,287
         _________________________________________________


Our crossover analyses were performed as follows.

(1) Locations at which different cruise legs intersected were identified as 
    crossover points. These are identified in Table 5 and Fig. 1.

(2) Stations located in the immediate proximity of these crossover points, 
    for which TA data existed, were selected for the comparison. In general, 
    stations located within 100 km of the crossover location were selected.

(3) For water samples collected below 2500 m, smooth curves were fit through 
    the TA data as a function of the density anomaly referenced to 3000 db 
    (sigma-3) using Cleveland's loess or smoother local regression (Cleveland 
    and Devlin, 1988; Cleveland and Grosse, 1991; Chambers and Hastie, 1991). A 
    separate fit was performed to the data collected from each of the two 
    intersecting legs. The tension parameter for the smoother was adjusted 
    subjectively to give a 'reasonable' fit to the data at the majority of the 
    crossover locations, and the same value for the tension parameter was used 
    for all of the crossovers. Hence, while the fits to the data may not 
    necessarily represent the best possible at each individual crossover point, 
    the smoothing function has been applied consistently. It is important to 
    note that the comparison of the data at the crossover points does not depend 
    on the fitting algorithm within the experimental error.

(4) For each crossover, the difference between the two smooth curves was 
    evaluated at 50 evenly spaced intervals that covered the density range over 
    which the two data sets overlapped. A mean and a standard deviation of the 
    difference between the two curves was estimated based on these 50 values, 
    and these values are reported in Table 5 and shown in Fig. 5. An example of 
    the crossover for cruises I3-I5W/I4 is shown in Fig. 6.


Fig. 5.  Summary of the TA reproducibility for crossover points in the Indian 
         Ocean.
Fig. 6.  Results for a typical crossover comparison (I3-I5W/I4) in the Indian 
         Ocean.


The results of the crossover analysis indicate that absolute leg-to-leg 
differences are always <6 µmol/kg-1. Note that the comparisons were evaluated 
consistently such that the fit to data from the earlier leg at each crossover 
was subtracted from the fit to the later leg's data. Any uncorrected, long-
term, monotonic drift in the calibration of the titrators over the course of 
the Indian Ocean expedition would therefore tend to result in a non-zero 
value for the overall mean of these differences. The overall mean and 
standard deviation of the differences at all the crossovers are 2.1±2.1 µmol 
kg_1. In general, the results of the crossover analysis are quite consistent 
with the overall reproducibility of the CRM analyses (±4 µmol/kg-1) over the 
duration of the entire Survey.



4. CONCLUSION

At-sea total alkalinity measurements on the several CRM batches demonstrated 
that the measurements made by various investigators were precise to about ±4 
µmol/kg-1. This level of the precision of at sea measurements was 
approximately two times worse than that in the laboratory. Differences in the 
precision between different investigators suggest that the performance of TA 
measurements was dependent upon the operators. The inter-cruise variations in 
total alkalinity between laboratory and field results clearly demonstrate 
that CRMs are an essential component to monitor the performance of titration 
systems and increase the accuracy for total alkalinity measurements in the 
field.



ACKNOWLEDGEMENTS

The authors wish to acknowledge the support of the Department of Energy for 
their support of the CO2 studies. The WOCE cruises were supported by the 
National Science Foundation, as was some of the laboratory work related to 
the preparation and standardization of Certified Reference Material.



REFERENCES

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    alkalinity and total carbon dioxide in seawater by potentiometric titration: 
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Chambers, J.M., Hastie, T.J., 1991. Stat. Models Sci., 309-376.

Cleveland, W.S. and Devlin, S.J., 1988. Locally-weighted regression: an 
    approach to regression analysis by local fitting. J. Am. Statist. Assoc. 83, 
    pp. 596-610

Cleveland, W.S., Grosse, E., 1991. Computational Methods for Local 
    Regression. Stat. Comput., Vol. 1.
    
Dickson, A.G., 1981. An exact definition of total alkalinity and a procedure 
    for the estimation of alkalinity and total CO2 from titration data. Deep-Sea 
    Res. 28, pp. 609-623 

Dickson, A.G., 1984. pH scales and proton-transfer reactions in saline media 
    such as seawater. Geochim. Cosmochim. Acta 48, pp. 2299-2308
    
Dickson, A.G., 1990. The oceanic carbon dioxide system: planning for quality 
    data. US JGOFS News 2 2, p. 10
    
Dickson, A.G., 1990. Thermodynamics of the dissociation of boric acid in 
    synthetic seawater from 273.15 to 318.15 K. Deep-Sea Res. 37, pp. 755-766 
    
Dickson, A.G., 1990. Standard potential of the (AgCl+1/2 H2=Ag+HCl(aq)) cell 
    and the dissociation of bisulfate ion in synthetic sea water from 273.15 to 
    318.15 K. J. Chem. Thermodyn. 22, pp. 113-127

Dickson, A.G. and Riley, J.P., 1979. The estimation of acid dissociation 
    constants in sea water media from potentiometric titrations with strong 
    base: I. The ionic production of water-KW. Mar. Chem. 78, pp. 89-99 

Dickson, A.G. and Millero, F.J., 1987. A comparison of the equilibrium 
    constants for the dissociation of carbonic acid in seawater media. Deep-Sea 
    Res. 34, pp. 1733-1743 

DOE, 1994. Handbook of methods for the analysis of the various parameters of 
    the carbon dioxide system in sea water, In: Dickson, A.G., Goyet, C. (Eds.), 
    Version 2, ORNL/CDIAC-74.

Johansson, O. and Wedborg, M., 1982. On the evaluation of potentiometric 
    titrations of seawater with hydrochloric acid. Oceanol. Acta 5, pp. 209-218
    
Johnson, K.M., Dickson, A.G., Eischeid, G., Goyet, C., Guenther, P., Key, 
    R.M., Millero, F.J., Purkerson, D., Sabine, C.L., Schottle, R.G., Wallace, 
    D.R.W., Wilke, R.J. and Winn, C.D., 1998. Coulometric total carbon dioxide 
    analysis for marine studies: Assessment of the quality of total inorganic 
    carbon measurements made during the US Indian Ocean CO2 Survey 1994-1996. 
    Mar. Chem. 63, pp. 21-37
    
Marinenko, G. and Taylor, J.K., 1968. Electrochemical equivalents of benzoic 
    and oxalic acid. Anal. Chem. 40, pp. 1645-1651
    
Millero, F.J., 1995. The thermodynamics of the carbon dioxide system in 
    oceans. Geochim. Cosmochim. Acta 59, pp. 661-677
    
Millero, F.J. and Poisson, A., 1981. International equation of state of 
    seawater. Deep-Sea Res. 28, pp. 625-629
    
Millero, F.J., Laferriere, A. and Chetirkin, P.V., 1977. The partial molal 
    volumes of electrolytes in 0.725 m sodium chloride solutions at 25°C. J. 
    Phys. Chem. 81, pp. 1737-1745

Millero, F.J., Zhang, J.Z., Lee, K. and Campbell, D.M., 1993. Titration 
    alkalinity of seawater. Mar. Chem. 44, pp. 153-160
    
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    and bases. J. Res. Natl. Bur. Stds. 63A, pp. 153-159
    















                                  APPENDIX D:

                        REPRINT OF PERTINENT LITERATURE




Sabine, C. L., R. M. Key, K. M. Johnson, F. J. Millero, A. Poisson, 
J. L. Sarmiento, D. W. R. Wallace, and C. D. Winn (1999), Anthropogenic 
CO2 Inventory of the Indian Ocean, Global Biogeochem. Cycles, 13(1), 179-198.





                ANTHROPOGENIC CO2 INVENTORY OF THE INDIAN OCEAN

C.L. Sabine,(1) R.M. Key,(1) K.M. Johnson,(2) F.J. Millero,(3) A. Poisson,(4) 
J.L. Sarmiento, D.W.R. Wallace,(2,5) and C.D. Winn,(6,7)

(1) Department of Geosciences, Princeton University, Princeton, New Jersey.
(2) Oceanographic and Atmospheric Sciences Division, Brookhaven National 
    Laboratory, Upton, New York.
(3) Rosenstiel School of Marine and Atmospheric Science, University of Miami, 
    Miami, Florida.
(4) Laboratoire de Physique et Chimie Marines, Universite Pierre et Marie 
    Curie, Paris.
(5) Now at Institut für Meereskunde, Universität Kiel.
(6) Department of Oceanography, University of Hawaii at Manoa, Honolulu, 
    Hawaii.
(7) Now at Hawaii Pacific University, Kaneohe, Hawaii.



GLOBAL BIOGEOCHEMICAL CYCLES, VOL. 13, NO.1, PAGES 179-198, MARCH 1999
Copyright 1999 by the American Geophysical Union.
Paper number 1998GB900022.
0886-62361991l998GB900022$12.00




ABSTRACT. 

This study presents basin-wide anthropogenic CO2 inventory estimates for the 
Indian Ocean based on measurements from the World Ocean Circulation 
Experiment/Joint Global Ocean Flux Study global survey. These estimates 
employed slightly modified ∆C* and time series techniques originally proposed 
by Gruber et al. [1996] and Wallace [1995], respectively. Together, the two 
methods yield the total oceanic anthropogenic CO2 and the carbon increase 
over the past 2 decades. The highest concentrations and the deepest 
penetrations of anthropogenic carbon are associated with the Subtropical 
Convergence at around 30° to 40°S. With both techniques, the lowest 
anthropogenic CO2 column inventories are observed south of 50°S. The total 
anthropogenic CO2 inventory north of 35°S was 13.6±2 Pg C in 1995. The 
inventory increase since GEOSECS (Geochemical Ocean Sections Program) was 
4.1±1 Pg C for the same area. Approximately 6.7±1 Pg C are stored in the 
Indian sector of the Southern Ocean, giving a total Indian Ocean inventory of 
20.3 ±3 Pg C for 1995. These estimates are compared to anthropogenic CO2 
inventories estimated by the Princeton ocean biogeochemistry model. The model 
predicts an Indian Ocean sink north of 35°S that is only 0.61-0.68 times the 
results presented here; while the Southern Ocean sink is nearly 2.6 times 
higher than the measurement-based estimate. These results clearly identify 
areas in the models that need further examination and provide a good baseline 
for future studies of the anthropogenic inventory.



1.  INTRODUCTION

The current Intergovernmental Panel on Climate Change (IPCC) estimate for the 
oceanic sink of anthropogenic CO2 (2.0 ±D.8 Pg C yr-I) is based primarily on 
ocean models [e.g., Sarmiento et al., 1992; Sarmiento and Sundquist, 1992; 
Siegenthaler and Sarmiento, 1993; Siegenthaler and Joos, 1992; Stocker et 
al., 1994], atmospheric models [e.g., Keeling et al., 1989; Keeling and 
Shertz, 1992] or on the oceanic distribution of related species such as δ13C 
[Quay et al., 1992]. Although the basic assumptions used in these methods are 
reasonably well grounded, there will always be room for doubt with indirect 
approaches. Direct estimates of the oceanic CO2 sink, however, have been 
primarily limited by a lack of high-quality data on a global scale.

Two general approaches can be used to estimate the uptake of anthropogenic 
CO2 by the oceans. One approach, initially proposed by Tans et al. [1990], is 
to use direct measurements of the air-sea difference in CO2 partial pressure 
together with global winds and a gas exchange coefficient to estimate the net 
transfer of CO2 into the oceans. These estimates, together with an 
atmospheric transport model, predicted that the oceanic sink was only 0.3 to 
0.8 Pg C yr-', much smaller than the model predictions. The difficulty with 
the ∆C02 approach lies both in the large uncertainty in the wind speed 
dependence of the air-sea gas exchange velocity and in the ability to 
properly represent the large temporal and spatial variability of the surface 
ocean pC02 because of a lack of seasonal, global data coverage. This estimate 
has recently been revised to 0.6 to 1.34 Pg C yr-I with the addition of more 
data and a lateral advection-diffusion transport equation to help with the 
necessary temporal and spatial interpolations [Takahashi et al., 1997].

A second approach, which avoids many of the problems of temporal variability, 
is to estimate the inventory of anthropogenic CO2 stored in the oceans 
interior based on inorganic carbon measurements. Again, the problem with this 
approach in the past has been a lack of high-quality global data coverage. As 
pointed out by Broecker et al. [1979] after completion of the last global 
oceanographic survey, GEOSECS (Geochemical Ocean Sections Program), the 
precision of ocean carbon measurements at that time was two orders of 
magnitude smaller than the predicted 0.035% annual increase in surface ocean 
dissolved inorganic carbon. Nearly 20 years have passed since GEOSECS, and 
the quality of today's carbon measurements has improved significantly.

This is the first of several papers aimed at estimating the anthropogenic CO2 
inventory of the oceans based on the recent global survey of CO2 in the 
oceans. The survey was conducted as part of the JGOFS (Joint Global Ocean 
Flux Study) in close cooperation with the WOCE-HP (World Ocean Circulation 
Experiment - Hydrographic Programme). This program was a multiyear effort to 
collect high-precision inorganic carbon data with the highest possible 
spatial resolution on a global scale. This paper will focus on anthropogenic 
CO2 estimates for the Indian Ocean. Papers will soon follow with estimates 
for the other major ocean basins, with the ultimate goal of generating an 
estimate of the global oceanic anthropogenic CO2 sink based on direct carbon 
system measurements. The strength of these calculations lies not only in our 
ability to directly estimate the magnitude of the oceanic anthropogenic CO2 
sink but also in the fact that these estimates can be directly compared to 
anthropogenic CO2 inventories estimated by carbon cycle ocean general 
circulation models (GCMs). The two methods described here provide information 
over different timescales. The combined results place strong constraints on 
the uptake rate for anthropogenic CO2 and are useful for identifying 
weaknesses in the models.



2.  METHODS

Estimates of the anthropogenic CO2 inventory are determined from measured 
values using two different techniques. The first technique, referred to as 
the "time series" approach, is based on quantifying the increase in total 
carbon dioxide (TC02) since GEOSECS. The second approach quantifies the total 
anthropogenic CO2 inventory using a quasi-conservative tracer, ∆C*. Although 
the general idea for both techniques has been around for a long time, recent 
improvements in the estimation of the preserved end-member concentrations 
together with significant Improvements in the accuracy and spatial coverage 
of global carbon data give us much more confidence in these results. Given 
the difficulty of isolating the anthropogenic signal from the large TC02 
background, however, it is relevant to summarize the quality of the carbon 
data set and the techniques used to estimate the anthropogenic signal.


2.1.  DATA QUALITY

Over 20,000 water samples collected between December 1994 and July 1996 as 
part of the U.S. WOCE Indian Ocean survey were analyzed for both TC02 and 
total alkalinity (TA) using standard coulometric and potentiometric 
techniques, respectively. Figure 1 shows the locations of the 1352 stations 
occupied by U.S. WOCE as part of the Indian Ocean survey together with the 
station locations from the GEOSECS Indian Ocean Survey and the French INDIGO 
I, II, and III and CIVA-1 (WOCE designation I6S) Cruises Details of the 
WOCE/JGOFS Indian Ocean CO2 measurement program, including personnel, 
sampling procedures, measurement protocols and data quality assurance/quality 
control checks are described elsewhere [Johnson et al., 1998; Millero et al., 
1998a]. Calibrations of both the TC02 and TA systems were checked 
approximately every 12 hours by analyzing Certified Reference Material (CRM) 
samples with known concentrations of TC02 and TA [Dickson, 1990] (A.G. 
Dickson, Oceanic carbon dioxide quality control at http://www-mpl.ucsd. 
edulpeople/adicksonlC02_QC/, 1998). On the basis of these CRM analyses the 
accuracy of the TC02 and TA measurements was estimated to be ±2 and ±4 µmol 
kg-1, respectively. Primary hydrographic data from the conductivity- 
temperature-depth/Rosette were collected and analyzed following standard 
procedures [Millard, 1982]. Samples were collected for salinity on every 
bottle and analyzed with an Autosal salinometer using standard techniques 
[UNESCO, 1981]. Oxygen samples were analyzed with an automated system using a 
modified Winkler technique [Culberson et al., 1991]. Nutrients were analyzed 
on a four-channel Technicon AutoAnalyzer II following the methods of Gordon 
et al. [1992]. Chlorofluorocarbon samples were analyzed on a gas 
chromatograph using the techniques of Bullister and Weiss [1988]. Complete 
details of the analytical protocols and personnel can be obtained from the 
individual cruise reports available through the WOCE Office. 


FIGURE 1:  Station locations for WOCE Indian Ocean (circles), 
           CIVA-1/I6S (crosses), INDIGO I (stars), INDIGO 
           II (inverted triangles), INDIGO III (triangles), 
           and GEOSECS (solid squares) Indian Ocean Surveys. 
           Numbered boxes indicate location of crossovers 
           discussed in the text. Map generated using Generic 
           Mapping Tools version 3 [Wessel and Smith, 1995].


All of the data available at the time this manuscript was written have been 
included in the Indian Ocean analysis. For the primary hydrographic and 
nutrient data this means that the preliminary values available at the 
conclusion of the cruise were used. While we would prefer to use the final 
hydrographic data, typical post cruise corrections for the WOCE data sets are 
well below noise level for these calculations. Preliminary to semifinal 
chlorofluorocarbon (CFC) data were used to estimate the water age necessary 
for one of the correction terms in the ∆C* method. Although post cruise blank 
corrections can influence the final CFC concentrations, an examination of the 
existing data (except 18NI5E because data were not available at time of 
writing) indicated that the CFC-ll and CFC-12 age comparisons as well as 
comparisons of the data from one leg to the next were reasonably consistent 
with each other. The calculations were limited to waters with CFC-12 ages of 
less than 40 years where potential blank corrections are a relatively small 
fraction of the signal and mixing effects are minimized. The carbon data, 
which primarily influence the quality of the calculations, have all been 
calibrated and finalized as discussed briefly below.

