                        Cruise Report of the 2017
                     reoccupation of the GO-SHIP A02
                   section by the RV Celtic Explorer,
                            Ireland (CE17007)



                             Project Summary

          Section Name  A02         
              Expocode  CE17007  
       Chief Scientist  Peter Croot 
Principal Investigator  Evin McGovern 
                 Dates  27 April 2017 to 22 May 2017 
         Ports of call  St John's, Canada to Galway, Ireland 
     Stations occupied  58 on A02 line 
    Equipment deployed  1 Argo float 
 
 
This is the cruise report of the GO-SHIP A02 repeat hydrography 
expedition carried out by the RV Celtic Explorer (CE17007) in April-May 
2017. The opinions expressed in this report are only those of the 
authors. 
 

Author:  
Prof. Peter Croot                         Tel: +353 91 49 2194 
Earth and Ocean Sciences                  email: peter.croot@nuigalway.ie 
School of Natural Sciences and the Ryan Institute 
National University of Ireland Galway 
University Road 
Galway H91 TK33 
Ireland 
 
 
           
  
 
 

Table of Contents 

1.  SUMMARY 

2.  RESEARCH PROGRAM AND PROJECT OVERVIEW 
    2.1.  INFORMATION ON THE GO-SHIP REPEAT HYDROGRAPHY PROGRAM  
    2.2.  ATLANTIC OCEAN COOPERATION - THE GALWAY STATEMENT  
    2.3.  PREVIOUS OCCUPATIONS OF THE A02 SECTION 

3.   NARRATIVE OF THE CRUISE 

4.  PRELIMINARY RESULTS - WATER COLUMN PARAMETERS 
    4.1.  CONDUCTIVITY TEMPERATURE DEPTH (CTD) HYDROGRAPHY 
    4.2.  LOWERED ACOUSTIC DOPPLER CURRENT PROFILER (LADCP) 
    4.3.  CHLOROFLUOROCARBONS (CFCS)
    4.4.  DISSOLVED OXYGEN 
    4.5.  NUTRIENTS (NITRATE, NITRITE, PHOSPHATE AND SILICATE) 
    4.6.  CARBON SYSTEM PARAMETERS 
    4.7.  δ13C DISSOLVED INORGANIC CARBON (DIC) 

5.  PRELIMINARY RESULTS - UNDERWAY MEASUREMENTS 
    5.1.  METEOROLOGICAL DATA 
    5.2.  THERMOSALINOGRAPH DATA 
    5.3.  SHIPBOARD ADCP 
    5.4.  UNDERWAY PCO2 MEASUREMENTS (GO-8050 MARINE INSTITUTE)  
    5.5.  REPORT OF UNDERWAY DATA (GO-SHIP CELTIC EXPLORER - 2ND LEG) 

6.  STATION CATALOGUE CE17007 

7.  SHIPBOARD PARTICIPANTS 

8.  DATA AND SAMPLE STORAGE AND AVAILABILITY  

9.  ACKNOWLEDGMENTS 
  

  


1.  SUMMARY 
 

During CE17007, a combined chemical and physical oceanography research 
expedition reoccupied the existing A02 section in the North Atlantic as a 
contribution to the international GO-SHIP program. This expedition marked 
the first time that Ireland had organized and performed a major 
international hydrographic study. The work was performed in cooperation 
with international teams from Canada, Denmark, Germany, the United 
Kingdom and the United States of America.    

The measurements made along the A02 repeat hydrography section included 
hydrographic measurements (CTD-rosette, Lowered and shipboard ADCP 
measurements) as well as freon, oxygen, nutrient and carbon system 
measurements. Bad weather encountered during the expedition resulted in 
us unfortunately having to omit 9 of the 67 planned CTD stations, however 
58 full depth stations were occupied during the 2017 survey. All GO-SHIP 
level 1 parameter measurements were performed as planned and have 
contributed to a valuable data set for this important repeat hydrography 
section in the North Atlantic.  
 
 
 
 
 
2. RESEARCH PROGRAM AND PROJECT OVERVIEW 
 

Hydrographic measurements were made along the A02 section in April-May 
2017 under the direction of the Global Ocean Ship-Based Hydrographic 
Investigation Program (GO-SHIP). This reoccupation of the A02 section was 
supported by the Irish Marine Institute and funded under the Marine 
Research Programme by the Irish Government. Individual teams were 
supported by the European Union’s Horizon 2020 and the Canada Excellence 
Research Chair in Ocean Science and Technology (see section 9 for full 
details).  
 


2.1.  Information on the GO-SHIP repeat hydrography program 
 
GO-SHIP (www.goship.org) is an international program which addresses the 
ongoing requirement to monitor inventories and transports of CO2, 
nutrients, heat and freshwater in the ocean. In essence, the vital signs 
of the ocean system. The program provides measurements to assess the 
long-term changes and variability in marine biogeochemical and physical 
processes in response to natural and human-induced forcing. It does this 
by providing unique high-quality measurements of key oceanographic 
parameters at all ocean depths. These measurements have become the 
cornerstone of several major efforts to quantify long-term changes and 
decadal variability in ocean properties and are critical for calibrating 
and validating other observation and modelling programs. Earlier programs 
under the Joint Global Ocean Flux Study (JGOFS), World Ocean Circulation 
Experiment (WOCE), and Climate Variability and predictability (CLIVAR) 
programs provided an approximately decadal set of observations on 
hydrographic lines, including the A02 line that this GO-SHIP expedition 
builds upon. Examples of critical findings made possible by decadal 
measurements include ongoing ocean uptake and subsurface storage of 
anthropogenic CO2 with consequent ocean acidification, ongoing warming 
and freshening of the deepest bottom waters, and accelerated overturning 
of intermediate depth water masses in the Southern Ocean. The Repeat 
Hydrography Program provides a robust observational framework to monitor 
these long-term trends. 

Continuation of these programs under GO-SHIP involves reoccupying the 
same set of hydrographic transects spanning the global ocean with full 
water column measurements. These measurements are in support of: 

• Model calibration and validation 
• Studies of ocean circulation 
• Carbon system studies 
• Heat and freshwater storage and flux studies 
• Changes in volumes and properties of water masses 
• Quantification of turnover timescales 
• Calibration of autonomous sensors and satellites 


 
 
2.2.  Atlantic Ocean cooperation - the Galway statement 
 
Atlantic Ocean cooperation - the Galway statement 

Galway was the location where the European Union and the governments of 
Canada and the USA agreed a new alliance for Atlantic Ocean Research 
Alliance (AORA). The Galway Statement on Atlantic Cooperation signed in 
May 2013 by the 3 parties recognises that ocean observation is 
fundamental to understanding the ocean and forecasting its future and 
aims to align observation efforts to improve ocean health and promote 
sustainable management. In this manner the EU Horizon 2020 project 
AtlantOS supports and builds on the aims of the Galway Statement and 
other Atlantic basin initiatives, including Canada’s recently funded Ocean Frontier Institute. The international Atlantic-wide partnerships in 
AtlantOS are working to innovate, improve and enhance the existing 
integrated Atlantic Ocean Observing System. The GO-SHIP A02 transatlantic 
survey carried out over 27 days in April-May 2017, was accomplished 
through the cooperative approach envisaged in the Galway Statement. 
Our GO-SHIP expedition is an international collaboration between Ireland, 
Canada, Germany, the U.S.A. and the U.K. and is a clear example of the 
ongoing spirit and commitment to the Galway agreement signed in May 2013 
by the E.U., Canada and the U.S.A in which all 3 parties recognised the 
mutual benefits of Atlantic Ocean Cooperation. This expedition also puts 
Ireland’s marine research into focus on a global stage and demonstrates 
that Ireland has the capacity through the RV Celtic Explorer and its own 
marine scientists to undertake key works of international importance and 
not just of local interest to Ireland. This is an exciting time then for 
Marine Research in Ireland, with new marine geoscience work on marine 
acoustics, geophysics, biogeochemistry and remote sensing being conducted 
on the west coast of Ireland under the framework of the SFI funded 
research centre iCRAG (Irish Centre for Research in Applied Geoscience). 
 


2.3.  Previous occupations of the A02 section 
 
The A02 section crosses both basins of the North Atlantic and it was 
originally called the "48N"-section (WOCE/A2 and AR19) and runs from the 
edge of the Grand Banks (at a bottom depth of 65 m) to the Celtic shelf 
south of Ireland (at a bottom depth of 155 m) nominally along 48N. The 
section was first occupied in 1957 and then again in 1982, subsequently 
during the WOCE and CLIVAR era there were several more occupations of the 
high-density, full-depth section carried out (see Table below). In recent 
years the western end of the A02 section has been sampled annually by 
German researchers examining changes in deep water formation via the 
measurement of CFC’s. A full occupation of the A02 line for carbon system 
parameters had not been made since 2002. Work performed on the A02 line 
20 years earlier was some of the first in the world to clearly show the 
uptake of anthropogenic carbon by the ocean.  
  

Table 2.1: Previous Occupations along the A02 line 
 
Cruise date  Research vessel  Cruise      O2  Nuts  SADCP  LADCP  CFC  He  CO2   δ13C  14C  Comments 
(Year/month)                  identifier   
———————————  ———————————————  ——————————  ——  ————  —————  —————  ———  ——  ———  —————  ———  ————————————————
1957         Discovery                    x    x                                  
1982/04-/05  Hudson           82-002      x    x                                  
1993/07Я08   Gauss            G226        x    x                                  
1994/10      Hudson           18HU94030   x    x                   x        x               Only west of 42W 
1994/10Я11   Meteor           M30/2       x    x      x            x   x    x          x      
1995/04Я05   Hudson           18HU95003   x    x      x      x     x        x               Only west of 42W 
1996/05Я06   Gauss            G276        x    x                                   
1997/06      Meteor           M39/3       x    x      x      x     x        x           
1998/05      Gauss            G316/1      x    x                                   
1999/07Я08   Meteor           M45/3       x    x      x      x     x   x    x     x         Only west of 41W 
2000/05Я06   Gauss            G350/1      x    x      x      x              x           
2001/05      Meteor           M50/1       x    x      x      x     x        x               Only west of 30W 
2001/08      Meteor           M50/4       x    x      x      x     x   x    x               Only east of 28W 
2002/06      Gauss            G384/1      x    x      x      x              x           
2003/08      Meteor           M59/2       x    x      x      x     x        xa              
2003/09      Meteor           M59/3       xb          x      x     x                        Only west of 30W 
2005/06      Thalassa         SUBPOLAR    xb          x      x     x                        Only east of 31W 
2005/07Я08   Thalassa         WNA         xb          x      x     x                        Only west of 30W 
2007/04      Maria S. Merian  MSM-05/1    xb          x      x     x                        Only west of 33W 
2008/07-/08  Maria S. Merian  MSM-09/1                x      x     x                        Only west of 30W 
2009/07-/08  Maria S. Merian  MSM-12/3    xc          x      x     x        xc    xc        Only west of 30W 
2010/08-/09  Meteor           M82/2       xb          x      x     x                  
2011/06-/08  Meteor           M85/1       xb          x      x     x              xd   xd      
2012/06-/07  Maria S. Merian  MSM-21/2                x      x     x                        Only west of 30W       
2013/05-/06  Maria S. Merian  MSM-28      xb          x      x     x                  
2014/05-/06  Maria S. Merian  MSM-38      xb          x      x     x              xe        Only west of 30W     
2015/05-/06  Maria S. Merian  MSM-43      xb          x      x     x   xf                   Only west of 30W      
2016/03-/05  Maria S. Merian  MSM-53      xb          x      x     x                
2017/04-/05  Celtic Explorer  CE17007     x    x      x      x     x        x     x         GOSHIP A02  
2017/05-/06  Maria S. Merian  MSM-64      xb          x      x     x              xg         
   
  
All expeditions made CTD and salinity measurements, though station 
spacing may be considerably different.  

Meteor 45-3 includes pH measurements. 

(a) Samples for δ13C DIC taken also. 
(b) No nutrient samples taken. 
(c) Samples for nutrients, DIC, alkalinity and δ13C taken for later 
    analysis (no dataset found in Pangaea). 
(d) Cruise report indicates samples were taken for δ13C and δ14C DIC as 
    part of GEOTRACES-NL (S. van Heuven). 
(e) Samples for δ13C taken for later analysis (MARUM). 
(f) He samples were made during the expedition but not along the A02 
    line. 
(g) Samples for δ13C taken for later analysis (MARUM).





3. NARRATIVE OF THE CRUISE  


The Celtic Explorer was ready to depart St John's in the evening of April 
27th for CE17007 as planned, after a relatively smooth arrival of 
participants and vessel into Canada.  

