A.   Cruise Report:  S04I

A.1. Highlights
                     WHP Cruise Summary Information

            WOCE line designation  S04I
Expedition designation (ExpoCode)  320696_3
 Chief scientists and affiliation  Thomas Whitworth III and James H. Swift*
                             Ship  RVIB NATHANIEL B. PALMER 
                     Cruise dates  1996.MAY.03 - 1996.JUL.04
                    Ports of call  Cape Town, S. Africa - Hobart, Australia
               Number of stations  108 full-depth CTD stations
                                              58° 0.23' S
            Geographic boundaries  20° 0.34' E            120° 0.08' E
                                              65° 41.97' S
     Floats and drifters deployed  17 ALACE floats
   Moorings deployed or recovered  9 self-reporting current meter moorings

      *Thomas Whitworth III        James H. Swift
       Department of Oceanography  Scripps Institution of Oceanography
       Texas A&M University        University of California, San Diego
       College Station, TX, 77843  La Jolla, CA, 92093
       twhitworth@tamu.edu         jswift@ucsd.edu

            Authors  S. Rutz,      D. Chipman,  M. Mensch,
                     F. Delahoyd,  D. Breger,   R. Key,
                     E. Peltola,   T. Whitworth


WOCE Hydrographic Program Line S04I was conducted on the RVIB NATHANIEL B. 
PALMER on voyage S229 from 3 May to 4 July, 1996.  The voyage began in Cape 
Town, Republic of South Africa, and ended in Hobart, Australia.  Co-Chief 
Scientists for the cruise were Thomas Whitworth III/TAMU and James H. Swift/SIO.

WHP leg S04I was a cooperative effort among the PIs listed in Table 1.  The 
members of the scientific party are listed in Table 2.   

Table 1. Principal Investigators for WOCE S04I

            Component         Principal Investigator  Institution
            ----------------- ----------------------  -----------
            CTD/Hydrography   J. Swift                SIO
            CFCs              W. Smethie/M. Warner    LDEO/UW
            Tritium, 3He, 18O P. Schlosser            LDEO
            CO2               T. Takahashi            LDEO
            Alkalinity        F. Millero              Miami
            14C               R. Key                  Princeton
            current meters    W. Nowlin/T. Whitworth  TAMU
            Transmissometer   W. Gardner              TAMU
            LADCP*            E. Firing/P. Hacker     UH
            ALACE floats      R. Davis                SIO

* The LADCP was lost during a test, therefore no LADCP data are reported for 
  this cruise.


Table 2.  Participants on WOCE S04I

Participant       Affiliation  Responsibility
----------------  -----------  -----------------------------------------------
Isabelle Ansorge  UCT          CTD console, sampling, salinities
Dee Breger        LDEO         Tritium, 3He, 18O
Christie Campbell ASA          deck ops, sampling, hazardous waste, salinities
Kent Chen         ASA          sampling, oxygen, NBP computer
David Chipman     LDEO         CO2
Scott Colburn     ASA          PDR, sampling, NBP ET
Craig Hallman     ODF          deck ops, sampling, oxygen
Steve Covey       UW           CFCs
Frank Delahoyde   ODF          ODF systems, data q.c.
Bob Key           PU           14C, gadfly
Leonard Lopez     ODF          deck ops, oxygen
Guy Mathieu       LDEO         CFCs
Carl Mattson      ODF          TIC, deck supv., ET
Rod McCabe        ASA          sampling, NBP computer
Manfred Mensch    LDEO         CFCs
Stacey Morgan     ODF          nutrients
Jim Noyes         SIO          CTD console, sampling
Alex Orsi         UW           CTD console, sampling, analysis
Ron Patrick       ODF          deck supv., bottle q.c.
Esa Peltola       UM           Alkalinity
Erik Quiroz       TAMU         nutrients
Blaine Reynolds   ASA          PDR, rosette prep., NBP ET
Stephany Rubin    LDEO         CO2
Steve Rutz        TAMU         watch leader., CTD console, sampling, ADCP
Buzz Scott        ASA          deck ops., salinities, MT
Colm Sweeney      LDEO         CO2
Jim Swift         SIO          watch leader., CTD console, sampling, analysis
Mark Talkovic     ASA          deck ops., salinities, MT
Tom Whitworth     TAMU         indirection, analysis
Kevin Wood        ASA          deck ops., sampling, MPC
 

ASA:  Antarctic Support Associates     UM:   University of Miami (RSMAS)
      61 Inverness Dr. East, Suite 300       4600 Rickenbacker Cswy.
      Englewood, CO 80112                    Miami, FL 33149
SIO:  Scripps Instit. of Oceanog.      LDEO: Lamont-Doherty Earth Observatory
      Univ. of Calif.-San Diego              Columbia University
      La Jolla, CA                           Palisades, NY 10964
TAMU: Texas A&M University             UW:   University of Washington
      Dept. of Oceanography                  School of Oceanography
      College Sta. TX 77843                  Seattle, WA 98195
ODF:  Ocean Data Facility              UCT:  University of Cape Town
      Scripps Instit. of Oceanog.            Department of Oceanography
      9500 Gilman Dr.                        Rondebosch, Cape Town
      La Jolla, CA 92093                     South Africa
PU:   Princeton University    
      Dept. of Geosciences    
      207 Guyot Hall    
      Princeton, N.J. 08544    


A2.  Scientific Program Summary

Narrative

The cruise constituted the Indian Ocean portion of WOCE line S04, a meridional 
circumnavigation of Antarctica at a nominal latitude of 60°S.  This segment 
covered the longitudes 20°E to 120°E.  

After departure from Cape Town, a bottom-tracking course was set to provide 
about 8 hours of depths along the 200-m isobath to calculate the offset between 
the ship's gyro and the underway Acoustic Doppler Current Profiler (ADCP).  Upon 
reaching deep water, the CTD wire was lowered to 5500 m wire out to tension the 
wire on the winch, and subsequently, two test CTD casts were made to choreograph 
the procedures for launching and recovering the package in the unfamiliar 
setting of the Palmer's Baltic Room.

At 0330 on 7 May, the Palmer turned back toward South Africa to seek medical 
attention for a crew member.  The ship was diverted to the naval base at 
Simonstown where fuel was available, and the morning and afternoon of May 10 
were spent getting the crewman treated and refueling.  Bottom-tracking for the 
ADCP calibration was repeated into and out of Simonstown.

On Sunday, 12 May, a third CTD test cast was being recovered when a sudden wave 
lifted the rosette out of the water and then dropped it.  The wire parted at the 
sheave, and the entire package was lost.  The only piece of equipment without 
back-up was the lowered ADCP unit belonging to the University of Hawaii.  
Subsequent days were spent preparing a second rosette unit, considering 
alternative launch and recovery procedures and defining guidelines for the sea 
state in which CTD operations could be conducted on the Palmer.  Because the 
Palmer reacted differently from UNOLS vessels we were accustomed to, the planned 
cruise track was modified to lie in, or closer to the ice where swell would be 
less of a problem.

Station 1 was occupied at 58°S, 20°E and the first station line was run 
southeast to Gunnerus Ridge, about 50 miles south of the ice edge.  Station 
positions for the cruise are shown in Fig. 1.  During the transit to station 1 
and continuing to 58°S, 17 ALACE floats were launched.  Details are provided in 
Table 3.  Stations across the Enderby Abyssal Plain trended east-northeast from 
66°S at 33°E, to 61°S at 83°E on the Kerguelen Plateau.  A line of stations 
(35-42) was made north from the 500-m isobath on the continental slope at 53°E, 
and three self-reporting current meters were deployed along the slope.  Details 
of the current meter deployments are given in Table 4.  A line of stations (65-
72) extending east from the crest of the Kerguelen Plateau was made at about 59°
S, and three more current meters were placed in the boundary current on the 
eastern flank of the Plateau.  On June 8, after station 72, science operations 
were suspended for seven days when the Palmer was diverted to Mirnyi Station in 
the Davis Sea to deliver emergency food supplies.  

On June 14, the Palmer left Mirnyi and began a line of stations (73-86) from the 
shelf break of the Davis Sea to Kerguelen Plateau.  One current meter was placed 
near the 3000-m isobath north of the Antarctic Continental Slope, and two were 
deployed at the southern end of Kerguelen Plateau.  The zonal line of stations 
at a nominal latitude of 62°S was resumed at 90°E.  Ice conditions, fuel and 
time considerations necessitated 45-mile station separation for most of the 
final 22 stations, which terminated with station 108 at 120°E.

Summary Information

108 full-depth CTD stations were made exclusive of test stations at the 
beginning of the cruise and a dedicated CFC archive-sample cast at the end of 
the cruise. Nine self-reporting current meters and 17 ALACE floats were deployed


Table 3.  ALACE deployments on WOCE S04I

Ser# Type Lat       Long      Time/Date     Ser# Type Lat       Long      Time/Date
---- ---- --------  --------  ---------     ---- ---- --------  --------  ----------
628  T    37-58.3S  20-16.1E  2056Z 5/4     641  Std  47-59.4S  19-12.0E  2221Z 5/13
346  Std  38-59.1S  21-46.4E  0610Z 5/5     642  Std  49-32.6S  19-16.5E  0700Z 5/14
629  T    39-59.1S  21-46.1E  1546Z 5/5     643  Std  50-59.8S  19-20.7E  1458Z 5/14
559  Std  40-59.4S  21-42.2E  2118Z 5/5     607  CTD  51-58.7S  19-23.8E  2045Z 5/14
634  Std  41-58.8S  21-38.5E  0228Z 5/6     644  Std  52-59.8S  19-26.4E  0224Z 5/15
566  Std  43-29.9S  21-32.9E  1040Z 5/6     608  CTD  54-30.0S  19-31.7E  1035Z 5/15
604  CTD  44-59.9S  21-27.3E  2042Z 5/6     645  Std  55-59.4S  19-47.2E  1855Z 5/15
640  Std  45-59.9S  19-06.5E  1118Z 5/13    609  CTD  57-30.0S  19-58.6E  0331Z 5/16
605  CTD  47-00.0S  19-09.7E  1651Z 5/13        

*T = temperature,    Std = Standard,    CTD = cond/temp/depth


Table 4.  Self-reporting current meter deployments

          CMﬂ              
              serial# time   date        latitude   longitude  depth   MAB*
          --- ------- -----  ---------   ---------  ---------  ------  ---
          A                
              26935   0732Z  28 May 96   65-22.8 S  53-14.2 E  1740 m  50
          B                 
              26939   1125Z  28 May 96   65-14.0 S  53-06.5 E  1900 m  50
          C                 
              26936   1904Z  28 May 96   65-07.0 S  52-59.6 E  2260 m 100
          D                 
              26937   1706Z   6 June 96  59-42.9 S  84049.9 E  2020 m  50
          E                 
              26941   2209Z  6 June 96   59-40.6 S  85-07.9 E  3080 m  50
          F                 
              26943   2231Z   6 June 96  59-40.3 S  85-10.9 E  4225 m  50
          G                 
              26944   1331Z  16 June 96  64-03.8 S  92-21.5 E  3275 m 100
          H                 
              26938   0614Z  19 June 96  63-00.0 S  85-00.0 E  3058 m  50
          I                 
              26940   1212Z  19 June 96  62-59.6 S  84-31.5 E  2740 m  50
 
          ﬂ letters correspond to Fig. 1
          * MAB = meters above bottom








                    World Ocean Circulation Experiment
                         Southern Indian Ocean S4I
                      R/V Nathaniel B. Palmer NBP96-3
                            3 May - 4 July 1996
           Cape Town, South Africa - Hobart, Tasmania, Australia
                            Expocode:  320696_3

                           Co-Chief Scientists:
                Dr. Thomas Whitworth (Texas A&M University)
         Dr. James H. Swift (Scripps Institution of Oceanography)


                             S4I Cruise Track

                     Oceanographic Data Facility (ODF)
                            Final Cruise Report
                               1 August 2003

                            Data Submitted by:
                        Oceanographic Data Facility
                    Scripps Institution of Oceanography
                          La Jolla, CA 92093-0214
                            http://odf.ucsd.edu



DESCRIPTION OF MEASUREMENT TECHNIQUES AND CALIBRATIONS


1.  Basic Hydrography Program

The basic hydrography program consisted of salinity, dissolved oxygen and
nutrient (nitrite, nitrate, phosphate and silicate) measurements made from
bottles taken on CTD/rosette casts, plus pressure, temperature, salinity
and dissolved oxygen from CTD profiles.  109 CTD/rosette casts were made at
108 stations, usually to within 5-15 meters of the bottom.  Station 2 cast
1 was aborted at the surface because of signal failure at 322m on the down-
cast; it is not otherwise mentioned in this release or documentation.
Water was found inside the CTD case; after repairs, station 2 cast 2 was
successfully accomplished.

17 ALACE floats were deployed during the transit from Cape Town to station 1.  
9 expendable current meters were deployed following 8 stations along the cruise.

The R/V Nathaniel B. Palmer departed from Cape Town, South Africa on May 3,
1996.  One test cast was accomplished on May 6; on May 7, the ship turned
back toward South Africa to seek medical attention for a crew member.  The
ship docked at the naval base at Simonstown on May 10, departing later the
same day to resume the expedition.  2 more test casts were done during the
transit.  During the recovery of the second of these casts, a rogue wave
lifted the rosette out of the water and then dropped it.  The wire parted
at the sheave, and the rosette package was lost.  A backup rosette was
prepared and used for the remainder of the cruise.

108 CTD/Rosette stations were occupied between May 16 and June 27 along the
nominal S4I line (60 deg.S), between 58-66  deg.S latitude and 20-120 deg.E
longitude.  An additional line (stations 35-42) was made northward from the
500m isobath on the continental slope at 53 deg.E back to the main track.
There was a 6.5-day (June 8-14) diversion from the track after station 72
to deliver emergency food supplies to Mirnyy Station in the Davis Sea.
After Mirnyy, an extra line (stations 73-86) was run northward, then
westward, from the shelf break of the Davis Sea back toward the S4I line.
The cruise ended in Hobart, Tasmania, Australia on July 4, 1996.

3655 bottles were tripped resulting in 3651 usable bottles.  Any problems
encountered during data acquisition or processing are described later in
this document.  The resulting data set met and in many cases exceeded WHP
specifications.  The distribution of samples is illustrated in Figures 1.0,
1.1 and 1.2.


Figure 1.0  S4I sample distribution, stas 1-34.
Figure 1.1  S4I sample distribution, stas 35-72.
Figure 1.2  S4I sample distribution, stas 73-108.


2.  Water Sampling Package

Hydrographic casts were performed with a rosette system consisting of a
36-bottle rosette frame (ODF), a General Oceanics (GO) 36-place pylon
(Model 2216) and 36 10-liter PVC bottles (ODF).  Underwater electronic
components consisted of an ODF-modified NBIS Mark III CTD (ODF #3) and
associated sensors, SeaTech transmissometer (TAMU) and Benthos pinger
(Model 2216).  The CTD was mounted horizontally along the bottom of the
rosette frame, with the transmissometer, a SensorMedics dissolved oxygen
sensor and an FSI secondary PRT sensor deployed next to the CTD.  The
pinger was monitored during a cast with a precision depth recorder (PDR) in
the ship's laboratory.  The rosette system was suspended from a three-
conductor 0.322" electro-mechanical cable.  Power to the CTD and pylon was
provided through the sea cable from the ship.  Separate conductors were
used for the CTD and pylon signals.  The transmissometer, dissolved oxygen
and secondary temperature were interfaced with the CTD, and their data were
incorporated into the CTD data stream.  Deep Sea Reversing Thermometers
(DSRTs) were used occasionally on this leg to monitor for CTD pressure or
temperature drift.

Three rosette test casts were performed prior to station 1: 998 (6 May),
997 (11 May) and 996 (12 May).  During retrieval on the third test cast
(996), a wave caught the rosette, and the wire jumped the sheave and broke.
The rosette, bottles and all associated electronics were lost.  The only
instruments that did not have backup units were the UH LADCP and an ODF
altimeter.  A spare altimeter was used during stations 1-5 and 8-10, but was 
removed for the rest of the cruise; it never worked properly and was
identified as the source of the degraded signal seen during the up-cast for
station 5.

The deck watch prepared the rosette approximately 45 minutes prior to each
cast.  All valves, vents and lanyards were checked for proper orientation.
The bottles were cocked and all hardware and connections rechecked.  Time,
position and bottom depth were logged by the console operator at arrival on
station.  The rosette system was deployed from the Palmer's main deck out
of the starboard-side Baltic Room, a protected rosette room and winch shed
with an external door and an extension boom.  The deployment door to the
Baltic Room was opened after the ship had finished positioning, which
sometimes entailed clearing a hole in the ice.  Deployment was assisted by
tag lines threaded through rings on the rosette for stabilization.

Each rosette cast was lowered to within 5-15 meters of the bottom, unless
the bottom return from the pinger was extremely poor.  As noted already, no
altimeter data were available to assist with bottom approaches after
station 5.

Bottles on the rosette were each identified with a unique serial number.
Usually these numbers corresponded to the pylon tripping sequence, 1-36,
where the first (deepest) bottle tripped was bottle #1.  Bottle #8 had
repeated drain valve leakage problems and was replaced with bottle #37
(stations 13-25 and 35-47), Ocean Instrument Tech. (OIT) test bottle #61
(stations 26-34) and Antarctic Support Associates (ASA) test bottle #63
(stations 48-108).  Bottle #4 was missing (apparently imploded) after
station 77, and was replaced with bottle #39 for stations 78-108.  GO test
bottle #62 replaced bottles #10 (stations 26-28) and #6 (stations 82-83).

Averages of CTD data corresponding to the time of bottle closure were
associated with the bottle data during a cast.  Pressure, depth,
temperature, salinity and density were immediately available to facilitate
examination and quality control of the bottle data as the sampling and
laboratory analyses progressed.

Recovering the package at the end of deployment was essentially the reverse
of the launching with the additional use of air-tuggers for added
stabilization.  The rosette was placed onto the Baltic Room deck, then the
deployment door was closed prior to sampling.  The bottles and rosette were
examined before samples were taken, and any unusual situations or
circumstances were noted on the sample log for the cast.  Seawater froze on
rosette bottles several times during recovery, but quickly thawed in the
Baltic Room.  There was never any evidence of water freezing in the bottles
or spigots.

