                      WOCE section     SR03
                      ExpoCode         09AR9101_1
                      Chief Scientist  STEVE RINTOUL CSIRO
                      Ship             RSV Aurora Australis
                      Ports of Call    Macquarie Island
                      Cruise Dates     September 25 to October 27 1991


GENERAL

Marine science cruise AU9101, the first completion of the WOCE SR3 
transect, was conducted aboard the Australian icebreaker RSV Aurora 
Australis from September to October 1991. The original plan was to carry 
out the transect from south to north, however following a stop at Macquarie 
Island the ship had to return to Tasmania for major CTD winch repairs. The 
transect was then commenced from north to south, skipping some stations due 
to bad weather. These stations were occupied on the return passage north.



PART 1: CTD PROCESSING NOTES FOR AU9101

D.J. Vaudrey
CSIRO Division of Oceanography
Hobart


Casts were carried out using the Australian Antarctic Division's NBIS Mark 
IIIB CTD serial 1193. The CTD was mounted in a 24 bottle rosette frame with 
10 l Niskin bottles, all supplied by the CFC group from NOAA PMEL. A pre-
cruise temperature sensor calibration, by the CSIRO Division of 
Oceanography Calibration Facility, was applied to the CTD temperature data. 
Pre-transect winch trails were carried out using other CTD units. Data from 
these casts, stations 1-5, were not processed due to unexplained hardware 
problems. Stations 6 and 7 were respectively the down and upcast of a 
shallow cast to 125 dbar; file problems occurred and these data were lost. 
Station 8 was the first full depth cast, carried out at the same site as 
station 6. One of the CTD's with hardware problems was trialed during 
station 21 with little success - temperature data only were processed for 
this station. No CTD dissolved oxygen data was obtained as the only working 
CTD could not be fitted with an oxygen sensor.

CTD data were logged on a single Hewlett Packard 286 PC using an early 
version of the NBIS Acquisition software. Neither audio nor direct digital 
recording were available for backup. Files were transferred to the ship's 
VAX, and archived daily to magnetic optical disk using VMS backup. The CTD 
PC had to be rebooted after each file transfer to the VAX, and the PC time 
was not always reset correctly. As a result incorrect times were often 
logged in the CTD file headers. These times were corrected later during 
data processing by checking the ship's underway data.

Two different NBIS rosette pylons were used throughout the cruise, both 
giving a variety of misfire problems. Various power failures, winch and 
trolley problems also caused delays. 