The majority of the laboratory containers to be used during CE17007 had 
been loaded on the Celtic Explorer prior to leaving Galway, this included 
the CFC container from GEOMAR, the CO2 analysis van from the University 
of Exeter and the Nutrient lab from the Marine Institute (container on 
loan from NIOZ). The arrangement of the laboratory containers deployed on 
the working deck of the vessel had to be revised in St Johns from what 
was initially planned as when the Canadian container was loaded on in St 
Johns, it’s intended location would have seen it block the external air 
vent of one of the other lab containers. A new optimal configuration of 
the container of the work deck was found and the laboratory containers 
were loaded and connected to water and electrical services well in time 
for the scheduled departure time. The flooring of the MI container was 
slightly damaged during mobilization but was deemed still suitable for 
use. 

There was also time to give a quick tour of the ship to Jim Kelly, 
Ireland's ambassador to Canada, and introduce him to the work that was to 
be done during this expedition. Canadian colleagues also took the 
opportunity to visit the vessel at this time, including Prof. Brad de 
Young from Memorial University in St John’s and Prof. Doug Wallace from 
Dalhousie University whose research group was participating in this 
expedition. 

Unfortunately, one of the scientific participants, part of GEOMAR’s CFC 
team, had felt unwell while travelling to Canada and had been 
subsequently diagnosed by medical staff at a hospital in St John’s on the 
day before the scheduled departure as suffering from acute Bronchitis. 
The medical opinion provided was that they were likely to improve with 
bed rest and medication, thus the decision was therefore taken to delay 
departure from St John’s until the morning of the 28th of April and to 
reassess their condition, regarding, if they should sail with us or 
remain in St John’s for further medical treatment.  After a good night’s 
sleep in the ship’s hospital, the scientist in question was significantly 
improved in condition, that it was felt they could remain onboard and be 
given time to fully recover before starting work at sea. The rationale 
behind this was that we may miss some initial stations for CFCs while he 
was recovering but we would still be able to sample and measure CFCs at 
some point during the expedition. The ship then made final preparations 
to leave St John’s at 9 am (St John’s time) that morning.  

The passage from St John’s to the first station was slow at first due to 
dense fog and the necessity to be watchful for ice bergs near St John’s, 
however after 29 hours we arrived at our initial station on the Grand 
Banks. During the steaming time to the first station, the internal 
springs on the new Niskin bottles, purchased especially for this 
expedition, had to be adapted as there was insufficient spring tension, 
this was accomplished by shortening the springs by doubling them back. 
Thanks to Marshall Swartz and Tom Gilmartin for their help with this. 

The CTD deployment at the first station went well (April 29), with only a 
single bottle, number 15, failing to fire. Water sampling from the CTD at 
the first station went smoothly, with all of the groups having done a 
good deal of preparation before with regard to keeping to the assigned 
sampling order, preventing overcrowding around the CTD and maintaining 
safe working practice throughout. The sampling of the first station 
involved all participating groups, apart from the CFC group (as indicated 
earlier).   

During this expedition, the standard CTD procedures onboard the Celtic 
Explorer were followed, this includes when recovering the CTD to lower it 
onto a mat on the deck and then securing the CTD to the gunwales or other 
parts of the ship’s superstructure via cables, extra care therefore had to 
be taken then for those sampling around the CTD and walking to and from 
the container labs at the aft due to the presence of the cables.  It is 
suggested that for future work that an eye hole be fitted in the deck so 
that the CTD can be directly secured to the deck and avoid this problem 
with the cables.   

Work continued quickly across the shelf with 6 stations sampled on April 
30 as everyone got quickly into their work and the outside temperature 
warmed up as we transited from the cold shelf waters to the Gulf stream.  
The SBE43 oxygen sensor (SN 3339, last calibrated 16 Feb 2017) was 
switched out of the CTD sensor package and replace with an identical unit 
(SN 1416, last calibrated 18 Mar 2017) after station 3 as it was 
displaying erratic behaviour.  

The CTD winch had been working well in continental shelf waters, however 
as the ship moved into deeper waters (> 2500 m), and the ship began to 
roll more, a problem developed with the heave compensator of the winch, 
by which the springs became overloaded (fully squeezed), would then 
suddenly release, making a dramatic noise but more importantly creating 
high tension in the CTD cable resulting in poor spooling on or off the 
drum.  The crew were excellent in managing this issue as best as possible 
and were able to manually realign the spooling throughout the up cast 
when required. However overall this lengthened the time required for 
winch operations from that originally planned, and achieved on the shelf, 
as both down and up cast spooling rates had to be slowed appreciably.  
Even with these precautions in place, it was noticeable that in heavy 
swell conditions, that the CTD acquisition and LADCP data indicated 
appreciable vertical acceleration of up to 1.5 m s-2. The presence of an 
inline tensiometer logging system would have helped here to provide the 
scientists and crew regarding the strain on the CTD wire and at what 
depths it had occurred. This issue with the heave compensator had 
apparently not arisen before during CTD operations, as previously the CTD 
wire had rarely been deployed deeper than 3000 m and not since 2014.  

As the expedition made its way into the Gulf stream proper with 
subsequent higher current velocities, it was noticeable that when on 
station the vessel’s dynamic positioning system was having trouble to 
maintain position and maintain a good wire angle. This was aggravated by 
the heavy swell encountered at this time making deployment and handling 
of the CTD difficult. The combination of these factors resulted in the 
ship drifting off station over the course of the occupation and there 
being a large difference between the wire out and the CTD depth. This 
resulted in much longer station times than planned and progress was much 
reduced from May 1-4.  

At station 11 (May 3), there was a problem with the firing of the bottles 
due to a communication problem with the CTD at 1500 m on the up cast and 
the cast was repeated.  During the subsequent deployment the bottle 
firing mechanism failed again, and a bird cage kink was found on the wire 
which required cutting off 300m of sea cable and retermination. The cable 
was checked onboard prior to redeployment and was found to be working 
fine. 

Over the next 24 hours, 3 more stations were run without major incident 
(Stations 12-14) despite increasing wind and swell conditions.  

On May 5, the weather conditions had unfortunately deteriorated further 
and the planned station 15 had to be abandoned when the CTD was at 1500 m 
due to increasing wind (Figure 3.1) and swell making operation of the 
equipment unsuitable. The high wind and sea state prevented reoccupation 
of this station again the following day and the ship was forced to heave 
to until the storm system had passed and the swell abated. On the morning 
of May 7, we attempted to occupy station 16 (UTC 07:00) however the 
weather conditions proved too rough to deploy the CTD, so the ship then 
progressed to station 17 (UTC 14:40) but again the sea state prevented 
occupation of the station. The safe operating window for station work was 
now clearly defined by the wind and sea state, with no operations 
permissible at Beaufort 7 or above (28-33 knots, swell > 4m). The 
decision was then made to bypass stations 18 and 19 and resume sampling 
at station 20 in the evening of May 8. As weather conditions improved 3 
more stations (21-23) were completed on May 9.  
 

Figure 3.1: Wind speed observed by the ship’s metrological sensors during 
            the period May 4 - May 13, 2017.  


At station 23 an incident occurred during the downcast, when at 1100 m, 
it was observed that the seabird software indicated bottle number 1 had 
closed on deck prior to deployment. The cast was retrieved in order to 
prevent implosion of the bottle, but on its return to the surface bottle 
number 1 was found to be still open. The cast was rerun without any 
further incident. However during the next station (24) there were further 
problems firing the bottles on the upcast, where bottles fired without 
being triggered, the CTD was returned to the surface and underwent a full 
check of the firing mechanism on deck where upon a small paint chip was 
found in the firing mechanism at this time and it is likely, though not 
definitely confirmed, that was this the cause of the problems. The cast 
was rerun without any further incident. 

One bright note at this time was the introduction to the sampling team at 
station 23 of the GEOMAR team sampling for CFC’s as they were now able to 
analyse samples after a team effort between scientists and crew to 
construct an improvised cooling system following a breakage of the GC-
instruments cooling system.   

At station 27 (May 11) a problem was encountered during the initial 
stages of the downcast with large differences observed between the 
primary and the secondary temperature and conductivity sensors, this 
resolved itself and was likely a partial blockage of the CTD pump in the 
primary channel. The system was checked prior to the next deployment. At 
the next station (28) temperature and salinity data indicated the 
presence of a cold core cyclonic eddy. Subsequent analysis of AVISO and 
shipboard ADCP data appeared to confirm this.    

On May 12th with a further storm system forecast to follow us from the 
west and generate significant wind and swell, the decision was made to 
skip alternate stations to try and position ourselves further east of the 
storm system and allow us to optimise the amount of time with good 
working available to us to complete stations in the eastern basin. 
Stations 30, 32, 34, 36 and 38 were thus omitted from the sampling 
program due to time constraints.   

Routine maintenance was carried out on the Niskin bottles after station 
33 (May 13: 0200 UTC) in response to comments returned by the sampling 
group. The spigots were checked on all bottles (3 had been reported as 
difficult to open), the outer flange was removed, the valve body was 
taken out, the 2 inner o-rings were lifted and put back in, pushed 
inside, and then the reinstalled flange. No changes of parts were made.  

During the next week, good weather with light winds saw the sampling 
program get back into full swing and no significant further issues arose 
resulting in excellent progress as we made our way through the eastern 
basin. SHALLOW (0-150 m) plankton net tows were made at several stations 
in the central part of the section as part of a Marine Institute study 
into the dinoflagellate species Azadinium. Deep water samples were taken 
in the eastern basin at stations 58 and 60 for an international δ13C 
intercomparison organized by the group from Dalhousie. An ARGO float (S/N 
7842: ARGO code 6901926) was successfully launched for the Marine 
Institute at station 60 (48 53.394, 13 43.506) on the morning of May 20. 
The final CTD station (67) was completed on the morning of May 21st and 
the vessel then proceeded north to the coast of Ireland. 


Figure 3.2: Cruise Track (orange) and location of completed stations (red 
            circles) during CE17007. 


On May 23rd the expedition sighted the Irish coast with good view of the 
Clare coastline and the cliffs of Moher and the Aran islands, and the 
Celtic Explorer entered Galway Bay and then as high tide approached the 
final progression was made into Galway Harbour under the watchful eye of 
a traditional Galway Hooker. 

The Canadian ambassador to Ireland, Kevin Vickers, was also a welcome 
guest to the RV Celtic Explorer at the end of the Voyage and we were able 
to update him on what we had encountered and accomplished during the 
transit 

Overall the main objectives of the expedition were achieved, as full 
water column sampling took place at 58 of the 67 planned stations; 
resulting in 85% coverage of the section for the hydrography, nutrients 
and LADCP. The entire section was completed in terms of the shipboard 
ADCP track.  
 
  



4.  PRELIMINARY RESULTS - WATER COLUMN PARAMETERS 


4.1. Conductivity Temperature Depth (CTD) Hydrography  
     (Peter Croot, Caroline Cusack and Marshall Swartz) 


The main workhorse of CE17007 was the Seabird SBE911plus CTD connected to 
a SBE32 carousel. Power to the CTD and sensors was provided through the 
sea cable from an SBE11plus deck unit located in the dry lab in the ship. 
The sensor setup employed during CE17007 is located below in Table 4.1. 


Table 4.1: Sensor setup on CTD for CE17007 


Sensor Code     Parameter            Serial Number    Calibration/
                                                      Service date 
——————————————  ———————————————————  ———————————————  —————————————————
CTD SBE911                           09P19835-0513    M: 10 Nov 2014   
  plus PSO513                                         POMs: 25 Jan 2015 

SBE32           Bottle firing        unknown          unknown 
                mechanism    

SBE3            T1: Primary          4023             01 Sep 2016 
                Temperature Sensor    

SBE3            T2: Secondary        4927             28 Sep 2016 
                Temperature Sensor    
                    
SBE35           Discrete depth       0020             17 Oct 2016 
                bottle triggered
                Temperature sensor  

SBE4            C1: Primary          3480             20 Sep 2016 
                Conductivity Sensor    

SBE4            C2: Primary          2764             06 Oct 2016 
                Conductivity Sensor    

SBE43           Oxygen Sensor(1)     3339             16 Feb 2017 

SBE43           Oxygen Sensor(1)     1416             18 Mar 2017 

VA500           Altimeter            46504            unknown 

Wetlabs C-star  Transmissometer      CST-1101DR       08 Dec 2016 

Wetlabs ECO-    Fluorometer and      1609             12 Oct 2009    
  FLNTURTD        Turbidity    
———————————————————————————————————————————————————————————————————————
(1) The original oxygen sensor (S/N 3339) was found to be performing 
    poorly at station 3 and was swapped out for a replacement sensor 
    (S/N 1416). 


The CTD supplied a standard SBE-format data stream at a rate of 24 Hz. 
The CTD provided pressure plus dual temperature and conductivity data, 
with single sensors for oxygen, optical transmission, a combined 
fluorometry/turbidity sensor and an altimeter. The CTD system was 
equipped with dual pumps. Primary temperature, conductivity and dissolved 
oxygen were plumbed into one pump circuit; and the secondary temperature 
and conductivity was on the other circuit. A Lowered Acoustic Doppler 
Profiler (LADCP) was also mounted on the rosette frame; it was powered 
separately and collected data internally. The original altimeter from 
this unit (Benthos) was swapped with a Valeport VA500 on loan from WHOI 
as the LADCP interferes with the Benthos device.  Prior to every CTD 
deployment the transmissometer was checked and cleaned and a zero reading 
in air taken.  

