A.      Cruise Narrative P16C

A.1.    Highlights

                       WHP Cruise Summary Information

                      WOCE Line  P16C
                       EXPOCODE  31WTTUNES_3
               Chief Scientist:  Lynne Talley 
                                 Scripps Institution of Oceanography
                                 University of California San Diego
                                 9500 Gilman Drive
                                 La Jolla  CA  92093-0230
                                 Phone:  619-534-6610
                                 Fax:    619-534-9820
                                 e-mail: ltalley@ucsd.edu
                           Ship  R/V Thomas Washington
             Number of Stations  148
                                            18 53'N
          Geographic boundaries  150 28'W            15539'W
                                           17 30'S
                Floats deployed  12 ALACE floats
              Drifters deployed  7 surface drifters
 Moorings deployed or recovered  0
                  Ports of Call  Papeete, Tahiti to Honolulu, Hawaii
                   Cruise Dates  August 31 to October 1, 1991

WHP Cruise and Data Information

A.      Cruise Narrative
A.1.      Highlights
A.2.      Cruise Summary
A.3.      List of Principal Investigators
A.4.      Scientific programme and methods
A.5.      Major problems encountered on the cruise
A.6.      List of Cruise Participants
B.      Description of measurement techniques and calibrations
B.1.      Navigation and bathymetry
B.2.      Acoustic Doppler Current Profiler
B.3.      Thermosalinograph and Underway Dissolved Gases
B.4       XBT's
B.5       Meteorological Observations
C.      Hydrographic measurements
C.1.      CTD
C.1.a       CTD temperature
C.1.b       CTD pressure
C.1.c       CTD conductivity
C.1.d       CTD oxygen
C.1.e       CTD individual station comments
C.2.      Gerard Bottles
C.3.      Salinity
C.4.      Oxygen
C.5.      Nutrients
C.6.      Carbon Systems 
C.7.      Chlorofluorocarbons
C.8.      Tritium 
C.9.      Shallow Helium-3 
C.10.     Deep helium-3 
D.      Acknowledgments
E.      References
F.      Bottle data comments and flagging
G.      Data Quality Evaulation
G.1       Hydrographic Data
G.2       CTD data
G.3       Large volume data
G.4       AMS 14C Samples
G.5       CFC Data
H       Responses to data quality evaluations
H.1       Hydrography
H.2       Response to CTD DQE (L.Talley)
H.2.a     Response to CTD DQE (M. Cook)
I       Data Processing Notes


A.2.   Cruise Summary

A.2.a. Cruise Track

R/V T. Washington departed Papeete, Tahiti for its third
consecutive WOCE leg on Aug. 31, 1991.  Stations were numbered
consecutively from the beginning of the R/V Washington work on
P17C, starting off the coast of California in May, 1991.  The first
station on Leg 3 (P16C) was numbered 221 and was a reoccupation of
the last station on Leg 2 (P16S), which was numbered 220.

All stations were to the bottom and consisted of a rosette/CTD
cast.  Basic station spacing was 30 nm, closing to 20 nm for the
large (36 10-liter bottle) rosette between 3S and 3N. A small
rosette, with 11 1.7-liter bottles and a different CTD (WHOI's CTD
9), was alternated with the large rosette stations between 3S and
3N, to obtain CTD station spacing of 10 nm.

In Fig. A.2.1, +'s are standard CTD/36-bottle rosette stations,
triangles are CTD/36-bottle rosette stations with large volume
sampling, and asterisks are CTD/11-bottle rosette stations with
mounted ADCP (non-WOCE measurement).

On 25 days a separate JGOFS bio-optics station was made within
several hours of noon (Fig. A.2.2). These stations extended to 200 m.

A.2.b. TOTAL NUMBER OF STATIONS AND STATION TYPE 
       (Fig. A.2.3 and A.2.4)

       106  CTD/36-bottle rosette stations
        18  CTD/11-bottle rosette/LADCP stations (non-WOCE)
         8  Large volume sampling (Gerard barrel) stations
        25  200-meter bio-optics stations (JGOFS)

Sampling was done primarily with a 36-place double-ring rosette
with mounted CTD (WHOI CTD 10), transmissometer, and pinger.  CTD
data consisted of pressure, temperature, conductivity, oxygen and
transmissometry.  All profiles were full water column depth.  Water
samples were collected for analyses of salt, oxygen, silica,
phosphate, nitrate and nitrite on all stations and of CFC-11, CFC-
12, helium-3, helium-4, tritium, AMS C14, alkalinity, and total
dissolved inorganic carbon on selected stations.  Water sample
depths are shown in Fig. A.2.3.

A small rosette with 11 1.7 liter bottles and WHOI CTD 9, a pinger
and an Acoustic Doppler Current Profiler was used on alternate
stations between 3S and 3N, to produce a station spacing of 10 nm.
CTD data consisted of pressure, temperature, conductivity and
oxygen.  Water sampling was limited to salinity and oxygen for
calibration of the CTD.  All profiles were full water column depth.
Water sample depths are included in Fig. A.2.3.

Large-volume sampling was made with use of 270-liter Gerard barrels
for analyses of C14, salinity, oxygen and silica on 8 stations.
All profiles consisted of at least 2 9 barrel casts and covered the
full water column.  Water sample depths are shown in Fig. A.2.4.

Bio-optics stations consisted of a profile using a spectral
radiometer package (MER) which measured pressure, temperature,
conductivity, fluorescence, transmission, downwelling irradiance,
upwelling radiance and photosynthetically-available radiation.  A
water sample was collected at 200 m and a separate bucket sample at
the surface; both were filtered to be run later for chlorophyll,
pigments and absorption spectra.

Underway measurements included Acoustic Doppler Current Profiling,
pCO2, pN2O, and surface temperature.  Underway bathymetry was
collected every 2 minutes from the center beam output of the
Washington's Seabeam system and merged with GPS navigation.

A.2.c. FLOATS AND DRIFTERS DEPLOYED (Fig. A.2.5)

       12 ALACE floats deployed (plus)
        7 surface drifters deployed (asterisk)

A.2.d. MOORING DEPLOYMENTS OR RECOVERIES

None

A.2.e. INTERLABORATORY COMPARISONS

No interlaboratory comparisons were made per se on P16C, but water
sample results were compared with preliminary data acquired on
P16S, with final data from the Oceanographer Transport of
Equatorial Waters (TEW) cruise at 12S and from the Moana Wave
cruise at 10N. Comparisons of P16C salinity, oxygen, silica and
nitrate with data from these three cruises are shown in Figs.

A.2.6-8.  Phosphates from all three comparisons are shown in Fig.

A.2.9. No data from P16C were excluded, despite some obvious errors.

The P16S cruise, with chief scientist J. Swift of SIO, immediately
preceded P16C on the same vessel.  CTD and salinity/oxygen/nutrient
analyses were carried out by SIO's Oceanographic Data Facility.  In
an attempt to produce data sets from P16S and P16C which are
compatible without further adjustments by the data user, the same
nutrient standards and same nutrient autoanalyzer were used on the
two cruises (as well as on the preceding P17C/S).  Different
standard sea waters (SSW's) were used for salinity measurements on
the two legs: P114 on Leg 2 for stations 124-140, P108 on Leg 2 for
stas 141-220, and P114 on Leg 3.   P108 and P114 were checked
against each other at the beginning of P16C and P114 was found to
be about 0.0015 psu higher than P108. A comparison of both SSW's
against a common standard will be made sometime in the next year
(Mantyla, personal communication).  ODF used traditional Winkler
titration for oxygen and WHOI used a new automated titration system
with the same chemistry and measurement on an aliquot drawn from
the sample bottle.

Fig. A.2.6 shows properties from the last five stations of P16S and
the first five stations of P16C. Stations 220 (P16S) and 221 (P16C)
were at the same location.  Although the rest of the stations are
not co-located, agreement of the properties (such as silica)
indicates that the same deep water was sampled in both groups of
stations.  In Fig. A.2.6, it is seen that the salinities from P16C
are about 0.003-0.004 psu higher than from P16S and noisier; about
half of the offset is accounted for by the difference in SSW.
Oxygen, silica and phosphate agree well.  Nitrate is higher on P16C
than on P16S by about .6 umol/l (1.7%).  Post-cruise processing of
the nutrient values may change the relative offsets of the two data
sets.

The TEW cruise, with principal investigator Stan Hayes, occurred in
summer, 1987, on the NOAA ship Oceanographer.  The cruise track was
roughly zonal, along 12S.  Technical support was from NOAA/PMEL
(CTD, salinity, freon), Duke (nutrients), and Bigelow Laboratory/U.
Washington (oxygen). A data report is now available (Mangum et al.,
1991).  This is considered a "pre-WOCE" cruise and will not be
duplicated in WOCE. Figs.  A.2.7 and A.2.9 show P16C salinity 0.004
psu lower, oxygen 0.05 ml/l higher (1.3%), silica in the same
range, nitrate 0.9 umol/l higher (2.5%), and phosphate in the same
range.  (Units of ml/l were used for oxygen because the TEW oxygen
data available were in these units.)

A zonal section at 10N on R/V Moana Wave, with principal
investigator John Toole, used technical support from WHOI for
salinity, oxygen and CTD, and from Oregon State University for
nutrients.  This cruise is also considered "pre-WOCE" and will not
be duplicated.  A data report is currently being printed.  Fig.
A.2.8 and A.2.9 show P16C salinity and oxygen in the same range,
silica 4 umol/l higher (3%), nitrate 0.8 umol/l lower (2.3%), and
phosphate 0.1 umol/l lower (4%).

Thus the P16S and P16C data sets are indeed closer to each other in
more parameters than is P16C with either TEW or the Moana Wave
cruise.  Also, with the exception of the high Moana Wave
phosphates, the differences are almost within the WHP
specifications. Scatter in the TEW data is the highest, in all
parameters except possibly silica.  However, given the expectation
and planning to make sure that the P16S and P16C data sets would be
as compatible as if the same technical groups had produced both, it
was hoped that the differences in salinity and nitrate would have
been smaller.  If due to differences in techniques, it is hoped
that these will be resolved prior to the next set of US WOCE
cruises in 1992.