Routine CTD maintenance included soaking the conductivity and CTD O2
sensors in distilled water between casts to maintain sensor stability.
Beginning at station 20, the distilled water was replaced by salt water ~1
hour prior to deployment to reduce the possibility of sensors freezing
before entering the water.  This preventive measure was not totally
successful, and freezing did occur during deployment on some casts.  When
freezing was detected by the console operator, the rosette was lowered to
30-80 meters to thaw the sensors, then raised back to the surface.

Rosette maintenance was performed on a regular basis.  O-rings were changed
as necessary and bottle maintenance was performed each day to insure proper
closure and sealing.  Valves were inspected for leaks and repaired or
replaced as needed.

The transmissometer windows were cleaned prior to deployment approximately
every 20 casts.  The air readings were noted in the TAMU transmissometer
log book after each cleaning.  Transmissometer data were monitored for
potential problems during every cast, but were not processed by ODF beyond
initial block averaging.

The starboard-side Baltic Room Markey winch was used throughout the cruise.
Only one sea cable retermination was necessary, prior to station 57.


3.  Underwater Electronics Packages

CTD data were collected with a modified NBIS Mark III CTD (ODF #3).  This
instrument provided pressure, temperature, conductivity and dissolved O2
channels, and additionally measured a second temperature with an FSI 
oceantemperature module (OTM) as a calibration check.  An FSI ocean pressure
module (OPM) was substituted in place of the secondary temperature OTM for
four casts.  Other data channels included elapsed-time, several power
supply voltages and transmissometer.  The instrument supplied a 15-byte
NBIS-format data stream at a data rate of 25 Hz.  Modifications to the
instrument included revised pressure and dissolved O2 sensor mountings;
ODF-designed sensor interfaces for O2, FSI-OTM PRT and transmissometer;
implementation of 8-bit and 16-bit multiplexer channels; an elapsed-time
channel; instrument ID in the polarity byte and power supply voltages
channels.

Table 3.0 summarizes the serial numbers of instruments and sensors used
during S4I.


Table 3.0 S4I Instrument/Sensor Serial Numbers

                    | ODF  |  SensorMedics   |     SeaTech    
         Station(s) | CTD+ |  Model 147737   | Transmissometer
                    | ID#  |  Oxygen Sensor  |     (TAMU)     
         -----------|------|-----------------|----------------
         1-31,39-61 |  3a  |                 |                
         -----------|------|                 |                
           32-38    |  3b  |                 |                
         -----------|------|                 |                
           62-100   |  3c  |                 |                
         -----------|------|     5-02-22     |      151D      
          101-102   |  3d  |                 |                
         -----------|------|                 |                
          103-106   |  3e  |                 |                
         -----------|------|                 |                
          107-108   |  3f  |                 |                
         -----------|------|-----------------|----------------
         + See table below for ODF CTD serial numbers         


ODF CTD #3 sensor serial numbers:

  NBIS    |       Pressure        |        Temperature        | Conductivity
 MKIIIB   |      Paine Model      |    PRT1     | PRT2/(PRS2) |             
   CTD    |     211-35-440-05     |  Rosemount  |     FSI     |  NBIS Model 
(ODF-ID#) | strain gage/0-8850psi | Model 171BJ |  OTM/(OPM)  | 09035-00151 
----------|-----------------------|-------------|-------------|-------------
   3a     |                       |             |             |     E55     
----------|                       |             |  OTM/1320T  |-------------
   3b     |                       |             |             |     P42     
----------|                       |             |-------------|-------------
   3c     |                       |             |  OTM/1322T  |             
----------|         77011         |    14373    |-------------|             
   3d     |                       |             |  OTM/1321T  |             
----------|                       |             |-------------|     O17     
   3e     |                       |             | (OPM/1326P) |             
----------|                       |             |-------------|             
   3f     |                       |             |  OTM/1320T  |             


The CTD pressure sensor mounting had been modified to reduce the dynamic
thermal effects on pressure.  The sensor was attached to a section of
coiled, oil-filled stainless-steel tubing that was connected to the end-cap
pressure port.  The transducer was also insulated.  The NBIS temperature
compensation circuit on the pressure interface was disabled; all thermal
response characteristics were modeled and corrected in software.

The O2 sensor was deployed in a pressure-compensated holder assembly
mounted separately on the rosette frame and connected to the CTD by an
underwater cable.  The O2 sensor interface was designed and built by ODF
using an off-the-shelf 12-bit A/D converter.  The transmissometer interface
was a similar design.

Although the secondary temperature sensor was located within 6 inches of
the CTD conductivity sensor, it was not sufficiently close to calculate
coherent salinities.  It was used as a secondary temperature calibration
reference rather than as a redundant sensor, with the intent of eliminating
the need for mercury or electronic DSRTs as calibration checks.  Three
secondary temperature sensors were interchanged during S4I.

The General Oceanics (GO) 1016 36-place pylon was used in conjunction with
an ODF-built deck unit and external power supply instead of a GO pylon deck
unit.  This combination provided generally reliable operation and positive
confirmation.  The pylon emitted a confirmation message containing its
current notion of bottle trip position, which could be useful in sorting
out mis-trips.  The acquisition software averaged CTD data corresponding to
the rosette trip as soon as the trip was initiated until the trip
confirmed, typically 3.5 +/- 1 seconds on S4I.

There were 13 random bad trip confirmations during S4I; 12 of these were
noticed in a timely manner by the console operator and re-tripped
successfully.  3 odd trip confirmations resulted in open bottles at the
surface.  There were 255 other odd trip confirmations, most of which were
duplicates of valid confirmations or in place of normal confirmations.  2
casts (stas 78 and 79) were re-started mid-up-cast because of pylon
communication or confirmation problems.  2 casts (stas 40 and 79) had trip
confirmations that were off by 1 level on many or all bottles.  2 other
casts (stas 52 and 56) confirmed normally but returned to the surface with
the first two bottles tripped at unknown depths, and the rest 2 trip levels
deeper than expected.  The bottles for these casts were matched up to the
correct CTD trip depths after the casts, by comparison of CTD and bottle
data water properties.  Bad or odd confirmations that affected bottle trips
are documented in Appendix D.


4.  Navigation and Bathymetry Data Acquisition

Navigation data were acquired from the ship's Ashtech GPS receiver via the
network, which reported full P-code position information.  Data were logged
automatically at one-minute intervals by one of the Sun SPARCstations.
Underway bathymetry was logged manually from the 12 kHz Raytheon/EPC PDR at
five-minute intervals (or when possible in the ice), then corrected
according to Carter [Cart80] and merged with the navigation data to provide
a time-series of underway position, course, speed and bathymetry data.
These data were used for all station positions, PDR depths and bathymetry
on vertical sections.


5.  CTD Data Acquisition, Processing and Control System

The CTD data acquisition, processing and control system consisted of a Sun
SPARCstation LX computer workstation, ODF-built CTD and pylon deck units,
CTD and pylon power supplies, and a VCR recorder for real-time analog
backup recording of the sea cable signal.  The Sun system consisted of a
color display with trackball and keyboard (the CTD console), 18 RS-232
ports, 2.5 GB disk and 8mm cartridge tape.  Two other Sun SPARCstation LX
systems were networked to the data acquisition system, as well as to the
rest of the networked computers aboard the Palmer.  These systems were
available for real-time CTD data display and provided for hydrographic data
management and backup.  Two HP 1200C color inkjet printers provided
hardcopy capability from any of the workstations.

The CTD FSK signal was demodulated and converted to a 9600 baud RS-232C
binary data stream by the CTD deck unit.  This data stream was fed to the
Sun SPARCstation.  The pylon deck unit was connected to the Sun LX through
a bi-directional 300 baud serial line, allowing bottle trips to be
initiated and confirmed by the data acquisition software.  A bitmapped
color display provided interactive graphical display and control of the CTD
rosette sampling system, including real-time raw and processed CTD data,
navigation, winch and rosette trip displays.

The CTD data acquisition, processing and control system was prepared by the
console watch a few minutes before each deployment.  A console operations
log was maintained for each deployment, containing a record of every
attempt to trip a bottle as well as any pertinent comments.  Most CTD
console control functions, including starting the data acquisition, were
initiated by pointing and clicking a trackball cursor on the display at
icons representing functions to perform.  The system then presented the
operator with short dialog prompts with automatically generated choices
that could either be accepted as defaults or overridden.  The operator was
instructed to turn on the CTD and pylon power supplies, then to examine a
real-time CTD data display on the screen for stable voltages from theunderwater 
unit. Once this was accomplished, the data acquisition and processing were begun 
and a time and position were automatically logged for the beginning of the cast. 
A backup analog recording of the CTD signal on a VCR tape was started at the 
same time as the data acquisition. A rosette trip display and pylon control 
window popped up, giving visual confirmation that the pylon was initializing 
properly. Various plots and displays were initiated. When all was ready, the 
console operator informed the deck watch by radio. 

Once the deck watch had deployed the rosette, it was immediately lowered
without pausing at the sea surface.  The deck watch informed the console
operator that the rosette was on its way down (also confirmed by the
computer displays).  If the console operator noticed that sensors were
frozen on entry, the package was stopped at 30-80 meters, then raised to
just below the surface to allow the sensors to thaw.  The console operator
or deck watch leader then provided the winch operator with a target depth
(wire-out) and maximum lowering rate, normally 60-70 meters/minute for this
package.  The package built up to the maximum rate during the first few
hundred meters, then optimally continued at a steady rate without any stops
during the down-cast.

The console operator examined the processed CTD data during descent via
interactive plot windows on the display, which could also be run at other
workstations on the network.  Additionally, the operator decided where to
trip bottles on the up-cast, noting this on the console log.  The PDR was
monitored to insure the bottom depth was known at all times.

The deck watch leader assisted the console operator by monitoring the
rosette's distance to the bottom using the difference between the rosette's
pinger signal and its bottom reflection displayed on the PDR.  No altimeter
was available to assist with bottom approaches.  The winch speed was
usually slowed to ~30 meters/minute during the final approach.  The winch
and PDR displays allowed the watch leader to refine the target depth
relayed to the winch operator and safely approach to within 5-15 meters of
the bottom.

Bottles were closed on the up-cast by pointing the console trackball cursor
at a graphic firing control and clicking a button.  The data acquisition
system responded with the CTD rosette trip data and a pylon confirmation
message in a window.  A bad or suspicious confirmation signal typically
resulted in the console operator repositioning the pylon trip arm via
software, then re-tripping the bottle, until a good confirmation was
received.  All tripping attempts were noted on the console log.  The
console operator then instructed the winch operator to bring the rosette up
to the next bottle depth.  The console operator was also responsible for
generating the sample log for the cast.

After the last bottle was tripped, the console operator directed the deck
watch to bring the rosette on deck.  It was sometimes necessary to close
the surface bottles "on the fly" due to a risk of slack wire at higher sea
states.  Once the rosette was on deck, the console operator terminated the
data acquisition and turned off the CTD, pylon and VCR recording.  The VCR
tape was filed.  Usually the console operator also brought the sample log
to the rosette room and served as the sample cop.


6.  CTD Data Processing

ODF CTD processing software consists of over 30 programs running under the
Unix operating system.  The initial CTD processing program (ctdba) is used
either in real-time or with existing raw data sets to:

o   Convert raw CTD scans into scaled engineering units, and assign
    the data to logical channels
o   Filter various channels according to specified filtering
    criteria
o   Apply sensor- or instrument-specific response-correction models
o   Provide periodic averages of the channels corresponding to the
    output time-series interval
o   Store the output time-series in a CTD-independent format


Once the CTD data are reduced to a standard-format time-series, they can be
manipulated in various ways.  Channels can be additionally filtered.  The
time-series can be split up into shorter time-series or pasted together to form 
longer time-series.  A time-series can be transformed into a pressure-
series, or into a larger-interval time-series.  The pressure calibration
corrections are applied during reduction of the data to time-series.
Temperature, conductivity and oxygen corrections to the series are
maintained in separate files and are applied whenever the data are
accessed.

ODF data acquisition software acquired and processed the CTD data in real-
time, providing calibrated, processed data for interactive plotting and
reporting during a cast.  The 25 Hz data from the CTD were filtered,
response-corrected and averaged to a 2 Hz (0.5-second) time-series.  Sensor
correction and calibration models were applied to pressure, temperature,
conductivity and O2.  Rosette trip data were extracted from this time-
series in response to trip initiation and confirmation signals.  The
calibrated 2 Hz time-series data, as well as the 25 Hz raw data, were
stored on disk and were available in real-time for reporting and graphical
display.  At the end of the cast, various consistency and calibration
checks were performed, and a 2-db pressure-series of the down-cast was
generated and subsequently used for reports and plots.

CTD plots generated automatically at the completion of deployment were
checked daily for potential problems.  The two PRT temperature sensors were
inter-calibrated and checked for sensor drift.  The CTD conductivity sensor
was monitored by comparing CTD values to check-sample conductivities, and
by deep theta-salinity comparisons between down- and up-casts as well as
adjacent stations.  The CTD O2 sensor was calibrated to check-sample data.

Two casts (stations 30 and 31) exhibited an unacceptable level of primary
PRT temperature noise which was traced to a water leak in the sensor
turret.  The secondary PRT temperature was used in these cases.  CTD
salinity for these casts is noisier than usual because of the greater
distance of the secondary PRT from the conductivity sensor, and because of
potential noise induced on the conductivity sensor by the flooded turret.

There was a high level of conductivity drift during stations 32-38, which
used a new and apparently defective conductivity sensor, and during
stations 55-61, just before the original conductivity sensor was replaced
with yet another new sensor.  Since down- and up-cast conductivities were
very different for these casts, it was necessary to use the up-casts for
these stations, where bottle-CTD differences could be used to determine
pressure-dependent conductivity corrections for each cast individually.

A few casts exhibited conductivity offsets due to biological or particulate
artifacts.  Some casts were subject to noise in the data stream caused by
sea cable or slip-ring problems, or by moisture in the interconnect cables
between the CTD and external sensors (i.e. O2).  Intermittent noisy data
were filtered out of the 2 Hz data using a spike-removal filter.  A least-
squares polynomial of specified order was fit to fixed-length segments of
data.  Points exceeding a specified multiple of the residual standard
deviation were replaced by the polynomial value.

Density inversions can be induced in high-gradient regions by ship-
generated vertical motion of the rosette.  Detailed examination of the raw
data shows significant mixing occurring in these areas because of "ship
roll".  In order to minimize density inversions, a ship-roll filter was
applied to all casts during pressure-sequencing to disallow pressure
reversals.  The first few seconds of in-water data were excluded from the
pressure-series data, since the sensors were still adjusting to the going-
in-water transition.

Pressure intervals with no time-series data can optionally be filled by
double-quadratic interpolation/extrapolation.  Most pressure intervals
missing/filled during this leg were within the top 0-4 db, caused by
chopping off going-in-water transition data during pressure-sequencing.
However, there were a number of casts where temperature or conductivity
sensors froze in transit from the deck into the water.  Ideally, these were
noticed by the console operator, and the casts were returned to near-
surface water and restarted after thawing.  However, a number of casts with
freezing problems were not noticed.  At the request of one of the co-chief
scientists, down-cast data were extrapolated from the "thaw" point back to
the surface whenever there was a clear, stable mixed layer.  The resulting
data were compared to original down-cast data from the un-frozen sensor,
up-cast data from the same cast and density profiles.

When the down-cast CTD data have excessive noise, gaps or offsets, the up-
cast data are used instead.  This also applied to frozen-sensor casts where
down-casts could not be extrapolated without distortion, or where sensors
remained frozen below the mixed layer.  CTD data from down- and up-casts
are not mixed together in the pressure-series data because they do not
represent identical water columns (due to ship movement, wire angles,
etc.).  The up-casts used for final S4I CTD data are indicated in Appendix C.

There is an inherent problem in the internal digitizing circuitry of the
NBIS Mark III CTD when the sign bit for temperature flips.  Raw temperature
can shift 1-2 millidegrees as values cross between positive and negative, a
problem usually avoided by offsetting the raw PRT readings by ~1.5 deg.C.
The conductivity channel also can shift by 0.001-0.002 mS/cm as raw data
values change between 32768/32767, where all the bits flip at once.  This
is typically not a problem in shallow to intermediate depths because such a
small shift becomes negligible in higher gradient areas.

There were a number of casts colder than -1.5 deg.C, where raw temperature
values crossed the 0 deg.C threshold.  All transitions falling in lower-
gradient areas were shallower than 480 db and showed no density inversions.  All 
raw conductivity values were lower than 32768 and unaffected by this problem.

Appendix C contains a table of CTD casts requiring special attention.  S4I
CTD-related comments, problems and solutions are documented in detail.


7.  CTD Laboratory Calibration Procedures

Pre-cruise laboratory calibrations of CTD pressure and temperature sensors
were used to generate tables of corrections applied by the CTD data
acquisition and processing software at sea.  These laboratory calibrations
were also performed post-cruise.

Pressure and temperature calibrations were performed on CTD #3 at the ODF
Calibration Facility in La Jolla.  Pre-cruise calibrations were done in
March 1996, and post-cruise calibrations were done in July 1996.

The CTD pressure transducer was calibrated in a temperature-controlled
water bath to a Ruska Model 2400 Piston Gage pressure reference.
Calibration data were measured pre-/post-cruise at -1.89/-1.10 deg.C to a
maximum loading pressure of 6080 db, and 10.08/30.34 deg.C to 1190 db.  An
additional pressure calibration was done post-cruise at 4.07 deg.C to 6080
db.  Figures 7.0 and 7.1 summarize the CTD #3 laboratory pressure
calibrations performed in March and July 1996.


Figure 7.0  Pressure calibration for ODF CTD #3, March 1996.
Figure 7.1  Pressure calibration for ODF CTD #3, July 1996.


Additionally, dynamic thermal-response step tests were conducted on the
pressure transducer to calibrate dynamic thermal effects.  These results
were combined with the static temperature calibrations to optimally correct
the CTD pressure.

CTD PRT temperatures were calibrated to an NBIS ATB-1250 resistance bridge
and Rosemount standard PRT in a temperature-controlled bath.  The primary
and secondary CTD temperatures were offset by ~1.5 and ~2 deg.C to avoid
the 0-point discontinuity inherent in the internal digitizing circuitry.
Standard and CTD temperatures were measured pre-cruise for the primary PRT
at 7 different bath temperatures between -1.9 and 10.1 deg.C.  The primary
and secondary PRT #FSI-1320T were both calibrated post-cruise at more than
a dozen bath temperatures between -1.9 and 30.3 deg.C.  Figures 7.2 and 7.3
summarize the laboratory calibrations performed on the CTD #3 primary PRT
during March and July 1996.  Figure 7.4 shows the laboratory calibration
performed on the CTD #3 secondary PRT (FSI-1320T only) during July 1996.