STATION LIST

1.  Winch test station. Incorrect pressure factor applied to logging 
    software and CTD hit the bottom. No apparent damage. Winch spooling 
    problems. Not calibrated due to hardware problem with conductivity.
2.  Winch trials. Appears to be a major problem with winch drum. Appears 
    as if cheek plates cracked away from drum. Not calibrated due to 
    hardware problem with conductivity.
3.  Winch trials. Numerous stops on upcast in attempt to get wire 
    spooled. Not calibrated due to hardware problem with conductivity.
4.  Winch trials. Numerous stops on upcast in attempt to get wire 
    spooled. Not calibrated due to hardware problem with conductivity.
5.  New cable spooled onto drum prior to this cast. Spooling not perfect. 
    Not calibrated due to hardware problem with conductivity.
6.  Shallow biology cast. Files scrambled. Could not be deciphered. First 
    cast with unit 1193. Not processed.
7.  Logged upcast of station 6. Not processed.
8.  First full station. Same site as station 6. Apparent misfire at position 
    1. Fired twice. Ramp indicated 25 successful fires. Vent on bottle 
    #23 not tight.
9.  Problem with deployment. Overhead gantry jammed. Logging stopped 
    after 20 minutes and restarted 20 minutes later.
10. Bottles 5 and 6 indicated misfires but ramp position indicated 
    successful firings. 200 metre biology cast.
11. Winch power lost at about 400 dbar on downcast. 50 minute delay. CTD 
    raised to above failure depth before recommencing downcast. Bottle 24 
    did not close. Misfire at position 15.
12. Problem with winch at 757 dbar on downcast. About 10 minutes lost. No 
    misfires.
13. Bottle #17 air vent not done up.
14. Misfire at bottle 5. Bottle 24 did not close.
15. No apparent problems.
16. No apparent problems. Bottom bottle fired 50 m above bottom due to 
    very rugged bottom. Misfire on position 24. Refired and got confirmation.
17. Station not carried out fully as too rough. No bottles sampled.
18. "Short" misfire on #13, but appears to have fired.
19. CTD cable jumped off sheave. Station aborted. Retermination of CTD 
    wire.
20. Retry of station 19. Some modifications to block to stop wire jumping 
    out were carried out prior to this station.
21. Two misfires at position 9 and 11. Used CTD 1013 as trial but still 
    problems with conductivity hysteresis.. Cause unknown. Able to 
    calibrate temperature only. Not archived.
22. Niskins relablled to swap deep and shallow sets of 12. a number of 
    misfires on position 6, 18, 19, 20, 21 and 22. Only one not closed on 
    recovery. Most likely #6 from O/E returns.
23. Rosette pylon checked out before cast. Some changes made. Wire 
    spooling problems on upcast. Misfire indicated on #19 and 20. All 
    bottles closed. Heavy rolling during recovery. cTD most likely hit 
    ship. Green water in CTD court. Bottle #9 leaking.
24. Misfires indicated on #15, 18, 19, 20 and 21. One bottle empty at the 
    surface. Most likely #15.
25. Pylon changed prior to this cast. Spooling problems. a number of 
    short stops and reversals to cure spooling problems on the upcast.
26. Misfire on #9. Bottle not closed at surface. Not fired.
27. No apparent problems.
28. Two halts during upcast for spooling problems (@3200 dbar and 1300 
    dbar).
29. Misfire at #1 (repeated fire), misfire at #23 and 24.
30. Sensor cover not filled prior to this station. Some spooling 
    difficulties. Misfire on #16 and 23.
31. Misfires on #8, 9, 10, 11 and 23.
32. Rosette pylon changed prior to this cast. No apparent problems. #24 
    leaking through tap on recovery.
33. Misfire on #23. 1 bottle empty at surface.
34. Misfire indicated on #9. All bottles closed.
35. Misfire indicated on #1, 4, 6 and 7. One bottle open.
36. Test cast for CFC's.



CALIBRATION INFORMATION

Temperature coefficients
CTD                 calibration date  offset         slope  
------------------------------------------------------------
1193                September 1991   -1.0049e-03 C  1.0004
1013 (stn 21 only)  September 1991    3.5007e-03 C  0.99994



CONDUCTIVITY CELL FACTORS 

station    offset term     slope term      station dependent  n   standard
grouping                                   slope correction       deviation
-----------------------------------------------------------------------------
 8 to 15  -0.32931824e-01  0.10013949e-02  0.11493561e-07    169  0.32613e-02
16 to 22  -0.43591284e-01  0.10011636e-02  0.31668779e-07     85  0.28287e-02

(station 21 not calibrated for conductivity)
23 to 35   0.42793579e-02  0.99997440e-03  0.67473564e-08  229    0.20476e-02

n = number of stations

Standard deviation of salinity (bottle-CTD) residual after calibration=0.0031 (PSS78)



SURFACE PRESSURE OFFSET (INDIVIDUAL STATIONS)

station  pressure offset (dbar)    station  pressure offset (dbar)
-------  ----------------------    -------  ----------------------
   8             -3.30               24             -2.90
   9             -3.40               25             -2.60
  10             -3.30               26             -2.60
  11             -4.00               27             -2.30
  12             -3.10               28             -2.50
  13             -3.00               29             -2.30
  14             -3.20               30             -2.90
  15             -3.20               31             -2.80
  16             -2.80               32             -2.90
  17             -3.00               33             -2.80
  18             -3.20               34             -2.60
  20             -2.80               35             -2.80
  22             -2.20              
  23             -3.00        



MOORINGS AND DRIFTERS

7 ALACE floats, 1 current meter mooring and 1 pressure gauge mooring were 
deployed during the cruise, as follows:

Current meter mooring deployment
Site  deployment  bottom     latitude     longitude     current meter  nearest CTD
name  time (UTC)  depth (m)                             depths (m)     station no.
-----------------------------------------------------------------------------
SO1  12 Oct 1991  3570       50 42.90'S  143 22.90'E      570          18
                                                            820
                                                           1070
                                                           2070
                                                           3270