The primary temperature and conductivity sensors were used for reported 
CTD temperatures and salinities on all casts; the exception was station 
27, were there was an initial problem with the primary signal, as 
evidenced by anomalously low O2 readings and significant deviations from 
the values of secondary temperature and conductivity sensors, due to what 
is suspected was a transient pump blockage.  

There were a number of issues that arose with the safe operation of the 
CTD winch system under heavy seas during this expedition and details on 
this can be found above in the narrative of the cruise. The rest of this 
section deals with issues that arose with the CTD system itself and not 
the operation and spooling on and off the winch.  

At station 11 the pump stopped and started intermittently. Bottom 
connection warning alarm triggered a couple of times. Bottle firing 
communication error occurred. Water ingress on secondary pump connector, 
loose connections were tightened, the secondary pump was cleaned and the 
bottle firing mechanism was also cleaned.  

Retermination of the cable: The cut off section was measured and found to 
have an intermittent low resistance (<50 ohms) core to ground and was 
likely a cause of the modulo errors. The sea cable was electrically 
evaluated with the ship’s megohmmeter to test insulation integrity, and 
found to be >1000Megohms at 500VDC, passing the requirements. End to end 
continuity of the conductor was measured with a Fluke 112 in low 
resistance range, and found to be 32ohms steady, the value expected for 
this length of cable. 

The Ship’s Technician applied the normal re-usable mechanical termination 
to the new cable end, and then fabricated a new electrical termination 
using a ScotchCast 82F1 splice kit with 2131 Scotch resin, and reusing 
the 2m pigtail lead with MCIL2F connector and MCDLSF locking sleeve. 
After 3hr curing at 20°C, the splice kit shell was removed, inspected, 
found fully satisfactory and the termination was attached to the rosette. 
The system was tested again before the next station by running the 
SBE9/11/32 system with SeaSave to fire all mechanical release positions 
without attaching bottle lanyards. All systems operated as expected and 
system was then ready for next station. 

Routine maintenance was carried out on the Niskin bottles after station 
33 (May 13: 0200 UTC) in response to comments returned by the sampling 
group. The spigots were checked on all bottles (3 had been reported as 
difficult to open), the outer flange was removed, the valve body was 
taken out, the 2 inner o-rings were lifted and put back in, pushed 
inside, and then the reinstalled flange. No changes of parts were made.  

The CTD data and bottle trip files were acquired by SBE Seabird SeaSave 
V7 version 23.0.2 on the ship’s Windows 7 workstation located in the dry 
lab. Pre-cruise calibration data were applied to CTD Pressure, 
Temperature and Conductivity sensor data acquired at full 24 Hz 
resolution. Bottles were close on the upcast through the software and 
were tripped 30 seconds after stopping at the required bottle depth to 
allow the rosette wake to dissipate and the bottles to flush. The upcast 
continued 30 seconds after closing a bottle to ensure that stable CTD and 
reference temperature data (SBE35) were associated with the bottle trip.  

The performance of the sensors throughout the expedition was considered 
to be very good, as can be seen in figures 4.1 and 4.2 below. 

 
Figure 4.1: Histograms of the difference in temperature between the 
            primary, secondary and SBE 35 temperature sensors during 
            CE17007.  

Figure 4.2: Histogram of the difference in salinity between the value 
            calculated from the primary sensors and the measured 
            salinometer salinity (n = 1195, 15 values discarded as 
            clearly outliers using Grubb’s test).  


The comparison of the O2 data with the Winkler titration data is present 
later in this report. Data from the transmission sensor for the A02 
sections is shown below. An anomaly at station 41 just beyond the ridge 
crest is apparent in the data and is likely the result of 

something becoming lodged in the sensor at the time of deployment. 
Subsequent cleaning of the sensor prior to the next cast resulted in 
sensor performance returning to earlier pre station 41 values. 


Figure 4.3: %Transmission along the A02 section 


A screen shot of a computer  Description generated with high confidence

Of the derived variables commonly used in physical oceanography, 
potential vorticity is often employed as a tracer of water masses (Figure 
4.3). In the figure below it can the anomalous station 27 (pump problem) 
is also clearly evident.  


Figure 4.3: Potential vorticity along the A02 section. 


The data from the NTU and fluorescence sensor were not corrected for 
during this expedition and no calibrations of these sensors were 
performed at sea.  

 
4.2.  Lowered Acoustic Doppler Current Profiler (LADCP)  
      (Daniel J. Torres - on land, Marshall Swartz - shipboard) 


Voyage CE17007 of R/V Celtic Explorer was carried out from April 26 - May 
22, 2017 in the North Atlantic Ocean. The cruise was a multi-national 
collaboration between 8 institutions as part of the GO-SHIP program 
covering the A02 section. The primary purpose of the cruise was to 
conduct a basin scale high resolution hydrographic/tracer/velocity survey 
of the North Atlantic Ocean from St. Johns, Newfoundland, Canada to 
Galway, Ireland. The WHOI contribution to the program was to collect 
lowered ADCP data at each CTD station while assisting personnel from the 
Marine Institute of Ireland develop their own LADCP measurement 
capability. All the objectives were successfully met. 

 
Cruise Synopsis 

The cruise began in St. Johns, Newfoundland, Canada on April 26, 2017. 
The LADCP system consisted of a downward-facing Teledyne RD Instruments 
150 kHz ADCP, an upward facing 300 kHz ADCP, an external 48 Volt 
rechargeable lead-acid battery pack, and a Linux based data acquisition 
computer. Both ADCPs and battery pack were mounted on a Seabird SBE32 24 
10-liter bottle rosette. An extension stand for the frame was modified at 
WHOI to allow the mounting of the battery and downward facing ADCP. The 
SBE32 frame was modified at the Marine Institute in Ireland to allow 
mounting of the upward facing ADCP.  

A total of 67 CTD stations were sampled (see figure 1). Due to time 
constraints, stations 16 - 19 and 30, 32, 34, 36, and 38 were not sampled 
with the LADCP. At station 8, the downward facing ADCP had a beam 
failure. Since only 3 beams are needed to achieve good velocity 
measurements and a backup 150 kHz ADCP was not available for this cruise, 
that instrument was left on the frame for the remainder of the cruise. 
Also, at station 8, the upward facing 300 kHz ADCP was experiencing 
communication problems. So that instrument was swapped out for a spare. 
Those instruments successfully collected data for the remaining stations. 
A station log was kept noting specific details for each deployment. In 
order to post-process the LADCP data into absolute velocity profiles, CTD 
data were processed as a time series at 24 Hz for each station. Processed 
shipboard ADCP data were also made available (by another group) for LADCP 
post-processing. Raw LADCP data were provided to Andreas Thurnherr of 
LDEO for post-processing.  


Figure 4.2.1: LADCP Station locations 

 

4.3.  Chlorofluorocarbons (CFCs) 

 

4.3.1.  Measurements of CFC-12 and SF6  
        (B. Bogner, V. Merten, J. Bruckert, PI: T. Tanhua,) 

During the cruise a GAS CHROMATOGRAPH / PURGE-AND-TRAP (GC/PT) systems 
was used for the measurements of the transient tracers CFC-12 and SF6. 
The systems ҐT5Ӡwas a modified version of the set-up normally used for 
the analysis of CFCs (Bullister and Weiss, 1988). To cool the traps a 
system with refrigerated ethanol at -65°C was used. 

The first 22 stations the instrument wasn't ready because of illness of 
the lab technician and because important parts of the trap-cooling 
equipment broke down. With dedicated help by the ship’s crew and using the 
onboard -80°C freezer, we were able to start sampling every odd station 
from station 23 onward. Per station up to 18 depths were sampled, 
depending on freezer capacity, as it had trouble keeping the ethanol cold 
enough if measurement frequency was too high.  

The trap was 100 cm of 1/16" tubing packed with 70cm Heysep D.  The 
systems used a 1/8" packed main column consisting of 180 cm Carbograph 
1AC (60-80 mesh) and a 50 cm Molsieve 5A, heated up to 60°C. The tracers 
were trapped at -60 to -68°C; desorption at 120°C. The pre-column was 
packed with 20 cm Porasil C and 20cm Molsieve 5A in a 1/8" stainless 
steel column. Detection was performed on an Electron Capture Detector 
(ECD). This set-up allowed efficient analysis of SF5 and CFC-12.  

Samples were collected in 250 ml ground glass syringes. An aliquot of 
about 200 ml of the samples was injected into the analytical system. 
Standardization was performed by injecting small volumes of gaseous 
standard containing SF6 and CFC-12. This working standard was prepared by 
the company Dueste-Steiniger (Germany). The CFC-12 concentration in the 
standard has been calibrated vs. a reference standard obtained from R.F 
Weiss group at SIO, and the CFC-12 data are reported on the SIO98 scale. 
Another calibration of the working standard will take place in the lab 
after the cruise. Calibration curves were measured twice to characterize 
the non-linearity of the detector. Point calibrations were always 
performed between stations or every 15 samples to determine the short-
term drift in the detector. Replicate measurements were taken on a couple 
of stations depending on work load and freezer capacity. The determined 
values for precision and accuracy are listed in Table 4.3.1. 

A total of 301 successful water samples, of which 32 were replicate 
samples, and 165 calibration measurements were performed during the 
cruise. 


Table 4.3.1: Precision of tracer measurements determined from replicate 
             measurements and approximate limit of detection.  

                           Compound  Precision
                           ————————  —————————
                           SF6         1.8% 
                                     0.038 fM 
 
                           CFC-12      0.59%      
                                     0.0092 pM 
 

Figure 4.3.1: An example of a depth profile from the Western Basin. Note 
              that this is preliminary data.  



4.4.  Dissolved Oxygen  
      (PI Evin McGovern MI, Fran Aparicio NUI Galway) 
   

4.4.1  Methodology: 

Water samples were collected at all sampling events for measurement of 
dissolved oxygen using the modified Winkler method. Samples were 
collected and tested at all 58 stations sampled in the GOSHIP A02 2017 
section and dissolved oxygen concentration was determined in 1232 
samples.     
 
4.4.1.1  Sampling 
Water samples for dissolved oxygen (DO) testing were the first or second 
(after CFCs where CFCs were sampled) samples collected from Niskin 
bottles after it was returned to deck. Samples were taken following the 
GO-SHIP procedures described in Langdon (2010) and Dickson (1996). Water 
was collected in 100 mL pre-weighed glass flasks employing a Tygon tube 
to avoid bubble formation. Samples were immediately fixed by adding 1 mL 
of manganese chloride (MnCl)2)-4H2O 3M) and 1 mL of alkali-iodide 
solution (NaOH 8M + NaI 4M), then the stopper was inserted into the 
bottle and flasks were shaken vigorously. Temperature of the water at 
fixation was recorded in a separate glass bottle with a digital 
thermometer. The samples were allowed to sit and approximately 30 min 
later, samples were reagitated and the stoppered flask brims were filled 
with deionized water to ensure seal was maintained. Glass bottles were 
stored in darkness at room temperature typically for between 3-4 hours, 
before being analysed for dissolved oxygen. Two people performed the 
dissolved oxygen sampling to ensure rapid fixing once samples were 
collected from the Niskin bottles (Shift 1 Evin McGovern and Margot 
Cronin; shift 2 Fran Aparicio with Clynt Gregory, Liz Kerrigan or 
Vronique Merten). 
 
4.4.1.2  Analytical Method 
Dissolved oxygen concentrations in the water samples were quantified 
using the modified Winkler method as described by Langdon (2010). 
Analyses was carried out with two automatic 5 mL burettes "848 Titrino 
plus" (Metrohm, Switzerland) and amperometric end-point detection. To 
dissolve the precipitate, 1 mL of sulphuric acid (H2SO4 5M) was added to 
each sample and place on a magnetic stirrer. The sample was titrated with 
0.2M thiosulphate. 
 
Concentration of thiosulfate solution was periodically determined by 
standardization with potassium iodate solution (0.0023M). Reagent blanks 
were also measured periodically during the cruise. The final volume of 
dissolved oxygen contained in each sample was calculated with the 
equations presented in Langdon (2010).  
 
4.4.1.3  Volumetric Calibrations 
Stoppered flask volumes were gravimetrically determined before the survey 
and analytical volumes dispensed were also gravimetrically calibrated 
pre-survey. Laboratory temperature was recorded throughout the survey. 
   

4.4.2: QC: 

107 replicates were collected typically, two on each cast. The mean 
difference between the duplicate samples was 0.38% with little difference 
between the titrinos used; duplicates measured on titrino 1. 0.31% 
(n=27), titrino 2   0.46% (n = 19) and duplicates separately tested on 
each titrino 0.39% (n = 61). 
 