A.3.    LIST OF PRINCIPAL INVESTIGATORS

John Bullister    CFC                    NOAA/PMEL    johnb@noaa.pmel.gov
Harmon Craig      deep helium-3          SIO          hcraig@ucsd.edu
                   (> 1200 meters)        
Russ Davis        ALACE floats           SIO          redavis.ucsd.edu
Eric Firing       ADCP                   U.Hawaii     efiring@soest.hawaii.edu
Wilf Gardner      Transmissometer        TAMU         richardson@astra.tamu.edu
Louis Gordon      Nutrients support      OSU          lgordon@oce.orst.edu
Catherine Goyet   Carbon Dioxide         WHOI
William Jenkins   Shallow Helium-3       WHOI         wjj@burford.whoi.edu
                   and tritium         
Charles Keeling   Carbon Dioxide         SIO          pguenther@ucsd.edu
Robert Key        Large volume           Princeton    key@wiggler.princeton.edu
Carbon-14 
John Marra        Bio-optics             LDEO         marra@ldeo.columbia.edu
Peter Niiler      Surface drifters       SIO          pniiler@ucsd.edu
Paul Quay         AMS Carbon-14          U.Washington pdquay@u.washington.edu
Stuart Smith      Bathymetry             SIO          ssmith@ucsd.edu
Lynne Talley      CTD/hydrography        SIO          ltalley@ucsd.edu
Lynne Talley      Underway temperature   SIO          ltalley@ucsd.edu
John Toole        CTD/hydro support      WHOI         jtoole@whoi.edu
Ray Weiss         underway pCO2 and pN2O SIO          rfweiss@ucsd.edu

      LDEO:          Lamont-Doherty Earth Observatory
                     Palisades  NY  10964
      NOAA/PMEL:     National Oceanic and Atmospheric Administration
                     Pacific Marine Environmental Laboratory.
      OSU:           Oregon State University 
                     College of Oceanic and Atmospheric Sciences
                     Corvallis  OR  97331-5503
      Princeton U.:  Princeton University
                     Geology Dept., Guyot Hall
                     Princeton  NJ  08544
      SIO:           Scripps Institution of Oceanography
                     UCSD
                     La Jolla  CA  92093 USA
      SIO/MTG:       SIO Marine Technical Group
                     UCSD
                     La Jolla  CA  92093-0214 
      SIO/ODF:       SIO Oceanographic Data Facility
                     UCSD
                     La Jolla  CA  92093-0214 
      TAMU:          Texas A&M University
                     College Station  TX  77843
      U. Hawaii:     University of Hawaii
                     1000 Pope Rd.
                     Honolulu  HI  96822
      U.Washington:  University of Washington
                     Seattle, WA 98195
      WHOI:          Woods Hole Oceanographic Institution
                     Woods Hole  MA  02543


A.4.     SCIENTIFIC PROGRAMME AND METHODS

A.4.a.   NARRATIVE

A.4.a.1. UPPER OCEAN STRUCTURE

Data from the upper 1000 meters extends the large data set
collected in 1979-1980 between Tahiti and Hawaii. The principal
features on P16C in the surface dynamic height relative to 1000
meters are a very broad South Equatorial Current, from 20S to 2
30'S, the signature of the westward Equatorial Current, a weak
eastward flow at 2N, and then a very strong North Equatorial
Countercurrent and pronounced North Equatorial Current.  The
preliminary dynamic height difference across the NECC yields an
approximate velocity of 85 cm/sec which is about twice what was
usually reported for the shuttle (e.g. Wyrtki and Kilonsky, 1984;
Taft and Kovala, 1981).  The NEC is of course broader and
preliminary dynamic height yields an average of about 15-20 cm/sec.

The upper ocean potential density section shows the familiar
Equatorial Undercurrent, Equatorial Intermediate Current and North
and South Subsurface Countercurrents (Tsuchiya Jets).  The latter
are pycnostads centered at 26.5-26.6 sigma theta.  Just poleward of
and slightly deeper than these are another pair of pycnostads,
centered at 26.8-26.9 sigma theta, and located between 5-10N and
5-10S.  As far as we know, these have not been pointed out before
although they are apparent in sections in the data reports from the
Norpax shuttle.

The salinity structure of the upper 1000 meters is well-described
by the Norpax shuttle.  The southern salinity maximum of the upper
200 meters surfaces between 13 30'S and 15S and extends northward
above the Tsuchiya jet, where it is extremely thin and centered at
24.0-25.0 sigma theta.  The northern salinity and southern salinity
maxima meet between 7 and 8N.  The North Pacific Intermediate Water
is found at the northern end of the section and terminates abruptly
and spectacularly at 16 30'N where it is chopped off from below by
higher salinity water from the south and then disappears at the
next station to the south.  The Antarctic Intermediate Water is
weakly present up to 14 30'N.

The lowest bottle oxygen measured in the oxygen minimum was 0.16
ml/l, at 320 meters at 9 30'N, the northern edge of the NECC.

A.4.a.2. INTERMEDIATE DEPTH OXYGEN AND NUTRIENT STRUCTURE 
         (1000- 3500 meters)

Interesting geostrophic shear was found at 2000-3500 m between 9S
and the southern end of the section at 17 30'S in the form of a
bowl in isopycnals, with the lowest point at 14-15S.  A similar
phenomenon is found north of the equator, with the bowl at 2000-
3500 m between 3N and the northern end of the section at Hawaii
(18N) and the lowest point at 9-10S.  There may be some interesting
stacked jets at the equator, but further work with the data will be
necessary to confirm them.  Both the preliminary geostrophic shear
and lowered ADCP showed greatly decreased vertical wavelength at
the equator compared with just a few degrees on either side.

The bowl-shaped isopycnals were accompanied by very clear property
signatures, particularly in oxygen for which we had continuous CTD
profiles.  Oxygen profiles centered at 12S below about 1500 meters
developed a layered structure, with one pronounced layer of roughly
uniform oxygen roughly between 2000 and 3000 meters.  At 12S, this
developed into a slight oxygen minimum. North of the equator, in a
band from about 2N to 10N, a weaker version of the oxygen layer was
also found. A positive thermal anomaly was also associated with the
oxygen layer with maximum anomalies at 12S and 8N (G. Johnson,
personal communication).  Johnson has also found silica anomalies
on the relevant isotherms at the same locations.  The location of
the layer and its lateral center is therefore on the equatorward
side of the isopycnal bowl found in each hemisphere.  The low
oxygen in the layer suggests an eastern source.  This depth range
is of course that expected for the well-defined helium plumes which
originate on the East Pacific Rise (Lupton and Craig, 1981); the
cause of the focusing of the helium signatures into distinct plumes
north and south of the equator is unknown, although hydrothermal
forcing has been suggested (Speer, 1989).

A.4.a.3. ABYSSAL FLOW INDICATIONS

Just north of the Tahitian chain a very clear signature of a deep
boundary current was found banked to the south against the islands.
Just south of the equator, where the ocean bottom rises slightly, a
clear spreading of isopycnals and isotherms indicating a deep flow
was also found.  Isopycnal analysis suggests westward flow at the
equator just above the bottom especially based on silica. The
lowered ADCP data confirm this direction.

The Clarion Fracture Zone and deep basin just north of it contained
bottom waters of the same properties found south of the equator and
not in between (high density, oxygen; low silica, phosphate,
nitrate, potential temperature, and salinity). There was strong
deep geostrophic shear in the deep basin also, all suggestive of
the eastward flow of waters expected from the western Pacific into
the eastern Pacific south of Hawaii.

Strong geostrophic shear was also found in the Hawaiian Trough,
banked against Hawaii.


A.4.b.   SMALL VOLUME AND LARGE VOLUME SAMPLE LOCATIONS 
         (Figs. A.2.3 and A.2.4)


A.5.     MAJOR PROBLEMS ENCOUNTERED ON THE CRUISE

There were no major problems resulting in shortfalls in numbers,
spacing, or coverage of the stations.

A.5.a.   WATER SAMPLE ANALYSES

A full listing of all data of questionable values, including
problems with bottle tripping and leaking, is appended as section D.

TRIPPING PROBLEMS: 
There were no notable problems with the large rosette used on most 
stations.  Bottles on the small rosette for the additional small volume 
equatorial stations were hard to configure, resulting in loss of about 
10% of the few samples collected there. Failure to switch to inner pylon 
on the large rosette at sta. 287 resulted in a lack of water samples 
above 500 meters.

SALINITY: 
Salinity analyses were noisy, on the order of 0.003- 0.004 psu in the 
deep water, throughout much of the cruise. They were also 0.003-0.004 
psu higher than those of leg 2; a preliminary at-sea comparison of the 
standard sea waters used for the two groups of stations indicated that 
the P16C salinities should be 0.001psu higher than those of leg 2. The 
remaining discrepancy is unaccounted for as of now; a second comparison 
of the SSW's will be made before looking into other possibilities. In 
order to reduce the noise level, various attempts were made in education 
of those drawing the water samples and the autosalinometer was changed 
before station 247.

NUTRIENTS: 
Difficulties were encountered with some nitrate and phosphate 
measurements on stations 226 to 244. Replicate samples using different 
sample tubes and water out of different Niskins indicated that the 
problem was with the sampling tubes used to collect water from the 
rosette sampler. All tubes were thoroughly cleaned with HCl before sta. 
245, solving the problem. With the exception of occasional random 
problems, all data from stations 221-225 and 246-326 appear acceptable.

In an attempt to ensure that nutrient data from all three WOCE legs 
would be compatible despite the different lead analysis groups, the same 
equipment and standards were used on all three legs. Silica and 
phosphate values from legs 2 and 3 are consistent with each other. 
However, nitrate on leg 3 is systematically 1-2 umoles/liter higher than 
on leg 2, apparently due to different calibration procedures.