PRESSURE GAUGE MOORING DEPLOYMENT

site       deployment           bottom    latitude      longitude    nearest CTD
name       time (UTC)           depth (m)                            station no.
-----------------------------------------------------------------------------
Hobart91b  07:49, 08 Oct 1991   1043      44 06.83'S   146 14.03'E      35

ALACE float deployments
deployment  sn  deployment          latitude     longitude     nearest CTD
  number        time (UTC)                                     station no.
-----------------------------------------------------------------------------
    1       89  19:59, 10 Oct 1991  48 44.8'S    143 55.9'E      14
    2       25  22:25, 11 Oct 1991  50 39.9'S    143 17.0'E      18
    3       93  10:45, 22 Oct 1991  56 24.4'S    140 39.4'E      22
    4       91  19:53, 22 Oct 1991  54 39.5'S    141 29.7'E      21
    5       90  23:07, 23 Oct 1991  52 07.5'S    141 38.5'E      20
    6       88  18:05, 24 Oct 1991  49 53.10'S  143 23.49'E      16
    7       94  21:38, 25 Oct 1991  44 41.61'S  145 55.75'E      34



REFERENCES

Rintoul, S.R. and Bullister, J.L., 1999. A late winter hydrographic section 
   from Tasmania to Antarctica. Deep-Sea Research I, Vol. 46, pp1417-1454.





PART 2: CFC-11 AND CFC-12 MEASUREMENTS ON AU9101 (WOCE SR3) 

(Following discussion provided by John Bullister)
 
 
John Bullister
NOAA-PMEL 
Building #3                
7600 Sand Point Way, NE                   
Seattle, WA 98115   USA                         
Telephone: 206-526-6741  
FAX      : 206-526-6744
Internet:  bullister@pmel.noaa.gov


CRUISE A9101 CHLOROFLUOROCARBON (CFC) MEASUREMENTS

Specially designed 10 liter water sample bottles were used on the cruise to 
reduce CFC contamination.  These bottles have the same outer dimensions as 
standard 10 liter Niskin bottles, but use a modified end-cap design to 
minimize the contact of the water sample with the end-cap O-rings after 
closing.  The O-rings used in these water sample bottles were vacuum-baked 
prior to the first station.  Stainless steel springs covered with a nylon 
powder coat were substituted for the internal elastic tubing standardly 
used to close Niskin bottles.

Water samples for CFC analysis were usually the first samples collected 
from the 10 liter bottles. Care was taken to co-ordinate the sampling of 
CFCs with other samples to minimize the time between the initial opening of 
each bottle and the completion of sample drawing.  In most cases, dissolved 
oxygen and total CO2 were collected within several minutes of the initial 
opening of each bottle.  To minimize contact with air, the CFC samples were 
drawn directly through the stopcocks of the 10 liter bottles into 100 ml 
precision glass syringes equipped with 2-way metal stopcocks.  The syringes 
were immersed in a holding tank of clean surface seawater until analyses.

To reduce the possibility of contamination from high levels of CFCs 
frequently present in the air inside research vessels, the CFC 
extraction/analysis system and syringe holding tank were housed in a 
modified 20' laboratory van on the deck of the ship.

For air sampling, a ~100 meter length of 3/8" OD Dekaron tubing was run 
from the CFC lab van to the bow of the ship.  Air was sucked through this 
line into the CFC van using an Air Cadet pump.  The air was compressed in 
the pump, with the downstream pressure held at about 1.5 atm using a back-
pressure regulator.  A tee allowed a flow (~100 cc/min) of the compressed 
air to be directed to the gas sample valves, while the bulk flow of the air 
(>7 liter/minute) was vented through the back pressure regulator.