Examination of Figure 1 reveals that although the WOCE survey was extensive, 
a large data gap exists in the southwestern Indian Ocean. To fill in this 
gap, data from the three French survey legs INDIGO I (February-March 1985), 
IT (April 1986) and 1lI (January-February 1987) as well as the more recent 
French cruise CIVA-1 (February-March 1993 (WOCE designation 16S» were 
included in the analysis [Poisson et al., 1988; 1989; 1990]. TC02 and TA were 
analyzed on the INDIGO cruises using standard potentiometric titration 
techniques developed by Edmond [1970]. Potentiometric titrations were also 
used to analyze the TA samples on CIVA-1, but the TC02 samples were analyzed 
using the coulometric techniques of Johnson et al. [1985]. The internal 
consistency of these cruises was examined by comparing carbon values in the 
deep waters (pressure> 2500 dbars) at the intersections of different legs. 
The stations selected for each crossover were those with carbon values which 
were closest to the intersection point. Smooth curves were fit through the 
data from each cruise as a function of sigma- 3 (density anomaly referenced 
to 3000 dbars) using Cleveland's loess function [Cleveland and Devlin, 1988; 
Cleveland et al., 1992]. The difference between the curves was evaluated at 
50 evenly spaced intervals that covered the density range over which the two 
data sets overlapped. The mean and standard deviation of the difference in TA 
and TC02 at the 35 intersections identified in Figure 1 are shown in Figure 
2. The long-term stability of the WOCE/JGOFS measurements can be estimated 
from the first 17 crossover results. The mean of the absolute values for the 
leg-to-leg differences was less than the estimated accuracy for both TC02 
(1.8 ±0.8 µmol kg-1) and TA (2.4 ±1.6 µmol kg-1). Although there is only one 
reliable crossover point between the WOCE/JGOFS cruises and the CIVA-1 (I6S) 
cruise, the differences for both parameters are within the estimated accuracy 
of the measurements. Results from the analysis of CRM samples on the CIVA-1 
cruise also support the quality of the measurements. Some of the older INDIGO 
cruises, however, did appear to have offsets relative to the WOCE/JGOFS and 
CIVA-1 data. INDIGO I and IT alkalinity values averaged 6.5 µmol kg-1 high 
and 6.8 µmol kg-1 low, respectively, while the INDIGO 1lI alkalinity values 
showed no clear offset. The INDIGO TC02 values were all consistently high 
relative to WOCE/JGOFS and CIVA-1, with differences of 10.7,9.4, and 6.4 µmol 
kg-1, respectively. These offsets are consistent with differences observed 
between at-sea values and replicate samples run at C.D. Keeling's shore-based 
TC02 facility (P. Guenther, personal communication, 1998). Since the INDIGO 
cruises were run prior to the introduction of CRMs, these offsets were 
presumed to be calibration differences, and each leg was adjusted to bring 
the values in line with the remaining cruises. The dotted boxes in Figure 2 
show the original offsets at the crossovers. The solid boxes show the final 
offsets used in the following calculations. The means of the absolute values 
for the leg-to-leg differences for all 35 crossover analyses suggest that the 
final data set is internally consistent to ± 2.2 and 3.0 µmol kg-1 for TC02 
and TA, respectively.


2.2.  "TIME SERIES" CALCULATIONS

The "time series" method for estimating the increase in the anthropogenic 
inventory uses measurements of TC02 made at a certain point in time to 
develop a predictive equation based on a multiple linear regression of the 
observed TC02 and simultaneously measured parameters such as temperature, 
salinity, oxygen, and TA (or silicate). These empirical multiparameter 
relationships have been shown to hold over large spatial scales, and their 
use drastically reduces the complicating effects of natural variability in 
determining temporal trends [Brewer et al., 1995; Wallace, 1995; Brewer et 
al., 1997]. The TC02 residuals from such predictive equations can be compared 
directly with patterns of residuals evaluated using the same predictive 
equation with TA, oxygen, and hydrographic data collected at different times 
(e.g., over decadal intervals). Since the uptake of anthropogenic CO2 will 
increase the TC02 of the waters but will not directly affect the concentrations 
of the fit parameters, systematic changes in the magnitude and distribution of 
the TC02 residuals over time provide a direct estimate of the oceanic CO2 
inventory change due to the uptake of anthropogenic CO2. The most comprehensive 
historical carbon data set for the Indian Ocean is from the GEOSECS expedition. 
By examining the WOCE data relative to that collected during the 1977-1978 
GEOSECS Indian Ocean Survey, the increase in anthropogenic inventory over the 
last 18 years can be estimated.


2.2.1.  GEOSECS FIT 

All of the GEOSECS data from the Indian Ocean (excluding Gulf of Aden and Red 
Sea regions) were fit with a single predictive equation as a function of 
potential temperature (9), salinity (S), apparent oxygen utilization (AOU), 
and TA. To minimize the influence of short-term temporal variability, only 
data from pressures greater than 200 dbars were included in the fit. Despite 
the large area covered, the GEOSECS TC02 values can be predicted from this 
equation to ± 5.2 µmol kg-1 (~ =0.992 and N = 1120). There is, however, a 
pattern in the residuals that correlates with observed hydrographic regions 
in the Indian Ocean (Figure 3).

In an attempt to improve the fit, a categorical variable based on region was 
added to the regression. The categorical variable differs from the other 
continuous variables by the fact that it is either applied or not applied 
depending on whether the sample is located within the region. The regions 
were defined as follows: I, Arabian Sea (north of l0°N and west of 78°E); 2, 
North of 10°S (excluding Arabian Sea); 3, Chemical Front (21°S to 10°S); 4, 
Central Gyre (35°S to 21°S); and 5, Southern Ocean (south of 35°S)

The addition of the regional variable resulted in a marginal improvement in 
the fit (~ =0.993 and (J =4.9 µmol kg-1) but more importantly, removed the 
regional bias in the predictive equation. The coefficients of the final fit 
are shown in Figure 4 along with a plot of the measured versus calculated 
TC02 values for all of the points used in the fit. The resulting equation was 
then used to generate TC02 values for each of the WOCE sample locations based 
on the measured temperature, salinity, oxygen, and TA values. The difference 
between the measured TC02 and the predicted TC02 reflects the CO2 increase in 
the time between the two cruises. For this work the difference is referred to 
as "excess CO2,"


FIGURE 2:  Mean difference between deep water values of (a) TA 
           and (b) TC02 for cruise intersections identified in 
           Figure 1. Bars indicate one standard deviation. Dotted 
           boxes indicate difference before adjustment (see 
           explanation in text).

FIGURE 3:  Box and whiskers plot of residuals from a multiple linear 
           regression of GEOSECS Indian Ocean data (pressure> 200 
           dbars) fit without the regional designator versus 
           oceanographic region: TC02 = 706.5 + 7.7S - 6.689 + 
           0.513TA + 0.7257AOU. Solid boxes cover the range of ±1 
           standard deviation about the mean. White lines within 
           the boxes indicate median values. The whiskers indicate 
           the range of data within the 99% confidence interval. 
           The bars outside the whiskers give the values of 
           outliers in the data set.

FIGURE 4:  Plot of measured GEOSECS TC02 versus the calculated 
           values. Solid line shows 1:1 relationship. The dashed 
           lines indicate the 99% confidence interval for the 
           fit. Text gives coefficients and related statistics. 
           The column labeled "Pr(>|T|)" gives the probability 
           that the T value in the previous column is larger 
           than the T table value in a student T test.


The residual method of estimating excess CO2 was applied to the water column 
below 200 dbars. The surface waters, however, are dominated by seasonal 
variability which can bias the residual calculations. The excess CO2 of the 
surface waters therefore was determined from the difference in the estimated 
annual mean TC02 concentrations between GEOSECS and WOCE. The annual mean 
TC02 concentration was calculated from TA and surface water ƒC02. The surface 
alkalinity was estimated from the gridded annual mean salinity and 
temperature values of Levitus et al. [1994] and Levitus and Boyer [1994] 
using a multiple linear fit of the WOCE/JGOFS surface (pressure < 60 dbars) 
TA data to the measured surface temperature and salinity. The 1978 and 1995 
surface water jC02 concentrations were estimated from the annual mean 
atmospheric concentration for the 2 years. and the annual mean ∆pC02 values 
estimated from the full correction scheme of Takahashi et al. [1997]. The 
excess TC02 values between the surface and 200 dbars were estimated with a 
linear approximation between the surface and 200 dbars values for each 1° 
grid box.


2.2.2. DATA CONSISTENCY. 

One of the major concerns with the time series technique is the necessity of 
having two data sets that are consistent with each other. This consistency 
can be well documented for both TC02 and TA today through the use of 
certified reference materials (CRMs) supplied by A. Dickson of Scripps 
Institute of Oceanography (SIO). Since CRMs were not available at the time of 
GEOSECS. the only way to infer consistency with the WOCE data set is to 
assume the deep water carbon distributions have not changed since GEOSECS. 
The most reliable way to compare the two data sets is to examine the 
difference between the predicted TC02 and the measured TC02 (excess CO2) in 
deep waters. The basic assumption with this technique is that the correlation 
between the different hydrographic parameters in the deep waters does not 
change with time. Given the long residence time of the deep and bottom waters 
in the ocean. this should be a reasonable assumption. This technique has the 
advantage that it implicitly accounts for the possibility of real variability 
in hydrographic properties between the two expeditions which would not be 
taken into account by simply comparing carbon profiles.

Examination of the excess CO2 values in waters that should be free of 
anthropogenic CO2 (pressures> 2000 dbars and containing no detectable 
chlorofluorocarbons) revealed that the GEOSECS values were 22.5 ±3 µmol kg-1 
higher than the comparable WOCE measurements. This difference is comparable 
to the correction of 18 ± 7 µmol kg-1 noted by Weiss et al. [1983] to make 
the TC02 measurements consistent with the TA and discrete CO2 partial 
pressure measurements based on the Merbach et al. [1973] dissociation 
constants. Additional support for an adjustment of the original GEOSECS data 
comes from C. D. Keeling's shore-based analysis ofTC02 samples collected on 
both the GEOSECS and the WOCE/JGOFS expeditions. Weiss et al. [1983] point 
out that the shore-based analyses of Keeling were systematically smaller than 
the at-sea measurements by 16.5 ± 5 µmol kg-1 during GEOSECS. Similar 
comparisons between the WOCE/JGOFS at-sea measurements with Keeling's shore-
based analyses indicate that the shore based samples are approximately 5 µmol 
kg-1 higher than the at sea values (P. Guenther. personal communication. 
1998). Together. the GEOSECS-Keeling-WOCE/JGOFS combination suggests an 
offset of 21.5 µmol kg-1 between GEOSECS and WOCE/JGOFS at-sea measurements. 
It is also important to note that there is no indication of a depth or 
concentration dependent correction for the GEOSECS data. The shore-based 
comparison. based only on samples collected at the surface. is within I µmol 
kg-1 of the deep comparison described above. On the basis of these results a 
constant correction of the -22.5 µmol kg-1 was applied to the GEOSECS TC02 
values to improve the consistency of the two data sets.

Ideally. the data used in the time series calculations would cover the same 
geographic region with as much of a time difference as possible. The trade-
off. however. is that the quality and spatial coverage of the older data sets 
is generally very limited. Given the relatively small area of overlap between 
the WOCE/JGOFS and INDIGO data sets and the shorter time difference between 
cruises (9 years versus 18 years for WOCE - GEOSECS). the time series 
analysis was limited to a comparison between WOCE/JGOFS and GEOSECS in the 
main Indian Ocean basin.


2.2.3.  EVALUATION OF ERRORS 

An estimate of the random errors associated with the excess CO2 calculation 
can be made with a simple propagation of errors based on the fit to the 
GEOSECS data and the estimated precision of the WOCE/JGOFS data. With a 
standard deviation of 4.9 µmol kg-1 for the GEOSECS fit and an estimated 
long-term precision of ±2 µmol kg-1 in the WOCE/JGOFS TC02 values the excess 
CO2 error is estimated to be approximately ±5 µmol kg-1. This value compares 
well with the standard deviation of 3.5 µmol kg-1 for the excess CO2 below 
the maximum anthropogenic CO2 penetration depth (pressure> 1500 dbars).

Systematic errors with this technique are very difficult to evaluate. The 
largest potential systematic error is probably associated with the surface 
water estimates. Because the same ∆pC02 value is used to estimate the TC02 
for both years. the excess CO2 (1995 TC02 - 1978 TC02) is not very sensitive 
to potential errors associated with the actual ∆pC02 values used. The surface 
estimate is sensitive. however. to the assumption that the ∆pC02 has not 
changed over time (i.e.. that the surface ocean increase has kept pace with 
the atmospheric increase). It is not likely that the surface ocean has 
increased at a faster rate than the atmosphere. but it is conceivable that 
the rate is slower. The current assumption results in a total inventory of 
0.8 Pg C in the surface layer. If the surface ocean were increasing at half 
the rate of the atmosphere. the systematic bias in the final inventory would 
be around 0.4 Pg C. Below the surface layer the most likely systematic error 
would result from the uncertainty in fitting the GEOSECS data. Systematic 
errors associated with calibration differences between cruises are 
potentially quite large. but the analysis and subsequent correction given in 
section 2.2.2 should remove these biases. The estimated uncertainty for the 
GEOSECS adjustment was ±3 µmol kg-1. If this value is integrated for the area 
north of 35°S between 200 m and the average penetration depth of the excess 
CO2 (~800 m). the potential error would be ±0.9 Pg C. Propagating the errors 
for the surface and deeper layers gives an estimated error of approximately 
±1 Pg C in the total excess CO2 inventory. Clearly, there are other ways of 
estimating the potential errors in these calculations. but we feel that this 
is a reasonable estimate based on the available data.


2.3.  ∆C* CALCULATIONS

Gruber et al. [1996] developed a method to estimate the total anthropogenic 
CO2 inventory which has accumulated in the water column since pre-industrial 
times. Although the details of the calculation are thoroughly discussed by 
Gruber et al. the basic concept of the calculation can be expressed in terms 
of the following equation:

                C(anth)(µmol/kg) = C(m)-∆C(bio)-C(280)-∆C(dis)            (1)

where
     C(anth) anthropogenic carbon concentration;
     C(m)    measured total carbon concentration;
     ∆C(bio) change in TC02 as a result of biological activity;
     C(280)  TC02 of waters in equilibrium with an atmospheric CO2
             concentration of 280 µatm;
     ∆C(dis) air-sea difference in CO2 concentration expressed in µmol
             kg-1 of TC02.

The Gruber et al. technique employs a new quasi-conservative tracer ∆C*, 
which is defined as the difference between the measured TC02 concentration, 
corrected for biology, and the concentration these waters would have at the 
surface in equilibrium with a pre-industrial atmosphere (i.e., ∆C* = C(m) - 
∆C(bio) - C(280)). Rearranging (I) shows that ∆C* reflects both the 
anthropogenic signal and the air-sea CO2 difference (i.e., ∆C* = C(anth) + 
∆C(dis)). The airsea disequilibrium component can then be discriminated from 
the anthropogenic signal using either information about the water age (e.g., 
from transient tracers such as CFCs or 3H-3He) or the distribution of ∆C* in 
regions not affected by the anthropogenic transient. The details of this 
technique will not be covered here except as necessary to explain small 
modifications that were necessary for use with the WOCE Indian Ocean data 
set.


2.3.1.  PREFORMED ALKALINITY EQUATION 

The first modification to the Gruber et al. [1996] technique involved a 
recalculation of the preformed alkalinity equation. The preformed alkalinity 
(Alk^0) of a subsurface water parcel is an estimate of the alkalinity that 
the water had when it was last at the surface. This value is necessary to 
determine the equilibrium concentration (C(280)) of the waters. Gruber et al. 
generated a single global equation for estimating Alk^0 from salinity and the 
conservative tracer "PO" (PO = 02+l70*P) [Broecker, 1974] based on the data 
collected during GEOSECS, South Atlantic Ventilation Experiment, Transient 
Tracers in the Ocean/North Atlantic Study and Transient Tracers in the Ocean/ 
Tropical Atlantic Study. Given the limited representation of the Indian Ocean 
in these data and the improved quality of today's measurements, the Gruber et 
al. fit was examined for a possible bias with respect to the WOCE/JGOFS 
results. Alk^0 values calculated from the Gruber et al. equation were found 
to be, on average, 7 ±12 µmol kg-1 lower than the WOCE/JGOFS measured surface 
alkalinity values. Rather than making assumptions about which parameters 
would provide the best fit to the surface alkalinity data, several possible 
parameters were tested based on previously noted correlations. Although 
salinity has been shown to generally correlate very strongly with surface 
alkalinity [Brewer et al., 1986; Millero et al., 1998b], some areas, such as 
the high-latitude regions, require additional parameters to fit regional 
changes in alkalinity. Some investigators have used temperature as an 
additional variable [e.g., Chen and Pytkowicz, 1979; Chen, 1990; Millero et 
al., 1998b]. Others, such as Gruber et al. [1996], have used other 
conservative tracers to compensate for the regional differences. The best fit 
for the WOCE/JGOFS, INDIGO, and CIVA Indian Ocean data, with pressures less 
than 60 dbars, is given by (2):

                 Alk^0 = 378.1+55.22 x S+0.0716 x PO-1.236 x θ            (2)

Alk^0 has units of µmol kg-1 when salinity (S) is on the practical salinity 
scale, PO is in µmol kg-1, and potential temperature (θ) is in degrees 
Celsius. The standard error in the new Alk^0 estimate is ±8.0 µmol kg-1 based 
on 2250 data points. A standard ANOVA analysis of the fit shows that all four 
terms are highly significant (Table 1). Reevaluating the Alk^0 equation not 
only removed the 7 µmol kg-1 offset of Gruber's equation but also resulted in 
a 35% reduction in the uncertainty. 


TABLE 1: Results From ANOVA Analysis of Alk^0 Fit.
         ____________________________________________________

                   Coefficient  Standard  T Value   Pr(>|T|)
                                 Error
                   -----------  --------  --------  --------
          Intercept  378.1       8.9       42.2715  0.0000
          Salinity    55.22      0.23     235.0369  0.0000
          PO           0.0716    0.0041    17.4693  0.0000
          Theta       -1.236     0.061    -20.3697  0.0000
         ____________________________________________________
          The column labeled "Pr(>rr1)" gives the probability 
          that the T value in the previous column is larger 
          than the T table value in a student T test. Alk^0 
          is preformed alkalinity. an estimate of the alka-
          linity of a parcel of subsurface water when it was 
          last at the surface.