LARGE VOLUME SAMPLING: 
Tripping problems were encountered on several large volume stations, 
necessitating a third or fourth Gerard cast in order to get a full 
profile. In general, problems of this sort were less common than on the 
first two legs, due to the good weather we enjoyed. 

A.5.b. CTD

A full description of the CTD calibration is in section B.4. The full 
CTD package consisted of pressure, temperature, redundant temperature, 
oxygen, an oxygen pump, and a transmissometer. The CTD wire had three 
conductors. Two separate CTD's were used: the primary CTD (WHOI #9) was 
used for most stations and the secondary CTD (WHOI #10) for just the 
odd-numbered stations from 251 to 285. This second CTD was mounted on a 
smaller rosette package and was used in order to halve the station 
spacing across the equator. A lowered acoustic doppler current profiler 
was also mounted on the smaller package.

The first 4 stations were noisy in pressure, oxygen and salinity. Oxygen 
calibration for stations 222-226 was not possible.

One of the three conductors in the conducting wire shorted to ground 
during sta. 234, so 9 bottles did not close. The short was measured to 
be at 5288m from the CTD, so cutting the wire was not an option. The 
CTD/rosette package was reconfigured for use with 2 conductors and used 
that way throughout the remainder of the cruise.

The wire was reterminated prior to station 259 and prior to station 303.

Bottom contact was made at stations 242, 245, and 288, causing a 
conductivity calibration shift at 245. The rosette package hit the side 
of the ship at 233, but there was no shift in CTD calibration.

The CTD conductivity sensor failed on station 294, necessitating a 
switch to a new cell.

Due to these and a problem with an apparent conductivity hysteresis, 
calibrating this CTD data set presented more problems than usual. 
Nevertheless, all but just a few of the stations in the final data set 
contain full profiles of data within WHP accuracy standards.


A.6.    List of Cruise Participants

Lynne Talley      Chief scientist             SIO          ltalley@ucsd.edu
Greg Johnson      Co-chief scientist          U.Washington gjohnson@noaapmel.gov
Paul Quay         Gerard sampling/AMS C14     U.Washingtonpdquay@u.washington.edu
George Bouchard   computer tech./marine tech. SIO
Peter Guenther    carbon dioxide analyses     SIO          pguenther@ucsd.edu
Kyung-Ryul Kim    helium-3 sampling           SIO
Leonard Lopez     large volume marine tech.   SIO/ODF      leo@odf.ucsd.edu
Gene Pillard      resident technician         SIO/MTG
Jim Wells         marine tech.                SIO/ODF      jwells@ucsd.edu
Gary Bond         CTD/hydro group leader      WHOI
George Knapp      oxygen analyses             WHOI         gknapp@whoi.edu
Peter Landry      CTD/hydro electronics tech. WHOI
Carol MacMurray   CTD/hydro processor         WHOI
Mike Mathewson    helium-3, tritium           WHOI
Ed Peltzer        carbon dioxide analyses     WHOI
Bob Stanley       salinity analyses           WHOI
Joe Jennings      nutrient analyses           OSU
Hernan Garcia     nutrient analyses           OSU
Frank Bahr        ADCP                        U.Hawaii
Dave Wisegarver   CFC sampling and analyses   NOAA/PMEL
Tracy McCallister CFC sampling and analyses   NOAA/PMEL
Carol Knudson     bio-optics stations         LDEO         knudson@ldeo.columbia.edu



B.      DESCRIPTION OF MEASUREMENT TECHNIQUES AND CALIBRATIONS

B.1.    NAVIGATION AND BATHYMETRY

GPS navigation.

Underway bathymetry was logged using the centerbeam from the R/V
Washington's Seabeam system.  The data were acquired by George
Bouchard (shipboard computer technician), who merged them with the
GPS navigation.  The data were quality-controlled and archived by
Stuart Smith of the Geological Data Center at SIO.  GPS

B.2.    ACOUSTIC DOPPLER CURRENT PROFILER (ADCP)

Text to be supplied by Eric Firing (U. Hawaii).

B.3.    THERMOSALINOGRAPH AND UNDERWAY DISSOLVED GASES

A thermosalinograph with Falmouth Scientific sensors was operated
on P16C and the two preceding WOCE legs on the R/V Washington.
This effort was unfunded and was therefore was accorded very low
priority compared with the CTD operation.  The system was set up by
Robert Williams of SIO's Oceanographic Data Facility.  He also
operated the system on the second of the WOCE legs.  Peter Salameh
of SIO did an initial cleanup of the data for all three legs.

Temperature, conductivity and oxygen sensors were located in the
ship's main laboratory in the principal clean seawater supply.
There was a steady flow of water past the sensors through most of
the three legs.  An additional temperature sensor was mounted in
the bow inlet, at 3-5 meters depth.

Temperature:  Both temperature sensors were calibrated at SIO's
Oceanographic Data Facility (ODF) before the cruise, in May 1991.
The laboratory temperature sensor (serial number 1321) was broken
when it was being removed at the end of the third leg, and so there
was no post-cruise calibration.  Its temperature offset was
approximately 0.005 C high compared with the laboratory standard.

The bow temperature sensor (serial number 1322) was calibrated at
ODF after the third leg, in February 2-5 1992.  Its temperature had
increased by about 0.2C between the pre- and post-cruise
calibrations.  Its pre-cruise calibration showed it to be about
0.01 C high compared with the laboratory standard.

Both sensors functioned well throughout the three legs.  The
average temperature difference between the two sensors for P17C was
0.081 C, with the laboratory sensor being warmer as expected.

Conductivity:  There were no laboratory conductivity calibrations.
No log was maintained for the sensors and no bottle salinity check
samples were collected for calibration during P17C. On the second
leg, a brief log was maintained and a number of check samples were
collected.  The sensor failed 11 days into the second leg, and no
conductivity was measured for the remainder of that leg or P16C.

Data for pCO2 and pN2O were taken underway with a shipboard gas
chromatograph.  Data were reported to CDIAC in Oak Ridge, Tennessee

B.4     XBT's

None

B.5     METEOROLOGICAL OBSERVATIONS

Meteorological observations where taken at each station.
Information taken at each station included dominant wave direction,
wind speed and direction, atmospheric pressure, air temperature,
weather, clouds and visibility.


C.      HYDROGRAPHIC MEASUREMENTS

A detailed list of flagged discrete data, including the reasons for
problems, is provided in section D.  Additional comments on some
bottle salinities are included in the CTD calibration sections.

C.1     CTD DATA COLLECTION AND PROCESSING 
        (Maggie Cook - WHOI; Lynne Talley - SIO)

CTD data on P16C were collected and calibrated by the WHOI CTD
group.  The CTD hardware technicians were Gary Bond and Peter
Landry and the shipboard CTD software technician was Carol
MacMurray. The shorebased CTD processor was Maggie Cook.

106 rosette/CTD stations were occupied  to the bottom along 151 W
between 17.5 S and 19 N (Table 1).  Basic station spacing was  30
nm with a 36 bottle 10-liter rosette package; spacing closed to 20
nm between 3 S and 3 N.  The backup CTD instrument, fit with a
small rosette  package (11 1.7-liter bottles),  was alternated with
the large package between  3 S and 3 N, to obtain CTD station
spacing of 10 nm near the equator.  Stations were numbered
consecutively (starting with the first leg [P17C] of the R/V
Washington work which began off the coast of California in May
1991).  The  first station on this leg (P16C), was station 221; it
was a reoccupation of  the last station (220) of Leg 2 (P16S) and a
continuation of the P16 line to the north.  Final CTD data are 2 db
averaged pressure,temperature,salinity, oxygen profiles.

Two EG&G/Neil Brown Instrument Systems (NBIS) CTD/O2 (conductivity,
temperature, depth, oxygen) profilers were employed on this cruise.
WHOI CTD #10 (serial # 3448) with the large rosette package served
as the primary instrument, being used for all stations 222 to 250,
even stations from 252 to 284, and all stations from 286 to 326.
On most stations 36 bottles were used, giving 36 calibration
points.  CTD 10's conductivity cell was changed prior to station
295.  CTD #9 (serial #01-2405-01) with the small rosette package
and lowered acoustic doppler current profiler acted as the
secondary instrument. It was used for odd stations from 251 to 285,
with a maximum of 11 calibration points for each cast.

Both CTD's were equipped with sensors to measure pressure, sea
water temperature (two channels) conductivity,  and dissolved
oxygen concentration. Both were modified to employ titanium strain
gauge pressure sensors (Millard, Bond and Toole,  1992). In
addition, an interface for an externally mounted transmissometer
was added to the CTD's at the request of investigators from Texas A
& M.

The accuracy of the final data set hinges on the calibrations of
these sensors.  Both laboratory measurements and water sample data
obtained at sea were used to calibrate sensors.  General
information on CTD calibration and  data processing procedures can
be found in the reports of Fofonoff, Hayes and  Millard (1974),
Millard and Galbraith (1982), and Millard and Yang (1993).

Laboratory calibrations, performed before and after this three leg
cruise aboard the R/V Thomas Washington, provide the sole
correction information for the CTD pressure and temperature
sensors.  These temperature and pressure calibrations are  used to
scale the 2 db data profiles as well as the CTD component of the
rosette  water sample data files.

The CTD instruments and secondary thermometers were calibrated at
the WHOI Calibration Laboratory.  The laboratory maintains primary
temperature standards at the triple point of water and the melting
point of gallium, thereby spanning most of the oceanographic
temperature range.  Weights certified periodically at the
Massachusetts Bureau of Weights and Standards employed with a Ruska
model 4280-600 dead weight tester make up the Laboratory's pressure
standard while "Wormley" water is the salinity standard.  A
precision temperature bridge interfaced to a platinum resistance
thermometer (EG&G ATB-1250, and/or NBIS CT-2) is used as a transfer
standard to calibrate the CTD instruments.  This work is carried
out in a large salt water bath whose temperature is shifted over
the oceanographic range, and/or a set of 5 small freshwater baths
held at fixed temperatures between 0 and 30 C. Full instrument
immersion is achieved in the large bath; the lower endcap and
sensor arm are immersed in the small baths.  Stability of the
transfer standards is checked regularly against the triple point
and gallium cells; based on these data the transfer standard
readings are believed accurate to +/- 1 mC.  This uncertainty is
probably doubled upon transfer to the CTD calibrations via the bath
water.

