


     EP3-93-DI
     NOAA Ship Discoverer
     San Diego - San Diego
     August 23 - September 18, 1993

     Chief Scientist: L. Mangum 
     Survey Department: CST Murray, MacElroy, Betzler, O'Keefe, Davis
     CTD Personnel: L. Mangum
     Final Processing: M. Swapp and K. McTaggart


     ACQUISITION:

     A total of 41 CTD casts were taken along 95W and 110W during leg 1 of 
     the fall EPOCS cruise using PMEL Neil Brown CTD s/n 1114 and 12-bottle 
     rosette sampling package.  The majority of the casts were taken to a 
     depth of 1000 meters.  Two were to only 500 m and one was a deep cast.

     Typically 12 bottles were fired on each cast and salinity samples were 
     taken for calibration checks of the NBIS CTD.  Survey department personnel
     under the supervision of L. Mangum were responsible for preparing the CTD,
     all data acquisition, collection of water samples, and analyzing the 
     samples for salinity using the ship's Autosal.  The CTD data were collected
     on PMEL's shipboard acquisition system, consisting of a Zenith PC with 
     EG&G acquisition software.  

     
     CONDUCTIVITY CALIBRATIONS:

     A .CAL file was created at sea from CTD cast logs using program CALDSKW.
     Where CTD and bottle salinities differed greatly, a 60 scan average 
     salinity value from EG&G .BTL file replaced the cast log value if it made
     an improvement.  Pre-cruise calibrations (NRCC August, 1993) were used
     in CALIB.DAT for temperature and pressure coefficients.  Conductivity 
     coefficients came from LINCALW applying a linear fit over all bottles
     from both EP393 and EP493 cruises, excluding cast 32 bottles greater 
     than 1000 db.  Note no samples were taken during cast 38 owing to a deck
     unit malfunction.

     CALIB.DAT precruise calibrations for CTD used:

     1114    6  380
     -31.33027   .9964779  0.740232E-6  -0.420914E-10    P DN  S/N 1114  AUG 93
     -33.06427   .9928080  0.227357E-5  -0.187309E-09    P UP  S/N 1114  AUG 93
      -0.00211   .9997917  0.000000E-6   0.000000E-10    T 68  S/N 1114  AUG 93
      -0.03060   .9983487  0.000000E-6   0.000000E-10    C     S/N 1114  AUG 93
     
     Results of LINCALW:

         	A0 =  0.2380314E-02
         	A1 =  0.9993364E+00
         	max residual = -0.0127
         	std error = 0.0046 (64/510 discarded in 15 reps)


     CONDUCTIVITY CALIBRATION PROGRAMS & PPLUS COMMAND FILES:

     CALDSKW - creates .CAL uncalibrated data file on SCS system
     CALMSTRW - inputs .CAL uncalibrated data file
              - outputs .CLB calibrated data file (from .COM), and
                .SEA calibrated WOCE data file (edit quality bytes)
     LINCALW - inputs .CAL uncalibrated data file (may be broken into 
               groups), applies a linear fit to the data and throws out
               any points greater than 2.8 times the standard deviation,
               iterates through the program until no points are thrown out
	       outputs .COEF file containing linear fit coefficients and
	       .LOG file of fit iterations 
     CALMCONW.PPC - reads .CLB calibrated bottle data file and makes five
                    separate scatter plots: P, T, C, S, and cast number vs. 
                    delta-C (CTD-bottle).  These are examined for cast
                    breaks and drifts in the CTD.
     CALMDEEPW.PPC - reads .CLB calibrated bottle data file and makes two
                     separate scatter plots: CTD salinity and bottle salinity
                     vs. potential temperature from theta=0.6 to 2.2 C.
     DEEPCTD.PPC - reads .CTD EPIC pointer file and .BOT EPIC pointer file 
                   of deep casts only and overplots the bottle salinity 
	           data and CTD salintiy trace from theta=.8 to 2.4 C for 
	           each deep cast.


     PROCESSING: 

     Raw data files were restored from Mountain tapes and/or TK50 tapes to 
     the VAX at PMEL.  Standard processing programs with default parameters
     were used to reduce these data.  Single point spikes were removed from
     casts 1, 20, and 39 using NOMIT subroutine in EPCTDW.  Cast 32 was
     truncated at 1000 db.

     Final CTD and bottle files were moved to DISK$HAYES and included in the
     RIM data management tables on December 18, 1995.

     DPDNZ - inputs EG&G .EDT raw data file
           - outputs .DPZ binary file including computed fall rates and
             .RECZ ASCII file to choose downcast record range from
     DLAGZ - inputs .DPZ binary file, applies precruise calibrations from 
             CALIB.DAT, edits data for window outliers (according to 
             WINDOW.DAT) and first differencing outliers, fills gaps by
             linear interpolation, lags conductivity, edits data exceeding
             fall rate criteria (according to .INP created by DLAGAVZ.COM;
             default minimum fall rate acceptable is .8 db/60 scans (25
             meters per minute) and pressure interval of 1.5 db; doesn't 
             fill these gaps), computes 1-meter averages, and applies cell 
             dependence to final conductivity values
           - outputs CTDERR.DAT file of outlier flags, interpolated values,
             and fall rate criteria failures, and an ASCII .CTD data file
             including computed salinity
     EPCTDW - inputs .CTD calibrated P, T, OXC, OXT, and raw conductivity;
              applies any additional P and T cals (in EPCTDW_SHIP.COM),
              corrects raw C for cell factor, and applies C cals from
              EPCTDW_SHIP.COM; computes salinity; deals with oxygen if 
              there was a sensor; eliminates 1-point spikes according to
              the gradients hardwired into the source code; omits any 
              values for manual despiking; fills by linear interpolation
              for a value to exist every whole meter; recomputes C from
              S; and calculates ITS-90 temperature and other EPIC variables.
            - outputs final .CTD data file in EPIC format, and a .LOG
              file listing editted and filled data points 
     EPICBOMSTRW - inputs .CLB calibrated bottle data file and
                   .CTD EPIC data files (for header information)
                 - outputs .BOT bottle data files in EPIC format
     TSPLTEP.PPC - reads .CTD EPIC pointer file and .BOT EPIC pointer file
                   and overplots full water column bottle salinity and CTD 
                   trace as well as sigma-t lines (from SIGMAT.DAT). Use
	           TSPLTB.PPC to include oxygen data.  
     TEXTNOX - inputs .CTD EPIC pointer file and constructs PPLUS subcommand
               files
	     - outputs TXT*.PPC files containing %label commands for table
	       listings for each cast
     3PLTNOX.PPC - reads TXT*.PPC subcommand files and .CTD EPIC pointer
                   file and overplots vertical profiles of temperature, 
	           salinity, and sigma-t vs. pressure to 1000 db on left-
	           hand side of page; and lists data in table form on 
	           right-hand side of page.  Use 4PLT1DB.PPC to include 
	           oxygen data.