Figure 7.2  Primary PRT Temperature Calibration for ODF CTD #3, March 1996.
Figure 7.3  Primary PRT Temperature Calibration for ODF CTD #3, July 1996.
Figure 7.4  Secondary PRT (FSI-1320T) Temperature Calibration for ODF CTD #3, 
            July 1996.


These laboratory temperature calibrations were referenced to an ITS-90
standard.  Temperatures were converted to the IPTS-68 standard during
processing in order to calculate other parameters, including salinity and
density, which are currently defined in terms of that standard only.  Final
calibrated CTD temperatures are reported using the ITS-90 standard.


8.  CTD Calibration Procedures

ODF CTD #3 had recently been acquired by ODF and did not have an extensive
calibration history.

A redundant PRT sensor was used as a temperature calibration check while at
sea.  CTD conductivity and dissolved O2 were calibrated to in situ check
samples collected during each rosette cast.

Final pressure, temperature, conductivity and oxygen corrections were
determined during post-cruise processing.


8.1.  CTD #3 Pressure

There was a pre- to post-cruise shift in the loading curves (increasing
pressure) of less than -0.5 db in the top 2000 db, gradually shifting to a
maximum +0.5 db at the maximum pressure in the cold-bath laboratory
calibrations for pressure.  The unloading curves were similar in the top
1000 db, and shifted a fairly consistent +0.5 db in the post-cruise.

The intermediate-temperature (10/4 deg.C pre-/post-cruise) pressure
calibrations were less easily compared, since they differed by 6 deg.C and
were done to different maximum pressures.  For easier comparison, the deep
extrapolation of the pre-cruise 10 deg.C calibration was used.  The loading
curves were within +/-0.5 db of each other in the top 3500 db, with the
post-cruise shifting by a maximum -0.5 db at 6080 db.  The unloading curves
crossed around 4500 db, with the post-cruise calibration showing a maximum
+0.8 db at 1100 db, then closing in again to within +/-0.2 db near the
surface.

The 4 deg.C calibration (post-cruise) would typically be twice as close as
the 10 deg.C calibration (pre-cruise) to the -1 deg.C calibrations, if
there were no shift in CTD pressure.  However, the difference between the
cold and intermediate calibrations at maximum pressure became twice as
large instead (0.6 db in 12 deg.C pre-cruise vs 1.3 db in 5 deg.C post-
cruise).  The differences between the calibrations were still less than 1
db at any calibration temperature or pressure, a relatively insignificant
amount.  A test comparing the results of using one calibration or the other
showed less than +/-0.3 db differences in maximum pressures for each cast
deeper than 1500 db, and 0.3 to 0.9 db differences in casts shallower than
1500 db.  The pre-cruise calibration data, plus the dynamic thermal-
response correction, were applied to S4I CTD #3 pressure data to generate
final pressures.

Down-cast surface pressures were automatically adjusted to 0 db as the CTD
entered the water; any difference between this value and the calibration
value was automatically adjusted during the top 50 decibars.  Residual
pressure offsets at the end of each up-cast (the difference between the
last corrected pressure in-water and 0 db) averaged 0.9 db, indicating no
significant problems with the final pressure corrections.

The entire pre- to post-cruise laboratory calibration shift for the
pressure sensor on CTD #3 was less than one-half the magnitude of the WOCE
accuracy specification of 3 db.  Final adjusted S4I CTD pressures should be
well within the desired standards.

An FSI-OPM/pressure module (1326P) was substituted for the secondary PRT
during stations 103 through 106 as a test of the OPM.  These secondary
pressure data were neither processed nor calibrated.


8.2.  CTD #3 Temperature

Three different FSI-OTM/PRT sensors (S/N 1320T, 1322T, 1321T) were deployed
as a second temperature channel (PRT2) and compared with the primary PRTchannel 
(PRT1) on all casts except stations 103-106 to monitor for drift. The response 
times of the primary and secondary PRT sensors were matched, then preliminary 
corrected temperatures were compared for a series of standard depths from each 
CTD down-cast.

OTM-1320T was used for stations 1-61 and 107-108, OTM-1322T was used for
stations 62-100, and OTM-1321T was used for stations 101-102 only.  Since
no OTM was attached during the pre-cruise calibration, a simple offset of
-2.0 was used to correct PRT2 for comparison to PRT1 data, a correction
within 0.0025 deg.C of calibration checks of all 3 OTMs in November 1996.
The differences between the CTD #3 primary PRT and all 3 OTM sensors
remained a fairly stable +/-0.0005 deg.C for pressures deeper than 1500 db.
A stable conductivity correction also indicated no shift in the primary PRT.

Figure 8.2.0 summarizes the comparison between the primary and secondary
PRT temperatures.


Figure 8.2.0  S4I comparison of CTD #3 primary vs. secondary PRT temperatures,
              pressure > 1500 db (no Sta.031).
 
 
The primary temperature sensor laboratory calibrations indicated a -0.0015
deg.C shift at -1.5 to 6 deg.C, with no slope change, from pre- to post-
cruise.  Figure 8.2.1 shows the pre-/post-cruise PRT1 calibrations plotted
together, using only uncorrected PRT1 values above 0 deg.C.


Figure 8.2.1  WOCE96-S4I Primary temperature (PRT1) correction for ODF CTD #3,
              March + July'96 calibs, rawPRT1 > 0 deg.C only.
 
 
The post-cruise PRT1 calibration measured more temperature points and was
more consistent, so it was offset by +0.00075 deg.C (half of the pre- to
post-cruise change) and applied to S4I temperature data.  Figure 8.2.2
shows the offset post-cruise temperature calibration used to correct CTD #3
PRT1 data.


Figure 8.2.2  WOCE96-S4I Primary temperature (PRT1) correction for ODF CTD #3,
              July'96 calib. +0.00075 deg.C.
 
 
Two casts (stations 30 and 31) had problems with PRT1 readings, caused by a
flooded sensor turret; the problem was repaired before station 32.  It was
necessary to use PRT2 for the primary temperature data on these two casts,
despite the expected noisier salinity caused by the distance between PRT2
and the conductivity sensor.  The post-cruise secondary temperature sensor
laboratory calibration showed a fairly constant -1.9997 deg.C offset
between -1.1 and 9 deg.C, covering the full range of temperatures seen on
these two casts.  This offset was applied to correct the PRT2 temperature
data for stations 30 and 31.  Figure 8.2.3 shows the post-cruise
temperature calibration data used to correct CTD #3 PRT2 data.


Figure 8.2.3  WOCE96-S4I Secondary temperature (PRT2) correction for ODF CTD #3,
              July'96 calib., rawPRT2 from 0.5 to 10.5 deg.C only.
 
 
The pre- to post-cruise laboratory calibration shift for the primary
temperature sensor on CTD #3 was less than the magnitude of the WOCE
accuracy standard of 0.002 deg.C for the temperature range of the S4I line.
Since the difference between the two calibrations was essentially split and
applied to the data, S4I CTD temperatures should be within the WOCE
accuracy specifications.  PRT2 data compared well to PRT1 data throughout
the cruise, and should also be within the same accuracy range as PRT1.

The exception to these accuracy figures would be where uncorrected CTD
temperatures cross between positive and negative values: the discontinuity
described in the "CTD Data Processing" section may offset colder data.
This error may be as much as +0.0025 deg.C for corrected CTD temperatures
below ~-1.49 deg.C, an amount apparent in the figures for PRT1 Temperature
Calibrations seen in the previous section.  Fortunately, all such
temperatures on S4I are shallower than 480 db and fall in areas where the
temperature gradient is larger than the error, so it is not readily
detectable.


8.3.  CTD #3 Conductivity

The corrected CTD rosette trip pressure and temperature were used with the
bottle salinity to calculate a bottle conductivity.  Differences between
the bottle and CTD conductivities were then used to derive a conductivity
correction.  This correction is normally linear for the 3-cm conductivity
cell used in the Mark III CTD, but CTD #3 sensors required pressure-
dependent conductivity corrections as well.

Three different CTD conductivity sensors were used during S4I; all three
sensors were essentially new at the start of S4I.

  o  #E55 was used on stations 1-31.  It was replaced because the sensor
     turret leaked during stations 30-31.

  o  #P42 was used on stations 32-38.  It was replaced because of nonlinear
     sensitivity and lack of stability.

  o  #E55 was again used on stations 39-61.  This sensor became extremely
     noisy during stations 56-58.  The sensor was cleaned with RBS prior to
     station 59, which caused a shift in the offset while significantly
     reducing the noise level.  The sensor was replaced because of
     nonlinear sensitivity and lack of stability.

  o  #O17 was used on stations 62-108.  It was fairly stable, with a small
     shift after the 6.5-day break in station work to deliver supplies to
     Mirnyy.

Conductivity differences above and below the thermocline were fit to CTD
conductivity for each conductivity sensor to determine conductivity slopes.
Stations 1-31, 39-55 and 56-61 were treated separately for sensor #E55, and
stations 62-72 and 73-108 were grouped separately for sensor #O17.  Figures
8.3.0.0-8.3.0.5 show the data used to determine preliminary conductivity
slopes.


Figure 8.3.0.0  CTD #3 prelim. conductivity slopes for WOCE96-S4I, stations
                1-31 (C-sensor #E55).
Figure 8.3.0.1  CTD #3 prelim. conductivity slopes for WOCE96-S4I, stations
                32-38 (C-sensor #P42).
Figure 8.3.0.2  CTD #3 prelim. conductivity slopes for WOCE96-S4I, stations
                39-55 (C-sensor #E55).
Figure 8.3.0.3  CTD #3 prelim. conductivity slopes for WOCE96-S4I, stations
                56-61 (C-sensor #E55).
Figure 8.3.0.4  CTD #3 prelim. conductivity slopes for WOCE96-S4I, stations
                62-72 (C-sensor #O17).
Figure 8.3.0.5  CTD #3 prelim. conductivity slopes for WOCE96-S4I, stations
                73-108 (C-sensor #O17).


These preliminary conductivity differences were fit to conductivity, with
outlying values (4,2 standard deviations) rejected.  Shallower stations
were omitted from all groups; only stations 56-58 were used to determine
slopes for stations 56-61 because of the offset caused by cleaning the
sensor prior to station 59.  Conductivity slopes were calculated from the
first-order fits.  The slopes calculated for stations 1-31 and 39-55 were
averaged, as were the slopes for stations 62-72 and 73-108.  Preliminary
slopes were then applied to each S4I cast.

Once the conductivity slopes were applied, residual CTD conductivity offset
values were calculated for each cast using bottle conductivities deeper
than 1400 db for stations 1-31, 39-55 and 62-108.  More restricted pressure
ranges were used to determine preliminary offsets for casts with unstable
conductivity sensors, while pressure-dependent conductivity corrections
were pending: only 0-70 db differences were used for stations 32-38, and
2300-2800 db for stations 56-61.  Figure 8.3.1 illustrates the S4I
preliminary conductivity offset residual values.

Figure 8.3.1 S4I CTD #3 preliminary conductivity offsets by station number.
Casts were grouped together based on drift and/or known CTD conductivity
shifts or problems to determine average offsets.  This also smoothed the
effect of any cast-to-cast bottle salinity variation, typically on the
order of +/-0.001 PSU.  Some casts were omitted from the fits because there
were no bottle differences within the specified pressure ranges used, or
because of known CTD shifts relative to nearby casts.  Smoothed offsets
were applied to each cast except stations 32-38 and 56-61, which had
individual offsets applied because of sensor instabilities.  Some offsets
were then manually adjusted to account for discontinuous shifts in the
conductivity transducer response or bottle salinities, or to maintain deep
theta-salinity consistency from cast to cast.


After applying preliminary conductivity slopes and offsets to each cast,
residual CTD conductivity differences above and below the thermocline were
fit to CTD pressure for each sensor.  Stations 1-31 + 39-55 conductivity
differences varied +/-0.002 mS/cm and warranted a second-order correction
as a function of pressure.  Stations 62-108 needed a linear correction as a
function of pressure to pull in the 0.001 mS/cm differences at intermediate
pressures.  Stations 32-38 and 56-61 required individual second-order
corrections (linear for shallow station 35) as a function of pressure to
pull in much larger residual differences.  Figures 8.3.2.0-8.3.2.3 show the
residual conductivity differences used for determining these corrections.


Figure 8.3.2.0  CTD #3 residual conductivity vs. pressure for WOCE96-S4I,
                stas 1-31 + 39-55 (C-sensor #E55).
Figure 8.3.2.1  CTD #3 residual conductivity vs. pressure for WOCE96-S4I,
                stas 32-38 (C-sensor #P42).
Figure 8.3.2.2  CTD #3 residual conductivity vs. pressure for WOCE96-S4I,
                stas 56-61 (C-sensor #E55).
Figure 8.3.2.3  CTD #3 residual conductivity vs. pressure for WOCE96-S4I,
                stas 62-108 (C-sensor #O17).
 
 
After applying the pressure-dependent corrections to conductivity,
conductivity slopes were re-examined for any leftover dependence on
conductivity.  Two groups needed minor adjustments to conductivity slopes
as a function of conductivity.  Figures 8.3.3.0 and 8.3.3.1 show the
residual corrections calculated for stations 55-61 and stations 62-108.


Figure 8.3.3.0  CTD #3 adjustments to conductivity slopes for WOCE96-S4I,
                stas 55-61 (C-sensor #E55).
 
Figure 8.3.3.1  CTD #3 adjustments to conductivity slopes for WOCE96-S4I,
                stas 62-108 (C-sensor #O17).


The final S4I pressure-dependent coefficients and conductivity-dependent
slopes are summarized in Figures 8.3.4 and 8.3.5.  Figure 8.3.6 summarizes
the final conductivity offsets (combined conductivity- and pressure-
dependent corrections) by station number.


Figure 8.3.4  S4I CTD #3 pressure-dependent correction coefficients by
              station number.
Figure 8.3.5  S4I CTD #3 conductivity-dependent slope corrections by station 
              number.
Figure 8.3.6  S4I CTD #3 combined conductivity offsets by station number.


S4I temperature and conductivity correction coefficients are also tabulated
in Appendix A.


Summary of Residual Salinity Differences

Figures 8.3.7, 8.3.8, 8.3.9 and 8.3.10 summarize the S4I residual
differences between bottle and CTD salinities after applying the
conductivity corrections.  Only CTD and bottle salinities with final
quality code 2 (acceptable) were used to generate these figures and
statistics.  Residual differences exceeding +/- 0.025 PSU are included in
the calculations for averages and standard deviations, even though they arenot plotted.


Figure 8.3.7  S4I Salinity residual differences vs pressure (after correction).
Figure 8.3.8  S4I Salinity residual differences vs station # (after correction).
Figure 8.3.9  S4I Deep salinity residual differences vs station # (after 
              correction). 
 

The CTD conductivity calibration represents a best estimate of the
conductivity field throughout the water column.  3-sigma from the mean
residual in Figures 8.3.8 and 8.3.9, or +/- 0.0059 PSU for all salinities
and +/- 0.0015 PSU for deep salinities, represents the limit of
repeatability of the bottle salinities (Autosal, rosette, operators and
samplers).  This limit agrees with station overlays of deep theta-salinity.
Within most casts (a single salinometer run), the precision of bottle
salinities and CTD salinities appears to be better than 0.001 PSU.

Final calibrated CTD data from WOCE96-S4I and various cruises were compared
at their closest stations.  Non-S4I WOCE data were extracted from
http://whpo.ucsd.edu in March 2003.  A table of the comparisons follows:


Table 8.3.10 S4I Compared To Historical Data

S4I     |Crs.ID/         |Crs.   |IAPSO SSW |Distance  |Avg. Salinity Diffc. (Crs-S4I)       
Sta.No. |Sta.No.         |Date   |Batch No. |Apart(nm) |(PSU at Deepest 1 deg.C Theta)       
--------|----------------|-------|----------|----------|-------------------------------------
1       |WOCE-S4A/20     |Mar.96 |P-127     |68        |0 to +0.001 (vs. S4A btls -          
        |(06AQANTXIII_4) |       |          |          |CTD salinity quality-coded 4)        
--------|----------------|-------|----------|----------|-------------------------------------
63,64   |WOCE-I8S/76     |Dec.94 |P-124     |13,27     |+0.001                               
92      |WOCE-I9S/92     |Jan.95 |P-124     |9         |+0.001                               
        |(316N145_5)     |       |          |          |                                     
--------|----------------|-------|----------|----------|-------------------------------------
105     |WOCE-S3+S4/17   |Jan.95 |P-123     |9         |+0.003 to +0.0035                    
106     |WOCE-S3+S4/18   |Jan.95 |P-123     |12        |+0.0005 to +0.002                    
107     |WOCE-S3+S4/3-4  |Dec.94 |P-123     |14        |+0.006 to +0.007 *                   
108     |WOCE-S3+S4/2    |Dec.94 |P-123     |0.5       |+0.001 to +0.002                     
108     |WOCE-S3+S4/19   |Jan.95 |P-123     |0.1       | 0 (0.5+ deg.C Theta) to +0.004 (deep)
        |(09AR9404_1)    |       |          |          |                                     
--------|----------------|-------|----------|----------|-------------------------------------
11      |WOCE-S4/12345   |Feb.93 |P-120     |46        |-0.002 (below -0.04 deg.C Theta)     
        |                |       |          |          |-0.0005 (-0.04 to 0.45 deg.C Theta)  
86      |WOCE-S4/12351   |Feb.93 |P-120     |21        |-0.004 (S4I 300m shallower than S4)  
        |(74DI200_1)     |       |          |          |                                     
--------|----------------|-------|----------|----------|-------------------------------------
48,49   |GEOSECS/430     |Feb.78 |P-61      |201,188   |+0.004/+0.003                        
85      |GEOSECS/431     |Feb.78 |P-61      |76        |+/-0.002 above 0.2 deg.C Theta       
        |                |       |          |          |(incomparable deeper)                
88,89   |GEOSECS/430     |Feb.78 |P-61      |180,178   |+0.002                               

 * these S3+S4 casts were +0.003 to +0.0045 PSU compared to nearby casts on the   
   same cruise  


IAPSO Standard Seawater batch corrections are similar for S4I (P-125) and
most of the standards used for the other cruises listed in the chart: at
most, -0.0004 PSU in salinity.  The P-123/P-125 batch difference may
account for up to a +0.001 PSU difference between S3+S4/S4I salinity data
[Culk98].  S4A stations 3-4 are probably not good for comparison, since
they are offset from nearby casts on the same cruise.  S4I stations 105-108
all agree within +/- 0.0005 PSU.  IAPSO batch corrections would bring the
GEOSECS data about 0.001 PSU closer to S4I [Mant87] [Culk98].