The Ruska dead weight testor is stated by the manufacturer to be
accurate to 0.01% (0.6 dbars at 6000 dbars).  Our calibration
procedure involves cycling the instrument between atmospheric
pressure and 10,000 psi and back at 1000 psi intervals, followed by
a set of measurements to 5000 psi maximum pressure and back.  This
is conducted at room temperature.  The whole procedure is then
repeated at the water ice point.  From these data, coefficients in
the polynomial regression between measured and true pressure
(Millard et al., 1993) are determined.

Finally, a laboratory conductivity calibration is performed using a
set of 5 salt water baths at room temperature spanning
conductivities between 20 and 60 mmho.  Water samples drawn and
analyzed on a Guildline Autosal, in combination with conductivity
transfer standard measurements with the 5 electrode probe of the
EG&G Bridge provide reference information.  These data verify CTD
instrument functionality, and provide initial correction
information for the CTD, which is updated with water sample
salinity measurements in the field. In general, we use the
laboratory information to determine the sensor bias (exploiting the
much larger range of conductivity available in the laboratory tanks
than in the open ocean) and use the field data to refine the
sensor's range scaling.

CTD data quality flags were set by the chief scientist.  Initially
all values which were interpolated after removal of bad data were
flagged as "6".  Where the interpolation was over a pressure
interval greater than 10 dbar, the interpolation was rechecked and
the values subjectively flagged as either "6" if the interpolated
profile fit smoothly with adjacent stations and the interpolation
was not too much larger than 10 dbar, as "3" if the interpolation
was longer and produced a questionable profile, and as "4" if the
interpolation produced a clearly unacceptable profile.
Interpolations over large pressure intervals at station 255 were
deleted entirely and the data replaced with -9.  The number of
scans listed in the CTD data files is "-9" if just one of the four
measured values was interpolated, due to a shortcoming in the WHOI
internal CTD data format.  All CTD oxygen values between the sea
surface and the heave compensator stop were flagged "3" based on
experience with the P17C and P16S/P17C CTD data sets.

C.1.a   CTD TEMPERATURE

No electronic adjustments were made to the temperature sensor
interface boards during laboratory calibrations in order to
preserve the stability history of these sensors.  Instead,
corrections, determined by polynomial least-squares fits to
laboratory calibration data, were applied to the data.  Temperature
calibrations consisted of quadratic fits to 8  temperature points
ranging between 0 and 30 degrees C in reference to the platinum
thermometer standard (Figure C.1.1).  The following quadratic
temperature correction algorithms were  used in the reduction of
CTD downcast and water sample rosette data collected on this
cruise.

The June, August and October 1991 temperature calibration data were
similar for CTD #10, and thus were combined in one polynomial fit
for application to  the CTD data.  The shift in the temperature
calibration was no more than 0.0015C, and the standard dviation of
the combined fit was 0.00104C.

CTD #9 was calibrated in August and October 1991 (pre and post
cruise).  The temperature shifted no more than 0.001C.  The post
cruise information was used for CTD #9 temprerature, for which the
standard of the fit was 0.612 x 10-4 C.

CTD #10 (combination calibrations June, August, October 1991):

T= -.232143E-3 + .499794E-3 * T(raw)+ .341585E-11 * T(raw)*T(raw)

CTD #  9 (post-cruise calibration, October, 1991):

T= -.853737E-2 + .500074E-3 * T(raw)+ .247454E-11 * T(raw)*T(raw)
where T(raw) is the raw counts of the temperature channel. A time
lag correction of 0.250 seconds between C and T sensors was also
applied.

C.1.b   CTD PRESSURE

Pre- and post- cruise pressure calibrations were completed using a
dead weight tester in the laboratory;  data were sampled at  1000
psi intervals with both increasing and decreasing pressure between
0  and 10000 psi.  Data reduction employed a quadratic calibration
algorithm determined from a least squares fit to these data (Figure
C.1.2).  Here, we ignore the average 1 dbar hysteresis
characteristic of titanium strain gauge pressure sensors and
combine  increasing and decreasing laboratory pressure data in one
quadratic fit to the data.

Following Millard et al (1993) the raw pressure data are scaled to
calibrated values with the following polynomial:
                            2
Pi = A + B * Praw + C * Praw + S1 * (Tp-T0) + S2 * (Tp-T0) * Praw

Here Praw are raw counts of the pressure channel.  T0 is a
reference temperature (21.8 degrees C which for convenience is the
room temperature for one of the pressure calibration runs) and Tp
is the (measured) temperature of the titanium strain gauge.  Thus,
S1 and S2 represent variation of the gauge bias and scale
adjustments with temperature.

The pre and post cruise calibrations for CTD 10 shifted 1.5 dbar.
The standard deviation of the fit for the post-cruise calibration
was 0.333 dbar.  The following post-cruise determined coefficients
were applied to reduce the CTD #10 data:

 A = -1.85372
 B =  1.00331E-1
 C = -0.265076E-8
S1 =  2.71E-6
S2 = -0.054

The pre and post cruise calibrations for CTD 9 shifted 1.5 dbar.
The standard deviation of the fit for the post-cruise calibration
was 0.523 dbar. The following post-cruise determined coefficients
were applied to reduce the CTD #9 data:

 A = -1.73307
 B =  1.00489E-1
 C =  0.779511E-9
S1 =  3.39E-6
S2 =  0.015

Due to a software error discovered after the cruise, the Tp data
recorded at the times of water sample acquisition were corrupted.
CTD pressure information in the water sample files was derived
using external water temperature as a substitute for the gauge
pressure Tp.  This substitution incurs error only near the surface
when the gauge temperature lags the external value.  The effect in
the derived pressure is small, comparable to the amplitude of
typical ship roll or less.  The down-cast data did not experience
this error and were reduced using the observed internal gauge
temperature.

C.1.c    CTD CONDUCTIVITY

C.1.c.1  PRE-CRUISE CONDUCTIVITY ALGORITHM

Linear conductivity calibration algorithms, derived from pre-cruise
laboratory data, were used for real time display during data
acquisition at sea.

Figure C.1.3 shows plots of recent conductivity sensor laboratory
calibrations for each CTD instrument.  Notice that the post cruise
(October, 1991) calibration for CTD 10 shows the markedly different
characteristics of the newest conductivity cell which replaced a
failed one at station 294 .

The pre-cruise conductivity algorithms employed were:
CTD # 10

C = -.734217E-02 + 0.100453E-02 * C(raw) * [1+A*(T-T0)+B*(P-P0)]

CTD # 9

C = -.944740E-02 + 0.977069E-03 * C(raw) * [1+A*(T-T0)+B*(P-P0)]

where:
C(raw) is the raw counts of the conductivity channel
A      is the temperature correction coefficient (-.65E-5 degrees C)
B      is the coefficient of cell contraction with pressure
       (This term is generally 1.5E-8 db-1.  However,  a different value for
       this term was applied to each of the three conductivity cells employed
       on this cruise.  An explanation follows in the discussion of final
       conductivity calibrations)
T      is scaled temperature
T0     is 2.8 degrees C
P      is scaled pressure
P0     is 3000 db


C.1.c.2 CONDUCTIVITY CALIBRATION PROBLEMS

The following were problems during this cruise which led to major
difficulties in the final processing of the data:

The first four stations during P16C were very noisy in pressure,
oxygen and salinity. The CTD was repaired by removal of the oxygen
pump, replacing a chip in the CTD at station 225, and increasing
the power to the CTD. CTD oxygen calibration for these data was
impossible through station 226.  Comparisons of CTD and rosette
data in the rosette water sample file show  large errors during
these first stations; this is partially due to the erratic behavior
of the CTD sensors as well as inconsistencies of rosette sampling
procedures typical of watch standers at the start of a cruise.

One of the three conductors in the CTD conducting wire shorted to
ground at station 234; the short was found to be at 5288 m wire out
thus excluding the option of cutting the wire.  The CTD/rosette
package was reconfigured for use with 2 conductors and used that
way for the remainder of the cruise.  The CTD cable was
reterminated twice during the cruise: prior to stations 259  and
303.  Bottom contact by the CTD occurred at stations 242,245, and
288. CTD station 251 downtrace data exhibited excessive noise;
thus, the uptrace data is the source of the final pressure averaged
data. The CTD #10 conductivity sensor failed during  station 294 at
which point it was replaced with a new cell.

The rosette water sample salts are of relatively poor quality for
the first part of this cruise. Of course, this is of major concern
when the rosette water sample data make up  the base of data used
for deriving conductivity calibrations.  [The variability of
rosette data in the deep water is greater than 0.005 psu.]  Water
sample quality improved through the cruise (Figures C.1.4a and
C.1.4b).

The CTD touched bottom at station 245 and the conductivity
calibration shifted prior to station 246.  This was followed by a
salinometer change between stations 246 and 247, which created
difficulties with salvaging the calibration shift.  A salinity
shift of +0.004 psu occurred between stations 245 and 246 in the
raw theta/salinity CTD profile; the replacement salinometer yielded
higher salinity values  (about 0.001-0.002 psu) after station 246.
Final calibration work with the CTD salinity data has brought the
overall shift, based on groups of stations prior to 245 and after
246, down to +0.001 to 0.002 psu which is within the standard
deviation of the water sample data. A station dependent bias was
applied to stations 228 through 245 in order to smooth out the
unphysical shift between stations 245 and 246.