2.3.2.  DENITRIFICATION CORRECTION 

A second modification to the original ∆C* technique was necessary to properly 
account for the anoxic regions in the northern Indian Ocean. The C(bio) term 
in (1) assumes that the remineralization of carbon in the interior of the 
ocean occurs in proportion to the oxygen uptake based on a standard Redfield 
type stoichiometry. The ratios used for these calculations were based on the 
global estimates of Anderson and Sarmiento [1994]. Gruber et al. [1996] 
demonstrated that the errors in the ∆C* calculation due to uncertainties in 
the C:O stoichiometric ratio only become significant for AOU values greater 
than 80 µmol kg-1. Given that most of the anthropogenic CO2 is found in 
relatively shallow waters with low AOU, this error, on average, is small. For 
some regions of the Arabian Sea, however, oxygen depletion can be quite 
extensive at relatively shallow depths [Sen Gupta et al., 1976; Deuser et 
al., 1978; Naqvi and Sen Gupta, 1985]. In areas where the waters become 
anoxic, denitrification can significantly alter the dissolved carbon to 
oxygen ratio [Naqvi and Sen Gupta, 1985; Anderson and Dyrssen, 1994; Gruber 
and Sarmiento, 1997]. The dissolved carbon generated by denitrification shows 
up as high ∆C* values as demonstrated at the northern end of the section in 
Figure 5a. The distribution of ∆C* values along the density surface σθ = 26.9-
27.0 shows maximum values at both the northern and southern ends of the 
section. One would expect the uptake of anthropogenic CO2 to generate the 
highest values close to the outcrop region in the south, but this surface 
does not outcrop in the north. Following the methods of Gruber and Sarmiento 
[1997], the denitrification signal can be estimated using the N* tracer. N* 
is a quasi-conservative tracer which can be used to identify nitrogen (N) 
excess or deficits relative to phosphorus (P). Using the global equation of 
Gruber and Sarmiento [1997], N* is defined as

                       N*(µmol/kg) = 0.87(N - 16P + 2.90)                 (3)

Figure 5b shows the magnitude of the denitrification signal along the σθ = 
26.9-27.0 surface. The N* values were converted from nitrogen units to µmol C 
kg-1 based on a denitrification carbon to nitrogen ratio of 106:-104 [Gruber 
and Sarmiento, 1997]. Negative values reflect nitrogen fixation, while 
positive values indicate denitrification. As expected, the values of N* are 
essentially zero in the main Indian Ocean basin but show a strong 
denitrification signal at middepths in the Arabian Sea. The low N* values at 
the north end of this surface (Figure 5b) are from the Bay of Bengal and show 
little or no denitrification in this region. Subtracting a denitrification 
correction term from the original ∆C* equation lowers the high ∆C* values at 
the northern end of the section leaving the expected maximum near the outcrop 
region (Figure 5c).

The final definition for ∆C* as used in this work is given by (4)

                  ∆C* = TCO2^meas - TCO2^(S,T,Alk^0,280)
                      -(117/-170)(O2-O2^(sat))
                      -(1/2)(TA-ALK^0+(16/-170))O2-O2^(sat))
                      -(I06/-104)N*                                       (4)

where TC02(meas), TA, and O2 are the measured concentrations for a given 
water sample in µmol kg-1. Alk^0 is the preformed alkalinity value as 
described in section 2.3.1. 02^(sat) is the calculated oxygen saturation 
value that the waters would have if they were adiabatically raised to the 
surface. TCO2^(S,T,Alk^0,280) is the TC02 value the waters would have at the 
surface with a TA value equal to Alk^0 and ƒC02 value of 280 µatm.


2.3.3.  ESTIMATION OF AIR-SEA DISEQUILIBRIUM 

To isolate the anthropogenic CO2 component from ∆C*, the air-sea 
disequilibrium values (∆C(dis)) must be determined. Gruber et al. [1996] 
described two techniques for estimating these values on density surfaces. For 
deeper density surfaces one can assume that the waters far away from the 
outcrop region are free from anthropogenic CO2. The mean ∆C* values in these 
regions therefore reflect only the disequilibrium value. For shallower 
surfaces the air-sea disequilibrium can be inferred from the ∆C*I tracer.

∆C*(t) is the difference between C* and the concentration the waters would 
have in equilibrium with the atmosphere at the time they were last at the 
surface. The time since the waters were in contact with the surface is 
estimated from CFC-12 age (t) and the atmospheric CO2 concentration history 
as a function of time (ƒC02{t(sample)-t}). The atmospheric CO2 time history 
from 1750 through 1996 was determined from a spline fit to ice core and 
measured atmospheric values [Neftel et al., 1994; Keeling and Whorf, 1996]. 
The CFC-12-based ages were determined following the technique described by 
Warner et al. [1996]. The apparent age of the water is determined by matching 
the CFC-12 partial pressure (pCFC-12) of the waters with the atmospheric CFC-
12 concentration history (procedures and atmospheric time history provided by 
J. Bullister). Although CFCs do not give a perfect representation of the true 
calendar age of the waters, Doney et al. [1997] have shown that the CFC-12 
and 3H-3He ages in the North Atlantic agree within 1.7 years for ages less 
than 30 years. Gruber [1998] successfully used both CFC and 3H-3He ages for 
his disequilibrium calculations in the Atlantic and has thoroughly discussed 
the assumptions and caveats associated with these techniques. The disequilibrium 
values on shallow density surfaces presented here were calculated using CFC-12 
ages modified from the ∆C*(t) equation of Gruber [1998] to include the 
denitrification correction: 

       ∆C*(t) = TCO2^meas - TCO2^(S,T,Alk^0,ƒC02{t(sample)-t})
              -(117/-170)(O2-O2^(sat))
              -(1/2)(TA-ALK^0+(16/-170))O2-O2^(sat))
              -(I06/-104)N*                                               (5)

where TCO2^(S,T,Alk^0,ƒC02{t(sample)-t}) is the TC02 the waters would have at 
the surface with a TA value of Alk^0 and ƒC02 value in equilibrium with the 
atmospheric CO2 concentration at the time the waters were last at the surface 
(date of sample collection minus CFC age).

The CFC age method was used for waters with densities less than σθ = 27.25 and 
CFC-12 ages less than 40 years. The anthropogenic CO2 of the waters with 
pressures less than 150 dbars or densities less than σθ = 25.95 was determined 
by subtracting the ∆C*(t) value estimated at each sample location from the 
corresponding ∆C* value. Given that the Indian Ocean does not extend into the 
high northern latitudes, the major outcrop region for Indian Ocean waters 
below the mixed layer is toward the south. Although other tracers might be 
used to identify multiple end-members, the CFC-12 ages on each density 
surface get steadily older toward the north, and the ∆C*(t) values are 
reasonably constant (see diamonds in Figure 6). This suggests that most of 
the water in the Indian Ocean is derived from the south or, at least in terms 
of the air-sea disequilibria, cannot be distinguished from other sources. The 
∆C(dis) term for the main Indian Ocean basin therefore was determined from a 
mean ∆C*(t) value on each surface. The mean ∆C(dis) terms were then 
subtracted from the individual ∆C* values to determine the anthropogenic 
component. Table 2 summarizes the ∆C(dis) values for the density surfaces 
estimated exclusively from the ∆C*(t) method.

One major exception to the southern source waters is observed in the Arabian 
Sea. Although none of the surfaces with σθ values greater than 26.0 outcrop in 
the Arabian Sea, a number of higher density surfaces do outcrop in the Red 
Sea and Persian Gulf. These outcrops could provide pathways for the 
introduction of CFCs and anthropogenic CO2 into the northern Arabian Sea and 
could reset the disequilibria term. Wyrtki [1973] noted that the Red Sea and 
Persian Gulf waters mix in the Arabian Sea to form the high-salinity North 
Indian Intermediate Water (NIIW). The ∆C*(T) values in the Arabian Sea do 
vary significantly and generally have a strong correlation with salinity. The 
CFC-12 ages also begin to get younger toward the northern end of the Arabian 
Sea. These high salinity waters appear to have a higher disequilibria term 
than the lower-salinity waters that make up the majority of the Indian Ocean 
intermediate waters.

To account for this phenomenon, the Arabian Sea waters (north of 5°N and west 
of 78°E) were isolated, and the ∆C*(t) values were fit against salinity with 
a linear regression. Thus this region was treated as a two-end-member mixing 
scenario between the high salinity NIIW and the lower-salinity waters of the 
main Indian Ocean basin. The ∆C(dis) values in this region were determined 
based on the relative contributions of the two end-members using salinity as 
a conservative tracer. The coefficients for the Arabian Sea fits are given in 
Table 2. The difference between the high salinity and lower-salinity 
disequilibria generally decreased as densities increased (note decreasing 
slope values in Table 2) to the point where the Arabian Sea disequilibria 
values were no longer distinguishable from the main Indian Ocean basin 
values. The additional terms were dropped for surfaces where the two end 
member mixing terms resulted in values within the error of the basin-wide 
mean (Table 2).

As stated previously, the disequilibria term for the deeper, CFC free 
surfaces was determined directly from the mean ∆C* value of each density 
interval. Careful examination of the extent of CFC penetration along the 
density surface was used to limit data used in determining the ∆C(dis) term. 
Only regions where CFC concentrations were below a reasonable blank (0.005 
pmol kg-1) were considered. The ∆C(dis) values determined using this method 
are summarized in the lower half of Table 3 (σθ > 27.5).


FIGURE 5:  ∆C* values for data on the 26.9 - 27.0 σθ surface: 
           (a) calculated without denitrification, (b) denitri-
           fication signal put in terms of ∆C*, (c) with 
           denitrification correction (i.e., data in Figure 
           5a minus the data in Figure 5b).


Determination of the ∆C(dis) values for either shallow or deep surfaces is 
relatively straightforward using the techniques mentioned above. It is not 
straightforward, however, to estimate the ∆C(dis) values for intermediate 
levels where the CFC ages are relatively old and may be significantly 
influenced by mixing and yet the waters could have enough anthropogenic CO2 
to influence the estimates based on ∆C*. The effect of using the ∆C* 
technique in waters that actually have anthropogenic CO2 would be to 
overestimate the ∆C(dis) term and thus underestimate the anthropogenic CO2, 
The effect of mixing on the CFC ages, however, generally results in an 
underestimation of the CFC age which would lead to an underestimation of the 
∆C(dis) term and an overestimation of the anthropogenic CO2, The CFC age 
technique has additional problems in waters with σθ values greater than 27.25, 
because the waters with the younger ages are all found in the very high 
latitudes of the Southern Ocean and generally are not directly ventilated in 
these regions. Therefore the basic assumption that the ∆C(dis) term can be 
determined by following the density level to its outcrop and examining the 
younger waters there is not valid.


TABLE 2: Values of ∆C(dis) Determined on Potential Density (σθ) Intervals
_______________________________________________________________________

  Potential    Main Basin     Main       Arabian    Arabian  Arabian
   Density     Mean (SDM)    Basin #    Intercept    Slope    # of 
    Range                   of Points     (SD)       (SD)    Points
 -----------  ------------  ---------  ----------  --------  -------
 25.95-26.05   -1.3(±0.88)     56      -740(±92)   21.3(±3)  12
 26.05-26.15   -0.7(±1.21)     42      -745(±130)  21.4(±4)  12
 26.15-26.25   -3.4(±0.65)     63      -699(±76)   20.0(±2)  11
 26.25-26.35   -4.8(±0.62)     61      -516(±90)   14.8(±3)  12
 26.35-26.45   -5.6(±0.48)     83      -316(±84)    9.1(±2)  20
 26.45-26.55   -7.1(±0.34)    103      -558(±87)   15.9(±2)  21
 26.55-26.65   -7.2(±0.32)    123      -512(±53)   14.5(±I)  28
 26.65-26.75   -8.9(±0.27)    152      -397(±52)   11.2(±I)  34
 26.75-26.85   -9.1(±0.23)    254      -428(±66)   12.0(±2)  28
 26.85-26.95  -11.2(±0.31)    209      -285(±115)   7.9(±3)   6
 26.95-27.00  -12.2(±0.35)    104
 27.00-27.05  -13.8(±0.48)     92
 27.05-27.10  -15.2(±0.4O)     90
 27.10-27.15  -16.3(±0.47)     84
 27.15-27.20  -17.1(±0.51)     89
 27.20-27.25  -19.5(±0.56)     74
_______________________________________________________________________
 Standard deviations (SD) are given for the slope and intercept terms 
 for the Arabian Sea data. Standard deviation of the mean (SDM, i.e., 
 standard deviation weighted by the number of individual determinations) 
 is given for each main basin estimate.  Values of ∆C(dis) are given in 
 µmol kg-1. Dashes indicate value not determined.


TABLE 3: Values of ∆C(dis) Determined on Potential Density (σθ) Intervals
_________________________________________________________________________

  Potential     Mean ∆C*      # of     Mean ∆C*l     # of    Final Mean
   Density        (SDM)      Points      (SDM)      Points   ∆Cdi5(SDM)
    Range        
 -----------  ------------   ------   ------------  ------  ------------
 27.25-27.30   -2.3(±0.45)     42     -19.7(±0.98)    22    -8.3(±1.l3)
 27.30-27.35   -4.0(±0.49)     45     -21.0(±0.84)    19    -9.1(±1.06)
 27.35-27.40   -5.3(±0.44)     72     -22.5(±1.25)     7    -6.8(±0.69)
 27.40-27.45   -7.1(±0.26)     92     -23.5(±0.83)    10    -8.7(±0.54)
 27.45-27.50   -7.9(±0.30)     98     -25.0(±1.65)     7    -9.0(±0.51)
 27.50-27.55   -9.3(±0.28)     93                            -9.3(±0.28)
 27.55-27.60  -10.7(±0.28)     92                           -10.7(±0.28)
 27.60-27.65  -11.3(±0.34)    125                           -11.3(±0.34)
 27.65-27.70  -13.0(±0.36)    127                           -13.0(±0.36)
 27.70-27.75  -14.8(±0.30)    184                           -14.8(±0.30)
 27.75-27.80  -15.3(±0.24)    349                           -15.3(±0.24)
    >27.80    -18.6(±0.15)    629                           -18.6(±0.15)
_________________________________________________________________________
 Standard deviation of the mean given in brackets (SDM, i.e., standard 
 deviation weighted by the number of individual determinations). Values 
 of ∆C(dis) are given in µmol kg-l. Dashes indicate value not determined.


As a general rule, the errors associated with the CFC age technique increase 
at higher density levels, and the errors associated with the ∆C* technique 
decrease at higher density levels. To minimize the errors in the final 
∆C(dis) determination, waters with σθ values between 27.25 and 27.5 were 
evaluated using a combination of the two methods mentioned above. The 27.25 
cut in the CFC age technique was chosen because this density corresponds with 
the core of the Antarctic Intermediate water and also generally the highest-
density water that outcrops in this region [Wirtki, 1973; Levitus and Boyer, 
1994; Levitus et al., 1994]. To help ensure that the ∆C(dis) values were 
determined on waters moving into the main Indian Ocean basin, mean ∆C*(t) 
values were only estimated from samples north of 35°S with CFC-12 ages less 
than 40 years. Mean ∆C* values were also determined on the same density 
surfaces for samples where CFCs were measured, but concentrations were below 
0.005 pmol kg-1. The final mean value used for the ∆C(dis) correction on each 
surface was determined from the mean of the combined individual estimates 
from each method (Table 3).

Examination of the individual and combined means in Table 3 indicates that 
there is a sizeable spread in the estimates from the two techniques in the 
overlap region. This difference is maximized since these density levels are 
pushing the limits of both techniques, and the errors in both estimates serve 
to increase this difference. Since the number of points available from the 
CFC age technique generally decreased at greater density levels and the 
number of points from the ∆C* technique generally increased at greater 
density levels, the mean becomes progressively more heavily weighted toward 
the ∆C* technique as the density levels increased. Although this is not the 
ideal solution, we believe that this minimizes the potential errors as much 
as possible. The technique used to estimate final ∆C(dis) values in this 
region could systematically bias the anthropogenic CO2 inventory estimates. 
The magnitude of this potential error on the final inventory was estimated to 
be approximately ±1.8 Pg C by integrating the difference between the two 
methods over the effected water volume. This estimate represents a maximum 
potential error since the known limitations of each method work to increase 
the differences in ∆C(dis).


2.3.4.  TIME ADJUSTMENT FOR INDIGO DATA 

One difficulty with combining data from different cruises for a time-
dependent calculation like the anthropogenic CO2 inventory is the issue of 
getting the data sets referenced to a common time. One of the advantages of 
the WOCE/JGOFS Indian Ocean survey data is the fact that all of the samples 
were collected in a little over a year's time. In terms of the CO2 inventory 
this is essentially a synoptic data set. The couple of years between the 
CIVA-1 cruise and the WOCE/JGOFS data are also not distinguishable in terms 
of the anthropogenic increase. The INDIGO data, however, were collected 8-10 
years before the WOCE/JGOFS data set and must be adjusted to reflect the 
anthropogenic uptake during that time. Unfortunately, any correction of this 
sort can have large errors and potentially bias the results. This problem 
must be weighed against the errors of ignoring the time difference between 
cruises or omitting these data entirely. The decision to correct the INDIGO 
data was based on two factors. First, analysis of the change in anthropogenic 
inventory between GEOSECS and WOCE (discussed below) indicated that a 
significant fraction of the total anthropogenic uptake has occurred in the 
past 2 decades. Second, careful examination of objective maps of 
anthropogenic CO2 made prior to the INDIGO correction showed obvious, 
anomalously low concentrations in the regions strongly dependent on the 
INDIGO data. Two different adjustment functions were made depending on 
whether the stations were located in the main Indian Ocean basin or in the 
Southern Ocean.

North of 30°S, where portions of the INDIGO data were located relatively near 
WOCE stations, a crossover comparison of the INDIGO anthropogenic CO2 
concentrations as a function of density was made with the WOCE/JGOFS data in 
that region. The difference between the two data sets was evaluated at σθ 
intervals of 0.05 from the surface to σθ = 27.5 and added to the INDIGO data. 
This correction ranged from approximately 12 µmol kg-1 at the surface down to 
zero at 27.5.

South of 30°S, there were very few WOCE or CIVA-1 stations close enough for a 
proper crossover comparison. It was clear from the northern data, however, 
that some correction was necessary. Given that the isolines for most 
properties in the Southern Ocean run east-west, we decided to correct the 
southern INDIGO data based on a crossover comparison with all results from 
CIVA-1 and WOCE cruises in that region. The average adjustment for the 
southern stations was approximately 11 µmol kg-l over the same density range. 
The magnitude of the corrections in both regions is consistent with the 
expected increase over the time period between cruises.