8.4.  CTD Dissolved Oxygen

SensorMedics oxygen sensors have a finite shelf life, so new sensors are
usually employed at the start of a cruise.  A single, new O2 sensor was
used throughout S4I.  The pressure-related response problems observed
during WOCE95-I10 were not apparent during this leg.  The oxygen sensor
from this cruise was used again 8 months later, during WOCE97-ICM3 at 20S.

The extremely cold temperatures during S4I apparently caused problems with
the CTD O2 fits, since no fitting problems occurred for this same sensor on
ICM3.  Either the surface mixed layer fit the bottle oxygen data, causing 
arelatively shapeless deeper fit; or the deeper data fit the bottle-defined
structure well at the expense of surface fits.  Since freezing problems at
the surface were observed with temperature and conductivity sensors, it is
likely that the oxygen sensor was also affected.  Most surface oxygen fits
were sacrificed in order to define sub-thermocline CTD O2 structure; these
poorly fit areas are documented in Appendix C, and the data are quality-
coded 3 or 4.

There are a number of problems with the response characteristics of the
SensorMedics O2 sensor used in the NBIS Mark III CTD, the major ones being
a secondary thermal response and a sensitivity to profiling velocity.
Stopping the rosette for as little as half a minute, or slowing down for a
bottom approach, can cause shifts in the CTD O2 profile as oxygen becomes
depleted in water near the sensor.  Such shifts could usually be corrected
by offsetting the raw oxygen data from the stop or slow-down area until
some time after the sensor has been moving again, occasionally until the
bottom of the cast.  All offset sections, winch stops or slow-downs that
affected CTD oxygen data are documented in Appendix C.

Because of these same stop/slow-down problems, up-cast CTD O2 data cannot
be optimally calibrated to O2 check samples.  Instead, down-cast CTD O2
data are derived by matching the up-cast rosette trips along isopycnal
surfaces.  When down-casts were deemed to be unusable (see Appendix C), up-
cast CTD O2 data were processed despite the signal drop-offs typically seen
at bottle stops.  The differences between CTD O2 data modeled from these
derived values and check samples are then minimized using a non-linear
least-squares fitting procedure.

Figures 8.4.0 and 8.4.1 show the residual differences between the corrected
CTD O2 and the bottle O2 (ml/l) for each station.  Only CTD and bottle
oxygens with final quality code 2 (acceptable) were used to generate these
figures and statistics.  Residual differences exceeding +/- 0.5 ml/l are
included in the calculations for averages and standard deviations, even
though they are not plotted.


Figure 8.4.0  S4I O2 residual differences vs station # (after correction).
Figure 8.4.1  S4I Deep O2 residual differences vs station # (after correction).
 
 
The standard deviations of 0.044 ml/l for all oxygens and 0.015 ml/l for
deep oxygens are only intended as indicators of how well the up-cast bottle
and pressure-series (mostly down-cast) CTD O2 values match up.  ODF makes
no claims regarding the precision or accuracy of CTD dissolved O2 data.

The general form of the ODF O2 conversion equation follows Brown and
Morrison [Brow78] and Millard [Mill82], [Owen85].  ODF does not use a
digitized O2 sensor temperature to model the secondary thermal response but
instead models membrane and sensor temperatures by low-pass filtering the
PRT temperature.  In situ pressure and temperature are filtered to match
the sensor response.  Time-constants for the pressure response Taup, and
two temperature responses TauTs and TauTf are fitting parameters.  The Oc
gradient, dOc/dt, is approximated by low-pass filtering 1st-order Oc
differences.  This gradient term attempts to correct for reduction of
species other than O2 at the cathode.  The time-constant for this filter,
Tauog, is a fitting parameter.  Oxygen partial-pressure is then calculated:

     Opp=[c1*Oc+c2]*fsat(S,T,P)*e**(c3*Pl+c4*Tf+c5*Ts+c6*dOc/dt)    (8.4.0)

where:

  Opp         = Dissolved O2 partial-pressure in atmospheres (atm);
  Oc          = Sensor current (uamps);
  fsat(S,T,P) = O2 saturation partial-pressure at S,T,P (atm);
  S           = Salinity at O2 response-time (PSUs);
  T           = Temperature at O2 response-time (deg.C);
  P           = Pressure at O2 response-time (decibars);
  Pl          = Low-pass filtered pressure (decibars);
  Tf          = Fast low-pass filtered temperature (deg.C);
  Ts          = Slow low-pass filtered temperature (deg.C);
  dOc/dt      = Sensor current gradient (uamps/secs).


S4I CTD O2 correction coefficients (c1 through c6) are tabulated in
Appendix B.


9.  Bottle Sampling

At the end of each rosette deployment, water samples were drawn from the
bottles in the following order:

  o  CFCs;
  o  3He;
  o  O2;
  o  PCO2;
  o  Total CO2;
  o  AMS 14C;
  o  Nutrients;
  o  Salinity;
  o  18O/16O;
  o  Tritium;
  o  Alkalinity.


Since some properties were not sampled on every cast, the actual sample-
drawing sequence was modified as necessary.

The correspondence between individual sample containers and the rosette
bottle from which the sample was drawn was recorded on the sample log for
the cast.  This log also included any comments or anomalous conditions
noted about the rosette and bottles.  One member of the sampling team was
designated the sample cop, whose sole responsibility was to maintain this
log and insure that sampling progressed in the proper drawing order.

Normal sampling practice included opening the drain valve and then the air
vent on the bottle, indicating an air leak if water escaped.  This
observation together with other diagnostic comments (e.g., "lanyard caught
in lid", "valve left open") that might later prove useful in determining
sample integrity were routinely noted on the sample log.

Drawing oxygen samples also involved taking the sample draw temperature
from the bottle.  The temperature was noted on the sample log and was
sometimes useful in determining leaking or mis-tripped bottles.

Once individual samples had been drawn and properly prepared, they were
distributed to their respective laboratories for analysis.  Oxygen,
nutrients and salinity analyses were performed on computer-assisted (PC)
analytical equipment networked to Sun SPARCstations for centralized data
analysis.  The analysts for each specific property were responsible for
insuring that their results were updated into the cruise database.


10.  Bottle Data Processing

Bottle data processing began with sample drawing, and continued until the
data were considered to be final.  One of the most important pieces of
information, the sample log sheet, was filled out during the drawing of the
many different samples.  It was useful both as a sample inventory and as a
guide for the technicians in carrying out their analyses.  Any problems
observed with the rosette before or during the sample drawing were noted on
this form, including indications of bottle leaks, out-of-order drawing,
etc.  Oxygen draw temperatures recorded on this form were at times the
first indicator of rosette bottle-tripping problems. Additional clues
regarding bottle tripping or leak problems were found by individual
analysts as the samples were analyzed and the resulting data were processed
and checked.

The next stage of processing was accomplished after the individual
parameter files were merged into a common station file, along with CTD-
derived parameters (pressure, temperature, conductivity, etc.).  The
rosette cast and bottle numbers were the primary identification for all
ODF-analyzed samples taken from the bottle, and were used to merge the
analytical results with the CTD data associated with the bottle.  At this
stage, bottle tripping problems were usually resolved, sometimes resulting
in changes to the pressure, temperature and other CTD properties associated
with the bottle.  All CTD information from each bottle trip (confirmed or
not) was retained in a file, so resolving bottle tripping problems
consisted of correlating CTD trip data with the rosette bottles.
Diagnostic comments from the sample log, and notes from analysts and/or
bottle data processors were entered into a computer file associated with
each station (the "quality" file) as part of the quality control procedure.
Sample data from bottles suspected of leaking were checked to see if the
properties were consistent with the profile for the cast, with adjacent
stations, and, where applicable, with the CTD data.  Various property-
property plots and vertical sections were examined for both consistency
within a cast and consistency with adjacent stations by data processors,
who advised analysts of possible errors or irregularities.  The analysts
reviewed and sometimes revised their data as additional calibration or
diagnostic results became available.

Based on the outcome of investigations of the various comments in the
quality files, WHP water sample codes were selected to indicate the
reliability of the individual parameters affected by the comments.  WHP
bottle codes were assigned where evidence showed the entire bottle was
affected, as in the case of a leak, or a bottle trip at other than the
intended depth.

WHP water bottle quality codes were assigned as defined in the WOCE
Operations Manual [Joyc94] with the following additional interpretations:

   2 | No problems noted.
   3 | Leaking.  An air leak large enough to produce an
     | observable effect on a sample is identified by a code of
     | 3 on the bottle and a code of 4 on the oxygen.  (Small
     | air leaks may have no observable effect, or may only
     | affect gas samples.)
   4 | Did not trip correctly.  Bottles tripped at other than
     | the intended depth were assigned a code of 4.  There may
     | be no problems with the associated water sample data.
   5 | Not reported.  No water sample data reported.  This is a
     | representative level derived from the CTD data for
     | reporting purposes.  The sample number should be in the
     | range of 80-99.
   9 | The samples were not drawn from this bottle.


WHP water sample quality flags were assigned using the following criteria:

   1 | The sample for this measurement was drawn from the water
     | bottle, but the results of the analysis were not (yet)
     | received.
   2 | Acceptable measurement.
   3 | Questionable measurement.  The data did not fit the
     | station profile or adjacent station comparisons (or
     | possibly CTD data comparisons).  No notes from the
     | analyst indicated a problem.  The data could be
     | acceptable, but are open to interpretation.
   4 | Bad measurement.  The data did not fit the station
     | profile, adjacent stations or CTD data.  There were
     | analytical notes indicating a problem, but data values
     | were reported.  Sampling and analytical errors were also
     | coded as 4.
   5 | Not reported.  There should always be a reason
     | associated with a code of 5, usually that the sample was
     | lost, contaminated or rendered unusable.
   9 | The sample for this measurement was not drawn.


WHP water sample quality flags were assigned to the CTDSAL (CTD salinity)
parameter as follows:

   2 | Acceptable measurement.
   3 | Questionable measurement.  The data did not fit the
     | bottle data, or there was a CTD conductivity calibration
     | shift during the up-cast.
   4 | Bad measurement.  The CTD up-cast data were determined
     | to be unusable for calculating a salinity.
   7 | Despiked.  The CTD data have been filtered to eliminate
     | a spike or offset.

WHP water sample quality flags were assigned to the CTDO (CTD O2) parameter
as follows:

   1 | Not calibrated.  Data are uncalibrated.
   2 | Acceptable measurement.
   3 | Questionable measurement.
   4 | Bad measurement.  The CTD data were determined to be
     | unusable for calculating a dissolved oxygen
     | concentration.
   5 | Not reported.  The CTD data could not be reported,
     | typically when CTD salinity is coded 3 or 4.
   7 | Despiked.  The CTD data have been filtered to eliminate
     | a spike or offset.
   9 | Not sampled.  No operational CTD O2 sensor was present
     | on this cast.


Note that CTDO values were derived from the down-cast pressure-series CTD
data, except for 18 stations where up-casts were processed because of
conductivity problems on the down-casts.  CTD data were matched to the up-
cast bottle data along isopycnal surfaces.  If the CTD salinity is
footnoted as bad or questionable, the CTD O2 is not reported.

Table 10.0 shows the number of samples drawn and the number of times each
WHP sample quality flag was assigned for each basic hydrographic property:


Table 10.0  Frequency of WHP quality flag assignments for S4I.

                      Rosette Samples Stations 001-108                      
----------------------------------------------------------------------------
            Reported                     WHP Quality Codes                  
             Levels        1       2       3       4       5       7       9
----------||---------|------------------------------------------------------
Bottle    ||  3655   |     0    3542       1     108       0       0       4
CTD Salt  ||  3655   |     0    3493       0      36       0     126       0
CTD Oxy   ||  3619   |     0    2909     111     599      36       0       0
Salinity  ||  3604   |     0    3521      24      59       9       0      42
Oxygen    ||  3630   |     0    3568      33      29       7       0      18
Silicate  ||  3640   |     0    3638       1       1       0       0      15
Nitrate   ||  3640   |     0    3639       0       1       0       0      15
Nitrite   ||  3640   |     0    3639       0       1       0       0      15
Phosphate ||  3640   |     0    3602       3      35       0       0      15


Additionally, all WHP water bottle/sample quality code comments are
presented in Appendix D.


11.  Pressure and Temperatures

All pressures and temperatures for the bottle data tabulations on the
rosette casts were obtained by averaging CTD data for a brief interval at
the time the bottle was closed on the rosette, then correcting the data
based on CTD laboratory calibrations.

The temperatures are reported using the International Temperature Scale of
1990.


12.  Salinity Analysis

Equipment and Techniques

Two Guildline Autosal Model 8400A salinometers were available for measuring
salinities.  The salinometers were modified by ODF and contained interfaces
for computer-aided measurement.  Autosal #57-396 was a backup unit but was
not used on this expedition.  Autosal #55-654 was used to measure salinity
on all stations.  Its water bath temperature was set and maintained at 24
deg.C for all runs except stations 32-39, where the bath temperature was
set at 21 deg.C.

The salinity analyses were performed when samples had equilibrated to
laboratory temperature, within 7-28 hours after collection.  The
salinometer was standardized for each group of analyses (typically one
cast, usually 36 samples) using two fresh vials of standard seawater per
group.  A computer (PC) prompted the analyst for control functions such as
changing sample, flushing, or switching to "read" mode.  At the correct
time, the computer acquired conductivity ratio measurements, and logged
results.  The sample conductivity was redetermined until readings met
software criteria for consistency.  Measurements were then averaged for a
final result.

Unstable readings were encountered during analysis of the first 5 samples
from station 42.  The Autosal flow cell was cleaned, and sample analysis
was resumed ~10 hours later without further problems.


Sampling and Data Processing

Salinity samples were drawn into 200 ml Kimax high-alumina borosilicate
bottles, which were rinsed three times with sample prior to filling.  The
bottles were sealed with custom-made plastic insert thimbles and Nalgene
screw caps.  This assembly provides very low container dissolution and
sample evaporation.  Prior to collecting each sample, inserts were
inspected for proper fit and loose inserts were replaced to insure an
airtight seal.  The draw time and equilibration time were logged for all
casts.  Laboratory temperatures were logged at the beginning and end of
each run.

PSS-78 salinity [UNES81] was calculated for each sample from the measured
conductivity ratios.  The difference (if any) between the initial vial of
standard water and one run at the end as an unknown was applied linearly to
the data to account for any drift.  The data were added to the cruise
database.  3604 salinity measurements were made and 233 vials of standard
water were used.  The estimated accuracy of bottle salinities run at sea is
usually better than 0.002 PSU relative to the particular standard seawater
batch used.


Laboratory Temperature

The temperature stability in the salinometer laboratory was fair, ranging
from 18.7 to 25.8 deg.C and drifting an average of 0.5 deg.C during a run
of samples.  The laboratory temperature was between -4 and +2 deg.C of the
Autosal bath temperature during all sample runs.


Standards

IAPSO Standard Seawater (SSW) Batch P-125 was used to standardize the
salinometers.


13.  Oxygen Analysis

Equipment and Techniques

Dissolved oxygen analyses were performed with an ODF-designed automated
oxygen titrator using photometric end-point detection based on the
absorption of 365nm wavelength ultra-violet light.  The titration of the
samples and the data logging were controlled by PC software.  Thiosulfate
was dispensed by a Dosimat 665 buret driver fitted with a 1.0 ml buret.
ODF used a whole-bottle modified-Winkler titration following the technique
of Carpenter [Carp65] with modifications by Culberson et al. [Culb91], but
with higher concentrations of potassium iodate standard (approximately
0.012N) and thiosulfate solution (50 gm/l).  Carbon disulfide was added to
the thiosulfate as a preservative.  Standard solutions prepared from pre-
weighed potassium iodate crystals were run at the beginning of each session
of analyses, which typically included from 1 to 3 stations.  Nine standards
were made up during the cruise and compared to assure that the results were
reproducible, and to preclude the possibility of a weighing or dilution
error.  Reagent/distilled water blanks were determined, to account for
presence of oxidizing or reducing materials.


Sampling and Data Processing

Samples were collected for dissolved oxygen analyses soon after the rosette
sampler was brought on board, and after samples for CFCs and helium were
drawn.  Using a Tygon drawing tube, nominal 125ml volume-calibrated iodineflasks 
were rinsed twice with minimal agitation, then filled and allowed to
overflow for at least 3 flask volumes.  The sample draw temperature was
measured with a small platinum resistance thermometer embedded in the
drawing tube.  Reagents were added to fix the oxygen before stoppering.
The flasks were shaken twice to assure thorough dispersion of the
precipitate, once immediately after drawing, and then again after about 20
minutes.  The samples were analyzed within 1-9 hours of collection (18
hours for station 1 only), and then the data were merged into the cruise
database.

Thiosulfate normalities were calculated from each standardization and
corrected to 20 deg.C.  The 20 deg.C normalities and the blanks were
plotted versus time and were reviewed for possible problems.  New
thiosulfate normalities were recalculated after the blanks had been
smoothed as a function of time, if warranted.  These normalities were then
smoothed, and the oxygen data were recalculated.

Oxygens were converted from milliliters per liter to micromoles per
kilogram using the in situ temperature.  Sample temperatures were measured
at the time the samples were drawn from the rosette bottle.  These
temperatures were useful in indicating whether or not a bottle tripped
properly.

3630 oxygen measurements were made, with no major problems encountered
during the analyses.


Volumetric Calibration

Oxygen flask volumes were determined gravimetrically with degassed
deionized water to determine flask volumes at ODF's chemistry laboratory.
This is done once before using flasks for the first time and periodically
thereafter when a suspect bottle volume is detected.  The volumetric flasks
used in preparing standards were volume-calibrated by the same method, as
was the 10 ml Dosimat buret used to dispense standard iodate solution.


Standards

Potassium iodate standards, nominally 0.44 gram, were pre-weighed in ODF's
chemistry laboratory to +/-0.0001 grams.  The exact normality was
calculated at sea after the volumetric flask volume and dilution
temperature were known.  Potassium iodate was obtained from Johnson Matthey
Chemical Co.  and was reported by the supplier to be >99.4% pure.  All
other reagents were "reagent grade" and were tested for levels of oxidizing
and reducing impurities prior to use.