Concentrations of CFC-11 and CFC-12 in air samples, seawater and gas 
standards on the cruise were measured by shipboard electron capture gas 
chromatography (EC-GC), using techniques similiar to those described by 
Bullister and Weiss (1988).  For seawater analyses, a ~30-ml aliquot of
seawater from the glass syringe was transferred into the glass sparging 
chamber.  The dissolved CFCs in the seawater sample were extracted by 
passing a supply of CFC-free purge gas through the sparging chamber for a 
period of 4 minutes at ~70 cc/min.  Water vapor was removed from the purge 
gas while passing through a short tube of magnesium perchlorate dessicant.  
The sample gases were concentrated on a cold-trap consisting of a 3-inch 
section of 1/8-inch stainless steel tubing packed with Porapak C and 
Porapak T (60-80 mesh) immersed in a bath of isopropanol held at -20 
 C.  After 4 minutes of purging the seawater sample, the sparging 
chamber was closed and the trap isolated.  The trap was then heated to 100 
 C.  The sample gases held in the trap were then injected onto a 
precolumn (12 inches of 1/8-inch O.D.  stainless steel tubing packed with 
80-100 mesh Porasil C, held at 90  C), for the initial separation of 
the CFCs and other rapidly eluting gases from more slowly eluting 
compounds.  The CFCs then passed into the main analytical column (10 feet, 
1/8-inch stainless steel tubing packed with Porasil C 80-100 mesh, held at 
90  C), and then into the EC detector.

The CFC analytical system was calibrated frequently using standard gas of 
known CFC composition.  Gas sample loops of known volume were thoroughly 
flushed with standard gas and injected into the system.  The temperature 
and pressure was recorded so that the amount of gas injected could be 
calculated.  The procedures used to transfer the standard gas to the trap, 
precolumn, main chromatographic column and EC detector were similar to 
those used for analyzing water samples. Two sizes of gas sample loops were 
present in the analytical system. Multiple injections of these loop volumes 
could be done to allow the system to be calibrated over a relatively wide 
range of CFC concentrations.  Air samples and system blanks (injections of 
loops of CFC-free gas) were injected and analyzed in a similar manner.  The 
typical analysis time for a seawater, air, standard or blank sample was 
about 12 minutes.

Concentrations of CFC-11 and CFC-12 in air, seawater samples and gas 
standards are reported relative to the SIO93 calibration scale (Cunnold, 
et.  al., 1994).  CFC concentrations in air and standard gas are reported 
in units of mole fraction CFC in dry gas, and are typically in the parts-
per trillion (ppt) range.  Dissolved CFC concentrations are given in units 
of picomoles of CFC per kg seawater (pmol/kg).  CFC concentrations in air 
and seawater samples were determined by fitting their chromatographic peak 
areas to multi-point calibration curves, generated by injecting multiple 
sample loops of gas from a CFC working standard (PMEL cylinder 71489) into 
the analytical instrument.  The concentrations of CFC-11 and CFC-12 in this 
working standard were calibrated before and after the cruise versus a 
primary standard (36743) (Bullister, 1984).  No measurable drift in the 
concentrations of CFC-11 and CFC-12 in the working standard could be 
detected during this interval.  Full range calibration curves were run at 
intervals of ~3 days during the cruise.  Single injections of a fixed 
volume of standard gas at one atmosphere were run much more frequently (at 
intervals of 1 to 2 hours) to monitor short term changes in detector 
sensitivity.

Dissolved CFCs were detected throughout the section. The lowest (<0.01 
pmol/kg) CFC concentrations were measured in deep water (>2500 meters) on 
the northern end of the section, north of 47oS near Tasmania.  The low, but 
non-zero CFC-11 and CFC-12 concentrations observed in most of the samples 
from this region are generally consistent, with each other, and indicate 
very long time scales for ventialation of these waters. Because of the 
absence of CFC-free waters along the section, and the agreement of observed 
CFC-11 and CFC-12 concentrations at low levels, no blank corrections have 
been applied to the reported CFC-11 and CFC-12 data sets.

On this expedition, we estimate precisions (1 standard deviation)  of about 
1% or 0.005 pmol/kg (whichever is greater) for dissolved CFC-11 and 2% or 
0.005 pmol/kg (whichever is greater) for dissolved CFC-12 measurements (see 
listing of replicate samples given at the end of this report).