Both CTD/O2 instruments (#9 and #10) intermittently showed what we
are  calling "conductivity hysteresis".  That is, the conductivity
values retrieved  during the downtrace and uptrace are
significantly different (as large as .015 mmho/cm).  This problem
was at least partially explained by residual temperature
sensitivity in the MKIII CTD conductivity interface (N.Brown,
personal communication, 1992.  An electronic fix has since been
implemented with no recurrence of the problem.) After much thought,
it was decided to modify our standard calibration scheme to derive
conductivity scalings from the down-cast information.  [Typically,
CTD information from the up-cast at the times of water sample
collection are used to derive scalings which are subsequently
applied to the down- cast.  Because of the conductivity hysteresis,
this technique yielded down profiles that were not consistent with
the water sample salinity data.]

The procedure adopted mimicked standard treatment of the CTD oxygen
data.  CTD downcast information was extracted at the depths where
bottles were taken on the up-cast.  These data were then combined
with the water sample salinity information to derive scalings for
the down-cast conductivity data.

Two CTD/O2 instruments were used on the cruise, one of which
employed two different conductivity cells.  Strangely, of the three
different  conductivity cells used, none of them could successfully
fit the  rosette water sample salts in the deep water.  After many
false starts and much thought, we finally applied a negative
conductivity pressure adjustment term ("B" in the algorithm in
section C.1.c.1).  to CTD #9 stations and a zero conductivity
adjustment term to CTD #10 stations (both CO sensors).  This is
highly unorthodox since the term  is then describing these
conductivity cells as either expanding or remaining of constant
dimension with increasing depth.  Despite the ad hoc nature of this
method, it significantly improves the consistency between CTD and
bottle conductivities in the deep water.  It has, on the other
hand, induced an 0.002 difference between the two CTD instruments
in the mid potential temperature range (2 - 7C) where there is
minimal high quality rosette data, particularly for CTD #9.

Lastly, frequent problems with conductivity were encountered at the
sea surface.  Thus the first good conductivity listed for many
stations is at 3 or 5 dbars rather than at 1 dbar.  The problem is
likely due to contamination of the average conductivity by
measurements in air prior to the package being fully submerged.

C.1.c.3 FINAL CONDUCTIVITY CALIBRATION

Final conductivity calibrations were derived from a least-squares
regression of CTD and water sample conductivity data to determine
the slope  and bias terms in the earlier mentioned algorithms
(Millard and Galbraith,  1982).  For both CTD/O2 instruments, the
regression routine for estimating conductivity bias and slope
adjustments was initially run over all water sample data using the
nominal  cell deformation terms in the conductivity scaling
equation.  Time series plots of water sample minus CTD conductivity
differences were then constructed to identify station subgroups in
which the CTD conductivity cell appeared to be stable (or drifted
linearly) with time (Figure C.1.4a and C.1.4b). Expanded-scale
potential temperature/salinity plots were also used to  confirm the
groupings.  Identified station groups with apparent homogeneous
calibration characteristics were then rerun separately through
least-squares regression fits of CTD and water sample conductivity
data to obtain new conductivity bias and slope terms for each group
over the entire water column. The slope term was then further
refined by removing the conductivity bias term from the fit and
refitting for conductivity slope only in the deep water  (usually
below 1500 db).  Note that the laboratory conductivity  bias term
was used for CTD # 10, while the regression conductivity bias term
was employed for CTD #9 whose laboratory conductivity calibration
appeared to be  in error (i.e. it did not describe the instrument
behavior in the field).

Once station groups were identified it was necessary to apply
station  dependent conductivity slope adjustments to several
station groupings whose time series plots showed a distinct drift
with time.  In addition, several stations required subjective
conductivity slope adjustments to bring the odd station back in
line with neighboring station theta/salinity profiles.  Many of
these adjustments were large (on the order of 0.006 psu in either
direction)  suggesting periodic instability of the CTD instruments
being used.

Careful examination of the deep-water temperature/salinity
information  revealed a .001-.002 departure of the CTD trace from
the water sample data in the deep water.  This discrepancy was
minimized by modifying the coefficient of cell deformation with
pressure as noted above.  Data groups were refit for conductivity
calibration terms. Two recently analyzed data sets have  had
similar adjustments to the beta term in order to improve
consistency between rosette and CTD salinity in the deep water
(TPS-10, Epic Voyagers, 1991;  Charles Darwin Cruise 29, Cook et al
1992).

The basic station groupings with derived conductivity bias and
slope coefficient terms are listed below.

CTD # 10 conductivity sensor A:

stations group  stations      bias          slope

226 - 244       221-245       -.113775E-1  .10043116E-2
*****
252 - 286 even  246-250 all
                252-262 even  -.113775E-1  .10043321E-2
*****
264 - 284 even  264-284 even
286 - 292 all   286-294 all   -.113775E    -1.10043156E-2

CTD # 10 conductivity sensor B:

295 - 298       295-298       .122951E-2   .10071577E-2
300 - 311       299-310        station dependent slope
311 - 324       311-326       .122951E-2     .10070779E-2

CTD #9  conductivity sensor:

257 - 273 odd   251-273 odd    -.039       .975862E-3
275 - 285 odd   275-285 odd    station dependent slope


Further station by station adjustments to the conductivity slope
terms of the above regression groupings are listed below.

           station  amt of adjust  new co slope term
          --------  -------------  -----------------
             221    -.003          .10042366E-2
             222    -.008          .10041116E-2
             223    -.010          .10040616E-2
             224    -.010          .10040616E-2
             225    -.008          .10041116E-2
             226    -.003          .10042366E-2
             241    +.0015         .10043516E-2
             251    +.016          .97536222E-3
             253    +.006          .97600631E-3
             259    -.001          .97585950E-3
             261    -.002          .97585700E-3
             263    -.001          .97585950E-3
             256    +.002          .10043821E-2
             258    +.002          .10043821E-2
             293    +.003          .10043906E-2
             294    +.004          .10044156E-2

Thus, the final conductivity bias and slope terms for all stations
of the P16C CTD cruise, except for the station-dependent salinity
correction applied after this calibration, follow:

              station    BIAS        SLOPE
              -------   ----------   -----------
              221      -.113775E-1  .10042366E-2
              222      -.113775E-1  .10041116E-2
              223      -.113775E-1  .10040616E-2
              224      -.113775E-1  .10040616E-2
              225      -.113775E-1  .10041116E-2
              226      -.113775E-1  .10042366E-2
              227-240  -.113775E-1  .10043116E-2
              241      -.113775E-1  .10043516E-2
              242-245  -.113775E-1  .10043116E-2
              246-250  -.113775E-1  .10043321E-2
              251      -.039        .97536222E-3
              252      -.113775E-1  .10043321E-2
              253      -.039        .97600631E-3
              254      -.113775E-1  .10043321E-2
              255      -.039        .97586200E-3
              256      -.113775E-1  .10043821E-2
              257      -.039        .97586200E-3
              258      -.113775E-1  .10043821E-2
              259      -.039        .97585950E-3
              260      -.113775E-1  .10043321E-2
              261      -.039        .97585700E-3
              262      -.113775E-1  .10043321E-2
              263      -.039        .97585950E-3
              264      -.113775E-1  .10043156E-2
              265      -.039        .97586200E-3
              266      -.1137-1     .10043156E-2
              267      -.039        .97586200E-3
              268      -.113775E-1  .10043156E-2
              269      -.039        .97586200E-3
              270      -.113775E-1  .10043156E-2
              271      -.039        .97586200E-3
              272      -.113775E-1  .10043156E-2
              273      -.039        .97586200E-3
              274      -.113775E-1  .10043156E-2
              275      -.039        .97616069E-3
              276      -.113775E-1  .10043156E-2
              277      -.039        .97612010E-3
              278      -.113775E-1  .10043156E-2
              279      -.039        .97607951E-3
              280      -.113775E-1  .10043156E-2
              281      -.039        .97603893E-3
              282      -.113775E-1  .10043156E-2
              283      -.039        .97599834E-3
              284      -.113775E-1  .10043156E-2
              285      -.039        .97595775E-3
              286-292  -.113775E-1  .10043156E-2
              293      -.113775E-1  .10043906E-2
              294      -.113775E-1  .10044156E-2
              295-298  .122951E-2   .10071577E-2
              299      .122951E-2   .10072015E-2
              300      .122951E-2   .10072043E-2
              301      .122951E-2   .10071942E-2
              302      .122951E-2   .10071841E-2
              303      .122951E-2   .10071740E-2
              304      .122951E-2   .10071639E-2
              305      .122951E-2   .10071538E-2
              306      .122951E-2   .10071437E-2
              307      .122951E-2   .10071336E-2
              308      .122951E-2   .10071235E-2
              309      .122951E-2   .10071134E-2
              310      .122951E-2   .10071033E-2
              311      .122951E-2   .10070932E-2
              312-326  .122951E-2   .10070779E-2

An upward jump in conductivity between stations 245 and 246, of
0.002 to 0.004 psu, was concluded to have resulted from bottom
contact during station 245.  Since there had been a slow shift in
calibration prior to station 245, the shift was smoothed out by
applying a station dependent salinity bias to stations 228 to 245.
This correction was not performed on the conductivity data because
it was done in 1995, long after the initial calibration.

                  Sta.  Salinity bias correction
                  ---   ------------------------
                  228   0.0000000e+000
                  229  -1.1764706e-004
                  230  -2.3529412e-004
                  231  -3.5294118e-004
                  232  -4.7058824e-004
                  233  -5.8823529e-004
                  234  -7.0588235e-004
                  235  -8.2352941e-004
                  236  -9.4117647e-004
                  237  -1.0588235e-003
                  238  -1.1764706e-003
                  239  -1.2941176e-003
                  240  -1.4117647e-003
                  241  -1.5294118e-003
                  242  -1.6470588e-003
                  243  -1.7647059e-003
                  244  -1.8823529e-003
                  245  -2.0000000e-003

Finally, manual editing of random data spikes (salt and
temperature) was done, usually interpolating across the pressure
bounds of the spikes (Table C.1.2).