14.  Nutrient Analysis

Equipment and Techniques

Nutrient analyses (phosphate, silicate, nitrate and nitrite) were performed
on an ODF-modified 4-channel Technicon AutoAnalyzer II, generally within a
few hours after sample collection.  Occasionally samples were refrigerated
up to a maximum of 8 hours at 2-6 deg.C.  All samples were brought to room
temperature prior to analysis.

The methods used are described by Gordon et al. [Gord93].  The analog
outputs from each of the four channels were digitized and logged
automatically by computer (PC) at 2-second intervals.

Silicate was analyzed using the technique of Armstrong et al. [Arms67].  An
acidic solution of ammonium molybdate was added to a seawater sample to
produce silicomolybdic acid which was then reduced to silicomolybdous acid
(a blue compound) following the addition of stannous chloride.  Tartaric
acid was also added to impede PO4 color development.  The sample was passed
through a 15mm flowcell and the absorbance measured at 660nm.

A modification of the Armstrong et al. [Arms67] procedure was used for the
analysis of nitrate and nitrite.  For the nitrate analysis, the seawater
sample was passed through a cadmium reduction column where nitrate was
quantitatively reduced to nitrite.  Sulfanilamide was introduced to the
sample stream followed by N-(1-naphthyl)ethylenediamine dihydrochloride
which coupled to form a red azo dye.  The stream was then passed through a
15mm flowcell and the absorbance measured at 540nm.  The same technique was
employed for nitrite analysis, except the cadmium column was bypassed, and a 
50mm flowcell was used for measurement.

Phosphate was analyzed using a modification of the Bernhardt and Wilhelms
[Bern67] technique.  An acidic solution of ammonium molybdate was added to
the sample to produce phosphomolybdic acid, then reduced to
phosphomolybdous acid (a blue compound) following the addition of
dihydrazine sulfate.  The reaction product was heated to ~55 deg.C to
enhance color development, then passed through a 50mm flowcell and the
absorbance measured at 820nm.


Sampling and Data Processing

Nutrient samples were drawn into 45 ml polypropylene, screw-capped "oak-
ridge type" centrifuge tubes.  The tubes were cleaned with 10% HCl and
rinsed with sample twice before filling.  Standardizations were performed
at the beginning and end of each group of analyses (typically one cast,
usually 36 samples) with an intermediate concentration mixed nutrient
standard prepared prior to each run from a secondary standard in a low-
nutrient seawater matrix.  The secondary standards were prepared aboard
ship by dilution from primary standard solutions.  Dry standards were pre-
weighed at the laboratory at ODF, and transported to the vessel for
dilution to the primary standard.  Sets of 6-7 different standard
concentrations were analyzed periodically to determine any deviation from
linearity as a function of concentration for each nutrient analysis.  A
correction for non-linearity was applied to the final nutrient
concentrations when necessary.

After each group of samples was analyzed, the raw data file was processed
to produce another file of response factors, baseline values, and
absorbances.  Computer-produced absorbance readings were checked for
accuracy against values taken from a strip chart recording.  The data were
then added to the cruise database.

3640 nutrient samples were analyzed.  No major problems were encountered
with the measurements. The pump tubing was changed four times, and deep
seawater was run as a substandard check.  The temperature stability of the
laboratory used for the analyses was good, ranging from 20 to 24 deg.C.

Nutrients, reported in micromoles per kilogram, were converted from
micromoles per liter by dividing by sample density calculated at 1 atm
pressure (0 db), in situ salinity, and an assumed laboratory temperature of
25 deg.C.


Standards

The silicate primary standard (Na2SiF6) was obtained from Aesar and was
reported by the suppliers to be >98% pure.  The nitrite (NaNO2) primary
standard was obtained from GFS and was reported by the suppliers to be >97%
pure.  Primary standards for nitrate (KNO3) and phosphate (KH2PO4) were
obtained from Johnson Matthey Chemical Co., and the supplier reported
purities for each of 99.999%.



B.  Underway Measurements

B1. Navigation and Bathymetry

Navigation data were acquired from the ship's Ashtech GPS receiver via the 
network. They were logged automatically at one-minute intervals by one of the 
Sun Sparcstations. Underway bathymetry was logged manually from the ship's 12 
kHz Raytheon/EPC PDR at five-minute intervals (or when possible in the ice), 
then merged with the navigation data to provide a time-series of underway 
position, course, speed and bathymetry data. These data were used for all 
station positions, PDR depths, and for bathymetry on vertical sections (Carter, 
1980).  Depth data on the transit from Cape Town to station 1, and from station 
108 to Hobart were not logged. Data on station were not logged.


B2. Meteorological Observations

Five-minute average meteorological data are routinely recorded by the Palmer.  
Data recorded consist of time, position, air temperature, relative humidity, 
wet-bulb temperature, PSR, PIR, barometric pressure, and wind speed and 
direction.  Data were recorded continuously from Cape Town to Hobart.  
Significant data gaps (longer than 20 minutes, but less than 32 minutes in all 
cases) occurred on 19 and 27 May, and 1,2,4,7,20 and 24 June.


B3. Hull-mounted Acoustic Doppler Current Profiler
    (S. Rutz)

Ocean velocity observations were taken using a hull-mounted Acoustic Doppler 
Current Profiler (ADCP) system and GPS navigation data.  Data were recorded from 
May 3, 1995 to July 4, 1996 between Capetown, South Africa and Hobart, 
Australia, along the nominal latitude of 62°S from 20°E to 120°E with two 
transects across the Antarctic continental slope.  The purpose of the 
observations was to document the upper ocean horizontal velocity structure along 
the cruise track.  The observations provide absolute velocity estimates 
including the ageostrophic component of the flow.  Fig. 2  shows the cruise 
track and the near-surface currents measured by the ADCP.

The hull-mounted ADCP is part of the ship's equipment aboard the Palmer.  The 
ADCP is a 150 kHz unit manufactured by RD Instruments.  The instrument pings 
about once per second, and for most of the cruise the data were stored as 100-
second averages or ensembles.  The user-exit program, ue4, receives and stores 
the ADCP data along with both the P-code navigation data from a Trimble receiver 
and the positions from an Ashtech gps receiver.  The ship gyro provided heading 
information for vector averaging the ADCP data over the 100- second ensembles.  
The user-exit program calculates and stores the heading offset based on the 
difference between the heading determination from the Ashtech receiver and from 
the ship gyro.  The ADCP transducer is mounted in a glycol bath at a depth of 
about 7 meters below the sea surface. 

As setup parameters, a blanking interval of 16 meters, a vertical pulse length 
of 16 meters, a vertical bin size of 8 meters, and 60 bins were used.  A 300- 
second sampling interval was used at the beginning of the cruise and the 
interval was decreased to 100-seconds shortly after entering pack ice to 
increase the amount of usable data (cruising through ice severely limited the 
percent of good return pings).  100-seconds was the sampling interval for the 
remainder of the cruise.

Bottom tracking was activated during the shallow water transits near South 
Africa, Antarctica, and Tasmania.  For the processing of the ADCP data aboard 
ship, a rotation amplitude of 0.97, a rotation angle of -1.65 degrees (added to 
the gyro minus gps heading), and a time filter width of one hour were used. 
Final editing and calibration of the ADCP data has not yet been done.  For 
example, some spikes due to pinging off the CTD wire or rosette on station are 
still present in the data.

A set of preliminary plots was generated during the cruise.  The plots display 
velocity vectors averaged over several depth intervals, and over one hour in 
time.  The velocity was measured from a depth of 23 meters to a depth of about 
500 meters.

During the first few weeks of the cruise, the ADCP hung a half-dozen times for 
unknown reasons.  Several measures were taken to prevent this (e.g., the 
keyboard was locked) or to minimize its effect (e.g., a "watch dog" program was 
installed that would reboot the PC if it hung for more than about five minutes). 
These measures were mostly successful though the ADCP did hang one more time for 
unexplained reasons late in the cruise.

A Trimble P-code receiver was used for navigation.  The data from the receiver 
was stored once per second for the entire cruise.  The Ashtech receiver uses a 
four antennae array to measure position and attitude.  The heading estimate was 
used with the ship gyro to provide a heading correction for the ADCP ensembles. 
The Ashtech data was stored by the ADCP user-exit program along with the ADCP 
data.

The Ashtech receiver at times (especially after it had been reset) could not 
lock onto enough satellites to determine the ship's heading.  This was remedied 
by temporarily disabling certain satellites that were low on the horizon so that 
the Ashtech would not waste its time in a futile attempt to lock onto them.

Also, the ship gyro input to the ADCP hung about two dozen times during the 
cruise for intervals ranging from several minutes to hours.  The hangs were 
mostly due to the ship's data acquisition system (DAS) crashing.  An attempt to 
feed the ship gyro directly to the ADCP, bypassing the DAS, was unsuccessful and 
had some unintended consequences (i.e., the auto-pilot went berserk). 


B4. Atmospheric Chemistry
    (D. Chipman and M. Mensch)

Air samples for analysis were drawn from a single inlet located just forward of 
the ship's bridge through a continuous run of 3/8 inch diameter Dekoron tubing.  
A KNF Neuberger pump with a teflon-covered rubber diaphragm was use to 
pressurize the air for distribution to the CO2 analysis system in the Hydro Lab 
and the CFC analysis system in the Dry Lab. 

A vent line with a needle valve from a tee fitting at the CFC system provided 
backpressure for the line while allowing it to be continuously flushed with 
fresh atmospheric air.


CO2 Analysis

The LDEO underway pCO2 analysis system was used to determine the concentration 
of CO2 in dried atmospheric air.  At intervals of approximately one half hour, 
air from the atmospheric sampling line was allowed to flow through a 
countercurrent-flow permeation gas dryer and then through the cell of the Licor 
infrared gas analyzer for three minutes at a flow rate of 25-35 ml/min.  The 
sample flow was stopped for 20 seconds prior to reading the analyzer output, to 
allow time for the pressure to vent to the atmospheric value and for the sample 
to come to cell temperature.  Immediately following each atmospheric sample, the 
instrument was calibrated using a set of four compressed air-CO2 mixtures (which 
have CO2 concentrations traceable to the WMO scale of C.D. Keeling);  a second-
order polynomial response curve was fitted to the instrumental signals given by 
these gases and used to calculate the concentration of CO2 in the sample.
Atmospheric measurements were made whenever the pCO2 analysis system was 
operating, which was essentially continuously in open water and periodically 
(usually at stations only) when operating in the ice.  Because of the problem of 
contamination with stack gas when the relative wind was from behind the ship, 
only those analyses made when the ship's meteorological monitoring system 
indicated relative winds from ahead were considered valid and retained.


CFC Analysis

Marine air samples for CFC analysis were taken from the bow air line immediately 
in front of the T-fitting leading to the vent line.  The air was dried by 
flowing through magnesium perchlorate and then analyzed in exactly the same way 
standard gases were measured (Section C7).  Marine air was analyzed whenever the 
necessary time was available and the relative wind direction was from the bow.  
The results will provide information about the current atmospheric CFC levels 
and will allow the calculation of the CFC saturation levels in the surface 
water.


B5. Thermosalinograph and underway pCO2
    (D. Chipman)

The Palmer is fitted with two separate uncontaminated seawater lines- a 1-inch 
line of stainless steel and PVC, which supplies the thermosalinograph and other 
instruments in the Hydro Lab, and a 2-inch stainless steel line which provides 
water to the Aquarium Lab. 

Both have inlets located at a depth of approximately 6.7 meters, well aft of the 
bow to reduce the entrainment of air and ice during icebreaking operations. Due 
to a failure of the pump on the thermosalinograph line about one third of the 
way through the cruise, the thermosalinograph and underway pCO2 equilibrator 
were replumbed to be supplied water from the larger seawater line.  Both lines 
were plagued with blockages due to ice entrainment during operations in the 
heavy ice, especially when snow-covered, and in general uncontaminated seawater 
was only available when operating in open water or unconsolidated floes, or when 
on station within the ice.

The ship is fitted with a Seabird Model SBE-21 thermosalinograph, located in the 
Hydro Lab, operated and maintained by ASA personnel.  The unit is provided with 
a remote temperature sensor located near the inlet of the smaller uncontaminated 
seawater line, to provide an approximate sea surface temperature.  Data are 
logged continuously during operation by the ship's RTDAS.  Due to the failure of 
the pump on the thermosalinograph line, the thermosalinograph received water 
from the other seawater line during most of the cruise, and the remote 
temperature was thus unavailable.  A very approximate underway surface 
temperature during the later part of the cruise was calculated using an offset 
from the thermosalinograph temperature, calibrated against CTD mixed-layer 
temperatures during station work and against bucket thermometer temperatures 
during the transit from the last station to Hobart.

Although the seawater line in the Hydro Lab is provided with a vortex-type 
debubbler, it is plumbed in parallel with the thermosalinograph, and water for 
the latter instrument is not routinely debubbled.  Near the beginning of the 
cruise it became obvious that the very high noise level on the thermosalinograph 
salinity channel was caused by entrained air in the seawater line and the unit 
was replumbed to receive water from the outlet of the debubbler, which reduced 
the noise appreciably.


Underway pCO2

Underway measurements of the surface seawater pCO2 were made using a shower-type 
seawater-air equilibrator similar to that originally designed by Takahashi 
(Broecker and Takahashi, 1966).  Seawater from the same uncontaminated pumped 
water line which supplies the ship's thermosalinograph was used as a source for 
the CO2 equilibrator.  The equilibrator was located downstream of a vortex 
debubbler to remove air entrained with the water.  Air was continuously 
recirculated through the headspace of the equilibrator by means of a small air 
pump, and aliquots of this air were removed for analysis using a Licor infrared 
analyzer built into a fully automated analysis system.  Sample gases were dried 
by means of a countercurrent-flow permeation gas dryer immediately prior to 
analysis.  After eight samples of equilibrated air were analyzed, a single 
sample of atmospheric air pumped from a sampling point just ahead of the ship's 
bridge was similarly dried and analyzed.  This was followed by calibration of 
the instrument using four air-CO2 mixtures (150 to 450 ppm range) which are 
traceable to the WMO calibration scale of C. D. Keeling of SIO.  Barometric 
pressure (essentially the same as the pressure of equilibration) was measured at 
the time of each analysis by means of an AIR electronic barometer, and the 
temperature of equilibration was measured at the same time by means of a 
platinum resistance thermometer within the equilibrator, calibrated against a 
NIST-traceable mercury thermometer.  The entire cycle of eight equilibrated air 
samples, one atmospheric air sample, and four calibration gases required 
approximately one half hour, and was repeated continuously. Measurements were 
made whenever the ship was in open water outside the territorial waters of the 
Republic of South Africa or Australia, and to a limited extent while operating 
within the ice (due to the clogging of the seawater lines during ice 
operations).



C.  Tracers


C1. Chlorofluorocarbon Analysis
    (M. Mensch)

The CFC analysis on board as well as the sampling in flame-sealed glass ampoules 
for subsequent on-shore analysis were performed by Guy Mathieu and Manfred 
Mensch (Lamont-Doherty Earth Observatory of Columbia University, New York, PI 
Bill Smethie) and by Steve Covey (University of Washington, Seattle, PI Mark 
Warner).

The CFC lab was set up in the aft dry lab (N.B. Palmer room # 905).  This room 
was not optimal for the operation of the CFC measurement systems:

  o   There is no temperature control. This caused large long-term temperature 
      drifts.
  o   Whenever the outside door of the Baltic Room was open, the only access to   
      the Baltic Room was through the aft dry lab giving rise to considerable 
      short-term temperature and pressure fluctuations.
  o   The "fresh" air supply to this lab consisted at least partly of  
      recirculated air bearing the danger of serious contamination. 

The equipment was provided by Lamont-Doherty Earth Observatory.  Two gas 
chromatographic measurement systems, both designed and constructed at L-DEO, 
were used.  Both systems use the same technique for gas and water sample 
preparation, purification and concentration prior to injection into the 
chromatographic separation columns.

The two systems were based on different chromatographic pre-columns and 
analytical columns for the separation of the CFCs from more slowly eluting 
compounds (pre-column) and from each other (analytical column).  Both systems 
were configured to measure CFC11, CFC12, CFC113; system 1 also measured CCl4.  

On system 1, a capillary pre-column and analytical column (DB VRX, length 18 m 
and 57 m, respectively, film thickness 5 µm, I.D. 530 µm) were used.  Both 
columns were held in the oven of an HP8950 GC at 90°C for the first 9.1 minutes 
of the run.  After the complete elution of CCl4, the temperature was ramped up 
to 110°C within 0.5 min to clean the columns.  The detector was operated at a 
temperature of 280°C.  To minimize analysis time, pressure ramping was also 
used.  A relatively high pressure of 110 kPa during the first minute of each run 
rapidly transferred the CFCs from the trap to the pre-column.  The pressure was 
lowered to 70 kPa during the next minute and held at that level for 4.5 minutes. 
Then it was raised back to 110 kPa within 2 minutes.  The total length of the 
chromatographic run was 11 minutes.  The  analysis took about 15 minutes per 
sample.

System 2 used packed columns: a pre column of 80-100 mesh Porasil B packed in 
40-inch stainless steel tubing with 0.085-inch I.D., and an analytical column 
of 60-80 mesh Carbograph 1AC packed in 5-ft stainless steel tubing with 0.085-
inch I.D.  Both were held at 80°C in the oven of a Shimadzu GC 8A, the detector 
temperature was 260°C.  The analysis time per sample was about 11 min with 8 
min being used for the chromatographic run.

To avoid interference of N2O with CFC12, N2O was suppressed on  both systems by 
80-100 mesh mol sieve 5A packed into 4 in of 0.085-inch I.D. stainless steel 
tubing.  The mol sieve was operated at about 50°C.  The mol sieve was placed 
between the analytical column and the detector.  It was valved out of the gas 
stream before the elution of CFC11. 

Based on the originally-proposed cruise track with 1 station every 30 nm it was 
planned to obtain 30 samples on every other station for analysis on system 2 and 
at least 18 samples out of the deep part of the water column on the stations in 
between for analysis on system 1.  As the cruise progressed, this plan was 
adapted to the variable station spacing, bottom depth, weather and sea ice 
situation and other factors. 


Sample collection

Water samples were drawn into 100-ml precision ground glass syringes directly 
from the 10-l Niskin-type bottles before any other samples.  Close ended 
Luerlock fittings were used to seal filled syringes.  The samples were kept 
under slightly positive pressure by applying a rubber band around the syringe 
barrel.