2.3.5.  EVALUATION OF ERRORS 

Error evaluation is much more difficult for the ∆C* method than for the time 
series approach because of potential systematic errors associated with some 
of the parameters (Le., the biological correction). The random errors 
associated with the anthropogenic CO2 can be determined by propagating 
through the precision of the various measurements required for the 
calculation of (4). 

{σ(C(anth))}^2 = {σ(C)}^2 + {σ(C(eq))}^2

               + {(-R(CO) - 0.5R(NO))σ(O(2))}^2

               + {(R(CO) + 0.5R(NO))σ(O(2[sat]))}^2

                                     ∂C(eq)
               + {-0.5σ(TA)}^2 + {(- ------ + 0.5)σ(Alk^0)}^2
                                      ∂TA

               + {0.8667σ(N)}^2 + +{13.867σ(P)}^2

                              N-16P+2.9
               + {0.8667(-P - --------- )σ(R(N:P[nitr]))}^2
                                 120

               + {-0.00111(N - 16P + 2.9)σ(R(N:P[denitr]))}^2

               - {σ(∆C(dis))}^2                                           (6)

where 
      σ(C)         = 2 µmol kg-1 ;
      σ(C(eq))     = 4 µmol kg-1 ;
      σ(O(2))      = 1 µmol kg-1 ;
      σ(O(2[sat])) = 4 µmol kg-1 ;
      σ(TA)        = 4 µmol kg-1 ;

      ∂C(eq)
      -------      = 0.842 ;
      ∂TA

      σ(Alk^0)     = 7.8 µmol kg-1 ;
      σ(N)         = 0.2 µmol kg-1 ;
      σ(P)         = 0.02 µmol kg-1 ;
      σ(R(N:P[nitr])) = 0.25 ;
      σ(R(N:P[denitr])) = 15


The equation for the random error analysis is adapted from Gruber et al. 
[1996] (excluding those terms that involve the C:O Redfield error) with 
additional terms for the error propagation of the N* correction [Gruber and 
Sarmiento, 1997]. The terms involving the C:O are evaluated separately below 
because the random errors cannot be isolated from potential systematic 
errors. The sigma values used in (6) were either taken from the appropriate 
WOCE cruise reports or from previously determined estimates of Gruber et al. 
[1996] and Gruber and

Sarmiento [1997]. The error in the ∆C(dis) term is taken from the average 
value for the standard deviation of the mean for the examined surfaces 
(σ(∆C(dis)) = 0.5 µmol kg-1). The formulation given in (6) results in an 
estimated error of 6.1 µmol kg-1. This estimate is larger than the standard 
deviation of the ∆C* values below the deepest anthropogenic CO2 penetration 
depth (±2.8 µmol kg-1 for pressure > 2000 dbars) suggesting that the 
propagated errors may be a maximum estimate of the random variability.

The potential systematic errors associated with the anthropogenic CO2 
calculation are much more difficult to evaluate. The random error estimate 
above includes all terms except those associated with the C:O biological 
correction. Although other terms involving N:O and N:P corrections 
potentially have systematic offsets associated with errors in the ratio 
estimates, the only potentially significant errors involve the C:O 
corrections [Gruber et al., 1996; Gruber, 1998].

There is evidence, however, that the Anderson and Sarmiento [1994] 
stoichiometric ratios must be reasonably close to the actual remineralization 
ratios observed in the Indian Ocean. Figure 6 is a plot of ∆C*t based on CFC-
12 ages for the density interval from σθ = 27.1 to σθ = 27.15. The diamonds 
are the values calculated from (5). These values represent the preserved air-
sea disequilibrium value for the past 40 years and should be constant if the 
air-sea disequilibrium has not changed over time (Le., that the surface ocean 
CO2 is increasing at the same rate at the atmosphere). A linear regression of 
the diamonds in Figure 6 yields a slope that is not significantly different 
from zero. The circles and pluses are the ∆C*t values one would get by using 
a C:O ratio of -0.60 and -0.78 in (5), respectively. These C:O values 
represent one standard deviation from the Anderson and Sarmiento [1994] mean 
value of 0.69. The -0.60 ratio results in values with a significant positive 
slope. This slope would imply that the surface ocean CO2 is increasing much 
slower than the atmospheric increase. While this is possible, the -0.60 ratio 
is much larger than historical Redfield estimates and would be very difficult 
to justify. The -0.78 ratio is more typical of historical estimates but 
results in a significant negative slope in the ∆C*t values with time. A 
negative slope would imply that carbon is accumulating in the ocean faster 
than the atmosphere. Neither of these scenarios seems very likely. The fact 
that none of the ∆C*t values on the examined surfaces exhibit a statistically 
significant slope suggests that the C:O value of -0.69 does accurately 
represent the remineralization ratio for these waters and supports the 
methodology of taking a mean value of ∆C*t on these density surfaces.


FIGURE 6:  Plot of ∆C*t based on CFC-12 ages for the density 
           interval from σθ =27.1 to 27.15 versus CFC-12 age. 
           The diamonds were calculated using the Anderson 
           and Sarmiento [1994] c:o (-0.69). The circles and 
           pluses were calculated from C:O of -0.60 and -0.78, 
           respectively. Lines and text give results from a 
           linear regression of the three sets of data.


A sensitivity study was also used to evaluate the potential error associated 
with an incorrect C:O value. Two additional estimates of anthropogenic CO2 
were determined using the -0.60 and -0.78 C:O values. Since the C:O 
correction applies to both ∆C* and the ∆C*(t) terms, the disequilibrium 
values were reevaluated in the same manner as described above. The range of 
anthropogenic values from these three estimates varied as a function of 
apparent oxygen utilization (AOU) from 0.0 to 22 with an average difference 
of only 4.2 µmol kg-1. Because the C:O correction affects both the ∆C* and 
∆C*(t) terms together, much of the systematic error in the final 
anthropogenic estimate (∆C*-∆C*(t)) cancels out.


2.4. INVENTORY ESTIMATES

Basin-wide anthropogenic and excess CO2 concentrations (WOCE/JGOFS - GEOSECS) 
were evaluated on a 1° grid at 100 m intervals between the surface and 2600 m 
using the objective mapping techniques of Sarmiento et al. [1982]. Total 
anthropogenic CO2 was mapped over an area from 20° to 120°E and 70°S to 30°N 
(excluding areas of land, the Red Sea, the Persian Gulf, and the South China 
Sea). Because the WOCE/JGOFS data set did not cover much of the Southern 
Ocean, the excess CO2 maps were limited to the area north of 35°S. The values 
at each level were multiplied by the volume of water in the 100 m slab and 
summed to generate the total anthropogenic or excess CO2 inventory. The 
method of integrating mapped surfaces compared very well with the technique 
of vertically integrating each station and mapping the station integrals.

It is extremely difficult to evaluate a reasonable estimate of the potential 
errors associated with the inventory estimates. A simple propagation of 
errors implies that the random errors associated with any individual 
anthropogenic estimate is approximately ±6.1 µmol kg-1, but these errors 
should essentially cancel out for an integrated inventory based on nearly 
25,000 individual estimates. Systematic errors have by far the largest impact 
on the inventory estimates. Potential errors as large as ±1.8 Pg C have been 
estimated for the ∆C(dis) term. Sensitivity studies with the C:O variations 
give a range of total inventory estimates of ±2.5 Pg C. Other systematic 
errors could also be generated from the denitrification term, the terms 
involving N:0, the time correction for the INDIGO data, and the mapping 
routines used in the inventory estimates. The magnitude of these errors is 
believed to be much smaller than the uncertainty in either the C:O correction 
or the ∆C(dis) determination. Propagation of the two estimated uncertainties 
gives an overall error of approximately ±3 Pg C for the total inventory. An 
error of roughly 15% is comparable to previous error estimates using this 
technique [Gruber et al., 1996; Gruber, 1998]. Errors for regional 
inventories are assumed to scale to the total.



3. RESULTS AND DISCUSSION

The excess CO2 concentrations for the Indian Ocean range from 0 to 25 µmol 
kg-1. The most prominent feature in the excess CO2distribution, as shown with 
representative sections in the eastern and western Indian Ocean (Figure 7), 
is the maximum in concentrations at midlatitudes (~40°S). This maximum is 
coincident with the relatively strong gradient in surface density associated 
with the Subtropical Convergence and the transition from the high salinity 
subtropical gyre waters to the low-salinity Antarctic waters. The outcropping 
of these density surfaces and subsequent sinking of surface waters provides a 
pathway for excess CO2 to enter the interior of the ocean. Relatively high 
excess CO2 concentrations can also be observed at the very northern end of 
the western section (Figure 7a). Although not readily evident from this 
section, the distribution of concentration gradients indicates that excess 
CO2 is entering the northern Indian Ocean from the Persian Gulf and Red Sea 
regions. This is likely to result from the outcropping of density surfaces in 
these areas which are not ventilated in the main Indian Ocean basin. The 
implied Red Sea and Persian Gulf sources of CO2 are consistent with uptake 
estimates of anthropogenic CO2 in these areas as observed by Papaud and 
Poisson [1986]. The third major feature observed in the excess CO2 
distribution is a dramatic shoaling of the excess CO2 isolines south of 
approximately 40°S. Poisson and Chen [1987] attributed the low anthropogenic 
CO2 concentrations in Antarctic Bottom Water to a combination of the pack sea 
ice blocking air-sea gas exchange and the upwelling of old Weddell Deep 
Water. This explanation is consistent with the observed excess CO2 
distributions in this study.

The general features observed with excess CO2 are also observed in the 
anthropogenic CO2 distribution (Figure 8). The range of values, however, 
extends up to 55 µmol kg-1. The maximum depth of the 5 µmol kg-1 contour is 
approximately 1300 m at around 40°S, only 200 m deeper than the maximum depth 
of the 5 µmol kg-1 contour of excess CO2, The similarity in maximum 
penetration depth between the 200 year and the 18 year anthropogenic CO2 
accumulation, together with the wide range of depths covered by the 5 µmol 
kg-1 isoline, indicates that the primary pathway for CO2 to enter the ocean's 
interior is from movement along isopycnals, not simple diffusion or cross 
isopycnal mixing from the surface. The 1300 m penetration results from the 
downwarping of the isopycnals in the region of the Subtropical Convergence. 
Likewise, the low anthropogenic CO2 concentrations in the high-latitude 
Southern Ocean result from the compression and shoaling of isopycnal surfaces 
in that region. Although the complex oceanography of the Southern Ocean may 
call into question some of the assumptions regarding mixing and nutrient 
uptake ratios with these techniques, both the time series excess CO2 and the 
∆C* anthropogenic CO2calculations clearly indicate that the anthropogenic CO2 
concentrations south of approximately 50°S are relatively small.

The distribution of anthropogenic CO2 determined in this study is similar to 
the distribution presented by Chen and Chen [1989] based on GEOSECS and 
INDIGO data. Although the penetration depth at 40°S was slightly deeper than 
observed with this study (1400-1600 m for the 5 µmol kg-1 isoline), Chen and 
Chen also observed a significant shoaling of the anthropogenic CO2 isolines 
toward the south. They suggest that anthropogenic CO2 has only penetrated a 
few hundred meters into the high-latitude (>50°S) Southern Ocean.

There has been debate in the literature over recent years as to the 
importance of the Southern Ocean as a sink for anthropogenic CO2 [e.g., 
Sarmiento and Sundquist, 1992; Keeling et al., 1989; Tans et al., 1990]. Most 
of the recent data-based estimates, however, indicate a relatively small 
Southern Ocean sink [Poisson and Chen, 1987; Murphy et al., 1991; Gruber, 
1998; this study]. The lack of observed anthropogenic CO2 in the Southern 
Ocean is also qualitatively consistent with ∆14C estimates which show no 
measurable storage of bomb 14C in the Southern Ocean since GEOSECS [Leboucher 
et al., 1998; R. Key, unpublished data, 1998]. Recent studies by Bullister et 
al. [1998], which show evidence of deep CFC penetration in the Southern 
Ocean, may appear to contradict these low anthropogenic CO2 estimates, but we 
believe it is further evidence that one must be careful when inferring 
anthropogenic carbon distributions from other tracers. One possible 
explanation of this apparent discrepancy may be the CFC equilibration rate of 
days which is significantly faster than the CO2 equilibration time of months 
[e.g., England, 1995; Warner and Weiss, 1985; Tans et al., 1990]. This can 
become an issue in the Southern Ocean where upwelling and convection may 
allow the CFCs to equilibrate to a greater extent than the CO2, Again, we 
acknowledge the limitations of the methods used in the Southern Ocean, and it 
is possible that the apparent discrepancy in the CFC penetration versus the 
CO2 penetration may also be an issue of detection limits. With a detection 
limit that is approximately 6 µmol kg-1, it is not possible to say with this 
technique that the concentration of anthropogenic CO2 below 500 m at 60°S is 
zero. However, we can say with some confidence that the concentration is not 
10 µmol kg-1 or greater. Since there is no natural oceanic source of CFCs and 
these compounds are not biologically utilized, the ability to detect them is 
much greater. If mixing has diluted the anthropogenic signal to 
concentrations just below detection limits, it is possible that carbon 
measurement based techniques would underestimate the Southern Ocean sink.


FIGURE 7:  Sections of excess CO2 along (a) -57°E and (b) -92°E. 
           Dots indicate sample locations used in sections.  Note 
           that I6S data along 30°E were brought into the line of 
           section for contours south of 40°S in Figure 7a.


The total anthropogenic CO2 inventory for the main Indian Ocean basin (north 
of 35°S) was 13.6±2 Pg C in 1995. The increase in CO2 inventory since GEOSECS 
was 4.1±1 Pg C for the same area. This represents a nearly 30% increase in 
the past 18 years relative to the total accumulation since pre-industrial 
times. The relative oceanic increase is very similar to the 31% increase 
observed in atmospheric concentrations over the same time period [Keeling and 
Whorf, 1996]. This similarity suggests that the oceans, at least for now, are 
keeping pace with the rise in atmospheric CO2, Approximately 6.7±1 Pg C are 
stored in the Indian sector of the Southern Ocean giving a total Indian Ocean 
inventory (between 20° and 120°E) of 20.3±3 Pg C in 1995.

To put these results in a global perspective, the total inventory for the 
Indian Ocean is only half that of the Atlantic (40±6 Pg C [Gruber, 1998]), 
but it contains an ocean volume that is nearly 80% of the Atlantic. The main 
difference between the two oceans, of course, is that the Indian Ocean does 
not have the high northern latitude sink that the Atlantic has. The big 
unknown at this point is the anthropogenic inventory of the Pacific. With 
nearly 50% of the total ocean volume the Pacific has the potential to be the 
largest oceanic reservoir for anthropogenic CO2.



4. COMPARISON WITH PRINCETON OCEAN BIOGEOCHEMISTRY MODEL

Current IPCC anthropogenic estimates are primarily based on global carbon 
models. Ultimately, these models are necessary to predict the oceanic 
response to future climate scenarios. It is important, however, to validate 
these models. One way to compare results is to examine profiles of the 
average anthropogenic concentrations such as those shown in Figure 9. The 
model presented here is the Princeton Ocean Biogeochemistry Model (OBM). The 
Princeton OBM is based on the circulation of Toggweiler et al. [1989] with 
explicit parameterization for the biological and solubility carbon pumps 
[Sarmiento et al., 1995; Murnane et al., 1998]. On this scale the model-based 
concentrations for both the total anthropogenic CO2 and the increase since 
GEOSECS appear to be reasonably consistent with the data. The primary 
difference is slightly higher values at middepths in the data-based 
estimates. A more detailed examination, however, indicates that the regional 
distribution of the model-based estimates is significantly different than the 
data-based distribution. Figure 10 presents maps of the vertically integrated 
excess CO2 normalized to a unit area. The model shows a consistent decrease 
in column inventory toward the north. The lowest inventories in the data-
based map are in a narrow band just south of the equator. The highest values 
are found in the southeastern Indian Ocean. Relatively high values are also 
observed in the Arabian Sea in the regions near the Red Sea and the Persian 
Gulf. The small patch of lower values immediately outside the Gulf of Aden 
does not result from low concentrations but rather results from the shallow 
water depth associated with the mid-ocean ridge in that area. The low values 
east of there, however, do result from lower concentrations near the southern 
tip of India. The total model-based inventory for the region north of 35°S is 
approximately 0.61 times the data-based inventory (Table 4). 


FIGURE 8:  Sections of anthropogenic CO2 along (a) -57°E and 
           (b) -92°E. Dots indicate sample locations used in sections.

FIGURE 9:  Profile of area weighted mean anthropogenic CO2 
           concentrations for model (solid symbols) and 
           data-based (open symbols) estimates for main 
           Indian Ocean basin (north of 35°S). Circles 
           show increase since GEOSECS (1978-1995). Triangles 
           show total increase since pre-industrial times.


Figure II shows maps of total anthropogenic CO2 column inventory. As with the 
excess CO2, the model predicts decreasing anthropogenic concentrations north 
of 35°S. The data-based distribution pattern is similar to the data-based 
excess C02 pattern with a minimum inventory band south of the equator and 
higher values toward the north and south. Similar to the findings with excess 
CO2, the model-based anthropogenic inventory north of 35°S is approximately 
0.68 times the data-based inventory (Table 4). The largest difference between 
the data-based results and the model is evident, however, in the Southern 
Ocean (south of 35°S). In this region the model anthropogenic inventory is 
nearly 2.6 times the data-based inventory (Table 4). The primary reason for 
this difference is the presence of a large convective cell in the model at 
approximately 55°S and 90°E in the Southern Ocean. This is a region of 
intense, unrealistic convection which pumps relatively high concentrations of 
anthropogenic CO2 down in excess of 4000 m. This problem is a known 
shortcoming with the mixing scheme used in several GCMs [e.g., England, 1995] 
but has never before been quantified in terms of its direct effect on 
anthropogenic CO2 storage by the models. It is beyond the scope of this paper 
to examine the details of the model physics; however, this same general trend 
of getting too much anthropogenic CO2 into the Southern Ocean has been 
observed in comparisons with three other global carbon models with a range of 
mixing and advective schemes [C. Sabine, unpublished results, 1998]. This 
cursory comparison with the Princeton OBM clearly demonstrates the diagnostic 
usefulness of comparing the data distributions with models.