Uncertainty in the final CTD salinity data may be measured by
differences between CTD and water sample salinity data. Of course,
absolute CTD salinity accuracy hinges on the accuracy of the water
sample data.  A time series plot of salinity differences as a
function of station number shows the final data to be uniformly
calibrated (Figure C.1.5).  Plots of salinity and oxygen
differences vs. depth show the consistency of the final calibrated
CTD data to the rosette water sample data (Figure C.1.7).  The
histogram  of salinity differences for the full data set (Figure
C.1.8) is Gaussian with a mean indistinguishable from zero as would
be expected from random measurement error.  The  standard deviation
of the population is 0.0017 psu in the deep water (pressure greater
than 2000 db).  We consider this latter figure to be representative
of the overall uncertainty in the salinity data.

C.1.c.4 ADDITIONAL COMMENTS ON THE CONDUCTIVITY CALIBRATION

A. The average difference between the bottle and CTD salinities for
   potential temperatures less than 5.0C is 5.33E-04, with the CTD
   slightly lower than the bottles, based on the CTD and bottle
   salinities in the final bottle data file, dated October 27, 1993.

   The first eight stations have somewhat lower CTD salinities: for
   potential temperature less than 5.0C, the average difference over
   stations 222 to 228 is 2.48E-03.  The average difference over
   stations 229 to 326 is 3.72E-04.

B. As should be expected, there is a difference between CTD 9 and
   10, as indicated by salinity and pressure on deep isotherms
   (Figures C.1.9, C.1.10 and table). The differences between the two
   CTD's are within the WHP guidelines for accuracy (0.002), and are
   close to the precision guidelines (0.001).  CTD 9 salinity is
   fresher than CTD 10, and the differences between the two are
   particularly striking for CTD 9 stations 253 to 261 and for 277 to
   285.  The differences are less for the intermediate stations
   263 to 275.

Average differences and standard deviations on isotherms:
CTD10 (stations 250-286) - CTD9 (stations 251-285)

             theta   del S   sig S        del P  sig P
             -----   ------  -----------  -----  -----
             2.000   0.0024  -0.4170E-03  -19.4   -1.8
             1.900   0.0022  -0.8048E-03  -18.7    3.4
             1.800   0.0019  -0.7370E-03  -20.5   -9.9
             1.700   0.0020  -0.6350E-03  -22.2    4.7
             1.600   0.0016  -0.1006E-02  -11.5    1.3
             1.500   0.0011  -0.1394E-02   -0.2    3.6
             1.400   0.0007  -0.1154E-02  -17.1  -13.3
             1.300   0.0006  -0.1077E-02  -14.0   -2.5
             1.200   0.0004  -0.8197E-03  -16.2    3.9
             1.100  -0.0002  -0.9853E-03  -28.0   14.4


C. For these locations, for theta < 5C, bottle/CTD salinity
   differences are greater than 0.01:

          sta  bot  pres      bottle-CTD salt  new flagging
          ---  ---  -------   ---------------  ------------
          223  15   1537.00   1.03989E-02      not flagged
          224  15   798.900   1.56975E-02      not flagged
          224  10   1638.40   1.12991E-02      not flagged
          225  14   1618.80   1.02005E-02      not flagged
          240  17   1635.00  -1.28021E-02      flag=3
          253   6   1538.00   1.17989E-02      not flagged
          300  21   928.100   1.42975E-02      flag=3
          317  20   926.300   1.91994E-02      not flagged
          321  21   720.200   1.95007E-02      not flagged

Sta. 223/1/15/1537 dbar: 
This is merely the worst of a set of bottle-CTD salinities in which the 
bottles are higher than the CTD: the point just above is .008 different. 
The problem appears to be more in the CTD salinity processing than in 
the bottle salts, and so the bottle salts are not flagged.

Sta. 224/1/10,15/1638, 799 dbar: 
Likewise, these are the two worst of a series of bottle salinities which 
are higher than the calibrated CTD salinity, and since the station is 
close to the start of the cruise when it appears that the calibration 
was settling in, none of the bottles have been flagged.

Sta. 225/2/14/1619 dbar: 
Also in the group of starting stations, although the differences here 
are also negative in part. The two separate casts of 225 result in some 
inconsistencies in the differences between bottle and CTD salinities as 
well. This particular bottle is high relative to the cast 2 CTD, but 
appears to be quite low relative to the cast 5 CTD and other salinities.

Sta. 240/1/17/1635 dbar: 
This bottle salinity is low, rather than high. It is one of many which 
are lower than the CTD on this station; the bottle just above it is 
almost as low. Because it creates a unsmoothness in the bottle salinity 
profile which is not present in the CTD profile, it has been flagged as 
3.

Sta. 253/1/6/1538 dbar: 
This is one of several bottles which is high on this station. The total 
number of bottles for calibration is quite small and the spacing in 
potential temperature is poor, so it is difficult to determine if this 
bottle should be flagged or not, so it was not flagged. This was a CTD 9 
station which was particularly difficult to calibrate.

Sta. 300/3/21/928 dbar: 
This bottle is pretty clearly the worst fitting of the bottles on this 
cast, although the one just above it is also slightly high. It has been 
flagged as questionable (3) in the .sea file.

Sta. 317/1/20/926 dbar: 
This value is rather high, but the station shows interleaving and this 
bottle is at the top of a weak deep layer. Therefore, it could possibly 
be real, and is not flagged.

Sta. 321/1/21/720 dbar: 
This is likewise a station with interleaving and the bottle in question 
is near 5C, so the salinity was not flagged. 

C.1.d   CTD OXYGEN

As noted above, the first set of stations were very noisy.  CTD
oxygen calibration was not possible for stations 221 through 226.
At station 251, on which the upcast was used, CTD oxygen was
salvageable only for 191 to 2059 dbar.  On station 255 there are no
oxygens for pressures less than 193 dbar.

In processing the P17C and P16S/P17S data (SIO's Oceanographic Data
Facility), which preceded P16C on the same ship with the same deck
equipment, it was noted that the oxygen sensor usually drifted
badly at the heave compensator stop near 20 dbar, so all oxygen
values above that depth were considered to be questionable.
Therefore all oxygens from the surface to the compensator stop were
flagged "3" in this P16C data set; the pressure at the stop was
clear from the number of scans listed unless there were bad values
and the scans were listed as "-9". Also, the surface oxygen value
(1.0 dbar) is bad on almost all stations and has been flagged 4. It
should not be used under any circumstances.

Coefficients in the CTD oxygen sensor calibration algorithm were
derived from in situ water sample oxygen data following Owens and
Millard (1985).  The algorithm is:
Oxm=
[A * (Oc + B * dOc/dt) + C] * Oxsat(T,S)e** D*[T+E*(T0-T)]+F*P

Where
Oc         is the measured oxygen current
T0         is the measured oxygen temperature
Oxsat(T,S) is the oxygen saturation according to Weiss (1970)
A          is the oxygen current slope
B          is the oxygen sensor lag
C          is the oxygen current bias
D, E, F    are representative adjustments for the oxygen sensor's
           teflon membrane permeability sensitivity to temperature and pressure.

Initially, in the CTD oxygen calibration procedure, plots were made
of differences between rosette and CTD oxygen data (using nominal
calibrations to calculate CTD oxygens).  Based upon these plots,
CTD oxygen data were  subdivided into station groups which appeared
to have homogeneous calibration  characteristics.  A multiple
regression technique was then employed to define  the coefficients
in the above equation.  As mentioned earlier, the regression  is
between downcast CTD oxygen sensor data and rosette water sample
observations obtained on the upcast.  This, is necessary because
erroneous  CTD oxygen data are obtained when the underwater package
is stopped to close  a rosette bottle.  In addition, the oxygen
sensor characteristically exhibits  excessive up-down hysteresis.

During the P16C cruise, small station groups were typically used
for regression analysis to account for frequent oscillations in
oxygen sensor characteristics. No CTD oxygen data are available for
stations 221-226 and 251 due to the poor  quality of the CTD data
and the inability of the above algorithm to describe  the oxygen
sensor characteristics.  Erratic oxygen spiking occurred during the
stations between 264 and 291 which were collected with CTD #10.
These data  were salvaged through extensive editing of data spikes
in the 1500-3000 db  range (Table C.1.2).

Despite the forementioned problems, the quality of the final CTD
data oxygen set for P16C is very good.  As with the salinity data,
a measure of CTD derived  oxygen data uncertainty is given by
comparison with the water sample data  (Figures C.1.6 and C.1.8 but
the absolute accuracy depends directly on the water sample
accuracy.  The population of oxygen difference data has a standard
deviation of 0.024 ml/l in the deep water (pressure greater than
2000 db), with a mean indistinguishable from zero.

The following details the station groupings used to generate the
final data:

CTD 10:
station grouping 227-234  used for stations 227-233
station          234      used for station  234     (alone)
station grouping 235-237  used for stations 235-237
station grouping 238-240  used for stations 238-240
station          241      used for station  241     (alone)
station grouping 241-242  used for station  242     (alone)
station grouping 243-245  used for stations 243-280
station grouping 282-288  (even) used for stations 282-288 (even)
station grouping 289-293  used for stations 289-293
station grouping 294-295  used for stations 294-295
station grouping 296-299  used for stations 296-299
station grouping 300-304  used for stations 300-304
station grouping 305-310  used for stations 305-310
station grouping 311-316  used for stations 311-321
station grouping 322-326  used for stations 322-326

CTD 9:
station          253 (alone)    used for station  253     (alone)
station          257 (alone)    used for station  257     (alone)
station          259 (alone)    used for station  259     (alone)
station grouping 261-271 (odd)  used for stations 261-272 (odd)
station grouping 273-285 (odd)  used for stations 273-285 (odd)


Thus, the final algorithm terms applied to all stations of the P16C
CTD cruise are as follows:

                            Table C.1.1
                 Final P16C Calibration Parameters
CTD 10:
    O2DIF   BIAS        SLOPE   PCOR         TCOR           % OT    LAG