Because of the loss of the primary rosette during a test cast, the 10-l bottles 
on the back-up rosette could not be tested for their CFC blank levels. By the 
time the spare rosette was ready for deployment, the ship was already close to 
the first station and in an oceanic region where no CFC-free waters can be found 
at any depth.  However, all O-rings of the Niskins were baked before use to 
remove CFCs; no suspicious variability in samples from the CFC minimum layer was 
detected.

To isolate the samples from lab air, filled syringes were stored in a deep sink 
that was continuously flushed with uncontaminated surface sea water from the 
ship's sea water line.

Unfortunately, whenever the ship was operating in ice covered waters the sea 
water pump had to be shut down.  During these times the samples were still kept 
in the same sink filled with sea water.
 

Sample analysis

From the syringes, the water samples were injected through a three-way valve 
into a calibrated glass volume (approximately 35 cc, calibrated to better than 
0.1%).  The three-way valve and the calibrated volume were flushed with sample 
water.  The water in the calibrated volume was subsequently transferred to a 
glass stripper chamber where the dissolved gases were purged with ultra high 
purity Nitrogen.  The released CFCs were concentrated by adsorption on a 
Unibeads cold trap at -60°C.  Subsequently the trap was isolated and heated.  

The desorped gases were backflushed into the chromatographic columns.  On system 
1, cooling was accomplished by immersing the trap into denatured alcohol cooled 
by a cryo cooler; heating to 100°C was achieved by immersion in boiling water.  
System 2 used an automated temperature control:  Cooling was done by liquid CO2, 
heating to 120°C was done electrically.  Fig. 3 shows typical chromatograms for 
samples with intermediate and low concentrations as well as a stripper blank. 
These chromatograms were obtained from system 2. 

On both systems, all chromatograms were acquired from the gas chromatograph by a 
Shimadzu Chromatopac CR601, which also controlled the valves, and on system 2, 
the automated trap.

Through an interface, the chromatograms were then transferred to a PC system 
where peak integration and data calculation were carried out.     


Calibration

For both systems, the response of the electron capture detector to different 
amounts of CFCs was calibrated by filling 10 different volumes with standard gas 
out of an Acculife compressed gas cylinder.  After relaxation to ambient 
temperature and pressure the standard gas was concentrated onto the cold trap 
and subsequently injected into the columns.  One of the standard volumes was 
used frequently (at least every other hour) to check for drifts in the 
detector's response.  The standard gas (CFCs in Nitrogen) was gravimetrically 
prepared at Brookhaven National Laboratories and calibrated at L-DEO relative to 
the SIO 1993 scale.  It will be recalibrated as soon as possible after the 
cruise.  Chromatograms from system 2 for different amounts of standard gas as 
well as a system blank are displayed in Fig. 4. 


Preliminary results

Profiles of CFC11, CFC12 and CFC113 from station 67 are shown in Fig. 5.  The 
intermediate CFC maximum at 250 m corresponds to a local minimum of the 
potential temperature and is associated with a maximum of the O2 concentration.

Fig. 6 shows a vertical section of the CFC11 concentration along 59.6°S from 
the Kerguelen Plateau into the Australian Antarctic Basin.  Surface 
concentrations are around 6.5 pM/kg along the entire section. In the eastern 
part of the section above the Kerguelen Plateau, CFC11 concentrations are less 
than 0.25 pM/kg below 500 m and drop below 0.1 pM/kg approximately  400 m off 
the bottom.  West of station 66, the penetration depth of the CFCs is much 
larger. The effect is most pronounced at stations 67 to 70, where subpolar 
waters are encountered.  Within the Australian Antarctic Basin, the lowest CFC11 
concentrations are around 0.15 pM/kg. 

Below 4000 m, CFC11 concentrations are higher than 1 pM/kg. The bottom values 
are around 1.3 pM/kg.


CFC intercomparison samples

On June 28, 1996, after all samples from the last WOCE station (# 108) were 
analyzed, a dedicated cast was made to collect water samples for an 
intercomparison of various European and U.S. CFC laboratories.  The rosette was 
lowered to 1600 m depth where the CFC minimum was located on the previous WOCE 
stations, and 17 Niskins were closed before the rosette was brought up to the 
mixed layer. At 35 m depth the remaining 19 Niskins were closed.  

Back on deck, five samples were drawn in succession from each of 16 deep 
Niskins. It took at most 15 minutes to draw all samples from each Niskin. The 
first and last sample were drawn into glass syringes as described above.  The 
analysis results from the first syringe provide the initial CFC concentration of 
the sample; the measurements from the second syringe give information about 
possible atmospheric contamination during the sampling interval.  A dedicated 
rig designed by the University of Bremen (PI Wolfgang Roether) and manufactured 
for L-DEO, was used to draw the other three samples into custom made glass 
ampoules which were flame-sealed within 15 min after sampling. 

Four samples each were drawn from 16 of the shallow Niskins. Again, the first 
sample was drawn into a syringe to establish the CFC concentration of the 
sampled water mass. The remaining three samples were drawn and sealed into glass 
ampoules.  (One of the deep, and three of the shallow Niskins were not 
accessible by the ampoule rigs and therefore not sampled at all.)

This special cast provided 48 samples each from two different depths sealed in 
glass ampoules.  The initial CFC concentrations were determined from the syringe 
samples, which were analyzed within ten hours of the completion of the cast. To 
prevent hydrolysis of CCl4, the ampoules were stored in one of the ships science 
coolers.  They were air-freighted back to Lamont for distribution to the CFC 
laboratories participating in the intercomparison experiment. 


C2. Helium, Tritium and 18O Sampling
    (D. Breger)

Helium, tritium and 18O samples were drawn at a total of 606 levels distributed 
over 34 stations The samples were stored for shipment to Lamont-Doherty Earth 
Observatory for shore-based extraction and analysis.

Helium samples were drawn immediately after CFCs. The helium samplers consisted 
of one-meter long copper tubes (holding 200 ml of sample) housed in one-meter 
long aluminum channels, each marked with cruise name, station number, Niskin 
number, nominal depth, unique sample identification number, and station date.  A 
seawater-cured tygon tube at the intake end delivered the sample from the Niskin 
bottle and a similar longer tygon tube at the outflow end ensured that no air 
would fall back into the copper tube during clamping, and directed the outflow 
away from neighboring samplers. After the intake tygon tube was cleared of air 
bubbles, the aluminum channel was struck several times while the copper tube was 
flushed with approximately 250-350 ml of water sample. The outflow end was then 
clamped with a ratchet wrench, after which the inflow end was clamped. The 
timing of sampling was logged at several points during the station. After the 
station, both ends of each channel were dipped in fresh water and towel dried. 
Fresh water was also sprayed into both ends of each copper tube and shaken out. 
The channels were immediately placed into their crates for storage and shipment.

Tritium samples were collected at the same stations and levels as helium, in 
one-liter amber glass bottles filled with argon.  At the outset of the cruise, 
all personnel who expected to be in the sampling room during the cruise were 
warned against wearing tritium-dial watches, and replacement digital watches 
were issued to those who required them. All bottles were labeled with cruise 
name, station number, Niskin number, nominal depth, unique sample identification 
number, and station date.  No delivery tube was used, and the bottle was not 
flushed prior to sample collection, although the caps were rinsed several times 
with the sample prior to closing.  The seawater sample poured directly from the 
Niskin spigot into the bottle, which was held as upright as possible to avoid 
argon loss, and as close to the spigot as possible without touching it.  The 
bottles were tightly capped and wiped dry.  After each sample was drawn the 
bottle was returned to its storage/shipping crate. After completion of the 
station, the caps were sealed with electrical tape to avoid working loose during 
shipment and the crates sealed and stored for shipment.  

Samples for 18O analysis were collected at the same stations and levels as 
helium and tritium in 30 ml clear glass bottles. All bottles were labeled with 
cruise name, station number, Niskin number, nominal depth, unique sample 
identification number, and station date.  No delivery tube was used. Both the 
bottles and caps were rinsed several times with the sample prior to collection, 
which was directly from the Niskin spigot, as close to it as possible without 
touching.  After sampling each bottles was tightly capped and wiped dry and 
returned to its box. After completion of the station the caps were sealed by 
electrical tape to avoid working loose during shipment.  When each box was full 
it was returned to its crate, which was sealed and stored for shipment.


C3. Radiocarbon Sampling
    (R. Key)

Section S04I is the tenth and final sample collection leg for the WOCE 
radiocarbon program.  Fig. 7 shows the sampling locations. Approximately 60% of 
the indicated stations were sampled only in the thermocline while the remainder 
were sampled throughout the water column. Normally 16 samples were collected for 
thermocline stations and 32 samples for full profiles. Approximately 4500 
samples were collected in total. Throughout the Indian Ocean survey, only small 
volume (AMS) radiocarbon samples were collected. The sample collection 
procedures described in Joyce (1991) were used. The sample tracking, analysis 
and quality control procedures outlined in Key (1996) and Key et al. (1996) and 
described in detail in references cited there, will be used to complete the 
laboratory phase of this program.

Prior to WOCE section S04I, the only radiocarbon data in the Southern Ocean 
sector of the Indian Ocean were from three GEOSECS stations (430-432). The goals 
of this leg were to collect a sufficient data set to describe the major features 
of the area, to identify and characterize any "new" bottom waters and to define 
the characteristics of the deep and bottom waters which flow north into the deep 
Indian (and Pacific) Ocean. The extreme lack of data coupled with these goals 
resulted in a different sampling strategy than used for the rest of the Indian 
(and Pacific) Ocean. Rather than intersperse 1 full water column sampling with 
1-2 thermocline profiles, all stations sampled for radiocarbon were sampled 
throughout the entire column. Station spacing was nominally 5 degrees of 
longitude (150nm) with somewhat closer spacing on the two north-south transects 
toward Antarctica. Thirty-one stations (816 samples) were sampled along section 
S04I.

Upon return to the U.S., these samples will be placed in the analytical queue at 
NOSAMS (WHOI). Prior to the beginning of the Indian Ocean survey, the advisory 
group (Key, Quay, Toggweiler & Schlosser) which determines analytical priority 
decided that the Indian samples would be done on a first-in first-out basis. If 
this is followed, these samples will be measured in approximately 3-4 years. A 
second alternative is that these samples will be run along with the S04 Pacific 
samples. If this is the decision, the samples will be completed in less than 2 
years.


C4. CO2 Sampling and Analysis
     (D. Chipman)

Sampling

Samples for CO2 and alkalinity analyses were drawn from the 10-liter Niskin 
bottles of the rosette sampler at selected stations

Samples for total CO2 (TCO2) analysis were collected in 250 ml glass reagent 
bottles with ground glass stoppers, sealed with silicone high-vacuum grease and 
were stored at room temperature prior to analysis.

Samples for pCO2 analysis were collected in 500 ml volumetric flasks with 
plastic-lined screw caps and were stored in the dark at approximately 4°C until 
analysis.

200 µl of 50%-saturated HgCl2 solution was added to both types of CO2 sample to 
prevent biological alteration of the CO2 


Total CO2 analysis

TCO2 analyses were made coulometrically, using the LDEO-design extraction 
system.  This system provides for automated calibration of the coulometer by 
means of injections of known quantities of pure CO2, whereas sample injection is 
manual, using glass syringes fitted with special adapters to provide constant 
sample volumes.  A jacketed electrochemical cell with constant-temperature 
circulator is used to insure the cell solutions are at constant temperature, in 
order to provide a consistent endpoint pH.  The anode and cathode compartments 
are separated by means of an agar plug in addition to the usual glass frit.  
Glass wool and a 0.2µ teflon filter are used to prevent aerosols from being 
carried to the electrochemical cell from the extraction tube, but no chemical 
clean-up or drying of the carrier gas is used between extraction and analysis.  
The carrier gas is CO2 -free air, provided by means of a chromatographic-type 
pure-air generator and Mallcosorb CO2 scrubber.

The instrument is calibrated at the beginning and end of the use of a given set 
of cell solutions, and after every 10-12 sample analyses, using 99.999% CO2.  
Since this type of calibration verifies the instrumental calibration but does 
not check the accuracy of the volume of seawater sample being injected, samples 
of calibrated reference material (CRM) provided by A. Dickson of SIO were run as 
unknowns at the beginning and end of the use of a given set of cell solutions 
(immediately after the initial and prior to or after the final instrumental 
calibration).  Each CRM was analyzed using each of the three syringes which were 
being used for sample injection, so that any change in the volume injected could 
be detected (none was ever noted).  Each set of cell solutions was retired after 
the instrumental calibration was observed to have changed by 0.10 to 0.15% from 
the startup value. 


pCO2 analysis

The partial pressure of CO2 at a constant temperature of 4°C was determined 
using the LDEO gas chromatograph-based analysis system (Chipman et al., 1993).  
Prior to analysis, samples (525 ml) are brought to temperature in a 
thermostatted bath and a headspace of approximately 38 ml is created by forcing 
this much water from the flask with air of known CO2 concentration.  The 
headspace air is recirculated through a gas disperser a few cm below the surface 
of the water, by means of a small air pump with teflon-covered rubber diaphragm.  
After approximately 20 minutes of equilibration, a 1 ml aliquot of the 
equilibrated air is injected into the carrier gas stream of a Shimadzu Mini-2 
gas chromatograph by means of a fixed-volume loop on a sampling valve.  The 
hydrogen carrier gas carries the air sample through a chromatographic pre-column 
and column packed with Chromosorb 102 (0.2 and 2 m), where the various 
components of the air are separated, and then through a ruthenium catalyst, 
where the CO2 reacts with the carrier to form methane and water.  The methane so 
produced in quantified by means of  a flame ionization detector and a computing 
integrator to determine the peak areas.  Each sample is re-equilibated and 
analyzed a second time before a second sample is connected and analyzed.  After 
four analyses (two separate samples), the gas chromatogaph is calibrated by 
means of injection of three air-CO2 mixtures (using the same loop on the 
injection valve) which are traceable to the WMO calibration scale of C. D. 
Keeling.  All samples are analyzed without the removal of water vapor, and 
corrections are applied for the perturbation of the TCO2 of the sample due to 
the equilibration process.   The pressure of equilibration is measured just 
prior to injection by means of a Setra (Model 270) electronic pressure 
transducer, the output of which is read (as a voltage) by the integrator. The 
response of the FID is calculated as a second-order polynomial using the values 
for the calibration gases run immediately before and after each set of unknowns, 
corrected for drift as a function of time between the calibration periods.


C5. Total Alkalinity
     (E. Peltola)

Samples for alkalinity analysis were collected in 500 cm3 glass reagent bottles.  
Total alkalinity (TA) was determined using a titration system similar to the one 
used in earlier studies (Millero et al., 1993) and to that developed by Bradshaw 
and Brewer (1988).  The titration system consisted of a Metrohm 665 Dosimat 
titrator and an Orion 720A pH meter that is controlled by a personal computer.  
Both the acid titrant in a water-jacketed burette and the seawater sample in a 
water-jacketed cell were maintained at a constant temperature of 25±0.1°C with a 
Neslab constant temperature bath.  The plexiglas water-jacketed cells used were 
similar to those used by Bradshaw et al. (1988), but a larger volume (about 200 
cm3) was used to increase the precision.  This cell had a fill-and-drain valve 
which increased the reproducibility of the cell volume. A LabWindows C program 
was used to run the titration, record the volume of the added acid and the emf 
of the electrodes using RS232 interfaces. The output of the computer program 
yields values of TA, total CO2 (TCO2), pH, the standard emf (E°) and the pK1 for 
the dissociation of carbonic acid. The titration is made by adding HCl to 
seawater past the carbonic acid end-point.  A typical titration records the emf 
reading after it become stable (0.05 mV) and adds enough acid to change the 
voltage by a pre-assigned increment (10 mV).  In contrast to the delivery of a 
fixed volume increment of acid, this method gives data points in the range of a 
rapid increase in the emf near the endpoint.  A full titration (25 points) takes 
about 20 minutes. Using two systems a 36-bottle station cast can be completed in 
9 hours. The electrodes used to measure the emf of the sample during a titration 
consisted of a ROSS glass pH electrode and an Orion double junction Ag, AgCl 
reference electrode.

The HCl acid solutions (20 L) used throughout the cruise were made, 
standardized, and stored in 500 cm3 glass bottles in the laboratory for use at 
sea.  The 0.24790 M HCl solutions were made from 1 M Mallinckrodt standard 
solutions in 0.45 M NaCl to yield an ionic strength equivalent to that of 
average seawater (0.7 M).  The acid was standardized by Dr. Millero's laboratory 
using a potentiometric technique and by Dr. Dickson's laboratory by using a 
coulometric technique (Taylor and Smith, 1959).

The volumes of the cells used at sea were determined in the laboratory by 
weighing the cells filled with degassed Millipore Super Q water.  The density of 
water at the temperature of the measurements (25°C) was calculated from the 
international equation of state of seawater (Millero and Poisson, 1981).  The 
nominal volumes of all the cells were about 200 cm3 and the values were 
determined to 0.03 cm3.

The volume of HCl delivered to the cell is traditionally assumed to have small 
uncertainties and equated to the digital output of the titrator.  Calibrations 
of the burettes of the Dosimats with water at 25°C indicate that the systems 
deliver 3.000 cm3 (the value for a titration of seawater) to a precision of 
0.0004 cm3. This uncertainty results in an error of  0.4 µmol kg-1 in TA and 
TCO2.  

A number of titrations were made on TCO2 Certified Reference Material (Batch # 
31) before, during and after the cruise. Duplicate samples were taken from some 
Niskin bottles from the surface and from 800 meters for same-cell and between-
cell reproducibility at sea. Internal consistency of the cells was checked every 
day by titrating Certified Reference Material and surface seawater.



D. Current meter deployments
   (T. Whitworth)

Nine self-reporting current meters were deployed as part of S04I.  The 
instruments were model 9407 vector-averaging current meters manufactured by 
Alpha Omega Computer Systems, Inc. of Corvallis, Oregon.   The current meter 
consists of a computer/controller and Argos transmitter in a 17" glass ball 
enclosed by a plastic hardhat, a rotor and vane assembly, a timed release and 
anchor, all assembled and packed in a single shipping crate.  The meters were 
preprogrammed at Oregon State University to control data collection, storage,  
transmission and the releases were preprogrammed to activate on March 15, 1997, 
the approximate date of the local ice minimum period in the Indian Ocean sector 
of the Southern Ocean.  The only action required for deployment is to confirm 
that the instrument is operating, that the release is properly programmed, and 
to select the length of mooring line between the anchor and the current meter.  
The meters were launched by hand by three people with the assistance of a small 
crane to lift the anchor over the rail to the water's edge.