A number of water samples had clearly anomolous CFC-11 and/or CFC-12 
concentrations relative to adjacent samples.  These anomolous samples 
appeared to occur more or less randomly during the cruise, and were not 
clearly associated with other features in the water column (eg. elevated 
oxygen concentrations, salinity or temperature features, etc.).  This 
suggests that the high values were due to individual, isolated low-level 
CFC contamination events.  Measured concentrations for these samples are 
included in this report, but are give a quality flag of either 3 
(questionable measurement) or 4 (bad measurement).  A total ~12 analyses of 
CFC-11 were assigned a flag of 3 and ~12 analyses of CFC-12 were assigned a 
flag of 3. A total of ~9 analyses of CFC-11 were assigned a flag of 4 and 
~8 CFC-12 samples assigned a flag of 4.

CFC samples from test stations 1-7 are not included in this report.

In addition to the file of mean CFC concentrations, tables of the following 
are included in this report:

Table 1a. A9101 Replicate dissolved CFC-11 analyses
Table 1b. A9101 Replicate dissolved CFC-12 analyses
Table 2.  A9101 CFC air measurements
Table 3.  A9101 CFC air measurments interpolated to station locations

A value of -9.0 is used for missing values in the listings.


REFERENCES

Bullister, J.L., 1984.  Anthropogenic Chlorofluoromethanes as Tracers of 
   Ocean Circulation and Mixing Processes:  Measurement and Calibration 
   Techniques and Studies in the Greenland and Norwegian Seas. Ph.D. 
   dissertation, Univ. Calif. San Diego, 172 pp.
Bullister, J.L. and R.F. Weiss, 1988. Determination of CCl3F and CCl2F2 in 
   seawater and air. Deep-Sea Research, 35 (5), 839-853.
Cunnold, D.M., P.J. Fraser, R.F. Weiss, R.G. Prinn, P.G. Simmonds, B.R. 
   Miller,F.N. Alyea,  and A.J.Crawford, 1994. Global trends and annual 
   releases of CCl3F and CCl2F2 estimated from ALE/GAGE and other 
   measurements from July 1978 to June 1991.  J.  Geophys. Res., 99, 1107-
   1126.


Table 1a:  AU9101 Replicate dissolved CFC-11 analyses

STATION   SAMP      F11      F11  
 NUMBER    NO.     pM/kg    Stdev 
---------------------------------
  15        1      0.019    0.001 
  15        4      0.031    0.004 
  18        2      0.023    0.001 
  20       21      5.114    0.019 
  20       23      4.978    0.191 
  23       10      0.048    0.002 
  24       20      6.490    0.034 
  27       23      5.930    0.008 
  29       10      0.047    0.002 
  29       23      5.715    0.007 
  31       14      1.117    0.028 
  33       23      4.233    0.033 
  35        5      2.047    0.049 


Table 1b:  A9101 Replicate dissolved CFC-12 analyses

STATION   SAMP      F12      F12  
 NUMBER    NO.     pM/kg    Stdev 
---------------------------------
  15       1       0.008    0.001 
  15       4       0.015    0.001 
  18       2       0.013    0.004 
  20      21       2.453    0.006 
  20      23       2.462    0.031 
  23      10       0.032    0.000 
  24      20       2.955    0.021 
  27      23       2.767    0.004 
  29      10       0.025    0.000 
  29      23       2.725    0.013 
  31      14       0.550    0.018 
  33      23       2.086    0.021 
  35       5       1.031    0.037 