4.4.3: Problems encountered 

Overall, no major issues were encountered during the cruise. 
 

4.4.4: Preliminary Results 

The preliminary modified Winkler dissolved oxygen profiles for the 
section are shown in Figure 4.4.1 below (results subject to full QC check 
to be completed). Highest values were measured in the colder surface 
waters at the Canadian shelf edge. Surface waters (<30m) were generally 
close to 100% saturation (mean DO % Sat 105.1%, range 95.3 - 116.8.%, n 
=79).  
 
 
Figure 4.4.1: Dissolved oxygen (mol/kg) depth profiles as determined by 
              modified Winkler method (preliminary data not quality 
              checked). 
 
 
4.4.5  Comparison with SBE 43 DO sensor: 

An issue was identified with the SBE 43 sensor (SN 3339) for stations 
CE17007-01 to 03. The sensor was swapped out for station 4 and replaced 
with SBE 43 (SN 1416), Thereafter, the dissolved oxygen laboratory and 
sensor values correlated very well (r2 = 0.97 Figure 4.4.2) with the 
exception of station 27 where a problem with the CTD pump was noted. The 
Winkler measured DO concentrations were on average 12.4 µmol/kg higher 
than the SBE43.  Although the correlation was good, a plot of the 
residuals between the SBE43 and laboratory measured dissolved oxygen 
(figure 4.4.3) indicates a greater deviation between sensor and 
laboratory measured for deep water samples. High and low outlier Winkler 
concentrations at samples 100342 (st 21, 3698m) and 100439 (st 25, 2899m) 
not apparent in sensor profiles indicate likely sampling/titration error 
for these samples. 
   
 
Figure 4.4.2: Laboratory measured DO vs SBE 43 in situ DO (µmol/kg) for 
              all data excluding stations 1-3 and 27 (Preliminary data) 
              Inset zoom on central line 

Figure 4.4.3: Class scatter plot of dissolved oxygen residuals (Winkler 
              - SBE 43 µmol/kg) against Bedford number (i.e. sample 
              sequence over the course of the survey) shows depth 
              dependency of the residuals. Triangles show station 27 
              where there was a problem with CTD pump. Stations 1-3 are 
              omitted as there was an issue with the SBE 43 (subsequently 
              swapped out) 
 


4.4.6  References 

Langdon, C. 2010, Determination of Dissolved Oxygen in Seawater by Winkler 
    Titration Using the Amperometric Technique in The GO-SHIP Repeat 
    Hydrography Manual: A Collection of Expert Reports and Guidelines. 
    Hood, E.M., C.L. Sabine, and B.M. Sloyan, eds. IOCCP Report Number 
    14, ICPO Publication Series Number 134. Available online at: 
    http://www.go-ship.org/HydroMan.html. 
 
Dickson, A. D. 1996. Determination of dissolved oxygen in sea water by 
    Winkler titration. WOCE Operations Manual, Part 3.1.3 Operations & 
    Methods, WHP Office Report WHPO 91-1. 
  

 
4.5.  Nutrients (Nitrate, Nitrite, Phosphate and Silicate) 
      (Margot Cronin, Clynt Gregory, Claire Normandeau, Liz Kerrigan-
      shipboard, Doug Wallace-Land based, Triona McGrath-Land based (PI)) 


4.5.1.  Objectives:  

        1. To repeat the sampling plan of GO-SHIP 1997 

        2. To carry out on-board analysis of samples from all stations 
           and all depths  

        3. To carry out an on-board inter-comparison on similar nutrient 
           analyser systems used by Marine Institute and Dalhousie  
           University 


 
4.5.2.  Methodology:  

The Marine Institute and Dalhousie University teams both independently 
sampled and tested inorganic nutrients on-board. The Marine Institute was 
the primary nutrients team, with the Dalhousie team additionally sampling 
from selected stations. Both teams used a Skalar SAN++_ Continuous Flow 
Analyser for analysis. Sampling, sample preservation and analytical 
procedures on both systems followed methods outlined in the GO-SHIP 
guidelines for nutrient analysis at sea (Hydes et al., 2010), while both 
groups also incorporated their existing laboratory quality control (QC), 
which was specifically adapted to their individual instruments. Both 
teams operated similar sampling and analysis approaches with some minor 
differences. The Marine Institute methodological details are set out in 
Table 4.5.1. 

4.5.2.1.  Sampling Procedures  
Both groups collected nutrient samples directly from the Niskin bottles 
into falcon tubes and as per GO-SHIP guidelines, the samples were not 
filtered. Samples were analysed on board typically within 12 hours of 
sampling.   

Samples were taken in triplicate; "A" samples were analysed on board and 
replicates ("B" and "C" samples were frozen at -20°C. As per GO-SHIP 
guidelines, samples were not filtered. Concentrations of nutrients (PO4, 
NO3, NO2, Si(OH)4) were measured in 1277 samples from 58 stations. 

4.5.2.2. Analytical Methods 
Analysis was carried out by Skalar SAN++ Continuous Flow Analyser, setup 
in containerised laboratories on deck. The nutrient system runs four 
channels of nutrients simultaneously; total-oxidised nitrogen, nitrite, 
silicate and phosphate. The instrument consisted of an auto-sampler, 
where a needle draws the sample into the analyser which is then spilt 
into the four channels. Each channel has its own set of reagents, where 
the stream of reagents and samples is pumped through the manifold to 
undergo treatment such as mixing and heating before entering a flow cell 
to be detected. The air-segmented flow promotes mixing of the sample and 
prevents contamination between samples. The reagents act to develop a 
colour, which is measured as an absorbance through a flow cell at a given 
wavelength. The Skalar Interface transmits all the data to the Skalar 
Flow Access software. 

The reagents were made using high-purity chemicals, pre-weighed using a 
high-precision calibrated balance prior to the survey. They were stored 
in acid-washed polyethylene (PE) containers and mixed to final volume 
using Milli-Q water, see reagent compositions in Table 1. Reagent storage 
time was in accordance with the Skalar methods, most can be stored for 1 
week, the silicate ammonium heptamolybdate and oxalic acid reagents for 1 
month, however fresh reagents were typically made every 2-3 days due to 
volume required on the survey.  

 
Table 4.5.1: Details of sampling, instrument configurations (including 
             sample and reagent tubing sizes) and reagent compositions 
             for each nutrient from the Marine Institute, Ireland 

——————————————————————————————————————————————————————————————
SAMPLING 
  
Sample tubes               50ml falcon tubes 
 - Rinsed 3 times with 
   sample water before 
   filling. 
Primary sample analysis    Within 12 hours of sampling               
Replicate samples          Frozen immediately to -20°C               

ANALYSIS                              

Auto-sampler size          300 cups               
Auto-sampler cup size      10ml               
Baseline wash              Artificial Seawater               
Analysis Lab Temperature   20°C               

REAGENTS               
   (Chemicals g/L or ml/L)               

Artificial Seawater        35g Sodium Chloride               
                           0.5g Sodium hydrogen carbonate               

TOxN                              

Sample tubing size         1.02 ml/min               
Colour Reagent             150ml Phosphoric Acid               
                           10g Sulfanimide               
                           0.5g N-(1-Naphthyl)ethylene diamine 
                           dihydrochloride (NEDD)               
                              

   Reagent tubing size     0.42 ml/min               
Buffer Solution (pH 8.2)   80g Ammonium Chloride               
                           ~3ml Ammonia Solution                
                           3ml Brij solution (surfactant)               

   Reagent tubing size     0.8 ml/min               
Cadmium column             Skalar 5358 activated Cd column               
Copper Sulfate Solution                              
Nitrite                              
Sample tubing size         0.42 ml/min               
Colour Reagent             150ml Phosphoric Acid               
                           10g Sulfanilamide               
                           0.5g NEDD               
                              
   Reagent tubing size     0.23 ml/min               
Wash Solution              3ml Brij solution                
   Reagent tubing size     1.00 ml/min               
Silicate                              
Sample tubing size         1.40 ml/min               
Sulfuric Acid Solution     20ml Sulfuric Acid               
                              
Reagent tubing size        0.23 ml/min               
Ammonium heptamolybdate    20g Ammonium heptamolybdate               

   Reagent tubing size     0.42 ml/min               
Oxalic Acid                44g Oxalic Acid               
   Reagent tubing size     0.42 ml/min               
L(+) Ascorbic Acid         40g Ascorbic Acid               
   Reagent tubing size     0.32 ml/min               

   Phosphate                              
Sample tubing              1.40 ml/min               
Ammonium heptamolybdate    0.23g Potassium antimony (III) 
oxide tartrate             70ml Sulfuric Acid               
                           6g Ammonium heptamolybdate               
                           2ml FFD6 (Skalar Surfactant)               

   Reagent tubing size     0.42 ml/min               
L(+) Ascorbic Acid         11g Ascorbic Acid               
                           60ml Acetone               
                           2ml FFD6               

   Reagent tubing size     0.42 ml/min 
——————————————————————————————————————————————————————————————

 
Determination of nitrite: diazonium compound formed by diazotizing of 
sulfanilamide by nitrite in water under acidic conditions (due to 
phosphoric acid in the reagent) is coupled with N-(1-naphthyl) 
ethylenediamine dihydrochloride to produce a reddish-purple colour, which 
is measured at 540 nm. 
 
Determination of silicate: the sample is acidified with sulphuric acid 
and mixed with an ammonium heptamolybdate solution forming molybdosilicic 
acid. This acid is reduced with L(+)ascorbic acid to a blue dye, which is 
measured at 810 nm. Oxalic acid is added to avoid phosphate interference. 
 
Determination of phosphate: ammonium heptamolybdate and potassium 
antimony(III) oxide tartrate react in an acidic medium (with sulphuric 
acid) with diluted solutions of phosphate to form an antimony-phospho-
molybdate complex. This complex is reduced to an intensely blue-coloured 
complex by L(+)ascorbic acid and is measured at 880 nm. 
 
Determination of total oxidised nitrogen (TOxN): sample is buffered to pH 
8.2, and passed through a column containing granulated copper-cadmium to 
reduce nitrate to nitrite. The nitrite (originally present plus reduced 
nitrate) is determined by diazotizing with sulfanilamide and coupling 
with N-(1-naphthyl) ethylenediamine dihydrochloride to produce a reddish-
purple colour, which is measured at 540 nm.  
 
The instrument was calibrated daily using a suite of calibration 
standards (see calibration range in Table 4.5.2). The primary standard 
for each nutrient was made up in the MI laboratory on shore just before 
the survey using a calibrated balance where the dry weight of each high 
purity chemical was diluted to 1L with Milli-Q water, as per Skalar 
methods. The primary stocks were stored in the fridge for the duration of 
the survey. Two batches of primary stocks were used to ensure no bias 
from an individual batch. Weekly secondary stocks were made from the 
primary stocks into 100ml PP flasks, which were stored in the fridge when 
not in use and could be used for one week. Daily standards were made from 
secondary stock into 100ml PP volumetric flasks.  


Table 4.5.2: Concentrations of daily calibration standards in µmol/l. 
             Standard 1 is the blank made of artificial seawater (sal 
             35). SSS are the System Suitability Standards that were 
             analysed during a run as internal quality standards. 


                STD    TOxN   Silicate   PO4     NO2    
                 #    µmol/l   µmol/l   µmol/l  µmol/l
               —————  ——————  ————————  ——————  ——————
                 1      0        0       0       0
                 2      0.26     0.26    0.05    0.05
                 3      0.5      0.5     0.15    0.15
                 4      2.5      2.5     0.25    0.25
                 5      5        5       0.5     0.5
                 6     10       10       1       1
                 7     15       15       1.5     1.5
                 8     22.5     22.5     2.25    2.25
                 9     30       30           
                10     40       40           
                11     50       50           
                12              60           
                SSS    10       10       1       1
               Drift   10       10       1       1


Secondary and daily calibration standards were made using calibrated 
fixed volume pipettes. The adjustable pipettes were tested prior to the 
start of the survey to ensure that the volumes delivered were accurate. 
The secondary stocks were made using Milli-Q water, while the daily 
standards were made using artificial seawater (ASW) with salinity of 35. 
Concentrations of daily standards for each system are in Table 2, where 
first order calibration was used and R2 > 0.99 was deemed acceptable, as 
per Skalar methods. 

ASW was used as the baseline wash for all channels, at a similar salinity 
to the expected samples (salinity 35). Batches of sodium chloride used 
were tested prior to the survey to ensure no contamination with any of 
the nutrients. Calibration was not forced through zero, and baseline wash 
was run as the first standard. 

4.5.2.3.  Quality Control 
The Certified Reference Materials (CRMs) used on the survey were supplied 
from KANSO (Aoyama et al., 2016; Aoyama et al., 2007) and were analysed 
at the beginning and end of every run and monitored daily on quality 
control charts. Two batches were used (Batch CD and Batch BW) to cover 
the full range of nutrients expected on the survey, a CD and BW were 
analysed at the beginning of a run and another CD at the end of the run.  