The current meters were programmed to burst sample in a 10-minute window every 
hour and to average 24 bursts to provide daily averages of current speed, 
direction, temperature and pressure.  The releases consist of a monofilament 
line passing through two redundant heating elements that melt the monofilament 
at the time programmed on the on-board computer.  When the current meter 
surfaces, it reports its data via Argos satellite, repeating the message until 
the transmitter batteries expire.


References

Atlas, E. L., Hager, S. W., Gordon, L. I., and Park, P.K., (1971) A Practical 
    Manual for Use of the Technicon Auto-Analyzer(r) in  Seawater  Nutrient  
    Analyses  Revised, Technical  Report  215,  Reference 71-22, p. 49, Oregon 
    State University, Department of Oceanography.

Armstrong, F. A. J., Stearns, C. R., and Strickland, J. D. H., (1967) The  
    measurement of upwelling and subsequent biological processes by means of the 
    Technicon Autoanalyzer and associated equipment, Deep-Sea Research, 14, 381- 
    389.

Bernhardt, H. and Wilhelms, A., (1967) The continuous determination of low level 
    iron, soluble phosphate and total phosphate with the AutoAnalyzer, 
    Technicon Symposia, I, pp. 385-389.

Bradshaw, A.L., and P.G. Brewer, 1988, High precision measurements of alkalinity 
    and total carbon dioxide in seawater by potentiometric titration - 1 
    Presence of unknown protolyte(s)?, Mar. Chem., 23, 69-86.

Broecker, W. S. and Takahashi, T., 1966, Calcium carbonate precipitation on the 
    Bahama Banks. Jour. Geophys. Res., 71, 1575-1602.

Carpenter, J. H., (1965) The Chesapeake Bay Institute technique for the Winkler 
    dissolved oxygen method, Limnology and Oceanography, 10, 141-143.

Carter, D. J. T., (1980) Computerised Version of Echo-sounding Correction Tables 
    (Third Edition), Marine Information and Advisory Service, Institute of  
    Oceanographic Sciences, Wormley, Godalming, Surrey. GU8 5UB. U.K.

Chipman, D. W., Mara, J. and Takahashi, T., 1993, Primary productivity at 47oN 
    and 20°W in the North Atlantic Ocean: A comparison between the 14C 
    incubation method and the mixed layer carbon budget. Deep-Sea Res., 40, 151-
    169.

Culberson, C. H. and Williams, R. T., et al., (1991) A comparison of methods for 
    the determination of dissolved oxygen in seawater, Report WHPO 91-2,  WOCE 
    Hydrographic Programme Office.

Gordon, L. I., Jennings, J. C., Jr., Ross, A. A., and Krest, J. M., (1992) A 
    suggested Protocol for Continuous Flow Automated Analysis of Seawater 
    Nutrients in the WOCE Hydrographic Program and the Joint Global Ocean Fluxes 
    Study, Grp. Tech Rpt 92-1, OSU College of Oceanography Descr. Chem Oc.

Hager, S. W., Atlas, E. L., Gordon, L. D., Mantyla, A. W., and Park, P. K., 
    (1972) A comparison at sea of manual and autoanalyzer analyses of phosphate, 
    nitrate, and silicate, Limnology and Oceanography, 17, 931-937.

Joyce, T.M., Ed., 1991, WHP operations and methods, WHPO 91-1, WOCE Report No. 
    68/91.

Key, R.M., WOCE Pacific Radiocarbon Program, 1996, Radiocarbon, in press.

Key, R.M., P.D. Quay and NOSAMS, 1996, WOCE AMS Radiocarbon I: Pacific Ocean 
    Results: P6, P16 & P17, Radiocarbon, in press.

Millard, R. C., Jr., (1982) CTD calibration and data processing techniques at  
    WHOI using the practical salinity scale," Proc. Int. STD Conference and 
    Workshop, p. 19, Mar. Tech. Soc., La Jolla, Ca.

Millero, F.J., and A. Poisson, 1981, International one-atmosphere equation of 
    state of seawater, Deep-Sea Res., 28, 625-629. Owens, W. B. and Millard, R. 
    C., Jr., (1985) A new algorithm for CTD oxygen calibration, J. Am. 
    Meteorological Soc., 15, 621.

Taylor, J.K., and S.W. Smith, 1959, Precise coulometric titration of acids and 
    bases, J. Res. Natl. Bur. Stds., 63A, 153-159.

UNESCO, (1981) Background papers and supporting data on the Practical Salinity  
    Scale, 1978, UNESCO Technical Papers in Marine Science, No. 37, 144.



S04I Final Report for AMS 14 C Samples 
(Robert M. Key) 
April 19, 1999 


1.0 General Information 

WOCE cruise S04I was carried out aboard the R/V N. B. Palmer in the southern 
Indian Ocean. The WHPO designation for this cruise was 320696_3. Thomas 
Whitworth III (TAMU) and James H. Swift (SIO) were the co-chief scientists. The 
cruise constituted the Indian Ocean portion of WOCE line S4, a meridional 
circumnavigation of Antarctica at a nominal latitude of 60S. This segment 
covered the longitudes 20°E to 120°E. A total of 108 full depth CTD/Rosette 
stations were carried out. The cruise departed Cape Town, South Africa on May 3 
and ended at Hobart Tasmania on July 4, 1996. On June 8, science operations were 
suspended for seven days when the Palmer was diverted to Mirnyy Station in the 
Davis Sea to deliver emergency food supplies. The reader is referred to cruise 
documentation provided by the chief scientists as the primary source for cruise 
information. This report covers details of the small volume radiocarbon samples. 
The AMS station locations are shown in Figure 1 and summarized in Table 1. A 
total of 816 D 14 C samples were collected at 31 stations 

TABLE 1. S04I D 14 C station locations. 
                                                    Bottom
             Station   Month   Latitude  Longitude Depth (m) 
             -------  -------  --------  --------- ---------
                1     5/16/96  -58.008    20.006     5412 
                7     5/18/96  -61.399    25.749     5243 
               13     5/20/96  -64.000    30.017     5135 
               23     5/22/96  -65.134    37.349     4874 
               26     5/24/96  -64.465    41.619     4435 
               29     5/25/96  -63.736    46.408     4270 
               35     5/28/96  -65.456    53.363      501 
               36     5/28/96  -65.371    53.264     1303 
               38     5/28/96  -65.104    53.018     2468 
               40     5/29/96  -64.435    53.072     4200 
               42     5/29/96  -63.498    53.682     4790 
               46     5/30/96  -63.501    58.335     4566 
               51      6/1/96  -62.361    64.406     4365 
               55      6/3/96  -61.962    70.017     4165 
               58      6/4/96  -61.806    74.982     4000 
               62      6/5/96  -61.417    80.489     2480 
               66      6/6/96  -59.696    84.850     2024 
               68      6/7/96  -59.660    85.248     4494 
               70      6/7/96  -59.520    86.221     4304 
               73     6/14/96  -65.330    91.475      553 
               76     6/15/96  -64.859    93.004     1808 
               78     6/16/96  -64.464    92.481     3060 
               80     6/16/96  -63.653    91.737     3629 
               84     6/18/96  -63.092    86.007     3809 
               87     6/20/96  -62.001    90.001     4020 
               90     6/22/96  -62.286    94.670     3848 
               93     6/23/96  -62.335    99.558     4316 
               98     6/24/96  -62.104   105.269     4297 
              102     6/26/96  -62.244   110.607     3986 
              105     6/26/96  -62.002   115.331     4255 
              108     6/27/96  -62.000   120.000     4194


2.0 Personnel 

14 C sampling for this cruise was carried out by Robert M. Key (Princeton 
University). 14 C (and accompanying 13 C) analyses were performed at the 
National Ocean Sciences AMS Facility (NOSAMS) at Woods Hole Oceanographic 
Institution. R. Key collected the data from the originators, merged the files, 
assigned quality control flags to the 14 C and submitted the data files to the 
WOCE office (4/99). R. Key is P. I. for the 14 C data and NOSAMS for the 13 C 
data. 


3.0  Results 

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

3.1  Hydrography Hydrography from this leg has been submitted to the WOCE office 
     by the chief scientist and described in the hydrographic report. 

3.2  14C 

The D 14 C values reported here were originally distributed in a NOSAMS data 
report (NOSAMS, 1999), February 16, 1999. That reports included results which 
had not been through the WOCE quality control procedures. This report supersedes 
that data distribution. 

All of the AMS samples from this cruise have been measured. Replicate 
measurements were made on 4 water samples. These replicate analyses are 
tabulated in Table 2. The table shows the error weighted mean and uncertainty 
for each set of replicates.


      Sta-Cast-Bottle   D 14 C   Err   E.W. Mean(a)  Uncertainty(b) 
      ---------------  --------  ----  ------------  --------------
          51-1-9       -161.31   2.92   -167.40         2.62 
                       -176.84   2.91     
          51-1-10      -167.33   3.26   -167.40         2.59 
                       -167.51   4.29     
          58-1-26      -151.72   5.74   -155.78         3.49 
                       -156.65   2.67 
          70-1-5       -176.29   4.42   -176.06         3.46 
                       -175.69   5.55    
          ---------------------------------------------------------
          a. Error weighted mean reported with data set 
          b. Larger of the standard deviation and the error weighted 
             standard deviation of the mean.

Table 2: Summary of Replicate Analyses 


Uncertainty is defined here as the larger of the standard deviation and the 
error weighted standard deviation of the mean. For these replicates, the simple 
average of the normal standard deviations for the replicates is 1.0o/oo. This 
precision estimate is lower than the average error for the time frame over which 
these samples were measured (Jul. 1996 -Dec. 1998) and lower than the overall 
mean error for Pacific WOCE samples (Elder, et. al., 1998). Note that the errors 
given for individual measurements in the final data report (with the exception 
of the replicates) include only counting errors, and errors due to blanks and 
backgrounds. The uncertainty obtained for replicate analyses is generally a bet-
ter estimate of the true error since it includes errors due to sample 
collection, sample degassing, etc. Close examination of the data along 67°S in 
the deep water indicates that 4o/oo is a more realistic of the true error 
associated with this data set. 


4.0 Quality Control Flag Assignment 

Quality flag values were assigned to all D 14 C measurements using the code 
defined in Table 0.2 of WHP Office Report WHPO 91-1 Rev. 2 section 4.5.2. 
(Joyce, et al., 1994). Measurement flags values of 2, 3, and 6 have been 
assigned. The choice between values 2 (good) and 3 (questionable) involves some 
interpretation. There is little overlap between this data set and any existing 
14 C data, so that type of comparison was difficult. In general the lack of 
other data for comparison led to a more lenient grading on the 14 C data. 

When using this data set for scientific application, any 14 C datum which is 
flagged with a "3" should be carefully considered. When flagging 14 C data, the 
measurement error was taken into consideration. That is, approximately one-third 
of the 14 C measurements are expected to deviate from the true value by more 
than the measurement precision. No measured values have been removed from this 
data set. Table 3 summarizes the quality control flags assigned to this data 
set. For a detailed description of the flagging procedure see Key, et al. 
(1996). 


Table 3: Summary of Assigned Quality Control Flags 

                          Flag  Number 
                          ----  ------
                           2     803 
                           3      6 
                           4      0 
                           5      4 
                           6      3(a)  
                       ------------------
                       (a)Some replicates 
                          flagged 3 or 4

5.0  Data Summary 

Figures 2-6 summarize the D 14 C data collected on this leg. Only D 14 C 
measurements with a quality flag value of 2 ("good") or 6 ("replicate") are 
included in each figure. Figure 2 shows the D 14 C values with 2s error bars 
plotted as a function of pressure. The mid depth D 14 C minimum which normally 
occurs around 2500 meters in most of the Pacific is absent in this section. In 
fact, there is very little variation in the deep and bottom water. All of the 
samples for the entire cruise collected at a depth greater than 1000 meters have 
a mean D 14 C = -153.8±7.2o/oo with a substantial fraction of this variance due 
to the samples collected very near the Antarctic slope. This result compares 
remarkably well with the mean of -156.0±8.5o/oo calculated for the WOCE Pacific 
Antarctic section (S4P). Figure 3 shows the D 14 C values plotted against 
silicate. The straight line shown in the figure is the least squares regression 
relationship derived by Broecker et al. (1995) based on the GEOSECS global data 
set. According to their analysis, this line (D 14 C = -70 -Si) represents the 
relationship between naturally occurring radiocarbon and silicate for most of 
the ocean. They interpret deviations in D 14 C above this line to be due to 
input of bomb-produced radiocarbon, however, they note that the technique can 
not be applied at high latitudes as confirmed by this data set. With the 
exception of the very near surface waters, this region of the Pacific shows no 
change since GEOSECS which strongly implies that the data in Figure 3 indicates 
a failure of the technique in this area rather than bomb-produced contamination 
throughout the water column. 

Figure 4 shows all of the S04I radiocarbon values plotted against potential 
alkalinity normalized to a salinity of 35 (defined as [alkalinity + nitrate]* 
35/ salinity). The straight line is the regression fit (14 C = -68 -(PALK_ 35 
-2320) derived by S. Rubin (LDEO) to all of the GEOSECS results for waters which 
were assumed to have no bomb-produced 14 C (depths greater than 1000 meters, but 
including high latitude samples). Preliminary investigation indicates that this 
new method for separating bomb-produced and natural 14 C works in high latitude 
waters. For this data set it appears that the regression intercept derived from 
the GEOSECS data may be a bit too low. Regardless, if the function is valid, 
then for these data, waters which have alkalinity values less than ~2400 mmole/
kg have a significant amount of bomb-produced radiocarbon. If this is true, and 
if the values have changed little since GEOSECS, then most of the bomb 
contamination had to have been distributed throughout most of the water column 
even as early as the mid 1970's. 

Figures 5-7 show gridded sections of the D 14 C data. The data were gridded 
using the "loess" methods described in Chambers et al. (1983), Chambers and 
Hastie (1991), Cleveland (1979) and Cleveland and Devlin (1988). 

Figure 5 shows the main zonal cruise section along ~62°S. The colors in the 
image indicate D 14 C while the contours are CFC-11 concentration (pmol/kg; 
preliminary data from Bill Smethie (LDEO) and Mark Warner (UW)). Significant 
resolution is lost in the deep water D 14 C since most of the variability is 
near the surface. Nevertheless, a strong correlation in the two distributions 
is immediately apparent. The bottom waters both east and west of the Kerguelen 
Ridge (~ 80°E) have appreciable chlorofluorocarbon concentrations and are most 
likely contaminated with bomb-produced radiocarbon. The highest near bottom 
(pressure >3750dB) D 14 C values along this section range between -140o/oo and 
-130o/oo and are comparable to near bottom waters at similar latitudes in the 
Pacific (Key and Schlosser, 1999). Figure 6 and Figure 7 show contoured sections 
of the D 14 C distribution along 65°E and 90°E respectively. Note that the 
contour interval used in the two figures is different. The 65°E and 90°E 
sections clearly show penetration of bomb radiocarbon along the Antarctic 
continental slope. 


6.0 References and Supporting Documentation 

Broecker, W. S., S. Sutherland and W. Smethie, Oceanic radiocarbon: Separation 
    of the natural and bomb components, Global Biogeochemical Cycles, 9(2), 
    263-288, 1995. 

Chambers, J. M. and Hastie, T. J., 1991, Statistical Models in S, Wadsworth & 
    Brooks, Cole Computer Science Series, Pacific Grove, CA, 608pp. 

Chambers, J. M., Cleveland, W. S., Kleiner, B., and Tukey, P. A., 1983, 
    Graphical Methods for Data Analysis, Wadsworth, Belmont, CA. 

Cleveland, W. S., 1979, Robust locally weighted regression and smoothing 
    scatterplots, J. Amer. Statistical Assoc., 74, 829-836. 

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

Elder, K. L. A. P. McNichol and A. R. Gagnon, Reproducibility of seawater, 
    inorganic and organic carbon 14 C results at NOSAMS, Radiocarbon, 40(1), 
    223-230, 1998 

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

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

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

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

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



Figure Legends

Figure 1: AMS 14 C station map for WOCE S04I. 

Figure 2: D 14 C results for S04I stations shown with 2s error bars. Only those 
          measurements having a quality control flag value of 2 or 6 are 
          plotted.

Figure 3: D 14 C as a function of silicate for S04I AMS samples. The straight 
          line shows the relationship proposed by Broecker, et al., 1995 (D 14 C 
          = -70 -Si with radiocarbon in o/oo and silicate in mmol/kg). Two-sigma 
          error bars are given for the D 14 C measurements. 

Figure 4: Based on the new method devised by S. Rubin, the samples which plot 
          above the line and have potential alkalinity values less than about 
          2400 mmole/kg are contaminated with bomb-produced 14 C.. 

Figure 5: D 14 C concentrations, along main east-west section of S04I at 
          approximately 62°S, are indicated by color. Contour lines are 
          preliminary CFC-11 concentrations (pmol/kg).

Figure 6: D 14 C along ~65°E near the Antarctic slope. The near bottom values 
          along the lower slope indicate entrainment of "new" bottom water. 

Figure 7: D 14 C along ~90°E near the Antarctic slope. The near bottom values 
          along the lower slope indicate entrainment of "new" bottom water.




WHPO-SIO DATA PROCESSING NOTES

Date      Contact      Data Type       Data Status Summary
--------  -----------  --------------  ------------------------------------
01/23/98  Rutz         BTL/CTD         Data are NonPublic

01/23/98  Whitworth    SUM/BTL         Submitted
          
07/29/98  Johnson      DOC             S04I is next on ODF CTD report agenda
          
05/05/99  Swift        Cruise ID       Confirming Whitworth as Chi. Sci. 
          Regarding S4I, Nowlin had foot surgery shortly before the cruise 
          and cancelled. All my interactions since have been with Tom 
          Whitworth. So, yes, he is Chief Scientist and chief contact for 
          the R/V Palmer S4I cruise. Jim
          
03/24/00  Schlosser    He/Tr           Data are Public 
          As mentioned in my recent message, we will release our data with a 
          flag that indicates that they are not yet final. We started the 
          process of transferring the data and we will continue with the 
          transfer during the next weeks. I had listed the expected order of 
          delivery in my last message.
          