227 0.0671   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
228 0.0688   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
229 0.0975   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
230 0.0919   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
231 0.1064   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
232 0.1312   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
233 0.1410   0.3900E-01   0.8518   0.1483E-03   -0.2485E-01   0.8930   2.66
234 0.1722  -0.7900E-01   1.232    0.1572E-03   -0.3670E-01   0.7500   8.00
235 0.2070   0.3200E-01   0.8889   0.1524E-03   -0.2666E-01   0.7500   5.37
236 0.1826   0.3200E-01   0.8889   0.1524E-03   -0.2666E-01   0.7500   5.37
237 0.2129   0.3200E-01   0.8889   0.1524E-03   -0.2666E-01   0.7500   5.37
238 0.1998   0.3800E-01   0.8831   0.1516E-03   -0.2494E-01   0.9653  -0.99
239 0.2219   0.3800E-01   0.8831   0.1516E-03   -0.2494E-01   0.9653  -0.99
240 0.3021   0.3800E-01   0.8831   0.1516E-03   -0.2494E-01   0.9653  -0.99
241 0.3140   0.2800E-01   0.9375   0.1472E-03   -0.2684E-01   0.8602   8.00
242 0.3190   0.6400E-01   0.8087   0.1468E-03   -0.2326E-01   0.9935   4.07
243 0.2293  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
244 0.2372  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
245 0.2304  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
246 0.2153  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
247 0.1988  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
248 0.1954  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
249 0.2009  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
250 0.1982  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
252 0.1991  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
254 0.2056  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
256 0.1922  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
258 0.2020  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
260 0.1954  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
262 0.1868  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
264 0.1694  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
266 0.1593  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
268 0.1558  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
270 0.1575  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
272 0.1421  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
274 0.1180  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
276 0.0874  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
278 0.1408  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
280 0.1568  -0.8000E-02   1.027    0.1524E-03   -0.2914E-01   0.8675   1.38
282 0.1602  -0.1000E-02   0.9945   0.1516E-03   -0.2826E-01   0.9059   5.38
284 0.1510  -0.1000E-02   0.9945   0.1516E-03   -0.2826E-01   0.9059   5.38
286 0.1833  -0.1000E-02   0.9945   0.1516E-03   -0.2826E-01   0.9059   5.38
287 0.1664  -0.1000E-02   0.9945   0.1516E-03   -0.2826E-01   0.9059   5.38
288 0.1812  -0.1000E-02   0.9945   0.1516E-03   -0.2826E-01   0.9059   5.38
289 0.2033   0.1000E-02   1.002    0.1484E-03   -0.2844E-01   0.8269   7.60
290 0.1918   0.1000E-02   1.002    0.1484E-03   -0.2844E-01   0.8269   7.60
291 0.2024   0.1000E-02   1.002    0.1484E-03   -0.2844E-01   0.8269   7.60
292 0.1969   0.1000E-02   1.002    0.1484E-03   -0.2844E-01   0.8269   7.60
293 0.2057   0.1000E-02   1.002    0.1484E-03   -0.2844E-01   0.8269   7.60
294 0.1882   0.2000E-02   0.9787   0.1499E-03   -0.2683E-01   0.8371   6.25
295 0.1826   0.2000E-02   0.9787   0.1499E-03   -0.2683E-01   0.8371   6.25
296 0.1950   0.5000E-02   0.9738   0.1504E-03   -0.2689E-01   0.8338   6.01
297 0.1904   0.5000E-02   0.9738   0.1504E-03   -0.2689E-01   0.8338   6.01
298 0.1836   0.5000E-02   0.9738   0.1504E-03   -0.2689E-01   0.8338   6.01
299 0.1923   0.5000E-02   0.9738   0.1504E-03   -0.2689E-01   0.8338   6.01
300 0.2178   0.0000E+00   1.023    0.1463E-03   -0.2919E-01   0.7500   7.23
301 0.1875   0.0000E+00   1.023    0.1463E-03   -0.2919E-01   0.7500   7.23
302 0.2230   0.0000E+00   1.023    0.1463E-03   -0.2919E-01   0.7500   7.23
303 0.2234   0.0000E+00   1.023    0.1463E-03   -0.2919E-01   0.7500   7.23
304 0.2124   0.0000E+00   1.023    0.1463E-03   -0.2919E-01   0.7500   7.23
305 0.1805   0.2000E-02   0.9925   0.1473E-03   -0.2891E-01   0.7500   8.00
306 0.1907   0.2000E-02   0.9925   0.1473E-03   -0.2891E-01   0.7500   8.00
307 0.1928   0.2000E-02   0.9925   0.1473E-03   -0.2891E-01   0.7500   8.00
308 0.2231   0.2000E-02   0.9925   0.1473E-03   -0.2891E-01   0.7500   8.00
309 0.2151   0.2000E-02   0.9925   0.1473E-03   -0.2891E-01   0.7500   8.00
310 0.2072   0.2000E-02   0.9925   0.1473E-03   -0.2891E-01   0.7500   8.00
311 0.2163   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
312 0.2027   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
313 0.1749   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
314 0.1886   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
315 0.1775   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
316 0.1702   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
317 0.1726   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
318 0.1825   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
319 0.1834   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
320 0.1847   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
321 0.1345   0.0000E+00   1.022    0.1439E-03   -0.2980E-01   0.7500   8.00
322 0.0624   0.0000E+00   1.032    0.1407E-03   -0.3134E-01   0.8407   3.84
323 0.0396   0.0000E+00   1.032    0.1407E-03   -0.3134E-01   0.8407   3.84
324 0.0162   0.0000E+00   1.032    0.1407E-03   -0.3134E-01   0.8407   3.84
325-0.0231   0.0000E+00   1.032    0.1407E-03   -0.3134E-01   0.8407   3.84
326 0.1127   0.0000E+00   1.032    0.1407E-03   -0.3134E-01   0.8407   3.84

CTD 9: 
    O2DIF   BIAS        SLOPE   PCOR         TCOR           % OT    LAG

253-0.0794  -0.2800E-01   0.9616   0.1677E-03   -0.3043E-01   0.9670   8.00
255-0.2434  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
257-0.1835  -0.2300E-01   0.9127   0.1708E-03   -0.3175E-01   0.7500   8.00
259-0.2732  -0.2400E-01   0.8979   0.1658E-03   -0.3049E-01   0.7500   8.00
261-0.1926  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
263-0.2275  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
265-0.2261  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
267-0.2458  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
269-0.2618  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
271-0.2847  -0.1500E-01   0.8771   0.1717E-03   -0.2957E-01   0.7500   8.00
273-0.3036  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06
275-0.3014  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06
277-0.3078  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06
279-0.3034  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06
281-0.2866  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06
283-0.2687  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06
285-0.2705  -0.4000E-02   0.8285   0.1658E-03   -0.2805E-01   0.8403   5.06


                              TABLE C.1.2
               MANUAL EDITING OF THE P16C CTD DATA
    STATION #  Pressure (db)  Type of edit
    ---------  -------------  -----------------
    221        1819 - 1823    interpolate TE,SA
               1 - 3639       ZERO all OX
    222        1459 - 1463    interpolate TE,SA
               3147 - 3151    interpolate TE,SA
               3679 - 3685    interpolate TE,SA
               1 - 3007       ZERO all OX
    223        3761 - 3769    interpolate TE,SA
               1 - 4119       ZERO all OX
    224        1093 - 1097    interpolate TE,SA
               1251 - 1259    interpolate TE,SA
               1625 - 1629    interpolate TE,SA
               2665 - 2671    interpolate TE,SA
               1 - 3421       ZERO all OX
    225        643 - 695      interpolate TE,SA
               991 - 997      interpolate TE,SA
               1105 - 1109    interpolate TE,SA
               1591 - 1595    interpolate TE,SA
               1 - 4381       ZERO all OX
    226        1575 - 1579    interpolate TE,SA
               1961 - 1965    interpolate TE,SA
               2781 - 2785    interpolate TE,SA
               3701 - 3709    interpolate TE,SA
               3811 - 3827    interpolate TE
               4349 - 4371    interpolate TE
               3811 - 3825    interpolate SA
               4349 - 4365    interpolate SA
               1 - 4593       ZERO all OX
    227        2965 - 2969    interpolate TE,SA
    229        1              set surface SA = 36.345
    235        301 - 321      interpolate OX
    236        1              set surface OX =  4.884
               7              set OX VALUE = 4.827
               41             set OX VALUE = 4.848
               79             set OX VALUE = 4.762
               121            set OX VALUE = 4.352
               159            set OX VALUE = 3.968
               199            set OX VALUE = 3.685
               3 - 7          interpolate OX
               7 - 41         interpolate OX
               41 - 79        interpolate OX
               79 - 121       interpolate OX
               121 - 159      interpolate OX
               159 - 199      interpolate OX
               199 - 209      interpolate OX
               325 - 355      interpolate OX
    237        1              set surface SA = 35.942
    241        289 - 293      interpolate SA
    249        1911 - 1919    interpolate SA
    250        3-5            set TE and SA values to same as 7db values 
               567 - 571      interpolate SA
               4843           set bottom SA = 34.700
               4785 - 4843    interpolate SA
    251        4              set surface SA to 6 db value 
    758 - 792                 interpolate SA
               1008 - 1028    interpolate SA
               1732 - 1742    interpolate SA
               1746 - 1754    interpolate SA
               1756 - 1768    interpolate SA
               1770 - 1784    interpolate SA
               2014 - 2028    interpolate TE,SA,OX
               2058 - 2092    interpolate SA
               2454 - 2460    interpolate SA
               2014 - 2028    interpolate SA
               3054 - 3732    interpolate TE
               2087           set OXYGEN =  2.557
               3071           set OXYGEN = 3.247
               3545           set OXYGEN = 3.529
               4579           set OXYGEN = 4.240
               4794           set OXYGEN = 4.240
               768 - 786      interpolate OX
               2062 - 2087    interpolate OX
               2087 - 3071    interpolate OX
               3071 - 3545    interpolate OX
               3545 - 4579    interpolate OX
               4580 - 4794    interpolate OX
               1 - 191        ZERO all OX
               ALL DATA       interpolate 2db average even listings
                              to 2db average odd listings