The silicate BW CRM (61.47 µmol/l) is higher than highest standard (60 
µmol/l) used by both groups and is therefore only used as indicative QC 
for high levels of silicate. 

 
4.5.3.  Problems encountered. 

Persistent but untraced nitrite contamination resulted in CRM failures 
throughout the survey. 

Ships vibrations were a particular problem for the MI containerised 
laboratory at its location on deck (not previously encountered including 
on transit leg). Communication problems between the interface and the 
laptop were encountered initially due to a faulty UPS. Later 
communication problems were considered to be a result of vibration from 
the engine at higher revs or a build-up of nutrient data files in the 
flow access working folder. This did not compromise data quality since 
analysis ceased when there was a communication issue.  

The above issues may have contributed to higher variability for TOxN and 
silicate was evident for the MI testing compared with routine shore-based 
method performance. 


4.5.4. Interim results 

Interim summary results are shown below. Some minor data corrections will 
be expected following comprehensive QC checks. 


Figure 4.5.1: Vertical distribution of (a) TOxN, (b) SiO4 and (c) PO4 
              observed during CE17007 (preliminary shipboard data).  
 

4.5.5.  Inter-comparison 

A comprehensive analysis of the results of the inter-comparison has not 
been carried out. A brief initial comparison of results from 12 stations 
showed a good comparison in silicate and phosphate profiles (despite 
noise in phosphate data from the Dalhousie system), and while initially 
there appeared to be an offset TOxN data where the MI TOxN was lower in 
the deeper stations - after including the higher TOxN standards in the MI 
calibration (matching that of Canada), the results were comparable.  The 
calibration standard concentrations for the MI system are given below 
Table 5.3.1a, while the calibration standards for the Dalhousie system 
are given in Table 5.3.1b. The MI uses an artificial seawater baseline 
matrix, while the Dalhousie system uses deionised water.  
 
Samples from profiles of twelve stations were carried out by the team 
from Dalhousie University, Halifax (Dal) using similar but not identical 
methodology and a Skalar SAN++ CFA system, 
 
 
Table 4.5.3: Calibration standard concentrations (µM/l) for (a) the MI 
             Skalar system and (b) the Dalhousie Skalar system. 

          TOxN    NO2   SiO4   PO4         TOxN  NO2  SiO4  PO4
          —————  —————  —————  ————        ————  ———  ————  ———
           0      0      0     0             0    0     0    0
           0.26   0.05   0.26  0.05         10    1    10    1
           0.5    0.15   0.5   0.15         20    2    20    2
           2.5    0.25   2.5   0.25         30    3    30    3
           5      0.5    5     0.5          40    4    40    4
          10      1     10     1            50    5    50    5
          15      1.5   15     1.5          60    
          22.5    2.25  22.5   2.25          
          30      30              
          40      40              
          50      50              
                  60            
          —————————————————————————        ————————————————————
                      a                             b
  
Slight differences between the two systems included  
    • Differences in some reagents 
    • Differences in some tubing sizes  
    • Differences in initial concentrations of some standards (Table   
      4.5.3). 
    • The MI uses an artificial seawater baseline matrix, while the  
      Dalhousie system uses deionised water.  


 
A comprehensive analysis of the results of the inter-comparison has not 
yet been completed. A brief preliminary comparison of results showed a 
good comparison in silicate and phosphate profiles, and while initially 
there appeared to be an offset in TOxN data where the MI TOxN was lower 
in the deeper stations - after including the higher TOxN standards in the 
MI calibration (matching that of Canada), the results were comparable.   
 
It is intended to work up and publish the details and results of the 
inter-comparison.  
 
 
 
4.6.  Carbon System Parameters 
      (Ellie Morris, Richard Sims, Lachlan Riehl and Riccardo Arruda-
      shipboard participants; Ute Schuster - Principal Investigator)  


The carbon parameter analytical equipment was set up pre-cruise in a 
seagoing laboratory container belonging to the University of Exeter, 
Devon, UK. Discrete CTD samples were analysed for total inorganic carbon 
(DIC) and total alkalinity (TA).  


4.6.1.  Sampling and Preparation for Analysis 

Dissolved Inorganic Carbon (DIC) and Total Alkalinity (TA) measurements 
were performed on seawater samples collected from 10L Niskin bottles 
deployed on a 24 Niskin CTD rosette. 500ml glass bottles were used to 
sample the Niskin bottles triggered at the greatest and shallowest depths 
of each stations, in addition to two depths chosen at random, allowing 
for in bottle replicate measurements to be made. These are used during 
analysis to indicate the precision of the measurements made by the VINDTA 
machine at each station. All remaining Niskin bottles were sampled using 
250ml glass bottles. Following Standard Operating Procedure (SOP) #01 
(Dickson et al., 2007) the glass bottles were rinsed from the Niskin 
twice and then a Tygon sampling tube was inserted into the bottle, which 
was allowed to fill and then overflow for the same amount of time it took 
the bottle to fill. A glass stopper was then placed into the bottle and 
immediately after the samples were collected they were 'fixed' to prevent 
the growth of any organic matter. The samples were fixed by removing 
250.L of seawater from each 250mL sample and adding 50.L of saturated 
mercuric chloride. Quantities were doubled for the 500mL samples. Once 
poisoned, samples were stored in foam-lined crates in the wet laboratory 
of the ship until analysis, at which point they were acclimatized to the 
25°C air temperature of the laboratory container prior to resting in a 
25°C water bath. 

Due to inclement weather, the 24 Niskin CTD rosette could not be deployed 
at stations 15, 16, 17, 18 and 19 and thus no samples could be analysed.  
Stations 30, 32, 34, 36 and 38 were also missed in order to make up for 
lost time associated with weather and malfunctions with the CTD tether.   


4.6.2.  Dissolved Inorganic Carbon Analysis 

All measurements were completed on two Versatile INstrument for the 
Determination of Titration Alkalinity (VINDTA, version 3C, SN#064 and 
#065, Marianda, Germany, Mintrop, 2004) each connected to a coulometer 
(SN135015020 and SN135015019 respectively). Water samples were first 
analysed for Dissolved Inorganic Carbon (DIC). An excess of phosphoric 
acid (1M, 8.5%) was added to a calibrated volume of seawater sample to 
convert all inorganic dissolved carbon to CO2. This CO2 was then 
transported to the coulometer cell by Oxygen-free-Nitrogen gas (OfN), 
which was filtered through soda lime to remove any residual traces of CO2 
prior to coming in contact with the recently converted CO2. In the cell, 
all CO2 is quantitatively absorbed to form an acid that is subsequently 
titrated via coulometry. See Dickson et al., (2007) SOP #02 for more 
detailed information.  

The DIC pipette is surrounded by a water jacket to maintain the same 
temperature as the samples (25°C). Coulometer counts were calibrated 
against replicate analyses taken from the 500mL bottles and Certified 
Reference Material (CRM batch 163, certified at 2039.49 ± 0.73 for DIC 
(Prof A Dickson, Scripps Institution of Oceanography, San Diego, USA)), 
which were run immediately before and after the coulometer cell was 
changed, in addition to 

halfway between the first and last CRMs run on each cell. The coulometer 
cell was replaced every 24 hours with the cell and both lid IDs recorded 
for comparison purposes. The coulometer cells, anode and cathode solution 
used were purchased from Cobalt Scientific (Cobalt Scientific, 
Bensenville, Illinois, United States).  

Initial DIC calibration was done during the cruise for each instrument by 
correcting all sample data by the difference between the mean of all 
CRMs. Post-cruise data quality control will include the calibration of 
the DIC readings for each coulometer cell used during CE17007, 
identification and removal of errors/outliers and accounting for 
instrument drift.  


4.6.3.  Titration Alkalinity Analysis 

Total Alkalinity was measured by potentiometric titration using the same 
VINDTA machines as for DIC analysis. These systems use a highly precise 
Metrohm Titrino for acid addition, an ORION-Ross pH electrode, a Metrohm 
reference electrode and an auxiliary electrode. Similarly, to the DIC 
analysis, the pipette and analysis cell were kept at the same temperature 
as the samples (25°C) by a water jacket. Hydrochloric acid (0.1M) made to 
the ionic strength of seawater was used as the alkalinity titrant as 
described in SOP#3B (Dickson et al., 2007). Alkalinity values were 
calibrated using replicate analyses taken from the 500mL bottles and CRM 
batch 163 (certified at 2215.53 kg-1 ± 0.56 for TA). See Dickson et al., 
(2007) SOP #03 for more detailed information.  Post-cruise data 
corrections will include a recalculation of alkalinities using CTD 
temperature, salinity and nutrients, and also incorporate a recalibration 
of the alkalinity pipettes' volume and temperature sensors. Post-cruise 
Quality Control will identify and remove outliers and account for drift 
in the instruments' alkalinity measurements taken over the course of the 
cruise. 


4.6.4.  Sample Analysis Strategy and Ship-board Instrument Maintenance.  

VINDTA #064 was connected to coulometer SN:135015020 and Metrohm Titrino 
SN:01270505. DIC pipette volume was 17.62ml* and alkalinity pipette 
volume was 105.00ml as calibrated following SOP#12 (Dickson et al., 
2007). On 4th May Metrohm electrode SN00562703 was swapped for new 
electrode SN00753480 as the glass tip was getting stuck regularly. On May 
4th, analysis was changed from dual to single sample analysis, due to an 
irregularity between the two sample lines resulting in less precision 
between duplicates. From this point on, samples were analysed using only 
one sampling line, line 1.  

VINDTA #065 was connected to coulometer SN:135015019 and Metrohm Titrino 
SN:17850010. DIC pipette volume was 111.05ml and alkalinity pipette 
volume was 17.96ml, as calibrated following SOP#12 (Dickson et al., 
2007). The touch screen of coulometer SN:135015019 attached to VINDTA 
#065 was cracked on May 14th 2017 while analysing samples from station 
31. It was kept functioning until the cell change on May 19th 2017 at 
approximately 03:00hrs, midway through station 52, after which the touch 
screen was no longer responsive and the cell could not be changed. With 
no spare coulometers or alternative control mechanisms to run the damaged 
coulometer, we were forced to shut down the VINDTA #064 machine on May 
19th at approximately 11:00 hrs. Limited time remaining on the vessel and 
only one machine remaining for analysis resulted in an adjusted sample 
analysis pattern for the remaining stations, as outlined below: 

    - Stations 1 - 52: All depths (24 per station) sampled and analysed.  
    - Stations 51, 53, 55, 57, 59, 61: 18 samples analysed per station to 
      match depths taken by Chlorofluorocarbons (CFCs) and 13C. 6 
      remaining unanalysed samples stored and taken for analysis in 
      laboratory at University of Exeter. 
    - Stations 52, 54, 56, 58, 60, 62, 64: sampled, fixed and stored for 
      analysis in lab at University of Exeter. 
    - Station 63, 65 and 67: all depths sampled and analysed (shallow 
      stations).  



REFERENCES 

Dickson, A. G., Sabine, C. L., and Christian, J. R. (Eds.) (2007), Guide 
    to best practices for ocean CO2 measurements, PICES Special 
    Publication 3, pp.191 

Johnson, K. M., King, A. E., and Sieburth, J. M (1985), Coulometric TCO2 
    analyses for marine studies; an introduction, Marine Chemistry, 16, 
    pp. 61-82 

Johnson, K. M., Sieburth, J. M., Williams, P. J. l., and Braendstroem, L. 
    (1987), Coulometric total carbon dioxide analysis for marine studies: 
    automation and calibration, Marine Chemistry, 21, pp. 117-133 

Johnson, K. M., and Wallace, D. W. R. (1992), The Single-Operator 
    Multiparameter Metabolic Analyzer for total carbon dioxide with 
    coulometric detection, DOE Res. Summary, 19, pp. 1-4 

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, Marine Chemistry, 44, pp. 167-187 
  


4.7.  δ13C Dissolved Inorganic Carbon (DIC) 
      (Lin Cheng, Claire Normadeau) 


The Canadian team oversaw analysing the stable isotopes of carbon (δ13C) 
on dissolved inorganic carbon (DIC) during this GO-SHIP scientific 
survey. To our knowledge, this is the first time that this measurement is 
being conducted at sea. Normally, the samples are collected and brought 
back to the laboratory for measurements on an isotope ratio mass 
spectrometer (IRMS). This time, an Apollo DIC analyzer coupled to a 
carbon dioxide Picarro cavity ring down spectrometer (CRDS) were taken on 
board the vessel, providing a more compact instrumentation that can be 
utilized at sea even in rough conditions.  Overall the system behaved 
well and we were able to collect valuable data. The main objective of 
this project was to evaluate the system’s precision and accuracy and to 
test this new instrument at sea.  