5. CONCLUSIONS

Although the general techniques proposed by Gruber et al. [1996] and Wallace 
[1995] can be important tools for estimating global anthropogenic CO2, 
careful consideration must be used when applying these techniques to new 
regions. Complicating factors such as those found in the Arabian Sea can 
influence the quality of the estimates if not properly addressed. An 
additional term had to be added to the basic ∆C* calculation to account for 
denitrification in the Arabian basin. For the excess CO2 calculations a 
categorical variable was used to remove regional biases in the GEOSECS fit.

With the above mentioned modifications the anthropogenic inventory of the 
Indian Ocean was shown to be relatively small, approximately half of that 
found in the Atlantic. This study provides an important baseline for future 
studies of the Indian Ocean. The calculations presented here suggest that the 
oceanic increase in carbon storage (30%) has roughly kept pace with the 
atmosspheric increase (31%) over the past 18 years. Models predict that this 
trend is likely to change as atmospheric CO2 concentrations continue to rise 
in the future [Sarmiento et al., 1995]. As more CO2 enters the ocean, the 
carbonate ion concentration will become depleted. This will decrease the 
buffering capacity of the ocean and its ability to continue carbon uptake at 
the current rate. Comparison of future survey cruises in the Indian Ocean 
with the anthropogenic and total carbon values from this study will allow us 
to document future changes in ocean chemistry and better understand the 
oceanic response to global change. 


FIGURE 10: Maps of vertically integrated excess CO2 based on 
           (a) data and (b) model estimates. Contours are in mol 
           m^-2. Solid regions indicate land mask used for inventory 
           estimates. Thin lines in Figure 10b indicate land regions 
           used in Figure 10a.


TABLE 4: Summary of Data Based and Model Based Inventory Estimates
         ______________________________________________________________

                   Total    Southern  Main Basin  Main Basin  Increase
                   Anthro-  Ocean     Anthro-     Excess      since
                   pogenic  Anthro-   pogenic     CO2(χ)      GEOSECS
                   CO2(α)   pogenic   CO2(χ)      PgC         %
                   PgC      CO2(β)    PgC
                            PgC
                   -------  --------  ----------  ----------  --------
          Data     20.3±3     6.7±1     13.6±2      4.1±1       29.9
          based
          
          Model     26.7      17.4       9.3         2.5        26.7
          based
         ______________________________________________________________
          (α) Area between 20°-120°E.
          (β) Latitude is < 35°S.
          (χ) Latitude is > 35°S.


Finally, comparison of the spatial distribution of the anthropogenic
carbon can be a powerful tool for understanding the carbon
uptake of the models. The methods presented here provide a two point
calibration for examining the response of the models to
observed atmospheric CO2 increases. The anthropogenic CO2 data
can also be subtracted from the TC02 measurements to provide an
estimate of the pre-industrial TC02 distribution. Comparing these
estimates with the steady state model distributions can provide
insight into whether differences in the model and data-based
anthropogenic inventories result from problems with the uptake
parameterization or the basic physics and initialization parameters
of the model. This paper is just the first step in the interpretation of
the WOCE/JGOFS data set. Subsequent papers will analyze additional
cruise data as they become available. Together. these analyses
will significantly improve our understanding of the global
carbon cycle.


FIGURE 11: Maps of vertically integrated anthropogenic CO2 
           based on (a) data and (b) model estimates. Contours 
           are in mol m-2. Solid regions indicate land mask 
           used for inventory estimates. Thin lines in Figure 
           11b indicate land regions used in Figure 1la.



ACKNOWLEDGMENTS. 

This work was accomplished with the cooperative efforts of the DOE CO2 
Science Team. We thank B. Warren for organizing the WOCE Indian Ocean 
expedition, the captain and crew of the R/V Knorr, and the WOCE-HP personnel 
at sea. We. thank the chief scientists (M. McCartney, A. Gordon, L. Talley, 
W. Nowlin, J. Toole, D. Olson, J. Morrison, N. Bray, and G Johnson) and the 
CFC PIs (1. Bullister, R Fine, M. Warner, and R Weiss) for giving us access 
to their preliminary data for use in this publication. We also thank N. 
Metzl, G Eischeid, and C. Goyet for providing carbon data and T. Takahashi 
for providing S4I data and ∆pC02 maps. We thank R Murnane and T. Hughes for 
providing model results. Strong collaboration, cooperation, and input from N. 
Gruber and investigators in the NOAA Ocean Atmosphere Carbon Exchange Study 
(R Wanninkhof, R. Feely, J. Bullister, and T.-H. Peng) is also acknowledged 
along with the helpful comments of two anonymous reviewers. This work was 
primarily funded by DOE grant DE-FG02-93ER61540 with additional support by 
NSF/NOAA grant OCE-9120306. 



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________________


   K.M. Johnson, Oceanographic and Atmospheric Sciences Division,
Brookhaven National Laboratory, Upton, NY 11973.

   RM. Key, C.L. Sabine, and J.L. Sarmiento, Department of Geosciences,
Princeton University, Princeton, NJ 08544. (key@geo.princeton.edu,
sabine@geo.princeton.edu, andjls@splash.princeton.edu)

   F.J. Millero, Rosenstiel School of Marine and Atmospheric Sciences,
University of Miami, 4600 Rickenbacker Cswy., Miami, FL 33149.
(fmillero@rsmas.miami.edu)

   A. Poisson, Laboratoire de Physique et Chimie Marines, Universite
Pierre et Marie Curie, 4 Place Jussieu, Tour 24-25, 75720 Paris Cedex 05
France. (apoisson@ccr.jussieu.fr)

   D.W.R. Wallace, Abteilung Meereschemie, Institut fur Meereskunde an
der Universität Kiel, Duesternbrooker Weg 20, D-24105 Kiel, Germany.
(dwallace@ifm.uni-kieI.de)

   C.D. Winn, Marine Science Program, Hawaii Pacific University, 45045
Kamehameha Highway, Kaneohe, HI 96744-5297.
(cwinn@soest.hawaii.edu)



(Received May 11, 1998; revised November 24,1998; accepted November 24,1998.)









                                  APPENDIX E:

                        REPRINT OF PERTINENT LITERATURE




Key R. M., and P. D. Quay. 2002. U.S. WOCE Indian Ocean Survey: Final Report 
for Radiocarbon.  Technical Report. Princeton University, Princeton, N.J.





                         U.S. Woce Indian Ocean Survey:
                          Final Report for Radiocarbon 

                         Robert M. Key and Paul D. Quay

                 Ocean Tracer Laboratory; Technical Report 02-1
                                 July 12, 2002



1.0  General Information 


The U.S. WOCE Indian Ocean Survey consisted of 9 cruises covering the period 
December 1, 1994 to January 22, 1996.  All of the cruises used the R/V Knorr 
operated by the Woods Hole Oceanographic Institute.  A total of 1244
hydrographic stations were occupied with radiocarbon sampling on 366 stations. 
The radiocarbon stations are shown as black dots in Figure 1.  To give an 
indication of the total radiocarbon coverage for the Indian Ocean, the figure 
includes radiocarbon stations from WOCE sections S4I (Key, 1999; red dots) and 
I6S (Leboucher, et al., 1999; white dots) and from the earlier GEOSECS (Stuiver 
and Ostlund, 1983; brown dots) and INDIGO (Bard, et al., 1988; yellow dots) 
expeditions.  Specific summary information on the 9 WOCE survey cruises is given 
in Table 1. 


TABLE 1: Summary for Survey Sections 
         __________________________________________________________________

                      Chief                               ∆14C     ∆14C
          Cruise    Scientist     Start       End       Stations  Samples  
          ------  ------------  ----------  ----------  --------  --------
          I8SI9S  M. McCartney  12/01/94    01/19/95       26       662  
                  T. Whitworth  Fremantle   Fremantle 
                                Australia   Australia      
          I9N     A. Gordon     01/24/95    03/05/95       22       364  
                  D. Olson      Fremantle   Colombo 
                                Australia   Sri Lanka      
          I8NI5E  L. Talley     03/10/95    04/15/95       20       414
                  M. Baringer   Colombo     Fremantle 
                                Sri Lanka   Australia       
          I3      W. Nowlin     04/20/95    06/07/95       20       462
                  B. Warren     Fremantle   Port Louis
                                Australia   Mauritius       
          I5WI4   J. Toole      06/11/95    07/11/95       15       361 
                                Port Louis  Port Louis
                                Mauritius   Mauritius      
          I7N     D. Olson      07/15/95    08/24/95       22       373 
                  S. Doney      Port Louis  Muscat 
                  D. Musgrave   Mauritius   Oman   
          I1      J. Morrison   08/29/95    10/16/95       24       426 
                  H. Bryden     Muscat      Singapore      
                                Oman        China       
          I10     N. Bray       11/11/95    11/28/95        6       127  
                  J. Toole      Dampier     Singapore      
                                Australia   China      
          I2      G. Johnson    12/02/95    01/22/96       28       651 
                  B. Warren     Singapore   Mombasa 
                                China       Kenya   
         __________________________________________________________________



2.0 Personnel 

∆14C sampling for cruise I8SI9S was carried out by Melinda Brockington 
(University of Washington). Personnel for the remainder of the cruises came from 
the Ocean Tracer Lab (OTL Princeton University) and included G. McDonald, A. 
Doerty, R. Key, T. Key, and R. Rotter. ∆14C (and accompanying δ13C) analyses 
were performed at the National Ocean Sciences AMS Facility (NOSAMS) at Woods 
Hole Oceanographic Institution. R. Key collected the data from NOSAMS, merged 
the files with hydrographic data, assigned quality control flags to the ∆14C 
and submitted the results to the WOCE office (4/02).  R. Key is P.I. for the 14C 
data.  P. Quay (U.W.) and A. McNichol (WHOI/NOSAMS) are P.I.s for the 13C data. 
In addition to collecting samples the shipboard 14C person was also responsible 
for operation of the underway pCO2 system provided by the OTL (Sabine and Key, 
1997; Sabine, et al., 2000). 


3.0 Results 


This ∆14C data set and any changes or additions supersedes any prior release. 


3.1 Hydrography 

Hydrographic data from these cruises were submitted to the WOCE office by the 
chief scientists and are described in various reports which are available from 
the web site (http://whpo.ucsd.edu/data/tables/onetime/1tim_ind.htm). 

3.2 

∆14C The ∆14C values described here were originally distributed in the NOSAMS 
data reports listed in Table 2 and given in full in the References.  Those 
reports included results which had not been through the WOCE quality control 
procedures.  For WOCE applications, this report supersedes the NOSAMS reports. 


TABLE 2: NOSAMS Data Report Summary 
                               _________________

                                Cruise   Report
                                -------  ------
                                I8SI9S   99-089  
                                I7NI9N   99-144  
                                I1       99-199  
                                I8N      00-218  
                                I3I5WI4  01-013  
                                I2       02-001  
                               _________________

All of the AMS samples from these cruise have been measured using the AMS 
methods outlined in Key et al., 1996 and citations therein (especially Mcnichol 
et al., 1994; Osborne et al. 1994; and Scheideret al. 1995).  Table 3 summarizes 
the number of samples analyzed and the quality control flags assigned for each 
cruise.  Approximately 98% of the samples collected were deemed to be "good" 
(flagged 2 or 6).  Quality flag values were assigned to all ∆14C measurements 
using the code defined in Table 0.2 of WHP Office Report WHPO 91-1 Rev. 2 
section 4.5.2. (Joyce, et al., 1994).  No measured values have been removed from 
this data set. 


TABLE 3: Sample Analysis and QC Summary 
                   _______________________________________

                            Samples     QC Flag Totals  
                    Cruise  Analyzed  2    3   4   5   6  
                    ------  -------- ---  --- --- --- ---
                    I8SI9S    662    636   6   8   0  12
                    I9N       368    354   4   3   4   3  
                    I8NI5E    416    401   6   0   2   7  
                    I3        463    448   5   0   1   9  
                    I5WI4     366    342   3   1   5  15  
                    I7N       383    370   3   0  10   0  
                    I1        430    421   2   2   4   1  
                    I10       127    127   0   0   0   0  
                    I2        655    636  13   2   4   0  
                    Total    3870   3735  42  16  30  47  
                   _______________________________________



4.0 Data Summary 

Figures 2-6 summarize the ∆14C data collected during the Indian Ocean survey. 
Only ∆14C measurements with a quality flag value of 2 ("good") or 6 
("replicate") are included in the figures.  Figure 2 shows the ∆14C values with 
2σ error bars plotted as a function of pressure.  The mid depth ∆14C minimum 
which occurs around 2500 meters in the Pacific is not apparent in these data.
In fact, there is very little variation in the deep and bottom water other than 
the previously reported decrease in ∆14C from south to north. All of the 
samples collected at a depth greater than 1000 meters have a mean ∆14C = 
-165.±25‰ (standard error = 0.5‰ with n=2086).  A substantial fraction of this 
variability is due to the difference between the Southern Ocean and main basin 
deep waters. 

Figure 3 shows the deep (>1000m) ∆14C values plotted against silicate.  The 
black and red points are from north and south of 35°S, respectively.  The 
straight line shown in the figure is the least squares regression relationship 
derived by Broecker et al. (1995) based on the GEOSECS global data set. 
According to their analysis, this line (∆14C = -70 - Si) represents the 
relationship between naturally occurring radiocarbon and silicate for most of 
the ocean.  They noted that the technique could not be simply applied at high 
latitudes as confirmed by this data set. 

Figure 4 shows all of the radiocarbon values plotted against potential 
alkalinity (defined as [alkalinity + nitrate]*35/salinity).  The straight line 
is the regression fit (14C = -59 -0.962(PALK-2320) derived by Rubin and Key 
(2002) using GEOSECS measurements assumed to have no bomb-produced ∆14C.  The 
value 2320 is the estimated surface ocean mean potential alkalinity.  As with 
Figure 3 the black and red points in Figure 4 indicate measurements taken north 
and south of 35°S, respectively. Unlike the silicate plot (Figure 3), there is 
no apparent difference in the relationship for Southern Ocean vs Indian Ocean 
deep waters.  The distance a point falls above the regression line is an 
estimate of the bomb radiocarbon contamination for the sample. 

Figures 5-9 show gridded sections of the ∆14C data. In each figure the water 
column is divided into upper (0-1000m) and lower (1000-bottom) portions.  The 
data were gridded using the loess method (Chambers et al., 1983; Chambers and 
Hastie, 1991; Cleveland,1979; Cleveland and Devlin, 1988).  The span for the 
fits was adjusted to be minimum and yet capture the large scale features.  The 
contour interval is 10‰ for the upper water column and 20‰ for intermediate and deep water. 

Figure 5 and Figure 6 show the meridional ∆14C distribution in the eastern and 
western Indian Ocean.  In both figures the distribution pattern is very similar 
to that seen in the Pacific Ocean WOCE samples.  In the Pacific the maximum 
∆14C values were frequently found in shallow water, but beneath the surface.  
In the Indian Ocean data a subsurface maximum is not so common.  Both sections 
show intrusion of Circumpolar Deep Water from the south along the bottom and 
return flow of deep water at 2000-3000m.  As with the Pacifiic the middepth 
waters have the lowest ∆14C values, however the middepth Indian Ocean waters 
have significantly higher values that corresponding Pacific waters.  This 
pattern is consistent with a mean ageing of waters from the Atlantic to Indian 
to Pacific. 

Figure 7, Figure 8 and Figure 9 show zonal ∆14C sections along the WOCE lines 
I1 (~10°N), I2(~8°S) and I3(~20°S).  Except for the western ends, the ∆14C 
contours in the upper kilometer are relatively flat.  In each section the deep 
waters of the western basins have somewhat higher ∆14C than at the same depth 
in the eastern basins.  The strength of this signal decreases from south to 
north and is almost certainly due to the western basins having a higher fraction 
of North Atlantic Deep Water. 

Figure 10 shows the meridional distribution of bomb produced ∆14C (via Rubin 
and Key, 2002) in the eastern and western Indian Ocean.  The eastern section 
used all WOCE samples collected at depths less than 1000m and east of 85°E.  The 
western section uses the same depth range, but samples from west of 75°E.  Both 
sections are contoured and colored in potential density space rather against 
depth.  One might expect a priori that the distributions would differ north of 
the equator due to the geography and difference in chemistry between the Bay of 
Bengal and Arabian Sea.  Perhaps unexpected is the fact that the distributions 
differ significantly as far as 40°S.  In the eastern section the maximum bomb 
∆14C values are found between 40°S and 20°S and more or less uniformly from the 
surface down to the level where σθ~26.5.  The western section has a maximum in 
the same latitude range but in this case the maximum occurs as a subsurface 
lens. 


Figure  1: AMS 14C station map for WOCE S4I. 
Figure  2: ∆14C results shown with 2σ error bars. 
Figure  3: ∆14C as a function of silicate for samples collected deeper than 
           1000m.  The black points are from north of 35°S and the red points 
           south of 35°.  The straight line shows the relationship proposed by 
           Broecker, et al., 1995 (∆14C = -70 - Si with radiocarbon in ‰ and 
           silicate in µmol/kg). 
Figure  4: Based on the potential alkalinity method (Rubin and Key, 2002), the 
           samples which plot above the line and have potential alkalinity 
           values less than about 2400 µmole/kg are contaminated with bomb-
           produced 14C. 
Figure  5: ∆14C, along I8S and I9N in the eastern Indian Ocean. 
Figure  6: ∆14C along I7 in the western Indian Ocean. 
Figure  7: ∆14C along I1 in the northern Indian Ocean. 
Figure  8: ∆14C along I2 in the southern tropical Indian Ocean. 
Figure  9: ∆14C along I3 in the southern subtropical Indian Ocean at 
           approximately 20°S. . 
Figure 10: Mean bomb-produced ∆14C sections in the eastern (A) and western 
           (B) Indian Ocean, shown in potential density space for samples from 
           the upper 1000m. 
Figure 11: (A) ∆14C and (B) bomb-produced ∆14C for the surface Indian Ocean 
           from WOCE measurements. 
Figure 12: (A) ∆14C and (B) bomb-produced ∆14C on σθ=24.0. 
Figure 13: (A) ∆14C and (B) bomb-produced ∆14C on σθ=25.0 
Figure 14: (A) ∆14C and (B) bomb-produced ∆14C on σθ=26.0 
Figure 15: (A) ∆14C and (B) bomb-produced ∆14C on σθ=26.5 
Figure 16: (A) ∆14C and (B) bomb-produced ∆14C on σθ=26.8 
Figure 17: (A) ∆14C and bomb-produced (B) ∆14C on σθ=27.1 



5.0 REFERENCES AND SUPPORTING DOCUMENTATION 


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Chambers, J.M. and Hastie, T.J., 1991, Statistical Models in S, Wadsworth & 
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Chambers, J.M., Cleveland, W.S., Kleiner, B., and Tukey, P.A., 1983, Graphical 
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Cleveland, W.S. and S.J. Devlin, 1988, Locally-weighted regression: An approach 
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Elder, K.L., A.P. McNichol and A.R. Gagnon, Reproducibility of seawater, 
    inorganic and organic carbon 14C results at NOSAMS, Radiocarbon, 40(1), 
    223-230, 1998 

Joyce, T., and Corry, C., eds., Corry, C., Dessier, A., Dickson, A., Joyce, T., 
    Kenny, M., Key, R., Legler, D., Millard, R., Onken, R., Saunders, P., 
    Stalcup, M., contrib., Requirements for WOCE Hydrographic Programme Data 
    Reporting, WHPO Pub. 90-1 Rev. 2, 145pp., 1994. 