05/05/00  Key          DELC14          Data are NonPublic 
          Thank you for the notice regarding S4I C14 and the new CD-ROM. The 
          proprietary period for this data (2 years after measurement) ends 
          2/16/2001 or later (I'm not sure that the measurements for this cruise 
          are even finished). I do not want these data made public yet.
          
05/09/00  Whitworth    CTD/BTL         Data are Public 
          The 1996 Palmer S4I data may be made public. I am almost certain that 
          my co-Chief Scientist will agree.
          
06/08/00  Bartolacci   CTD/BTL/CFCs    Website Updated  data unencrypted

09/13/00  Kozyr        CO2             Final Data Submitted
          TCARBN, ALKALI, PCO2, PCO2TMP  
          I have just put the final and public CO2-related data for the WOCE 
          Section S4I (EXPOCODE 320696_2) in your INCOMING ftp area. The data 
          consist of TCARBN, ALKALI, PCO2, PCO2TMP, and quality flags. The data 
          were submitted to CDIAC by Taro Takahashi of LDEO and Frank Millero of 
          RSMAS.


Date      Contact      Data Type       Data Status Summary
--------  -----------  --------------  ------------------------------------
06/20/01  Johnson      CTD             Data Update; Processing error corrected
          revised data available by ftp  ODF has discovered a small error in the 
          algorithm used to convert ITS90 temperature calibration data to 
          IPTS68.  This error affects reported Mark III CTD temperature data for 
          most cruises that occurred in 1992-1999.  A complete list of affected 
          data sets appears below.

          ODF temperature calibrations are reported on the ITS90 temperature 
          scale.  ODF internally maintains these calibrations for CTD data 
          processing on the IPTS68 scale.  The error involved converting ITS90 
          calibrations to IPTS68.  The amount of error is close to linear with 
          temperature: approximately -0.00024 degC/degC, with a -0.00036 degC 
          offset at 0 degC.  Previously reported data were low by 0.00756 degC 
          at 30 degC, decreasing to 0.00036 degC low at 0 degC.  Data reported 
          as ITS90 were also affected by a similar amount.  CTD conductivity 
          calibrations have been recalculated to account for the temperature 
          change.  Reported CTD salinity and oxygen data were not significantly 
          affected.
          
          Revised final data sets have been prepared and will be available soon 
          from ODF (ftp://odf.ucsd.edu/pub/HydroData).  The data will eventually 
          be updated on the whpo.ucsd.edu website as well.
          IPTS68 temperatures are reported for PCM11 and Antarktis X/5, as 
          originally submitted to their chief scientists.  ITS90 temperatures 
          are reported for all other cruises.

          Changes in the final data vs. previous release (other than temperature 
          and negligible differences in salinity/oxygen):
          S04P:  694/03 CTD data were not reported, but CTD values were reported 
          with the bottle data.  No conductivity correction was applied to these 
          values in the original .sea file.  This release uses the same 
          conductivity correction as the two nearest casts to correct salinity.
          AO94:  Eight CTD casts were fit for ctdoxy (previously uncalibrated) 
          and resubmitted to the P.I. since the original release.  The WHP-
          format bottle file was not regenerated.  The CTDOXY for the following 
          stations should be significantly different than the original .sea file 
          values:
              009/01 013/02 017/01 018/01 026/04 033/01 036/01 036/02 
          I09N: The 243/01 original CTD data file was not rewritten after 
          updating the ctdoxy fit.  This release uses the correct ctdoxy data 
          for the .ctd file.  The original .sea file was written after the 
          update occurred, so the ctdoxy values reported with bottle data should 
          be minimally different.
          ======================================================================
          DATA SETS AFFECTED:
          WOCE Final Data - NEW RELEASE AVAILABLE:
            WOCE Section ID   P.I.                 Cruise Dates
            ------------------------------------------------------------
            S04P             (Koshlyakov/Richman)  Feb.-Apr. 1992
            P14C             (Roemmich)            Sept. 1992
            PCM11            (Rudnick)             Sept. 1992
            P16A/P17A        (JUNO1)  (Reid)       Oct.-Nov. 1992
            P17E/P19S        (JUNO2)  (Swift)      Dec. 1992 - Jan. 1993
            P19C             (Talley)              Feb.-Apr. 1993  
            P17N             (Musgrave)            May-June 1993
            P14N             (Roden)               July-Aug. 1993
            P31              (Roemmich)            Jan.-Feb. 1994
            A15/AR15         (Smethie)             Apr.-May 1994   
            I09N             (Gordon)              Jan.-Mar. 1995
            I08N/I05E        (Talley)              Mar.-Apr. 1995
            I03              (Nowlin)              Apr.-June 1995
            I04/I05W/I07C    (Toole)               June-July 1995
            I07N             (Olson)               July-Aug. 1995
            I10              (Bray/Sprintall)      Nov. 1995   
            ICM03            (Whitworth)           Jan.-Feb. 1997

          non-WOCE Final Data - NEW RELEASE AVAILABLE:
            Cruise Name       P.I.                 Cruise Dates
            ------------------------------------------------------------
            Antarktis X/5    (Peterson)            Aug.-Sept. 1992
            Arctic Ocean 94  (Swift)               July-Sept. 1994
            Preliminary Data - WILL BE CORRECTED FOR FINAL RELEASE ONLY
              NOT YET AVAILABLE: 
            Cruise Name       P.I.                 Cruise Dates
            ------------------------------------------------------------
            WOCE-S04I        (Whitworth)           May-July 1996   
            Arctic Ocean 97  (Swift)               Sept.-Oct. 1997
            HNRO7            (Talley)              June-July 1999
            KH36             (Talley)              July-Sept. 1999

          "Final" Data from cruise dates prior to 1992, or cruises which 
              did not use NBIS CTDs, are NOT AFFECTED.
          post-1991 Preliminary Data NOT AFFECTED:
            Cruise Name       P.I.                 Cruise Dates
            ------------------------------------------------------------
            Arctic Ocean 96  (Swift)               July-Sept. 1996
            WOCE-A24 (ACCE)  (Talley)              May-July 1997
            XP99             (Talley)              Aug.-Sept. 1999
            KH38             (Talley)              Feb.-Mar. 2000
            XP00             (Talley)              June-July 2000          


Date      Contact      Data Type       Data Status Summary
--------  -----------  --------------  ------------------------------------
09/13/00  Kozyr        CO2             Final Data submitted
          I have just put thefinal and public CO2-related data for the WOCE 
          Section S4I (EXPOCODE 320696_2) in your INCOMING ftp area.
          The data consist of TCARBN, ALKALI, PCO2, PCO2TMP, and quality flags.
          The data were submitted to CDIAC by Taro Takahashi of LDEO and Frank 
          Millero of RSMAS.

12/11/00  Uribe        DOC             Submitted
          2000.12.11 KJU
          File contained here is a CRUISE SUMMARY and NOT sumfile. 
          Documentation is online.
          
          2000.10.11 KJU
          Files were found in incoming directory under whp_reports. This 
          directory was zipped, files were separated and placed under proper 
          cruise. All of them are sum files.
          Received 1997 August 15th.
          
06/21/01  Uribe        CTD/BTL         Website Updated; EXCHANGE File put online

10/02/01  Diggs        SUM             Data Update; SUM file format corrected
          At Mary Johnson's request I have corrected line 23-24 (Cast 1, 
          Station 1 EN) which needed a formatting correction. That line 
          needed a line feed and an expocode. Old file moved to original and 
          all documentation updated.
          
10/12/01  Key          DELC14, DELC13  Submitted; reformatting needed
          To save time the S4I file is attached. I included c13 as well as 
          c14. Note that my software isn't aware of the "official" number of 
          decimal places. If too many are listed the values can be rounded, 
          if too few just add the appropriate number of "0"'s.
          
12/11/01  Key          DELC14          DQE Report Submitted to WHPO
          
12/26/01  Uribe        CTD             Website Updated; EXCHANGE File Added
          CTD has been converted to exchange using the new code and put 
          online.
          
01/03/02  Hajrasuliha  CTD             Internal DQE completed
          created .ps files. created *check.txt files.
          

Date      Contact      Data Type       Data Status Summary
--------  -----------  --------------  ------------------------------------
04/01/02  Buck         DELC13          Data moved from incoming
          Moved data from /usr/export/html-
          public/cgi/SUBMIT/INCOMING/20020401.102545_GERLACH_SO4I to 
          /usr/export/html-
          public/data/onetime/southern/s04/s04i/original/20020401.102545_GER
          LACH_SO4I. Directory contains a readme file from the data 
          submission page and a data file with delc13.
          
04/12/02  Buck         C14             Data moved from incoming; Header added
          Moved S4I.C14 data from /usr/export/ftp-incoming to 
          s04/s04i/original/20020410_KEY_S4I_C14. Data is a EXCHANGE file 
          and contains C14 data. Added this line to header # S04I, 320696_3, 
          Key

05/08/02  Anderson     C14/C13/CO2/He  Data merged into online file  
          Merged DELC13, TCARBN, ALKALI, DELC14, C14ERR, PC02, HELIUM, DELHE3, 
            and DELHER into the .sea file and put online.
          Merged DELC14 and C14ERR from S4I.C14 found in web site: 
            ...southern/s04/s04i/original/20002010_KEY_S4I_C14 
               into the online file.
          Merged DELC13 from 20020401.102545_GERLACH_S04I_whpo_s04i.txt found in 
               web site: 
            ...southern/s04/s04i/original/20020401.102545_GERLACH_S04I 
               into the online file.
          Merged TCARBN, ALKALI, and PCO2 from s4icarb.txt found in web site: 
            ...southern/s04/s04i/original/2000.09.13_S4I_CARB_BARTOLACCI 
               into the online file.

          NOTE:  Except for the above merged data the designation for missing 
                 values is -9 there is no decimal or decimal places.

          Merged HELIUM, DELHE3, and DELHER.  Received data from Bob Newton 
            on April 30, 2002.file in: 
            .../southern/s04/s04i/20020430_S04I_HELIUM_BNEWTON
          Some of the DELHE3 values are very strange ie 9367.3822, but they 
            are flagged as 4.
          There was no tritium in this file.
          
05/09/02  Anderson     DELHE3          Update Needed; Some values out of range  
          Bob,
          I have been merging the helium data you sent in April and have a 
          question. In some cases the delhe3 values are very out of line with 
          the rest of the data. Granted they are flagged 4, but since they 
          exceed in both directions the range listed in the WOCE manual, our 
          programs choke on them.  What should we do with these samples (see 
          sta. 2, samp. 34, 25, 24, 22, and 20)?
          
          Also, occasionally (see sta. 40, samp. 7) there is a delher value 
          when there is no delhe3 value.  What should be done with these?
          

Date      Contact      Data Type       Data Status Summary
--------  -----------  --------------  ------------------------------------
05/09/02  Newton       DELHE3          Answer to Sarilee's query   
          These far-out-of-range values are typically from samples where 
            something has gone drastically wrong in the extraction process (loss 
            of vacuum, cracked ampule, etc.).  I've reported them as "4" rather 
            than "5" just in case you guys wanted to keep track of where samples 
            were taken; and where they were not.  But since, for reasons such as 
            those cited above, we were not able to make a legitimate measurement 
          I don't see any problem in changing their status to "5" (no value 
            reported) and changing the measurement values to "-999". Peter: does 
            that seem right to you?
          Where there is no delhe3 value reported, the delhe3_err value should 
            be "-999".
          
05/09/02  Anderson     DELHE3/DELHER   Website Updated
          Reformatted data online, new exchange file online.  Made some 
            changes to the DELHE3 and DELHER re Bob Newton's response to 
            my e-mail. 
          Made new exchange file. 

12/10/02  Kappa        DOC             cruise report updated
          Added:
             Discussion and table of ALACE deployments
             Discussion and table of current meter deployments
             Section on underway measurements including
                Navigation and Bathymetry
                Meteorological Observations
                Adcp
             Atmospheric Chemistry
                CO2 Analysis
                CFC Analysis
                Thermosalinograph and underway pCO2
                Underway pCO2
             Hydrographic Measurements including
                Water Sampling Package (Rosette and CTD)
             CTD Measurements
                CTD Data Processing
             Bottle Measurements
                Bottle Data Processing
             Salinity Analysis
             Oxygen Analysis
             Nutrient Analysis
             Chlorofluorocarbon Analysis
                Sample collection
                Sample analysis
                Calibration
                Preliminary results
                CFC intercomparison samples
             Helium, Tritium and 18O Sampling
             Radiocarbon Sampling
             CO2 Sampling and Analysis
                Sampling
                Total CO2 analysis
                pCO2 analysis
             Total Alkalinity
             Current meter deployments
             References
             Final Report for S04I AMS 14C Samples
             These Data Processing Notes
          

Date      Contact      Data Type       Data Status Summary
--------  -----------  --------------  ------------------------------------
02/11/03  Diggs        He/Tr           Data Ready to be Merged  
            (Same as A24 he/tr data)
          Data files (xls and csv) were sent to ODF email account. Once found, 
            these data were place in the holding directory under 
            20020522_S04I_HE-TR_NEWTON and are ready to merge into the bottle 
            file.
          
03/12/03  Muus         DELC13          Data online corrected  
          Decimal-1 data replaced with decimal-2 data  Replaced DELC13 decimal-
            1-data with decimal-2-data from same original data files.

          Notes on S04I             Mar 12, 2003      D. Muus
          1. Replaced 1-decimal-place DELC13 in s04ihy.txt (20020509WHPOSIOSA)
             with 2-decimal-place DELC13 from:
             /usr/export/html-public/data/onetime/southern/s04/s04i/original
             20020401.102545_GERLACH_SO4I/20020401.102545_GERLACH_SO4I_whpo
             _so4i.txt
          2. Both QUALT1 and QUALT2 set to QF value given in original data file.
          3. Replaced all "1"s in QUALT2 with QUALT1 flags.
             Checked that non-1 values in QUALT2 are equal to the corresponding 
             QUALT1 flags in the original bottle file. Only dicrepancy was 
             Station 2, Cast 2, Sample 24 where original DELHE3 QUALT1 flag was 
             5 whereas original QUALT2 flag was 9. Changed new bottle file to 
             correspond with with original.
          4. Made new exchange file for Bottle data.
          5. Checked new bottle file with Java Ocean Atlas.
          
08/28/03  Anderson     CTD/BTL/SUM     Final Data Submitted, online  
          Merged final data files into online hyd file 
            S04I event log by Sarilee Anderson (132.239.114.244/xebec.ucsd.edu) 
          Expocode: 320696_3
            SUM, CTD, Bottle: (ctdprs, ctdtmp, ctdsal, ctdoxy, theta, salnty, 
            oxygen, silcat, nitrat, nitrit, phspht, cfc-11, cfc-12, helium, 
            delhe3, delc14, delc13, tcarbn, alkali, pco2, delher, c14err, 
            qualt1, qualt2) 
          ODF submitted final data files for the bottle, ctd, and .sum data. I 
            merged values and QUALT flags from the online file into the new 
            final bottle file. Made new exchange and netcdf files. Put all files 
            online and sent notes to Jerry.

          Notes on the s04i remerge:   Aug. 27, 2003

          Copied the QUALT1 flags to the QUALT2 flags in the ODF final data 
            file 320696_3.sea found in 
            s04/s04i/original/ODF_FINAL_2003_S04I/s4ihyd.
          Merged CFC-11, CFC-12, HELIUMN, DELHE3, DELHER, DELC14, 14ERR, 
            DELC13, TACRBN, ALKALI, and PCO2 and their corresponding QUALT1 and 
            QUALT2 flags from the online file 20030312WHPOSIODM into the ODF 
            final data file 320696_3.sea.
          I did not merge REVPRS and REVTMP because the values were all -9.0.
          Checked the .sum file and made some minor column adjustments.
          The ctd files (s4ictd.zip) found in the ODF_FINAL_2003_S04I directory 
            were formatted correctly, renamed them from 00101.ctd to 
            s04i0001.wct, ect., and made a new zip file, s04ict.zip.

09/02/03  Kappa        DOC             Cruise Documentation Updated
          Added ODF "Final Cruise Report"
          Expanded these Data Processing Notes
 
09/09/03  Coartney     CrsRpt          New PDF and text docs online

04/28/06  Kozyr        CrsRpt          OK to add to online cruise report 
          Actually it is a very good idea to include CDIAC NDPs (Numeric Data 
          Packages) that describe methods and instrumentation of CO2-related 
          measurements with the related data files in WHPO/CCHDO database. I 
          would be happy to see that.

11/02/06  Swift        CFCs            remerge Warner's DQE'd CFCs 
          It was decided at today's CCHDO meeting to merge or remerge CFCs for 
          all WHP cruises in Mark Warner's CFC DQE file (Southern Ocean WHO 
          lines).  This will assure all that the CFCs for these cruises are 
          indeed updated as intended.  Danie and Sarilee will attend to this 
          promptly.  Danie will see that the sections of greatest urgency to 
          Lynne receive top priority.

          The list of cruises in Mark's file was as follows:
          
          A21:          EXPOCODE: 06MT11_5
          A23:          EXPOCODE: 74JC10_1
          I06S:         EXPOCODE: 35MFCIVA_1
          MARGINEX:     EXPOCODE: 09AR9604_1
          S03_S04I:     EXPOCODE: 09AR9404_1
          S04A:         EXPOCODE: 06AQANTIII_4
          S04I:         EXPOCODE: 320696_3
          S04P:         EXPOCODE: 90KDIOFFE6_1
          SR04A_A12:    EXPOCODE: 06AQANTX_4
          SR04_ANTXV4:  EXPOCODE: 06ANT15_4

          It may be that the CFCs for the following cruises from the list above 
          have already been updated:
          
          >   sr04antxv4
          >   s04p
          >   a23
          >   a21

          But, to be certain, the CCHDO will update them as well.

          As far as why these cruises did not get updated with Mark's DQE'd 
          CFCs, we have no idea.  Sorry.  All of the other ocean basins' CFCs 
          were updated years ago.

07/24/13  Kappa        CrsRpt          Updated pdf and text versions online
          • Chief Scientist changed from James Swift to Thomas Witworth on web 
            site, as per James Swift
          • Note added to table 1: "The LADCP was lost during a test, therefore 
            no LADCP data are reported for this cruise."
          • Data Processing notes updated/expanded
          • New test and pdf versions of the cruise report added to online 
            website
          • Old cruise reports moved to "original" directory.