4.7.1.  Sampling 

Samples were collected in 160 ml serum glass bottles and crimped with 
flat butyl/Teflon septa and aluminum seals. Media borosilicate glass 
bottles (250 ml) with plastic screw caps were also used. An 
isoversinic/viton tubing was connected to the Niskin bottles and the 
sample bottles were rinsed three times with the seawater samples.  The 
bottles were filled gently from the bottom using the tube which extended 
from the Niskin drain to the bottom of the glass sample bottle. The 
bottles were overflowed by at least half their volume and they were 
crimped or screwed capped right away. After all samples were collected, 
they were brought back to the container where they were poisoned with 100 
ul of saturated mercury chloride solution (250ul of HgCl2 for the 250 ml 
bottles). To account for water expansion as samples warm up, 1.6 ml of 
water sample was taken out using a needle and syringe before adding the 
mercury chloride. A needle and syringe filled with sodium hydroxide on 
support was inserted through the septa while removing the water to 
prevent CO2 from entering the sample bottle. For the 250 ml screw cap 
bottles, they were simply opened, 2.5 ml sample was removed, mercury 
chloride was added and the bottle were re-capped. Samples were kept at 
least 30 min in a water bath set at 21°C before analysis. 

Due to a rather long analysis time (30 min), only the odd station numbers 
were sampled (except for a few even station numbers at the beginning of 
the survey) and 14 depths were sampled per cast. Duplicate samples were 
taken at one depth on most casts.  


4.7.2. Instrumentation 

The analyses were conducted on an Apollo SciTech DIC-δ13C Analyzer 
(model AS-D1) connected to a Picarro G2201i cavity ring down spectrometer 
for stable isotopes of carbon dioxide and methane. The Apollo analyzer 
consists of an acidification chamber cooled at 4°C, where 1 ml of 5% 
phosphoric acid is added to 3.8 ml of sample. The sample is then purged 
for approximately 10 min and the carbon dioxide is sent to the Picarro 
analyzer via an ultra-pure compressed air carrier gas flow of 60 ml.min-
1. For measurement with the serum and septa bottles, one needle connected 
to the Apollo analyzer with tygon tubing was inserted through the septum 
of the sample bottle.  A carbon trap made of sodium hydroxide on support 
in a plastic syringe was also poked through the septum to prevent any CO2 
from entering the bottle during the analysis. For measurement with screw 
cap bottles, the cap was removed and replaced with a similar cap in which 
an opening had been made for the sample tubing. Multiple measurements 
were made per sample bottle until a standard deviation of at least 0.12 
was reached on dissolved inorganic carbon concentration.  


4.7.3.  Preparation of standards and phosphoric acid 

The 5% phosphoric reagent acid was diluted from 85% o-phosphoric acid. 
Pre-combusted sodium chloride was added into the acid to obtain a 10% 
NaCl solution. This solution was dispensed in many 250 ml serum bottles, 
purged by ultra-pure helium gas for 30 mins, and then crimped.  

All standards were prepared in 160 ml serum bottles. Three sets of 
standards for DIC concentration (1.8mM, 2.1mM, 2.4mM) were made by 
dissolving different quantities of pre-combusted sodium bicarbonate 
powder into helium purged MilliQ water.  Three sets of δ13C-DIC standards 
were made by dissolving sodium carbonate and sodium bicarbonate powder 
with different δ13C values (pre-determined by an Elementar EA-IRMS) into 
pre-purged MiliQ water.  


4.7.4. Quality control 

Once a week, one calibration curve for δ13C and DIC concentration were 
done and every day one CRM (batch 157) and one δ13C standard was measured 
to check the stability of the measurements. Preliminary results show 
precisions of 0.06 permil on δ13C and 6 µmol.kg-1 on all CRMs run on the 
survey.  Replicate injections of seawater samples had an average 
precision of 0.03 permil for δ13C and an average standard deviation of 
1.4 uM.kg-1 on DIC. 

Deep water samples from the West European Basin were taken and will be 
compared to previous studies providing cross-over analysis of the data. 

The opportunity was taken to collect multiple samples from one same 
Niskin bottle at station 58 and 60 in the very deep waters located in the 
West European Basin. These samples will be used in an intercomparison 
round-robin activity that will hopefully take place in 2017. It will be a 
unique opportunity to have different laboratories measure and compare 
results on dissolved inorganic carbon concentrations as well as δ13C.  


4.7.5. Problems 

The gas carrier air flow was set at 60 ml.min-1 but had to be increased 
to 80 ml.min-1 half-way throughout the survey. For unknown reasons, the 
DIC peak shape changed and the desired precision could not be attained 
while using a 60 ml.min-1 flow.  All flows and valves were checked and 
were behaving perfectly, no leak was detected, so the source of the peak 
change was unknown. To be able to continue analysing samples, it was 
decided to increase the carrier flow to 80 ml.min-1.  This improved peak 
shape and the desired precision was reached. 

  



5.  PRELIMINARY RESULTS - UNDERWAY MEASUREMENTS 


5.1.  Meteorological Data 

Data from the shipboard system on the Celtic Explorer includes 
observations and measurements of meteorological (e.g. air temperature, 
atmospheric pressure, relative humidity, wind speed and direction) at 10m 
above sea level at a per minute rate. This data is available from the 
Marine Institute.  



5.2.  Thermosalinograph Data 

Data from the shipboard system on the Celtic Explorer includes 
observations and measurements of oceanographic parameters (e.g. sea 
surface temperature/salinity) at approximately 3m below the surface. This 
data is available from the Marine Institute. 



5.3.  Shipboard ADCP 
      (Postprocessing of data: Christian Mohn)  
      (Shipboard ADCP group: Caroline Cusack, Peter Croot and Marshall 
      Swartz) 


5.3.1.  Introduction 

Underway current and backscatter measurements were performed continuously 
along the cruise track using the ship’s Acoustic Doppler Current Profiler 
(SADCP). The system used was a 75 kHz RDI Ocean Surveyor (OS75) mounted 
in the ship’s hull. RDI’s VMDas software was employed for SADCP setup and 
data collection. The overall recording period was from the 28-April-2017 
(20:48) to 21-May-2017. The SADCP was run in broadband (BB) mode. The 
built-in transducer misalignment angle relative to the ship’s keel was 45. 
The number of depth bins was set to 60 with a bin size of 16 meters and a 
blanking distance of 8 meters. The transducer depth was 9 meters. Single 
ping bottom tracking was enabled during the whole cruise. 


5.3.2.  Data Processing 

Before data processing, single ping ENX velocity profiles were time-
averaged to 5 min ensembles for reducing data noise, but retaining a 
sufficient horizontal along-track resolution. ENX files are single-ping 
data including navigation and are transformed into Earth coordinates and 
screened for error velocity and false targets. The Common Oceanographic 
Data Access System (CODAS) was used for data processing. CODAS is an 
SADCP data post-processing toolbox from the University of Hawaii (Firing 
et al. 1995; http://currents.soest.hawaii.edu/docs/adcp_doc/index.html). 
Post-processing was conducted following Go-ship recommendations (Firing 
and Hummon 2010). Water track calibration was conducted to obtain best 
estimates for the transducer amplitude scale factor and transducer 
orientation relative to the ship's heading. Bins 5-20 (93-333 m depth 
range) were taken as the oceanic reference layer, thus avoiding short-
term variability caused by ship-induced turbulence and weather events. 
The correction factors for transducer orientation (phase angle) and 
amplitude from the water track calibration were 6.76 and 1.007, 
respectively. An additional bottom track calibration was conducted and 
largely confirmed the water track calibration values (phase angle 6.78, 
amplitude 1.035). The next processing step included quality control of 
individual ensemble profiles and bins. The aim was to retain velocity 
profiles/bins not affected by ship-induced turbulence, object 
interference and bottom reflection. Finally, the navigation calculation 
of the ship's position and speed was carried out to obtain best estimates 
for ship velocity and to calculate absolute current velocities.  


5.3.3.  Data set and results 

The final dataset includes 5-minute ensemble averaged profiles of the 3D 
variables u (East-West velocity component in m/s), v (North-South 
velocity component in m/s, raw echo amplitude (raw counts) and percent 
good value (quality indicator in percent). Figure 1 shows the fully 
processed variables u (m/s), v (m/s) and echo amplitude (raw counts). 
Figure 2 (upper panel) shows vector plots of CE17007 measured SACDP 
currents in 56 m water depth (first available depth level). Only every 
4th vector is shown. Velocity vectors are shown in light gray. The 
superimposed coloured contour plot shows the geostrophic surface current 
speed (in m/s) from the AVISO satellite altimetry (0.25 degree spatial 
resolution). Daily AVISO data were extracted for the cruise period (end 
of April to end of May 2017) and the time-average is presented here. The 
lower panel shows the AVISO geostrophic currents (m/s) as a vector plot. 
The blue line indicates the SADCP cruise track. There is reasonable 
agreement between satellite data and SADCP data in most areas. 

 
Figure 5.3.1: Velocity components u (upper panel), v (middle panel) and 
              echo amplitude (raw counts) vs water depth (m) plotted 
              along the cruise track. White areas indicated data gaps.  

Figure 5.3.2: Upper panel: Vector plot of SADCP currents in 56 m water 
              depth. Only every 4th vector is shown. Coloured contours 
              show geostrophic surface current speed (in m/s) from the 
              AVISO satellite altimetry (0.25 degree spatial resolution). 
              Lower panel: Vector plot of AVISO geostrophic currents 
              (blue line indicates SADCP cruise track). 




REFERENCES 


Firing E, Ranada J, Caldwell S (1995) Processing ADCP data with the CODAS 
    Software System, Version 3.1. University of Hawaii, Honolulu, HI, 
    USA. 

Firing, E., and J.M. Hummon (2010), Ship-mounted acoustic Doppler 
    current profilers, in The GO-SHIP Repeat Hydrography Manual: A 
    Collection of Expert Reports and Guidelines, ICPO Publication Series 
    Number 134, edited by E.M. Hood, C.L. Sabine, and B.M. Sloyan, 
    International CLIVAR Project Office (ICPO), Southampton, U.K. 
    (Available online at http://www.go-ship.org/Manual/Firing_SADCP.pdf.) 

 

5.4.  Underway pCO2 measurements (GO-8050) 
      (Margot Cronin, Anthony English) 


5.4.1.  Objectives 

    1. To carry out underway analysis of pCO2 in surface (-6 m) seawater 
       samples. 
    2. To carry out an on-board inter-comparison on different systems 
       used by Marine Institute and Dalhousie University (see report from 
       Ricardo Arruda) 


5.4.2.  Methodology 

5.4.2.1.  Equipment 

Underway measurements were carried out using a General Oceanics GO-8050 
Automated Flowing pCO2 measuring system (SN L12/21804/185). The pCO2 
system consists of a wet box (containing a shower-head equilibrator, 
pumps, chiller unit); a dry box, containing a LI-COR non-dispersive 
infrared (IR) analyzer (LI-7000 SN IRF4-1263) though which the 
equilibrator headspace is circulated for measurement of xCO2 and xH2O and 
a deck box (barometer and air intake).  

Water intake was from a depth of 6m at the bow, a distance of 
approximately 45m from the instrument. Measurements of temperature and 
salinity at the intake were made by Seabird SBE 21, SN 3314 (to 4 May) 
and SN 3315 (4 May onwards). 

Meteorological information was provided by Batos station. Air intake was 
positioned approximately 15m above sea level on a mast on the foredeck.  

GPS information was supplied by the ship’s GPS system. 

5.4.2.2.  Instrument configuration 

Table 5.4.1: GO-8050 configuration for A02 survey (according to 
             manufacturer’s recommendation). 

                The GO-8050 was configured according to 
               manufacturer’s recommendations in (below): 
             —————————————————————————————————————————————
             Parameter              Range
             —————————————————————  ——————————————————————
             H2O flow               2.7 - 3.0 l/min

             LICOR flow             ATM  80 - 100 ml/min
                                    EQU 70 - 100 ml/min
                                    STD ~60ml/min

             CO2 (µmol)             ATM  300-450 mol/min
                                    EQU 300 - 450 mol/min
                                    STD within 1% of value

             Vent flow              +/- 15ml/l
             H2O (mmol/m)           <4 mmol/m
             EQU pump speed         ~ 85
             Condenser temperature  5°C
             ATM & EQU cond         H2O > 9        

 

5.4.2.3.  System Overview (from General Oceanics manual) 

Seawater is circulated through a closed chamber (the main equilibrator) 
at a flow rate of about 2 L/min and a pressure around 4 psi. The water 
enters the equilibrator via a spiral nozzle, creating a conical spray, 
which enhances the CO2 gas exchanges between the water and the overlying 
air (headspace) in the equilibrator. The water is then gravity drained 
out of the system. An "inverted cup" system with a siphon break in the 
middle of the equilibrator effectively isolates the headspace gas from 
the outside air and greatly minimizes any gas loss due to air entrainment 
from the water flow. A smaller secondary equilibrator, where seawater 
flows at about 0.5 L/min and which is opened to the ambient air, is the 
replacement source for the minimal air loss that might still occur in the 
main equilibrator.  