Table 2:  A9101 CFC Air Measurements

Leg 1
             Time                             F11     F12  
 Date       (hhmm)   Latitude    Longitude    PPT     PPT  
----------------------------------------------------------
30 Sep 91    1016   53 12.5 S   157 04.6 E   252.7   490.4 
30 Sep 91    1047   53 12.5 S   157 04.6 E   256.1   495.7 
30 Sep 91    1059   53 12.5 S   157 04.6 E   255.2   487.5 
30 Sep 91    1112   53 12.5 S   157 04.6 E   257.0   495.4 
10 Oct 91    1851   48 44.0 S   143 55.0 E   256.4   491.2 
10 Oct 91    1905   48 44.0 S   143 55.0 E   257.6   494.4 
10 Oct 91    1919   48 44.0 S   143 55.0 E   255.7   495.4 
14 Oct 91    1940   54 32.0 S   142 21.0 E   255.4   484.8 
14 Oct 91    1953   54 32.0 S   142 21.0 E   255.7   492.0 
14 Oct 91    2010   54 32.0 S   142 21.0 E   255.0   486.6 
18 Oct 91    0026   63 25.0 S   137 49.0 E   257.4   494.8 
18 Oct 91    0039   63 25.0 S   137 49.0 E   255.9   492.0 
18 Oct 91    0051   63 25.0 S   137 49.0 E   256.6   494.4 
18 Oct 91    0107   63 25.0 S   137 49.0 E   256.0   491.7 
22 Oct 91    0350   57 15.0 S   140 17.0 E   254.5   490.4 
22 Oct 91    0403   57 15.0 S   140 17.0 E   255.6   491.7 
22 Oct 91    0416   57 15.0 S   140 17.0 E   255.3   488.6 
22 Oct 91    0430   57 15.0 S   140 17.0 E   253.6   488.0 
24 Oct 91    1828   49 51.0 S   143 24.0 E   256.6   492.9 
24 Oct 91    1843   49 51.0 S   143 24.0 E   256.7   493.0 
24 Oct 91    1857   49 51.0 S   143 24.0 E   255.4   488.5 


Table 3:  A9101 CFC Air values (interpolated to station locations)
 
STATION                                              F11     F12  
 NUMBER         Latitude    Longitude     Date       PPT     PPT  
-----------------------------------------------------------------
     1         44 54.5 S   149 15.0 E   26 Aug 91   262.0   485.0 
     2         48 14.4 S   152 34.7 E   27 Aug 91   262.0   485.0 
     3         44 17.6 S   148 26.5 E    4 Oct 91   255.8   491.9 
     4         44 18.0 S   148 26.1 E    4 Oct 91   255.8   491.9 
     5         44 08.1 S   148 12.9 E    7 Oct 91   255.8   492.9 
     6         45 11.0 S   145 42.2 E    8 Oct 91   255.9   490.7 
     7         45 11.0 S   145 42.2 E    8 Oct 91   255.9   490.7 
     8         45 11.1 S   145 43.8 E    8 Oct 91   255.9   490.7 
     9         45 49.7 S   145 25.6 E    9 Oct 91   255.9   490.7 
    10         46 28.1 S   145 05.1 E    9 Oct 91   255.9   490.7 
    11         46 27.3 S   145 04.9 E    9 Oct 91   255.9   490.7 
    12         47 14.4 S   144 45.6 E    9 Oct 91   255.9   490.7 
    13         47 59.4 S   144 22.0 E   10 Oct 91   255.9   490.7 
    14         48 44.8 S   143 55.6 E   10 Oct 91   255.9   490.7 
    15         49 12.8 S   143 38.9 E   10 Oct 91   255.9   490.7 
    16         49 44.5 S   143 26.8 E   11 Oct 91   255.9   490.7 
    17         50 12.9 S   143 11.2 E   11 Oct 91   255.9   490.7 
    18         50 39.7 S   143 16.2 E   11 Oct 91   255.9   490.7 
    19         50 39.7 S   143 16.2 E   12 Oct 91   255.9   490.7 
    20         51 51.4 S   142 36.5 E   13 Oct 91   255.9   490.7 
    21         54 39.8 S   141 22.9 E   15 Oct 91   255.7   490.7 
    22         56 27.8 S   140 37.7 E   15 Oct 91   256.0   491.6 
    23         58 08.2 S   139 50.7 E   16 Oct 91   255.0   488.9 
    24         59 37.1 S   139 09.9 E   16 Oct 91   255.6   491.5 
    25         61 46.9 S   138 07.2 E   17 Oct 91   255.6   491.5 
    26         64 53.3 S   136 23.4 E   19 Oct 91   255.6   491.5 
    27         63 36.1 S   137 00.3 E   20 Oct 91   255.6   491.5 
    28         60 40.7 S   138 40.5 E   21 Oct 91   255.6   491.5 
    29         57 15.3 S   140 16.8 E   22 Oct 91   255.6   491.5 
    30         54 06.3 S   141 40.2 E   22 Oct 91   255.4   490.5 
    31         53 25.2 S   141 56.9 E   23 Oct 91   255.4   490.5 
    32         51 14.2 S   142 55.9 E   24 Oct 91   255.4   490.5 
    33         50 12.1 S   143 12.1 E   24 Oct 91   255.4   490.5 
    34         44 42.3 S   145 55.9 E   25 Oct 91   255.4   490.5 
    35         44 05.9 S   146 14.8 E   26 Oct 91   255.4   490.5 
    36         43 54.5 S   148 03.4 E   26 Oct 91   255.4   490.5 