Key, R.M., WOCE Pacific Ocean radiocarbon program, Radiocarbon, 38(3), 415-423, 
    1996. 

Key, R.M., P.D. Quay, G.A. Jones, A.P. McNichol, K.F. Von Reden and R.J. 
    Schneider, WOCE AMS Radiocarbon I: Pacific Ocean results; P6, P16 & P17, 
    Radiocarbon, 38(3), 425-518, 1996. 

Key, R.M. and P. Schlosser, S4P: Final report for AMS 14C samples, Ocean Tracer 
    Lab Technical Report 99-1, January, 1999, 11pp. 

Leboucher, V., J. Orr, P. Jean-Babtiste, M. Arnold, P. Monfrey, N. Tisnerat-
    Laborde, A. Poisson and J.C. Duplessey, Oceanic radiocarbon between 
    Antarctica and South Africa along WOCE section I6 at 30°E, Radiocarbon, 41, 
    51-73, 1999. 

McNichol, A.P., G.A. Jones, D.L. Hutton, A.R. Gagnon, and R.M. Key, Rapid 
    analysis of seawater samples at the National Ocean Sciences Accelerator 
    Mass Spectrometry Facility, Woods Hole, MA, Radiocarbon, 36 (2):237-246, 
    1994. 

NOSAMS, National Ocean Sciences AMS Facility Data Report #99-043, Woods Hole 
    Oceanographic Institution, Woods Hole, MA, 02543, 2/16/1999. 

Osborne, E.A., A.P. McNichol, A.R. Gagnon, D.L. Hutton and G.A. Jones, Internal 
    and external checks in the NOSAMS sample preparation laboratory for target 
    quality and homogeneity, Nucl. Instr. and Methods in Phys. Res., B92, 158-
    161, 1994. 

Rubin, S. and R.M. Key, Separating natural and bomb-produced radiocarbon in the 
    ocean: The potential alkalinity method, Global Biogeochem. Cycles, in 
    press, 2002. 

Sabine, C.L. and R.M. Key, Surface Water and Atmospheric Underway Carbon Data 
    Obtained During the World Ocean Circulation Experiment Indian Ocean Survey 
    Cruises (R/V Knorr, December 1994-January 1996), ORNL/CDIAC-103, NDP-064, 
    Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, 
    Oak Ridge TN, 89 pp., 1997. 

Sabine, C.L., R. Wanninkhof, R.M. Key, C. Goyet, R. Millero, Seasonal CO2 
    fluxes in the tropical Indian Ocean, Mar. Chem., 72, 33-53, 2000. 

Schneider, R.J., A.P. McNichol, M.J. Nadeau and K.F. von Reden, Measurements of 
    the oxalic acid I/oxalic acid II ratio as a quility control parameter at 
    NOSAMS, In Proceedings of the 15th International 14C Conference, 
    Radiocarbon, 37(2), 693-696, 1995. 

Stuiver, M. and H.G. Ostlund, GEOSECS Indian Ocean and Mediterranean 
    radiocarbon, Radiocarbon, 25(1), 1-29, 1983. 





_________________________________________________________________________________________________________
_________________________________________________________________________________________________________





WHPO DATA PROCESSING NOTES I01E
            
            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
1998-02-04  Anderson      BTL/SUM                Fixed line & expocode #s, & sta. dates
            i01esu.txt 
            Changed first header from R/V KNORR, I1,KN145,  11  to 
              R/V KNORR CR. KN145, LEG 12  WHP-ID I01E
            Added time stamp
            changed EXPOCODE from 316N145/11b to 316N145_12
            changed WOCE SECT from I1 to I01E 
            latitude was not left justified, corrected this
            deleted last record in file, it only had   
            
            The following stations had the wrong date.  The cast started 
            before midnight and ended after midnight according to the time but 
            the date used was the same for the BE, BO, and EN event codes.

                          Sta. Event  Original  Changed to
                           #   Code   Date      Date
                         ----  -----  --------  ----------
                          966  EN     093095    100195
                          987  EN     100795    100895 
                          996  EN     100995    101095 
                         1002  EN     101095    101195 
            i1b.sea      
            Changed first header EXPOCODE and WHP-ID to conform with .sum 
            file.
              EXPOCODE 31ka45 to 316N145_12, and WHP-ID WOCE to I01E.
            Changed CRUISE DATES 082995-101695 to 093095-101695
            Added time stamp
            Deleted last record in file, in only had   
            CHANGED FILE NAME TO i01ehy.txt  
            
1999-08-02  Schwartz      CTD                    Submitted for DQE
            
1999-08-02  Schwartz      Cruise Report          Submitted  
            
2002-01-08  Mantyla       BTL DQE                Submitted  
            
2000-06-19  Kozyr         CO2                    Final Data Submitted
            I have put the final/public CO2-related data files for the 
            Indian Ocean WOCE Section I1W and I1E to the WHPO ftp INCOMING 
            area. There are two CO2 parameters in the files: Total CO2 and 
            Total Alkalinity with quality flags.
            
2000-08-03  Bartolacci    CTD                    ctd files for i01e and i01w split
            Since the splitting of I01 into east and west lines, the ctd 
            files for this cruise have remained as one zip file containing all 
            stations for both east and west lines.  As per Lynne Talley, I 
            have split the east stations from the total zip file (stations 
            962-1014 according to the sumfile) and rezipped them. They have 
            replaced the original file which was renamed to indicate it 
            contains all stations and moved to the original directory.
            
2000-09-14  Kappa        Cruise Report           cfc doc added to pdf file
            
2000-10-17  Jenkins      He/Tr                   Submitted  
            Reformatting needed
            
2000-11-15  Anderson      HELIUM/NEON            Converted to WOCE format
            I have put the Jenkins helium and neon in WOCE format. There 
            were no quality codes so I set the HELIUM, DELHE3, and NEON to 2.
            
2001-01-04  Anderson      CTDTMP/OXY/CTDOXY      Update Needed
            Working on an updated copy of i01ehy.txt (ANDY_ROSS.i01ehy.nut) 
            from Andy Ross at OSU.  This is the same data as was previously 
            on-line, but the nutrient data has been corrected for units 
            (previously uM/L, now uM/kg).
            
            Before putting this file back on-line, need to fix a few other 
            problems:
            a)  CTDTMP units are in ITS-68, should be ITS-90.  All data need 
                to be multiplied by 0.99976 to convert to ITS-90.
                Need to update header.
            b)  OXYGEN and CTDOXY are in wrong units.  Need to be converted 
                from ml/l to uM/kg.
                Need to update headers.
                THIS NEEDS TO BE DONE FIRST, before converting CTDTMP to ITS-90.
            c)  Formatting is incorrect for PO4, CFC11+12, OXYGEN and CTDOXY.
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2001-01-22  Anderson      TCARBN/ALKALI          Data reformatted
            Converted CTDTMP from -68 to -90, changed header.  Reformatted 
            data columns in hyd file to comply with WOCE specs.  Removed FCO2 
            column and associated Quality code (was '1').
            ALSO, changed the quality codes for previously merged ALKALI and 
            TCARBN data from '1' to '2' where data is present.
            Realized after making other conversions, also needed to convert 
            Theta from ITPS-68 to ITS-90.  Used most up-to-date hyd file to 
            make this conversion (multiplied all values by 0.99976).
            
2001-02-01  Anderson      HE, DELHE3, NEON       Data merged into BTL file
            Merged TRITUM, TRITIER, HELIUM, HELIER, DELHE3, DELHER, NEON, 
            NEONER from Sarilee's reformateed data files into hyd file.
            Data merged ok.
            NOTE: There were two values submitted for 979/1/25 (sta/cst/samp)
                  TRITUM and TRITIER.  Only merged first value into hyd file.
            
2001-02-01  Anderson      TRITUM/TRITIER         Data merged into BTL file
            Merged TRITUM, TRITIER, HELIUM, HELIER, DELHE3, DELHER, NEON, 
            NEONER from Sarilee's reformateed data files into hyd file.
            Data merged ok.
            NOTE: There were two values submitted for 979/1/25 (sta/cst/samp)
                  TRITUM and TRITIER.  Only merged first value into hyd file.
            
2001-06-21  Uribe         BTL                    Exchange file online
            Bottle exchange files was put online.
            
2001-06-27  Uribe         CTD                    Exchange file online
            CTD exchange files were put online.
            
2001-09-18  Wisegarver    CFCs                   Submitted, update needed
            This is information regarding line: I01E
            ExpoCode:      316N145_12
            Cruise Date:   1995/08/29 - 1995/09/28
            From:          WISEGARVER, DAVID
            Email address: wise@pmel.noaa.gov
            Institution:   NOAA
            Country:       USA
            The directory this information has been stored in is:
              20010918.165552_WISEGARVER_I01E
            The format type is:  ASCII   
            The data type is:    BottleFile 
            The Bottle File has the following parameters: 
              CFC-11,CFC-12
            The Bottle File contains:
              CastNumber StationNumber BottleNumber SampleNumber
            WISEGARVER, DAVID would like the data PUBLIC.
            And would like the following done to the data: merge final dqe cfc's
            Any additional notes are: 
            Submitted for D. Wyllie. CFC's on SIO98 Scale
            
2001-09-27  Mantyla       NUTs/S/O               DQE Report Submitted
            
2001-12-26  Uribe         CTD                    Exchange file online
            CTD has been converted to exchange using the new code and put online.
            
2002-01-08  Hajrasuliha   CTD                    Internal DQE completed
            created *check.txt file for the cruise created *.ps files for 
            this cruise.
            
2002-01-08  Anderson      BTL                    Exchange file online
            Made new exchange file and put online.
            
2002-01-08  Anderson      BTL/SUM                DQ report online, 
            The .sea file with the results of Arnold Mantyla's data quality 
            evaluation and QUALT2 flags has been put online.  Corrected a couple 
            of error in the .sum file and put new file online.  Jerry Kappa has 
            been sent the DQ report.
            
2002-02-28  Bartolacci    CFCs                   DQE'd data submitted
            I have placed the updated dqe'd CFC data sent by Wisegarver in 
            the following directory: .../onetime/indian/i01/i01e/original/ 
            2001.09.18_I01E_CFC_DQE_WISEGARVER included are data file and 
            submission form README file. Data are in need of merging at this 
            time.
            
            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2002-04-01  Anderson      DELC13                 Submitted
            Date: Mon, 1 Apr 2002 09:49:35 -0800 (PST)
            From: WHPO Website <http@odf.ucsd.edu>
            To:   dgerlach@whoi.edu, jrweir@whpo.ucsd.edu, whpo@ucsd.edu
            Subject:  WHPO DATA I01E: OTHER from GERLACH
            This is information regarding line: I01E
            ExpoCode: 
            Cruise Date:   1995/09/30 - 1995/10/16
            From:          GERLACH, DANA
            Email address: dgerlach@whoi.edu
            Institution:   WHOI
            Country:       USA
            The file:      C:\My Documents\C13-
              project\whpo_indian_march02\whpo_i01e.txt - 2667 bytes
            has been saved as:  20020401.094935_GERLACH_I01E_whpo_i01e.txt
            in the directory:   20020401.094935_GERLACH_I01E
            The data disposition is:
            • Public  
            The file format is:
            • Plain Text (ASCII) 
            The archive type is:
            • NONE - Individual File 
            The data type(s) is:
            • Other: flagged 13C data
            The file contains these water sample identifiers:
            • Cast Number (CASTNO)
            • Station Number (STATNO)
            • Bottle Number (BTLNBR)
            GERLACH, DANA would like the following action(s) taken on the 
            data:
            • Merge Data
            • Place Data Online
            Any additional notes are:
            • NOSAMS expocode affiliated with this line is:  316N145/11.   
            Any questions or concerns, please contact  
            • Dana Gerlach (dgerlach@whoi.edu) or
            • Ann McNichol  (amcnichol@whoi.edu).  
            
2002-04-12  Buck          C14                    Submitted
            Moved data from /usr/export/ftp-incoming to 
            i01/i01e/original/20020410_KEY_I1_C14. It is a CSV file and I 
            added the following heading to it:
            #I01E/W,316N145_11-12,Key 
            Data belongs to both I01E and I01W.
            
2002-08-13  Anderson       C13/C14/CO2/ALK/CFCs  Data Online
            Merged the DELC14 and C14ERR from Key, the DELC13 from Gerlach, 
            the TCARBN and ALKAL from Kozyr, and the CFCs from Wisegarver. 
            Made new exchange file.
            Merge notes for i01e:
            Merged the DELC14 and C14ERR from file I1.C14 found in 
              /usr/export/ html-
              public/data/onetime/indian/i01/i01e/original/20020410_KEY_I1_C14 
            into the online file 20010927WHPOSIOSA.
            Merged the DELC13 from file 
              20020401.094935_GERLACH_I01E_whpo_i01e.txt 
            found in /usr/export/html-public/data/onetime/indian/i01/ 
              i01e/original/20020401.094935_GERLACH_I01E into the online file.
            Merged the new TCARBN and ALKAKI from file i1ecarb.dat found in 
            /usr/export/ html-public/data/onetime/indian/i01/ 
              i01e/original/2000.06.19_I1_CARB_KOZYR into online file.
            Merged the new CFC's from file:
            20010918.165552_WISEGARVER_I01E_i01e_CFC_DQE.dat
            found in /usr/export/html-public/data/onetime/indian/i01/  
              i01e/original/2001.09.18_
            I01E_CFC_DQE_WISEGARVER into the online file.
            
2002-08-15  Anderson      He/Tr/Helium/Neon      Data Online  
            Merged the DELHE3, DELHER, HELIUM, HELIER, NEON, NEONER, 
            TRITIUM, and TRITER from Jenkins. Made new exchange file. 
            Merge notes for i01e:
            HE3, DELHER, HELIUM, HELIER, NEON, NEONER from file wihe.dat 
            found in 
            /usr/export/html-public/data/onetime/indian/i01/ 
              i01e/original/2000.10.17_I01E_TRITIUM_HELIUM_JENKINS 
            into online file 20020813WHOPSIOSA.
            Merged the TRITIUM and TRITER from file witrit.dat found in above 
            directory into online file.
            
            This merging had been done earlier by Stacey Anfuso but there is 
            no rcs (at least I can't find it) and the file she merged appears 
            not to have been put online or somehow was replaced with a file 
            that did not have these parameters.
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2002-10-05  Diggs         BTL                    Units corrected
            Fixed original WOCE formatted bottle file per Tim Boyer's 
            (NODC/OCL) suggestions to me.
            Units line: 
              This is the units line from i01e_hy1.csv:
            DBAR,ITS-90,PSS-78,,PSS-78,,UMOL/KG,,UMOL/KG,,UMOL/KG,,UMOL/KG,, 
              UMOL/KG,,UMOL/KG,,PM/K,,GPM/K,,G T,,U UMOL/K,,PERCNT,,G /MILL,,  
              /MILLE,,NMOL/KG,,E UMOL/K,,GUMOL/K,,,/MILLE,NMOL/KG, 
              PERCNT,NMOL/KG,ITS-90,TU&#034;
            Fixed units line, re-made HYD Exchange, NetCDF and inventories. 
            Re-zipped all relevant files, checked in JOA3.1 (OSX), copied 
            files to DVD 3.0 online site as well. Tarballed inventory, 
            exchange, and NetCDF and sent to Shannon Niou of NODC for 
            inclusion on the WOCE Version 3 DVD.
            
2003-04-16  Muus          CTDs/OXY/DELC13        Data Online
            Merged DELC13 decimal-2-data into bottle file. Merged new 
            CTDPRS, CTDTMP, CTDSAL, CTDOXY, THETA, SALNTY & OXYGEN from WHOI 
            into bottle file.
            Notes on I01E merging   Apr 16, 2003    D. Muus
            1. Changed all Helium and Tritium quality flag 1s associated with 
               missing data to 9s.
            2. Merged DELC13 from:
               /usr/export/html-public/data/onetime/indian/i01/i01e/original/
               20020401.094935_GERLACH_I01E/20020401.094935_GERLACH_I01E_whpo_ 
               i01e.txt
               into current web bottle file (20021005WHPOSIOSCD) to replace 1 
               decimal place data with 2 decimal place DELC13 data.
            3. Merged CTDPRS, CTDTMP, CTDSAL, CTDOXY, THETA, SALNTY, & OXYGEN 
               from:
               Jane Dunworth, WHOI, email of March 24, 2004.
               email data can be found in:
               /usr/export/html-public/data/onetime/indian/i01/i01e/original/
               2003.04.16.I01E_C13_CTDPTSO_SAL_OXY_MERGE_MUUS/
               dunworth.email030324.i01e.btldata

            Prior to merging, ITS-68 CTDTMP and THETA were changed to ITS-90 
            using ITS-90 = 0.99976(ITS-68) and CTDOXY and OXYGEN changed from 
            ml/l to UMOL/KG using cvuwoce on minerva.ucsd.edu.
            
            4. 2001/01/23 ANFUSO, S.   note in Data History. NUTRIENTS: Data 
               was originally submitted in uM/L units, PI recalculated and 
               resubmitted in uM/kg units. Also, original submission of nitrate 
               data was actually nitrate nitrite. This error has been corrected 
               in current data submission.
            
            Nutrients unchanged this version since only small changes in CTD 
            pressure, salinity and temperature for samples with nutrient 
            values.
            