The headspace gas is circulated through the system and back to the 
equilibrator with a pump (headspace pump) at about 100 mL/min. It is 
first dried by going through a Peltier cooling block (the Condenser) 
operating at about 5°C, then a Permapure Nafion tube. The dry gas is then 
sent to the Infrared LICOR analyzer (the LICOR) where its CO2 and H2O 
mole fractions (xCO2 and xH2O) are measured. 

Atmospheric air is also being measured alternatively by the system. A 
dedicated pump (ATM pump) constantly draws outside air, a portion of 
which is dried in a second channel of the condenser and flushes the 
content of a small reservoir (the ballast), a short length of PVC pipe 
open to the ambient air. The dry ballast atmospheric air is circulated 
through the LICOR for analysis. In addition, the ballast air is also used 
for the countercurrent flow in the outer chamber of the Permapure Nafion 
dryers and is pulled by a dedicated pump (the vacuum pump). 

An 8-port 16-position VALCO multiposition valve (the VALCO valve) selects 
the gas being circulated through the LICOR. A set of CO2 gas standards 
(supplied by the user) is measured regularly during normal operations in 
order to calibrate and correct for any drift of the LICOR. 

5.4.2.4.  Samples: 

Table 5.4.2: GO-8050 run sequence for A02 survey 
             Seawater samples from the ship’s underway (non-toxic) system 
             were passed through the shower-head equilibrator and 
             analysed by LICOR 7000 NDIR approximately every 2.5 minutes. 

                       Run sequence was as follow: 
                      —————————————————————————————
                      Step  Type    No. repetitions
                      ————  ——————  ———————————————
                        0   zero           1
                        1   span           1
                        2   STD1           1
                        3   STD4           1
                        4   STD2           1
                        5   STD3           1
                        6   ATM            5
                        7   EQU           50
                        8   LOOP2          4
                        9   FILTER         1
                       10   STD1           1
                       11   STD4           1
                       12   STD2           1
                       13   STD3           1
                       14   END            1       



5.4.2.5.  Calibration Standards 

Calibration standards were analysed for calibration at Mace Head 
Atmospheric Station using CRDS, Picarro G2301. Results as follows in 
Table 5.4.1. 

      
Table 5.4.3: Calibration results from CO2 standards. 
———————————————————————————————————————————————————————————————————————————————
CO2 (nominal)            200ppm        400ppm        600ppm        405ppm 
                                                                 (408.83ppm 
                                                                  certified)

CO2 (WMO-X2007)         198.29 ±      399.28 ±      606.52 ±       408.77 ±
                          0.01          0.01          0.01           0.01 

CH4 (WMO-W2004A)         15.53 ±       25.29 ±       16.07 ±      1920.09 ±
                          0.02          0.09          0.09           0.04
                            
port #                     10            11            12             9

Analysis period        170216 1200   170216 1200   170217 1200   170217 1200  
                        to 170217     to 170217     to 170217      to 170217

Air Products serial #    002047        089492        1108543         

Luxfer serial #          2911A         DL1231        D048791       CB12076

Air Products PR code     349640        324946        349639         

Type/Manufacturer       Al Luxfer     Al Luxfer     Al Luxfer    N150 Al Lufxer
Size                       50L           50L           50L           29.5L

Valve                   BS3 brass     BS3 brass     BS3 brass     CGA590 brass

Fill date              09 Jan 2017   27 Dec 2016   09 Jan 2017    January 2017

Location                Worcester,     Keumiee,     Worcester,       
                            UK         Belgium         UK   
———————————————————————————————————————————————————————————————————————————————


5.4.3.  QA       

Standards were run approximately eight times per day. Summary statistics 
are listed below.


Table 5.4.4: Summary statistics for calibration standards during A02 
             survey.

                             Mean       Median
           Actual value    measured    measured    SD     No. of 
              (ppm)       value (uM)  value (uM)        measurements
         ———————————————  ——————————  ——————————  ————  ————————————
   Std1    0.00              -0.34      -0.12     0.58      176 
   Std2  198.29 +/- 0.01    199.38     199.58     0.78      172
   Std3  399.28 +/- 0.01    398.83     399.17     0.97      172
   Std4  606.52 +/- 0.01    606.04     606.41     1.11      174



5.4.4.  Problems Encountered 

1. On the transit journey to St John’s, cold Labrador seawater (-0.7°C) 
   and cold air (0°C) caused the chiller in the instrument to freeze, 
   leading to damage of the fan. The instrument was shut down to allow 
   installation of a replacement chiller, and not restarted again until 
   beyond the colder Labrador waters on route to the survey line. 

2. An intermittent electrical fault in a plug board caused sporadic 
   shutdown over a period of several days leading to data gaps. Removal 
   of the surge protector in the plug board resolved the fault. 

3. The data feed from the SBE 21 crashed on four occasions. It was not 
   possible to recover the data for some of the down time. 

4. The FTP file upload process interrupted the writing of data on at 
   least three occasions, leading to some data gaps. 



5.4.5.  Interim results 

xCO2 results were pressure corrected and then temperature corrected 
(according to the formula derived by Takahashi et al, 1993 cited by 
Pierrot et al, 2009). Figure 5.4.1 below shows the pressure and sea 
surface temperature corrected pCO2 sampled by date from the beginning of 
the survey. 
 
Interim results for the cruise track are illustrated below. Following 
data reduction, the data from this instrument will be submitted to SOCAT.   
 
  
Figure 5.4.1: Preliminary (raw) surface pCO2 (µmol/mol) measured on A02 
              line, corrected for LICOR pressure and sea surface 
              temperature. 
 


References: 
 
Pierrot, D., Neill, C., Sullivan, K., Castle, R., Wanninkhof, R., Lüger, 
    H., Johannessen, T., Olsen, A., Feely R.A., Cosca, C.E., 2008. 
    Recommendations for Autonomous Underway pCO2 Measuring Systems and 
    Data Reduction Routines. Deep-Sea Research Part II. 
 
General Oceanics (2016) Instruction Manual, Model 8050, Automated Flowing 
    pCO2 Measuring System.xCO2 results were pressure corrected and then 
    temperature corrected (according to the formula derived by Takahashi 
    et al, 1993 cited by Pierrot et al, 2009). Figure 1 below shows the 
    corrected pCO2 SST sampled by date from the beginning of the survey. 
 
 
  

5.5.  Report of underway data (GO-SHIP Celtic Explorer - 2nd Leg) 
      (Ricardo Monteiro da Silva) 
 

5.5.1.  Underway systems 
 
In this Report of underway surface data in the Celtic Explorer we compare 
3 underway systems (4 pCO2 sensors). The systems are: SubCtech with 
sensors for pCO2, temperature and salinity; VOS (Aanderaa) with sensors 
for pCO2 (Prooceanus), CO2 optode, O2 optode, temperature, conductivity 
and Chlorophyll; And General Oceanics (GO) with sensors for pCO2 (air and 
water), temperature and salinity. 
 


5.5.2.  Temperature sensors 
 
    
Table 5.5.1: Underway temperature sensors 
 
Location            Model     Serial n
——————————————————  ————————  —————————————————————————————————
Intake              SBE38     Part n 90299.5, s/n: 3848425-0375
Before GO           SBE21     Part n 90399, s/n: 2148425-3315
SubCTech (outside)  SBE38     38.1110, s/n: 38-0799
SubCTech (inside)   SBE45     Part n ° 45.1, s/n: 45-0459
VOS                 Aanderaa  ??     

 
 
5.5.3.  Reference Gases 
 
SubCtech 

• Calibration with reference gases twice a day. 
• (1) Praxair - 531 ppm 
• (2) Praxair - 653 ppm 
• Cross-referenced with NOAA - 447.38 ppm  


 
General Oceanics 

• Nitrogen Zero Reference  
• STD2 - 198.29 ppm 
• STD3 - 399.28 ppm 
• STD4 - 606.52 ppm 

Length from intake 
From intake to Wetlab: 30.74m. (Pump flow: 6.3m3 h-1). 
 
 
5.5.4.  pCO2 

First comparison of pCO2 data, the gas pressure correction in Fig2 was 
made multiplying the raw data (in ppm) by the Licor gas pressure. Also, 
for SubCtech the pressure difference between the membrane and inside 
Licor needs to be added (Around 15 mbar). 
 
 
Figure 5.5.1: Comparison of pCO2 sensors showing raw data 

Figure 5.5.2: Comparison of pCO2 sensors corrected for gas pressure 
 
Figure 5.5.3: Comparison of Gas pressure at Licor from SubCtech, Pr°CV 
              and GO.  

Figure 5.5.4: Temperature comparison from SubCtech (SBE38 and SBE45), VOS 
              and GO 
  
Figure 5.5.5: Surface Oxygen and Chlorophyll 

Figure 5.5.6: Temperature and salinity from VOS 





6.  STATION CATALOGUE CE17007 
 
Sta-  Cast  Cast   Date      Time   Latitude  Longitude  Bottom  Nuts  CFC  DIC  δ13C
tion   #    Type             (UTC)    °N         °W       Depth    O2         &
  #                                                       (m)    Salt       Alk
————  ————  ————  —————————  —————  ————————  —————————  ——————  ————  ———  ———  ————
  1    1    CTD   29/4/2017  16:41  43.503    -50.0048     68      x          x    x
  2    1    CTD   29/4/2017  21:15  43.335    -49.5818     86.8    x          x    
  3    1    CTD   30/4/2017  00:21  43.2528   -49.3697    558.8    x          x    x
  4    1    CTD   30/4/2017  04:27  43.1931   -49.1528   1045.5    x          x    
  5    1    CTD   30/4/2017  08:32  43.1402   -48.9946   1573.3    x          x    x
  6    1    CTD   30/4/2017  10:03  43.08817  -48.8475   2030      x          x    
  7    1    CTD   30/4/2017  14:51  43.0503   -48.6269   2466      x          x    
  8    1    CTD   30/4/2017  22:32  42.91733  -48.0277   3445      x          x    
  9    1    CTD   1/5/2017   06:03  42.7605   -47.5552   3730      x          x    x
 10    1    CTD   2/5/2017   16:14  42.56317  -46.9335   4100      x          x    
 11    1    CTD   3/5/2017   00:56  42.41467  -46.2832   4662      x          x    x
 11    3    CTD   3/5/2017   23:15  42.43417  -46.2912   4662      x          x    
 12    1    CTD   4/5/2017   05:06  42.24233  -45.6465   4726      x          x    
 13    1    CTD   4/5/2017   13:00  42.07033  -45.0178   4838      x          x    x
 14    1    CTD   4/5/2017   20:38  42.21167  -44.391    4890      x          x    
 15    1    CTD   5/5/2017   04:11  42.39633  -43.7607   4797      x          x    
 20    1    CTD   8/5/2017   17:22  43.32083  -40.601    4816      x          x    x
 21    1    CTD   9/5/2017   03:16  43.50417  -39.9557   4830      x          x    x
 22    1    CTD   9/5/2017   12:02  43.68933  -39.3177   4609      x          x    x
 23    1    CTD   9/5/2017   21:20  43.87267  -38.673    3862      x          x    x
 23    2    CTD   9/5/2017   22:34  43.87283  -38.6728   3862      x    x     x    x
 24    1    CTD   10/5/2017  06:27  44.0565   -38.028    4214      x          x    x
 24    2    CTD   10/5/2017  11:47  44.05667  -38.0282   4214      x          x     x
 25    1    CTD   10/5/2017  18:01  44.24233  -37.3783   4298      x    x     x    x
 26    1    CTD   11/5/2017  01:18  44.42667  -36.732    4147      x          x    
 27    1    CTD   11/5/2017  09:00  44.609    -36.081    4118      x    x     x    x
 28    1    CTD   11/5/2017  16:43  44.79867  -35.4252   3974      x          x    
 29    1    CTD   12/5/2017  00:05  44.9815   -34.7705   4082      x    x     x    x
 31    1    CTD   12/5/2017  10:36  45.34983  -33.4555   3361      x    x     x    
 33    1    CTD   12/5/2017  20:23  45.72067  -32.1278   3191      x    x     x    x
 35    1    CTD   13/5/2017  05:11  46.09117  -30.7955   3375      x    x     x    
 35    2    VPN   13/5/2017  09:26  46.09117  -30.7955   3375                     
 37    1    CTD   13/5/2107  15:36  46.45967  -29.4493   3410      x    x     x    x
 37    2    VPN   13/5/2107  19:15  46.45967  -29.4493   3410                      
 39    1    CTD   13/5/2017  23:40  46.65417  -28.4375   2510      x          x    
 39    2    VPN   13/5/2017  02:30  46.65417  -28.4375   2510                      
 40    1    CTD   14/5/2017  05:57  46.766    -27.7273   1606      x          x    
 41    1    CTD   14/5/2017  11:08  46.879    -27.0163   2040      x    x     x    
 41    2    VPN   14/5/2017  13:10  46.879    -27.0163   2040                      
 42    1    CTD   14/5/2017  17:23  46.99017  -26.3018   3018      x          x    
 43    1    CTD   15/5/2017  00:28  47.10233  -25.5868   3382      x    x     x    
 44    1    CTD   15/5/2017  07:44  47.2145   -24.873    3088      x          x    
 45    1    CTD   15/5/2017  14:25  47.32733  -24.1527   3123      x    x     x    
 46    1    CTD   15/5/2017  20:45  47.43933  -23.433    3730      x          x    
 47    1    CTD   16/5/2017  03:34  47.55117  -22.712    4427      x    x     x    x
 47    2    VPN   16/5/2017  08:25  47.55117  -22.712    4427                      
 48    1    CTD   16/5/2017  11:27  47.66183  -21.9903   4400      x          x    
 48    2    VPN   16/5/2017  15:55  47.66183  -21.9903   4400                      
 49    1    CTD   16/5/2017  19:20  47.77467  -21.2677   4471      x    x     x    
 50    1    CTD   17/5/2017  02:18  47.88667  -20.5408   4351      x          x    
 51    1    CTD   17/5/2017  08:27  47.97     -20.055    4310      x    x     x    
 52    1    CTD   17/5/2017  14:39  48.05767  -19.4355   4573      x          x    
 53    1    CTD   17/5/2017  21:14  48.13567  -18.8678   4374      x    x     x    x
 54    1    CTD   18/5/2017  04:07  48.24433  -18.149    4288      x          x    
 55    1    CTD   18/5/2017  10:59  48.35183  -17.4163   4044      x    x     x    
 56    1    CTD   18/5/2017  17:50  48.45867  -16.6808   4634      x          x    
 57    1    CTD   19/5/2017  01:18  48.567    -15.9437   4535      x    x     x    
 58    1    CTD   19/5/2017  08:54  48.67433  -15.2075   4810      x          x    
 59    1    CTD   19/5/2017  16:22  48.781    -14.4673   4630      x    x     x    
 60    1    CTD   19/5/2017  23:33  48.8895   -13.7233   4505      x          x    
 60    2    ARGO  20/5/2017  03:39  48.8895   -13.7233   4505                      
 61    1    CTD   20/5/2017  06:47  48.98283  -12.9817   2553      x    x     x    
 62    1    CTD   20/5/2017  12:08  49.05833  -12.5465   1290      x          x    
 63    1    CTD   20/5/2017  15:58  49.11     -12.2023   1011      x    x     x    
 64    1    CTD   20/5/2017  19:35  49.13967  -11.8222    827      x          x    
 65    1    CTD   20/5/2017  23:29  49.16867  -11.4442    530      x          x    
 66    1    CTD   21/5/2017  03:01  49.19967  -11.064     182      x          x    
 67    1    CTD   21/5/2017  06:30  49.23183  -10.6497    149      x          x     
—————————————————————————————————————————————————————————————————————————————————————
Notes:  