PART 3:    CONVERSION OF DATA TO WOCE FORMAT

Mark Rosenberg
Antarctic CRC
Hobart


CTD 2 DBAR-AVERAGED DATA FILES (*.CTD)

* CTD 2 dbar-averaged file format is as per the WOCE manual, except that 
  measurements are centered on even pressure bins (with first value at 2 
  dbar).
* CTD temperature and salinity are reported to the third decimal place 
  only. 


HYDROLOGY DATA FILE (A9101.SEA)

* CTD upcast burst data were only available for pressure. CTD temperature, 
  salinity and theta values are from equivalent pressures in the downcast 
  2 dbar CTD data.
* Hydrology data file format is as per the WOCE manual.
* The total value of nitrate+nitrite only is listed. 
* Silicate and nitrate+nitrite are reported to the first decimal place 
  only. 
* CTD temperature (including theta), CTD salinity and bottle salinity are 
  all reported to the third decimal place only. 
* Raw CTD pressure values are not reported.
* SAMPNO is equal to the rosette position of the Niskin bottle.
* Bottle oxygen data where no equivalent CTD data were available for 
  conversion of units are not reported.
* Salinity samples rejected for conductivity calibration are not flagged 
  in the .sea file.


CONVERSION OF UNITS FOR BOTTLE DISSOLVED OXYGEN AND NUTRIENTS

DISSOLVED OXYGEN

All Niskin bottle dissolved oxygen concentration values have been converted 
from volumetric units µmol/l to gravimetric units µmol/kg, as follows. 
Concentration Ck in µmol/kg is given by

	Ck  =  1000 Cl / rho(theta,s,0)            

where Cl is the concentration in µmol/l, 1000 is a conversion factor, and 
rho(theta,s,0) is the potential density at zero pressure and at the 
potential temperature theta, where potential temperature is given by

	theta = theta(T,s,p)            	

for the in situ temperature T, salinity s and pressure p values at which 
the Niskin bottle was fired. Note that T and s are from equivalent 
pressures in the downcast 2 dbar CTD data, as mentioned above.


NUTRIENTS

For the WOCE format files, all Niskin bottle nutrient concentration values 
have been converted from volumetric units µmol/l to gravimetric units 
µmol/kg using

	Ck  =  1000 Cl/rho(Tl,s,0)            

where 1000 is a conversion factor, and rho(Tl,s,0) is the water density in 
the hydrology laboratory at the laboratory temperature Tl and at zero 
pressure. No laboratory temperature values were recorded during the cruise 
- a estimated value Tl = 22oC has been used for all the data. CTD salinity 
values are used for s, as per the oxygen data. For samples where no CTD 
data were available, bottle salinities are used for s.


STATION INFORMATION FILES

* File format is as per the WOCE manual.
* All depths are calculated using a uniform speed of sound through the 
  water column of 1498 ms-1. Reported depths are as measured from the water 
  surface
* An altimeter attached to the base of the rosette frame (approximately at 
  the same vertical position as the CTD sensors) measures the elevation (or 
  height above the bottom) in metres. The elevation value at each station is 
  recorded manually from the CTD data stream display at the bottom of each 
  CTD downcast. Motion of the ship due to waves can cause an error in these 
  manually recorded values of up to _3 m.
* Lineout (i.e. meter wheel readings of the CTD winch) were unavailable.