            5. Made new exchange file for Bottle data.
            6. Checked new bottle file with Java Ocean Atlas.
            
2005-02-28  Anderson      HELIUM/NEON            Data Online
            i01e and i01w   
              Found file i1he.txt in 
              .../indian/i01/i01/original/2000.10.04_I1_BOTTLE. This file 
              contains the deep DELHE3, HELIUM, NEON, DELHER, HELIER, and 
              NEONER for i01e and i01w.
            I merged these parameters into the online files, and made new 
              exchangeand netcdf files.  There were no Q1 or Q2 flags so I set 
              them to 2.  
            
2008-06-17  Kappa         Cruise Report          Added C14 & CO2 reports & Data Processing Notes
            Added these WOCE/CCHDO Data Processing Notes
            Added 4 reports to pdf and text versions of cruise report:
            1) Carbon Dioxide, Hydrographic and Chemical Data 
            2) Coulometric Total Carbon Dioxide Analysis
            3) Assessment of the Quality of the Shipboard Measurements of 
               Total Alkalinity
            4) Anthropogenic CO2 Inventory
            5) U.S. Woce Indian Ocean Survey: Final Report for Radiocarbon
            




WHPO DATA PROCESSING NOTES I01W

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
1998-02-04  Anderson      BTL/SUM                Fixed line & expocode #s, & 
            sta.dates
              i01wsu.txt - 
            Changed first header from R/V KNORR, I1,KN145,  11  to:
              R/V KNORR CR. KN145, LEG 11  WHP-ID I01W  
            Added time stamp
            changed EXPOCODE from 316N145/11a to 316N145_11
            changed WOCE SECT from I1 to I01W
            latitude was not left justified, corrected this  
            
            The following records had the wrong date.  The cast started before 
            midnight and ended after midnight according to the time but the 
            date used was the same for the BE, BO, and EN event codes.

                         Sta.  Event  Original  Changed to 
                               Code   Date      Date  
                         ---   -----  --------  ----------
                         857   BO     082995    083095  
                         862   EN     083195    090195 
                         880   EN     090695    090795 
                         885   BO     090795    090895
                         885   EN     090795    090895 
                         891   EN     090895    090995 
                         897   EN     091095    091195
                         904   EN     091295    091395
                         911   BO     091495    091595 
                         911   EN     091495    091595 
                         915   BO     091595    091695 
                         915   EN     091595    091695 
                         927   EN     091895    091995 
                         934   BO     092095    092195 
                         934   EN     092095    092195 
                         937   EN     092195    092295 
                         944   EN     092395    092495 
                         954   BO     092595    092695 
                         954   EN     092595    902695 
            i1a.sea 
            Changed first header EXPOCODE and WHP-ID to conform with .sum file.
              EXPOCODE 31ka45 to 316N145_11, and WHP-ID WOCE to I01W.
            Changed CRUISE DATES 082995-101695 to 082995-092895
            Added time stamp
            Deleted last record in file, it only had   
            CHANGED FILE NAME TO i01why.txt  
            
1998-09-16  Morrison      CTD                    Submitted  
            Plots, unencrypt data for workshop, NO public distrib after workshop
            
1998-09-29  Morrison      CTDOXY                 not yet submitted,   
            50 stas have bad ctd 02.  Bob Millard will take another look at them
            
1998-09-29  Talley        BTL                    Data Update:   
            Following changes ftp'd to WHPO.  Replace older HYD file with 
            this one (OK'd by PI):
            1. Combine i01e and i01w into one line: i01
            2. Change expocode from 31ka45 to 316N145
            3. Bottle flag for station 1005, 1, 23 at 349.7 dbar is 3 and 
               salinity is 4.
            It looks like all nutrients are bad here as well.  I suggest that 
            they all be flagged 4.  Oxygen doesn't look out of place, but 
            maybe for consistency, it should be flagged 3.
            
1998-12-22  Srinivasan    He/Tr Deep             Submitted  Preliminary, not for DQE
            This is Ashwanth Srinivasan from Noble Gas Isotope Lab , RSMAS, 
            Univ of Miami. We have submitted four files, i7he.txt, i9he.txt 
            and i1he.txt and readme.he to the incoming directory at your ftp 
            site. These files contain tritium, helium and neon data from WOCE 
            I7N, I9N and I1 cruises. These data are preliminary and 
            proprietary and the format is explained in the readme.he file.  In 
            case of problems or questions please email to one of the following 
            addresses:
            Zafer Top:            ztop@rsmas.miami.edu
            Ashwanth Srinivasan:  asrinivasan@rsmas.miami.edu
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
1999-04-06  Bartolacci    SUM                    Website Updated
            S.Anderson's (1998-02-04) updated files online
            
1999-05-25  Top           He/Tr Deep             Data are Public  
            My helium-tritium data from IO legs I1-I7N and I9N may now be 
            made public. It should be kept in mind though that we are working 
            on the synthesis ; some modifications may occur. Also there are 
            some papers are in progress; interested parties should check with 
            the tracer group (Schlosser, Jenkins, Lupton, Top)
            
1999-06-30  Morrison      CTD/BTL/SUM            Submitted  
            6/27/99
            The WHOI processing programs could not handle 4 digit station 
            numbers, therefore the processed data as passed to me for final 
            approval had files with station numbers 857 - 999 and 00 - 14.  I 
            changed the names of the CTD files and the stations numbers in the 
            CTD, SEA and SUM files to reflect the actual WOCE stations 
            numbers:  857 - 1014.
             
            John M. Morrison, Chief Scientist, WOCE I1
            
            6/29/99
            I have just placed the final, corrected data for WOCE Indian Ocean 
            Leg I1 on your server.  All of the calibration documention is in 
            the directory DOC.  Sorry that this was not submitted sooner, but 
            I did not receive the data until last fall and was busy cleaning 
            up JGOFS Indian Ocean and Southern Ocean data for submission to 
            the JGOFS database. As you can see, the WOCE I1 dataset has some 
            problems with the CTD data in that it was necessary to use 
            Falmouth Scientific CTD's for the cruise (all of the WOCE Neil 
            Brown WHOI CTD's were not working when the ship left of the WOCE 
            Neil Brown WHOI CTD's were not working when the ship left Muscat, 
            Oman.
            
            Let me know if you have received this dataset. 
            
1999-06-30  Morrison      CTD                    Data are Final  
            I have just placed the final, corrected data for WOCE Indian 
            Ocean Leg I1 on your server.  All of the calibration documention 
            is in the directory DOC.
            
            As you can see, the WOCE I1 dataset has some problems with the CTD 
            data in that it was necessary to use Falmouth Scientific CTD's for 
            the cruise (all of the WOCE Neil Brown WHOI CTD's were not working 
            when the ship left Muscat, Oman.
            
1999-07-26  Swartz        CTD/DOC                Data Update:   
            
1999-09-29  Falkner       BA                     Data Update:   
            The quality of the Ba data from most WOCE legs in the Indian 
            Ocean turned out to be quite poor; far worse than attainable 
            analytical precision (+/-20% as opposed to 2%). We recorded many 
            vials which came back with loose caps and evaporation associated 
            with that seems to be the primary problem.  The only hope I have 
            of producing a decent data set is to run both Ba and a 
            conservative element simultaneously and then relating that to the 
            original salinity of the sample.  We will be taking delivery on a 
            high resolution ICPMS here at OSU sometime this winter which would 
            make the project analytically feasible and economical.  I do not 
            presently have the funds in hand to do this and so have archived 
            the samples for the time being. I don't think the WHPO would 
            derive any benefit from the present data set.
            KKF
            
1999-12-22  Elder         Cruise Report          Radiocarbon Data Report Submitted
            
2002-01-08  Mantyla       BTL DQE                Submitted  
            emailed by S. Anderson
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2000-03-27  Morrison      CTD/BTL                Website Updated:  Data are Public
            not hearing any decenting comments from my fellow PI's, I 
            release the WOCE I1 data set to the general public.
            
2000-05-01  Warner        CFCs                   Data ata are public
            I just uploaded the revised CFC data for WOCE I1.  It should be 
            made public once it is merged.  I have also included a report to 
            be merged (eventually) into the metadata files.
            
2000-06-19  Diggs         ALKALI/TCARBN          Submitted  
            Bottle: (tcarbn, alkali) data file received in INCOMING. In perfect 
            WHP format. Will be merged asap.
            
            From Alex Kozyr
            I have put the final/public CO2-related data files for the Indian 
            Ocean WOCE Section I1W and I1E to the WHPO ftp INCOMING area. 
            There are two CO2 parameters in the files: Total CO2 and Total 
            Alkalinity with quality flags. Please confirm the data submission.
            
2000-08-02  Kappa         Cruise Report          pdf, txt docs online; need cfc report
            
2000-08-03  Bartolacci    CTD                    ctd files for i01e and i01w split
            Since the splitting of I01 into east and west lines, the ctd 
            files for this cruise have remained as one zip file containing all 
            stations for both east and west lines.  As per Lynne Talley, I 
            have split the east stations from the total zip file (stations 
            962-1014 according to the sumfile) and rezipped them. They have 
            replaced the original file which was renamed to indicate it 
            contains all stations and moved to the original directory.
            
2000-08-12  Ross          SAL/NUTs/NITRAT        Data Update:   
            Per your request - I've attached i0why.nut and i01ehy.nut files 
            containing nutrient data in the units of umol/kg.  The original 
            I01WHY.txt and I01EHY.txt files that contained nutrient data in 
            umol/liter units were downloaded from the WOCE program office 
            sites:
              http://whpo.ucsd.edu/data/onetime/indian/i01/i01e/index.htm and
              http://whpo.ucsd.edu/data/onetime/indian/i01/i01w/index.htm and 
            were used as the data sources.  The attached files are in text 
            format.
            
            For your records, in the conversion process the bottle salinity 
            values were used to determine sample density along with the mean 
            laboratory temperature for each leg as determined from our 
            nutrient analysis notes.  When a bottle salinity value was 
            unavailable, the corresponding CTD salinity value was used.  The 
            mean lab temperature for I01W was 25∞C and 26∞C for I01E.
            
            An important note:
            We also realized that the nitrate in the original files was in 
            fact nitrate+nitrite. This has also been corrected in the new file 
            versions that are attached.
            
2000-09-07  Huynh         Cruise Report          Website Update
            cfc report added to txt version; pdf pending
            
2000-09-14  Kappa         Cruise Report          cfc doc added to pdf file
            
2000-10-04  Uribe         BTL                    Found data newer than file online
            Moved file i01hy.txt from incoming file in /usr/export/. Website 
            indicated i01e was equivalent to i01w.  File stamp is 
            WHPOSIO19980928LDT. Online stamp is WHPOSI019980204SA. This 
            indicates file data to be more recent than online version.  Path 
            is i01/i01e/original/1998.09.28_HY_LDT.
            
2000-10-17  Jenkins       TRITUM                 Preliminary Data Submitted
            * Files for Tritium Data: 
                    WOCE Indian Ocean = WITrit.dat   Contains all legs
                    WOCE Pacific P10  = WP10Trit.dat
                    WOCE Pacific P13  = WP13Trit.dat
                    WOCE Pacific P14c = WP14cTrit.dat
                    WOCE Pacific P18  = WP18Trit.dat
                    WOCE Pacific P19  = WP19Trit.dat
                    WOCE Pacific P21  = WP21Trit.dat
                    SAVE South Atlnt  = SAVETrit.dat
            * Column Layout as follows:  Station, Cast, Bottle, Pressure, 
              Tritium, ErrTritium
            * Units as follows:  Tritium and ErrTritium in T.U.
            * All data are unfortunately still preliminary until we have 
              completed the laboratory intercomparision and intercalibration 
              that is still underway.
            
            

DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2000-10-17  Jenkins       HELIUM/DELHE3          Preliminary He, DelHe3, Neon Submitted
            *Files for Helium and Neon Data: 
                    WOCE Indian Ocean = WIHe.dat   Contains all legs
                    WOCE Pacific P10 = WP10He.dat
                    WOCE Pacific P18 = WP18He.dat
                    WOCE Pacific P19 = WP19He.dat
                    WOCE Pacific P21 = WP21He.dat
            * Column Layout as follows:
              Station, Cast, Bottle, Pressure, Delta3He, ErrDelta3He, 
              ConcHelium, ErrConcHelium, ConcNeon, ErrConcNeon
            * Units as follows:
              Delta3He and ErrDelta3He in %
              ConcHelium, ErrConcHelium, ConcNeon, and ErrConcNeon in nmol/kg
            * Null values (for ConcNeon and ErrConcNeon only ) = -9.000
            * All data are unfortunately still preliminary until we have 
              completed the laboratory intercomparision and intercalibration 
              that is still underway.
            * Files for Helium and Neon Data: 
                    WOCE Indian Ocean = WIHe.dat   Contains all legs
                    WOCE Pacific P10 = WP10He.dat
                    WOCE Pacific P18 = WP18He.dat
                    WOCE Pacific P19 = WP19He.dat
                    WOCE Pacific P21 = WP21He.dat
            * Column Layout as follows:
              Station, Cast, Bottle, Pressure, Delta3He, ErrDelta3He, 
              ConcHelium, ErrConcHelium, ConcNeon, ErrConcNeon
            * Units as follows:
              Delta3He and ErrDelta3He in %
              ConcHelium, ErrConcHelium, ConcNeon, and ErrConcNeon in nmol/kg
            * Null values (for ConcNeon and ErrConcNeon only ) = -9.000
            * All data are unfortunately still preliminary until we have 
              completed the laboratory intercomparision and intercalibration 
              that is still underway.
            
2000-11-08  Anderson      HELIUM/NEON            Reformatted by WHPO
            I have put the Jenkins helium and neon in WOCE format. There 
            were no quality codes so I set the HELIUM, DELHE3, and NEON to 2.
            
2000-11-13  Anderson      TRITUM                 Reformatted by WHPO
            I have put the Jenkins tritium data into WOCE format.  There 
            were no quality codes so I set the TRITUM to 2. 
            
2000-11-21  Anfuso        NUTs                   Update Requested  
            Dear Dr. Gordon,
            We are reviewing all data submitted to WHPO for the Indian Ocean 
            WOCE cruise lines and would like to request that you resubmit the 
            nutrient data for I01E/I01W in uM/Kg units.  The current data 
            submission indicates the nutrient values are in uM/L units.  
            
            All other nutrient data submissions from you research group for 
            the Indian Ocean WOCE lines indicate the data have been submitted 
            in uM/Kg units.
            
2000-11-27  Uribe         He/Tr Shallow          Data Update:   
            Files tritfrmt.txt, savetrit.dat,  witrit.dat, heformat.txt and 
            wihe.dat were moved from Jenkins' original data directory.  
            witrit.dat contians tritium data for the indian cruises.  wihe.dat 
            contains helium data for indian cruises.  These files contain 
            original data that was later re-formatted by S. Anderson.  Files 
            received by Jenkins on October 17th, 2000.
            
2001-01-23  Anfuso        BTL                    BTL file reformatted
            Bottle: (ctdtmp, ctdoxy, theta, oxygen, silcat, nitrat, nitrit, 
            phspht, tcarbn, alkali)
            
            NUTRIENTS: Data was originally submitted in uM/L units, PI 
              recalculated and resubmitted in uM/kg units. Also, original 
              submission of nitrate data was actually nitrate nitrite. This 
              error has been corrected in current data submission.
              CTDOXY & OXYGEN: Data was originally in ml/l, Sarilee converted to 
              uM/kg.
            FCO2: Removed this data column and associated quality flag. All 
              data values were -9.0.
            CTDTMP & Theta: Converted data from ITPS-68 to ITS-90.
            TCARBN & ALKALI: Changed quality flag from 1 to 2 where data 
              exists.
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2001-02-01  Anfuso        He/Tr/Shallow           Website Updated:  Data Online
            Bottle: (tritum, helium, delhe3, neon, triter, helier, delher, 
              neoner)
            Merged TRITUM, TRITER, HELIUM, HELIER, DELHE3, DELHER, NEON, 
              NEONER data into hyd file. Updated hyd file is on-line.
            NOTE:  The following NEON data (sta/cst/samp) had a -9.000 data 
              value, with a -0.045NMOL/KG NEONER value.  This doesn't make 
              sense.  Assumed samples were never drawn, NEONER value changed to 
              -9.000.
            866/1/28, 26, 24, 22, 21; 873/1/9; 874/1/2
            Also, the following TRITUM and TRITIER had duplicate data values 
              submitted, only merged first value into hyd file:  
              880/1/9;885/1/1;945/1/1;951/1/21
            
2001-02-05  Anfuso        HE/TR/NEON             Data merged into BTL file
            Merged TRITUM, TRITIER, HELIUM, HELIER, DELHE3, DELHER, NEON, 
              NEONER from Sarilee's reformateed data files into hyd file.
            Data merged ok.
            NOTE:  The following NEON data (sta/cst/samp) had a -9.000 data 
              value, with a -0.045NMOL/KG NEONER value.  This doesn't make 
              sense.  
            Assumed samples were never drawn, NEONER value changed to -9.000.
                    866/1/28, 26, 24, 22, 21; 873/1/9; 874/1/2
            Also, the following TRITUM and TRITIER had duplicate data 
            values submitted,
              only merged first value into hyd file:
              880/1/9;885/1/1;945/1/1;951/1/21
            
2001-02-06  Anfuso        ALKALI/TCARBN          Website Updated:  Data Online
            Merged updated TCARBN and ALKALI data and quality codes into hyd 
            file. Merged over preliminary version of data. Updated hyd file is 
            on-line. Merging notes are in original subdir 
            2000.06.19_I01W_CARB_KOZYR/00_Readme.
            
2001-02-07  Mantyla       NUTs/S/O               DQE Begun  
            Sure, I would be glad to look over the Indian Ocean data for 
            you. Sarilee has started plotting up I01 for me to start on. 
            
2001-06-21  Uribe         BTL                    Exchange file online
            Bottle exchange file was put online.
            
2001-06-22  Muus          He/Tr Deep             Submitted/not on web  
            I01E,I01W   Z. Top deep helium/tritium received May 25, 1999 not 
            on web.
            