CTD  - CTD cast for Nutrients, O2 and salinity from all depths, CFCs, DIC 
       and alkalinity from a reduced number of depths at each station. 
VPN  - Vertical Plankton Net tow to 150 m to investigate if the 
       dinoflagellate, Azadinium is present in oceanic waters. The 10 µm 
       mesh net was damaged during cast 47-2 and no sample was collected, 
       the net was subsequently repaired by the crew and redeployed at 
       station 48-2. 
ARGO - deployment of an ARGO float (S/N 7842: Argo identifier  6901926). 




7.  SHIPBOARD PARTICIPANTS 
 
Name                        Discipline                    Institution  
——————————————————————————  ————————————————————————————  ———————————
Croot, Peter. Prof.         Chief Scientist               NUIG 
McGovern, Evin. Dr.         Principal Investigator, DO    MI 
Aparicio, Francisco. Dr.    DO                            NUIG 
Szumski, Tom                Salinity                      MI 
Swartz, Marshall.           CTDO/LADCP/SADCP              WHOI 
Cusack, Caroline. Dr.       CTDO/LADCP/SADCP              MI 
Cronin, Margot. Dr.         Nutrients/Primary UW pCO2     MI 
Gregory, Clynt              Nutrients                     NUIG 
Normandeau, Claire          Nutrients, Carbon Parameters  DAL 
Kerrigan, Liz               Nutrients                     DAL 
Bogner, Boie                CFCs                          GEOMAR 
Merten, Veronique           CFCs                          GEOMAR 
Bruckert, Julia             CFCs                          GEOMAR 
Morris, Ellie               Carbon Parameters             UE 
Sims, Rich                  Carbon Parameters             UE 
Riehl, Lachlan              Carbon Parameters             DAL 
Cheng, Lin                  δ13C DIC                      DAL 
Monteiro da Silva, Ricardo  Secondary Underway pCO2       DAL 
 


Participating Institutions: 

NUIG  National University of Ireland Galway, Galway, Co. Galway, Ireland 
MI    Marine Institute of Ireland, Rinville, Oranmore, Co. Galway, 
      Ireland. 
DAL   Dalhousie University, Canada 
UE    University of Exeter, United Kingdom 
GEO   GEOMAR, Kiel, Germany 
WHOI  Woods Hole Oceanographic Institution, United States of America 
  


                     SHIP’s CREW         
                   Celtic Explorer           RANK
                       CE17007                 
                  ——————————————————  ———————————————————
                  Kenny Downing       Master
                  Garvan Meehan       Chief Engineer
                  Basil Murphy        C/O & Security Off.
                  Barry Hooper        2/O & Safety Off.
                  Dave Stack          2nd Eng
                  Michael Slyne       ETO
                  Frank Kenny         Bosun
                  Jimmy Moran         Cook
                  Shane Horan         Bosun’s Mate
                  Tom Gilmartin       AB Deckhand
                  Martin Goggin       AB Deckhand
                  Anthony English     Technician
                  Cathal Murrin       AB Deckhand
                  Noel O'Driscoll     AB Deckhand
                  Maurice Murphy      Asst. Cook
                  Lukasz Pawlikowski  Technician 
 

 
 

8.  DATA AND SAMPLE STORAGE AND AVAILABILITY 
 

GO-SHIP data is stored in several repositories. Please go to 
https://www.go-ship.org/DataDirect.html for more information or contact 
the Marine Institute, Ireland. 
 




9.  ACKNOWLEDGMENTS 
 
This survey was carried out with the support of the Irish Marine 
Institute and funded under the Marine Research Programme by the Irish 
Government. The CFC and Carbon team activities are funded through the 
AtlantOS project under the European Union's Horizon 2020 research and 
innovation programme grant agreement No. 633211. Support for the Canadian 
Carbon and Nutrient teams was from the Canada Excellence Research Chair 
in Ocean Science and Technology and represents an initial activity of the 
newly formed Ocean Frontier Institute of which the Irish Marine Institute 
and GEOMAR are partners. The SDACP team activities have received funding 
from the European Union’s Horizon 2020 research and innovation programme 
under grant agreement No. 678760 (ATLAS). This output reflects only the 
authors' views and the European Union cannot be held responsible for any 
use that may be made of the information contained therein.  

Special thanks to the Master, Kenny Dowling, and the crew and land 
support team of the RV Celtic Explorer and the GO-SHIP committee.  
 

















CCHDO DATA PROCESSING NOTES

• File Online Andrew Barna
45CE20170427_ctd.nc (download) #418b1
Date: 2021-03-13
Current Status: dataset
Notes
CCHDO-1.0 CF netCDF files converted from ctd exchange file


• File Online Jerry Kappa
74CE170007_JHS_hy1.csv (download) #23634
Date: 2020-10-13
Current Status: unprocessed


• File Submission Jim Swift
74CE170007_JHS_hy1.csv (download) #23634
Date: 2020-10-07
Current Status: unprocessed
Notes
There were two fatal errors in the original 2019-12-13 submitted file for 
74CE170007_hy1.csv: The first line of the file had the values from column 
2 written into column 1 (fixed here) and there was no CTDPRS column. 
Instead, the CTDPRS data were in the DEPTH (depth to bottom) column 
(fixed here). Another error was that the data were in reverse pressure 
order (fixed here). And there were no depth-to-bottom data (not fixed 
here). The file I submitted here is now readable as a WHP-Exchange file. 


• File Merge Carolina Berys
Cruise Report CE17007 A02 GO-SHIP Jan 2020 update .pdf (download) #3322f
Date: 2020-01-24
Current Status: merged

• File Merge Jerry Kappa
45CE20170427_do.txt (download) #c1079
Date: 2020-01-24
Current Status: dataset


• File Submission Jerry Kappa
45CE20170427_do.txt (download) #c1079
Date: 2020-01-24
Current Status: dataset
Notes
The text version of A02_2017's cruise report is ready for the CCHDO 
DataSet.  It includes all of the PI-provided data reports and CCHDO Data 
Processing Notes.





• File Online Carolina Berys
Cruise Report CE17007 A02 GO-SHIP Jan 2020 update .pdf (download) #3322f
Date: 2020-01-22
Current Status: merged


• File Submission Carolina for Caroline Cusack and Peter Croot 
Cruise Report CE17007 A02 GO-SHIP Jan 2020 update .pdf (download) #3322f
Date: 2020-01-22
Current Status: merged
Notes
Cruise Report received via email on 2020-01-22


• File Merge Jerry Kappa
45CE20170427_do.pdf (download) #ed4db
Date: 2020-01-14
Current Status: dataset


• File Submission Jerry Kappa
45CE20170427_do.pdf (download) #ed4db
Date: 2020-01-14
Current Status: dataset
Notes
The .pdf version of A02_2017's cruise report is ready to be added to the 
DataSet.  It includes all of the PI-provided data reports plus a CCHDO 
summary page and data processing notes.


• File Online Carolina Berys
74CE170007_hy1.csv (download) #78dc3 
Date: 2019-12-13 
Current Status: unprocessed


• File Submission Carolina for ADam Leadbetter
74CE170007_hy1.csv (download) #78dc3 
Date: 2019-12-13 
Current Status: unprocessed 
Notes
Updated file submitted via email 2019-12-13. Note: TOxN is total oxidized 
nitrogen (see 
https://www.researchgate.net/publication/331655704_A_rare_intercomparison
_of_nutrient_analysis_at_sea_Lessons_learned_and_recommendations_to_enhan
ce_comparability_of_open-ocean_nutrient_data)


• File Online Carolina Berys
74CE170007_hy1.csv (download) #1fd0f 
Date: 2019-12-12 
Current Status: unprocessed


• File Submission Adam Leadbetter
74CE170007_hy1.csv (download) #1fd0f 
Date: 2019-12-12 
Current Status: unprocessed


• File Merge CCHSIO
45CE_20170427_ct1.zip (download) #e26d1 
Date: 2019-01-16 
Current Status: merged


• Merged CTD data into Dataset CCHSIO 
Date: 2019-01-16 
Data Type: CTD 
Action: Merge 
Note: 
    2017 45CE20170427 processing - CTD/merge - 
CTDPRS,CTDTMP,CTDSAL,CTDOXY

2019-01-16

CCHSIO


Submission

filename              submitted by     date       id  
--------------------- ---------------  ---------- -----
45CE_20170427_ct1.zip Adam Leadbetter  2018-12-11 14251

Changes
-------

45CE_20170427_ct1.zip
        - added units comments
        - added cruise information as commentes
        - DEPTH is depth of the CTD. Therefore, removed bottom depth from 
          header.  Put it as a comment because this is not bottom depth, 
          but it is the max depth of the CTD
        - Changed EXPOCODE from 45CE_20170427 to 45CE20170427
        - Removed leading 0s from STNNBR
        - Changed EXPOCODE from 45CE_20170427 to 45CE20170427
        - Renamed files to match EXCHANGE standard. Put original file 
name in file as a comment.

Conversion
----------

file                    converted from       software               
----------------------- -------------------- -----------------------
45CE20170427_nc_ctd.zip 45CE20170427_ct1.zip hydro 0.8.2-48-g594e1cb


Updated Files Manifest
----------------------

file                    stamp            
----------------------- --------------
45CE20170427_ct1.zip    20190116CCHSIO
45CE20170427_nc_ctd.zip 20190116CCHSIO

:Updated parameters: CTDPRS,CTDTMP,CTDSAL,CTDOXY

opened in JOA 5.2.1 with no apparent problems:
     45CE20170427_ct1.zip
     45CE20170427_nc_ctd.zip

opened in ODV with no apparent problems:
     45CE20170427_ct1.zip


• File Online Carolina Berys
45CE_20170427_ct1.zip (download) #e26d1 
Date: 2018-12-18 
Current Status: merged


• File Submission Adam Leadbetter
45CE_20170427_ct1.zip (download) #e26d1 
Date: 2018-12-11 
Current Status: merged 
Notes
45CE20170427

Processed CTD cast data