2001-08-23  Mantyla       OXYGEN                 Decimal correction needed
            I took another look at the exchange format for I 01E. The 
              nutrient conversion back to UM/L appear to be OK, I had misread 
              one station. However, the O2 data, listed as ML/L, should carry 
              two more decimal places. The conversion is going from a 4 
              significant firure to only 2.
            What is supposed to be listed under the depth column? Since it 
              appears with each sample and is next to the CTD pressure, I would 
              assume that the sample depth would be listed there. However, what 
              is showing up is the bottom sounding for every sample.
            At 08:55 AM 8/23/01 -0700, James H. Swift wrote: WHPO - Would 
              someone kindly create a new bottle exchange file for I01E 
              (316N145_12). There is a clear problem with the oxygens and 
              nutrients in the present exchange file on line for this cruise 
              (i01e_hy1.csv) and I want to see if it goes away when we create a 
              new file.
            
2001-08-29  Top           NEON                   Status Changed to Public
            Zafer - Is it safe to assume that all WOCE One-Time Survey neon 
            data from you are now public?  Jim
                Yes they are. - Zafer
            
2001-11-01  Mantyla       NUTs/S/O               DQE Report Submitted
            
2001-12-17  Hajrasuliha   CTD/BTL                Internal DQE completed
            The following are results from the examminer.pl and plotter.pl 
            code that were run on this cruise. Not all of the errors are 
            reported but rather a summery of what was found. For more 
            information you can go to the cruise directory, and look at the 
            NEW file called CruiseLine_check.txt. Two plot files are also 
            present. _oxy.ps and _sal.ps
                     _oxy.ps and _sal.ps files created.
            Exchange CTD file not created for this cruise.
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2001-12-26  Uribe         CTD                    Exchange file online
            CTD has been converted to exchange using the new code and put 
            online.
            
2002-01-08  Anderson      BTL                    Exchange file online
            Made new exchange file and put online.
            
2002-01-08  Anderson      BTL/SUM                DQ report online, 
            The .sea file with the results of Arnold Mantyla's data quality 
              evaluation and QUALT2 flags has been put online. 
            Corrected a couple of error in the .sum file and put new file 
              online.
            Jerry Kappa has been sent the DQ report.
            
2002-02-28  Bartolacci    CFC's                  DQE'd data submitted, ready to be merged
            I have placed the updated dqed CFC data sent by Wisegarver in 
            the following directory
            .../onetime/indian/i01/i01w/original/ 
            2001.09.18_I01W_CFC_DQE_WISEGARVER
            included are data file and submission form README file. Data are 
            in need of merging at this time.
            
2002-04-01  Gerlach       DELC13                 Submitted  
            Date:  Mon, 1 Apr 2002 09:51:17 -0800 (PST)
            From:  WHPO Website <http@odf.ucsd.edu>
            To:    dgerlach@whoi.edu, jrweir@whpo.ucsd.edu, whpo@ucsd.edu
            Subject:       WHPO DATA I01W: OTHER from GERLACH
            This is information regarding line: I01W
            ExpoCode:      316N145/11
            Cruise Date:   1995/08/29 - 1995/10/16
            From:          GERLACH, DANA
            Email address: dgerlach@whoi.edu
            Institution:   WHOI
            Country:       USA
            
            The file:  C:\My Documents\C13-
            project\whpo_indian_march02\whpo_i01w.txt - 8503 bytes
            has been saved as:  20020401.095117_GERLACH_I01W_whpo_i01w.txt
            in the directory:  20020401.095117_GERLACH_I01W
            The data disposition is: Public  
            The file format is:      Plain Text (ASCII) 
            The archive type is:     NONE - Individual File 
            The data type(s) is:     Other: flagged 13C data
            The file contains these water sample identifiers:
                      Cast Number (CASTNO)
                      Station Number (STATNO)
                      Bottle Number (BTLNBR)
            GERLACH, DANA would like the following action(s) taken on the 
            data:
                      Merge Data
                      Place Data Online
            Any additional notes are:
                      Questions or concerns, please contact:
                        Dana Gerlach (dgerlach@whoi.edu) or
                        Ann McNichol (amcnichol@whoi.edu)
            Date:     Mon, 1 Apr 2002 10:36:36 -0800 (PST)
            From:     WHPO Website <http@odf.ucsd.edu>
            To:       dgerlach@whoi.edu, jrweir@whpo.ucsd.edu, whpo@ucsd.edu
            Subject:  WHPO DATA I01W: DOC/OTHER from GERLACH
            This is information regarding line:  I01W
            ExpoCode:      316N145/11
            Cruise Date:   1995/08/29 - 1995/10/16
            From:          GERLACH, DANA
            Email address: dgerlach@whoi.edu
            Institution:   WHOI
            Country:       USA
            The file:  C:\My Documents\C13-
            project\whpo_indian_march02\i01w_desc.txt - 259 bytes
            has been saved as: 20020401.103636_GERLACH_I01W_i01w_desc.txt
            in the directory:  20020401.103636_GERLACH_I01W
            The data disposition is: Public  
            The file format is:      Plain Text (ASCII) 
            The archive type is:     NONE - Individual File 
            The data type(s) is:     Documentation\n          Other: flagged 
            13C replicate data
            The file contains these water sample identifiers:
                      Cast Number (CASTNO)
                      Station Number (STATNO)
                      Bottle Number (BTLNBR)
            GERLACH, DANA would like the following action(s) taken on the 
            data:
                      Other: use as reference
            Any additional notes are:
                      This description file lists the individual flags for the 
            replicate values.  \n          It is a detailed listing of those 
            stations which have c13f = 6. 
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2002-04-10  Key           C14                    Submitted  
            The file:  I1.C14 - 87908 bytes has been saved as:   
            20020410.072032_KEY_ALL&#x2020;INDIAN&#x2020;OCEAN_I1.C14 
            in the directory:  
            20020410.072032_KEY_ALL&#x2020;INDIAN&#x2020;OCEAN
            
            The data disposition is: Public
            The bottle file has the following parameters: STATION, CAST, 
            BOTTLE, DELC14, C14ERR, C14F
            The file format is: Plain Text (ASCII)
            The archive type is: NONE - Individual File
            The data type(s) is: Bottle Data (hyd)
            The file contains these water sample identifiers: Cast Number 
            (CASTNO), Station Number (STATNO), Bottle Number (BTLNBR)
            
            KEY, ROBERT would like the following action(s) taken on the data: 
            Merge Data, Place Data Online, Update Parameters
            
            Any additional notes are: I've included the C14 from the French 
            occupation of I6S.  All files are same format.  Tool does not 
            accept mput syntax
            
2002-08-14  Anderson      BTL                    C13/C14/Data Online  
            Merged DELC14 and C14ERR from Key, DELC13 from Gerlach, TCARBN 
              adn ALKALI from Kozyr, and CFCs from Wisegarver. Made new exchange 
              file. 
            Merge notes for i01w:
            Merged the DELC14 and C14ERR from file I1.C14 found in 
              /usr/export/ html-
              public/data/onetime/indian/i01/i01w/original/20020410_KEY_I1_C14 
              into the online file 20011026WHPOSIOSA.
            Merged the DELC13 from file 
            20020401.095117_GERLACH_I01W_whpo_i01w.txt found in 
            /usr/export/html-
            public/data/onetime/indian/i01/i01w/original/20020401.095117_ 
            GERLACH_I01W into the online file.
            
            Merged the new TCARBN and ALKAKI from file i1wcarb.dat found in 
            /usr/export/
            html-
            public/data/onetime/indian/i01/i01w/original/2000.06.19_I01W_CARB_
            KOZYR into online file.
            
            Merged the new CFC's from file 
            20010918.165933_WISEGARVER_I01W_i01w_CFC_DQE.dat
            found in /usr/export/html-
            public/data/onetime/indian/i01/i01w/original/2001.09.18_
            I01W_CFC_DQE_WISEGARVER into the online file.
            
2002-08-15  Anderson      He/Tr/Neon             Website Updated:  Data Online
            Merged the DELHE3, DELHER, HELIUM, HELIER, NEON, NEONER, 
              TRITIUM, and TRITER from Jenkins. Made new exchange file. 
            Merge notes for i01w:
              Merged the DELHE3, DELHER, HELIUM, HELIER, NEON, NEONER from file 
              wihe.dat found in 
              /usr/export/html-
              public/data/onetime/indian/i01/i01w/original/2000.10.17_I01w_TRITI
              UM_HELIUM_ JENKINS into online file 20020814WHOPSIOSA.
            Merged the TRITIUM and TRITER from file witrit.dat found in above 
              directory into online file.
            This merging had been done earlier by Stacey Anfuso (2001/02/01) 
              according to the rcs, but the file she merged appears not to have 
              been put online or somehow was replaced with a file that did not 
              have these parameters.

            
            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2003-04-11  Muus          CTD/C13                Data merged into BTL file
            Merged DELC13 decimal-2-data into bottle file. Merged new 
            CTDPRS, CTDTMP, CTDSAL, CTDOXY, THETA, SALNTY & OXYGEN from WHOI 
            into bottle file. Changed some quality flags per WHOI notes and 
            results of Java Ocean Atlas check. Notes file sent to Jerry with 
            details. 
            Notes on I01W merging     Apr 11, 2003      D. Muus
            1. Merged DELC13 from:
               /usr/export/html-public/data/onetime/indian/i01/i01w/original/
               20020401.095117_GERLACH_I01W/20020401.095117_GERLACH_I01W_ 
               whpo_i01w.txt
               into current web bottle file (20020815WHPOSIOSA)
               to replace 1 decimal place data with 2 decimal place DELC13 data.
            2. Changed all Helium and Tritium quality flag 1s associated with 
               missing data to 1s.
            3. Replaced all BTNNBR, CTDSAL & CTDOXY quality flags with new 
               flags received March 24, 2003, from Jane Dunworth, WHOI
            4. Changed flag 1s for Station 863 to 4s per WHOI message:
               From jdunworth@whoi.edu Tue Mar 25 06:21:13 2003 found this is 
               in the cruise summary info. it seems like this cruise had serious 
               problems with calibration and instrumentation issues. you might 
               want to change the ctdsal & ctdoxy flags to 3 (questionable) or 4 
               (bad) for sta 863.
               STATION 863  Made the internally recording (IR) backup CTD, CTD 
                1338, the primary data for the station instead of CTD 9. CTD9's 
                oxygen and salinity in the down profile were bad due to noisy 
                pressure requiring heavy interpolation.  ICTD 1338 data was used 
                to make the down 2-db file.  CTD 9's info was left with the bottle  
                file. There were problems makeing the bottle file from the IR CTD.   
                Note, there are different up and down cals!, one for CTD1338, the 
                other for CTD9.
               Following note also found in Documentation: Station 863: CTD9 with 
                ICTD1338 in Memory mode. After Test station for CTD9, CTD 9 opened  
               and found dessicant packs to be caught btw boards, causing 
               components on board to short out. Thought was fixed, but 
               everything dropped out twice during this station. -USE ICTD1338 
               DATA FOR THIS STATION
            5. Merged CTDPRS, CTDTMP, CTDSAL, CTDOXY, THETA, SALNTY, & OXYGEN 
               from: Jane Dunworth, WHOI, email of March 24, 2004.
               email data can be found in:
                 /usr/export/html-
               public/data/onetime/indian/i01/i01w/original/
                 2003.04.08.I01W_C13_CTDPTS_SAL_OXY_MERGE_MUUS/
                 dunworth.email030324.i01w.btldata
               Prior to merging, ITS-68 CTDTMP and THETA were changed to ITS-90 
               using ITS-90 = 0.99976(ITS-68) and CTDOXY and OXYGEN changed from 
               ml/l to UMOL/KG using cvuwoce on minerva.ucsd.edu.
            6. Station 863 Sample 36 was deleted because CTDTMP & CTDSAL = 0 
               at 16 N Latitude surface.
                STNNBR    863  CTDPRS   2.4     SALNTY  35.6305  NITRIT  0.63
                Remaining parameters -9
                  CASTNO   1  CTDTMP   0.0029  OXYGEN 201.3     PHSPHT  1.24
                  SAMPNO  36  CTDSAL   0.0000  SILCAT   7.81    CFC-11  1.864
                  BTLNBR SIH024  CTDOXY 358.4  NITRAT  14.10    CFC-12  1.055
            7. 2001/01/23 ANFUSO, S.   note in Data History.
               NUTRIENTS: Data was originally submitted in uM/L units, PI 
               recalculated and resubmitted in uM/kg units. Also, original 
               submission of nitrate data was actually nitrate nitrite. This 
               error has been corrected in current data submission.  Nutrients 
               unchanged this version since only small changes in CTD pressure, 
               salinity and temperature for samples with nutrient values.
            8. Following CTDSAL and CTDOXY values differ from bottle values. 
               QUALT1 was 2.
                  Sta/Ca/Smp  CTDPRS    Bottle -  CTD           Changed QUALT2 to:
                                        Salt      Oxygen
                  890/1/1    2195.7db   No Btl S, No Btl o2          CTDOXY 4
                       /2    2195.2     No CTD S, No CTD o2
                          Smp1 - Smp2   ok        51.8 UMOL/KG
                  900/1/10    298.9     2.93 PSU  ok                 CTDSAL 4
                       /11    273.4     0.36      ok                 CTDSAL 4
                       /12    248.6     0.24      ok                 CTDSAL 4
                       /13    224.1     0.24      ok                 CTDSAL 4
                  901/1/6    1002.3     1.02      ok                 CTDSAL 4
                       /7     903.2     0.26      ok                 CTDSAL 4
                       /8     808.0     1.08      ok                 CTDSAL 4
                       /11    498.1     1.04      ok                 CTDSAL 4
                       /12    403.9     1.02      ok                 CTDSAL 4
                       /14    253.4     1.48      ok                 CTDSAL 4
                  902/1/4    1799.4     1.25      ok                 CTDSAL 4
               No changes were made to quality flags of other parameters for 
               these samples but conversions from /liter to /kg are suspect.
            9. Made new exchange file for Bottle data.
            10. Checked new bottle file with Java Ocean Atlas.
            

            
DATE        CONTACT       DATA TYPE              ACTION SUMMARY
----------  ------------  ---------------------  -----------------------------------------
2004-02-13  Anderson      CTD                    WOCE formatted/Online
            Sharon Escher noted that the value in the RECORDS=  field was 
              sometimes incorrect.  In checking this I discovered that almost 
              every station had ^Z as the last record.  A few stations also had 
              a record at the end that just had zeros except for the QUALT1 
              field, which had values.  I deleted these records and corrected 
              the value in the RECORDS= field when necessary. 
            Station 899 data between 4583.0 and 4653.0db was repeated at the 
              end.  I deleted the duplicate levels.  
            Station 941 had a date of 092295 in the ctd file, and 092395 in 
              the.sum file.  I changed the ctd file to agree with the sum file.
            Oxygen was in ml/l.  I converted to umol/kg.
            Station 870 and 871 had negative oxygens that I changed to 0.00 
              re J. Swift.
                                       PRESS    OXYGEN    
                             Sta. 870  25.0    -0.407 
                                       27.0    -0.439 
                                       29.0    -0.236  
                             Sta. 871  33.0    -0.260 
            Changed file names from xxx.CTD to i01wxxxx.wct.
            Had to remove COR DEPTH from .sum header in order to get the 
              exchange program to work. 
            
2005-01-10  Key           Cruise Report                C14 Report Submitted 
            The U.S. WOCE Indian Ocean Survey consisted of 9 cruises 
            covering the period December 1,1994 to January 22,1996.All of the 
            cruises used the R/V Knorr operated by the Woods Hole 
            Oceanographic Institute. A total of 1244 hydrographic stations 
            were occupied with radiocarbon sampling on 366 stations.
            
2005-02-18  Anderson      HELIUM/NEON            Data online
            i01e and i01w   
            Found file i1he.txt in 
              .../indian/i01/i01/original/2000.10.04_I1_BOTTLE. This file 
              contains the deep DELHE3, HELIUM, NEON, DELHER, HELIER, and NEONER 
              for i01e and i01w.
            I merged these parameters into the online files, and made new 
              exchangeand netcdf files.  There were no Q1 or Q2 flags so I set 
              them to 2.
            
2005-05-06  Anderson      CTD                    sta 882 O2 changed to µmol/kg
            As noted by Sharon Escher, sta. 882 was missing from the ctd 
            stations. I converted the oxygen to umol/kg on sta 882, added it 
            to the ctd .zip file, made new exchange and netcdf files and put 
            all files online.
            
2005-05-11  Reid          NUTs                   Update Needed, various anomolies
            I've finally had a chance to look at the Indian Ocean (I1W) 
              data.
            We noted in our cruise report that Niskin 7 at Stn 910 was an 
              obvious leaker and that the nutrients were flagged as 4.  I'm 
              pretty sure that's the 3793 dbar bottle.
            I don't know why the nutrients aren't flagged, as my notes say 
              they were.
            Re the odd deep nutrients at Stn 859: The original at-sea 
              calculation of those nutrients was made incorrectly, using the 
              wrong values for the standard concentrations. They were 
              recalculated post-cruise and look as though they will fit within 
              the envelopes of the property plots from the other Red Sea 
              stations.  Again, I don't know why the corrected version wasn't 
              part of the final data set.
            I will dig out or create a digital version of stn 859 and send it 
              to you, hopefully before the end of the week.
            
2005-05-11  Reid          NUTs                   Follow-up on previous note
            I found our Zipped data files and will attach a text file with 
              the data from I1W Stn 859. The nutrient data matches the paper 
              listing of the recalculated version that I found yesterday.
            Could you let us know if this version agrees with the other Red 
              Sea data? (It looks like it will.) Once I hear from you, I'll send 
              the correct data to the WHPO and others.
            
2005-06-13  Anderson       NUTs                  WOCE/Exchange/NetCDF files onlie
            i01w   316N145_11 
            Made changes to SILCAT, NITRAT, NITRIT, and PHSPHT on sta. 859 re 
            Joe Jennings.  Put corrected file online, made new exchange and 
            netcdf files.
            
2008-06-17  Kappa         Cruise Report          Added C14 & CO2 reports & Data Processing Notes
            Added these WOCE/CCHDO Data Processing Notes
            Added 4 reports to pdf and text versions of cruise report:
            1) Carbon Dioxide, Hydrographic and Chemical Data 
            2) Coulometric Total Carbon Dioxide Analysis
            3) Assessment of the Quality of the Shipboard Measurements of 
               Total Alkalinity
            4) Anthropogenic CO2 Inventory
            5) U.S. Woce Indian Ocean Survey: Final Report for Radiocarbon