    252        1-3            set TE and SA values to 5 db values
    253        2855 - 2859    interpolate OX
               2865 - 2883    interpolate OX
               4627 - 4631    interpolate OX
               4647 - 4667    interpolate OX
    255        5 - 11         interpolate TE
               45 - 207       ZERO TE
               255 - 267      interpolate TE
               1 - 221        ZERO SA
               227 - 237      interpolate SA
               251 - 267      interpolate SA
               1 - 191        ZERO all OX
               3111 - 3131    interpolate OX
               4307 - 4313    interpolate OX
    256        1-3            set TE and SA values to 5 db values
    257        2249 - 2317    interpolate OX
               2743 - 2767    interpolate OX
               3837 - 3857    interpolate OX
               4901           set bottom OX = 4.30
               4805 - 4901    interpolate OX
    259        3515 - 3531    interpolate OX
               3759 -3763     interpolate OX
    261        4137 - 4185    interpolate OX
    264        1599 - 1605    interpolate OX
               1635 - 1643    interpolate OX
               1647 - 1651    interpolate OX
               1659 - 1667    interpolate OX
               1669 - 1677    interpolate OX
               1681 - 1687    interpolate OX
               1693 - 1697    interpolate OX
               1703 - 1711    interpolate OX
               1719 - 1727    interpolate OX
               1735 - 1739    interpolate OX
               1965 - 1871    interpolate OX
               2025 - 2029    interpolate OX
    265        1029 - 1033    interpolate TE,SA
               1237 - 1241    interpolate TE,SA
               1245 - 1253    interpolate TE,SA
               1687 - 1695    interpolate TE,SA
               1745 - 1751    interpolate TE,SA
    268        311 - 327      interpolate SA
               3067 - 4389    APPLY SA BIAS = .0028
               3067 - 3075    interpolate SA
               2313 - 2327    interpolate OX
               2401 - 2407    interpolate OX
               2433 - 2443    interpolate OX
               2557 - 2563    interpolate OX
               2605 - 2611    interpolate OX
               2727 - 2735    interpolate OX
    270        1641 - 1647    interpolate OX
               1693 - 1699    interpolate OX
    274        1339 - 1345    interpolate OX
               2665 - 2675    interpolate OX
               2693 - 2701    interpolate OX
               2725 - 2731    interpolate OX
               2745 - 2753    interpolate OX
    278        1-3            set TE and SA values to 5 db values 
    143 - 151                 interpolate SA
    279        1-3            set SA value to same as 5 db value 280 
    595 - 601                 interpolate SA
    283        1              set SURFACE OX = 5.316
    285        125 - 163      interpolate SA
               2273 - 2277    interpolate SA
    286        643 - 647      interpolate SA
               653 - 657      interpolate SA
    287        1 - 3          set TE and SA to same as 5 db  value 
    294        2101           set SA value =  34.644
               2351           set SA value =  34.660
               2503           set SA value =  34.664
               2685           set SA value =  34.668
               2909           set SA value =  34.673
               3151           set SA value =  34.678
               3403           set SA value =  34.682
               3665           set SA value =  34.688
               4001           set SA value =  34.692
               4301           set SA value =  34.695
               4635           set SA value =  34.696
               5347           set SA value =  34.696
               5475           set end SA value =  34.696
               1993 - 2101    interpolate SA
               2101 - 2351    interpolate SA
               2351 - 2503    interpolate SA
               2503 - 2685    interpolate SA
               2685 - 2909    interpolate SA
               2909 - 3151    interpolate SA
               3151 - 3403    interpolate SA
               3403 - 3665    interpolate SA
               3665 - 4001    interpolate SA
               4001 - 4301    interpolate SA
               4301 - 4635    interpolate SA
               4635 - 5347    interpolate SA
               5347 - 5475    interpolate SA
    304        91 - 99        interpolate SA
    306        3              set SA to value of 5 db scan
    322        3 - 5          set TE and SA to values of 7 db scan
               5              set surface SA = 34.648
               3              set surface TE = 26.621
               5              set surface TE = 26.621
               555 - 561      interpolate SA
               571 - 605      interpolate SA
               931 - 945      interpolate SA
               571 - 605      interpolate OX
               769 - 773      interpolate OX
               875 - 883      interpolate OX


C.1.e   CTD - INDIVIDUAL STATION COMMENTS

Stations 221-225: 
noisy, with pressure, oxygen and salinity spikes. The CTD was cabled to 
only one center conductor, with the other two conductors being wired to 
the two rosette pylons for the 36 bottle rosette package. Redundant temp 
was not coming up the wire. Oxygen severely erratic. Prior to station 
225, the OTM sensor (redundant temp) was temporarily disconnected to try 
to increase current to the CTD and oxygen pump. CTD failure at 1600m on 
the upcast, all AC went dead. Cast aborted at 1500m. The IC chip was 
replaced, station 225 cast 5 (2000m) still noisy. Increased voltage to 
the fish by switching to a different power supply.

Station 226: 
somewhat cleaner but somehow out of phase towards the end of cast. 
Removed SBE oxygen pump to reduce total power consumption of CTD 
package. Use of pump exceeded compliance voltage capability (150 VDC).

Station 227: 
Phase adjusted, and data were very clean, oxygen and pressure very 
smooth. No hysteresis (which was evident on prior stations).

Seabeam had problems (gyro?) between sta 227 and 228.

Stations 231-233: 
O2 dropouts on the upcasts. CTD package hit side of ship upon retrieval 
of sta 233. Three bottles broken.

Station 234: 
O2 dropouts on upcast. Upon retrieval of sta 234, bottles 17-24 were not 
fired. Failure was due to short to seaground in center conductor of E/M 
wire (pylon # 1-24 position). Short 113 ohms from slipring and 180 ohms 
from fish termination. Rewired CTD pkg with one conductor dedicated to 
pylon # 1 plus CTD and second conductor to pylon # 2.

Stations 235 and 236: 
O2 dropouts first 350 m on downcast. Sta 235 O2 dropouts and redundant 
temperature problems on upcast.

Station 242: 
bottom contact but no conductivity shift.

Station 245: 
bottom contact; 0.004 psu salinity shift between 245 and 246. After 
nearly final calibration, potential temperature/salinity profiles for 
the groups of stations before and after this shift overlaid very well, 
within 0.002. There was a marked shift, of about 0.002 (coldest) to 
0.004 (around 1.4C) at this point. Since this shift was judged to be due 
to the bottom contact of the CTD on station 245, and since the 
calibration was drifting slightly prior to this station, a station 
dependent bias correction was applied to stations 228 to 245.

Station 251: 
First lowered acoustic doppler (LADCP) station, using CTD #9. Its 
battery was weak from sitting in sun on deck. Not enough current to 
fish. As a result, conductivity jumped near end of downcast when more 
voltage was applied. Station was processed by pressure sorting the 
upcast. This station was noisier than most other stations.

Stations 251, 253, 255 (CTD 9): 
pressure hysteresis. Sensor settled down by stations 257 and 259. 
Hysteresis came back station 261 and seemed to remain a characteristic 
for the duration of casts with CTD 9.

Station 253: 
(CTD 9) salinity is lower than surrounding stations by about 0.005 - 
0.007 for potential temperature about 1.3C and 5.8C (800-2800 dbar) 
(Fig. C.1.9). The offset is smaller although still marked below 2800 
dbar. This station should be used only with extreme caution. All 
salinities are flagged as 3. An offset was not applied because the error 
is not of the same magnitude throughout the water column.

Station 259: 
Retermination prior to station. Just before deploying 259, fatal failure 
with CTD 9. OTM board fried. As a result, redundant temperature had a 
serious departure from the platinum temperature for this station. For 
the rest of the CTD 9 stations, CTD 10's OTM was used. It was switched 
out every station.

Stations 264-291: 
Erratic oxygen spiking CTD 10 stations only. Seemed pressure related- 
1500-300db range only. Major editing done.

Station 286: 
to reduce oxygen spiking, tied off endcaps, lowered compliance voltage 
and debubbled receptacle. Spiking variable until stations 290-291 when 
spikes mysteriously disappeared.

Station 288: 
bottom contact. No apparent conductivity shift between 288 and 289.

Station 292: 
conductivity started drifting fresh.

Station 294: 
conductivity cell died. Replaced sensor prior to station 295. Salinity 
was interpolated and is flagged 4 for 1993- 5471 dbar.

Station 302: 
OTM flaky on upcast. New termination prior to station 303, as the sea 
cable from CTD to rosette got hung up on cart.

Station 306: 
Pressure hysteresis in CTD 10.

 
C.2  GERARD BOTTLES

Gerard pressures and temperatures were calculated from Deep- Sea
Reversing Thermometer (DSRT) readings.  Each DSRT rack normally
held 2 protected (temperature) thermometers and 1 unprotected
(pressure) thermometer.  Thermometers were read by two people, each
attempting to read a precision equal to one tenth of the
thermometer etching interval.  Thus, a thermometer etched at 0.05
degree intervals would be read to the nearest 0.005 degrees. Each
temperature value is therefore calculated from the average of four
readings provided both protected thermometers function normally.

The temperatures are based on the International Temperature Scale
of 1990.


C.3  SALINITY 
     (George Knapp - WHOI)

Analysis of bottle salinities were performed by two analysts from
WHOI: George Knapp (stations 221-303) and Robert Stanley (stations
304-326).  Methodology for both analyses are described WHOI
Technical Report 90-35.

Guildline Autosal model 8400A salinometers were used during this
cruise.  They were standardized once a day with IAPSO Standard
water, Batch P-114.  During the cruise, Autosal #8 appeared to be
giving erratic readings, due probably to sporadic shipboard radio
interference.  On September 9th, prior to station 247, use of this
salinometer was discontinued and all further samples were run on
Autosal #9.  This salinometer appeared less sensitive to the radio
interference.  Also, salinometer operation was discontinued during
regularly scheduled radio transmissions. Prior to station 304 the
autosal was thoroughly cleaned.  The following table contains
salinity standardization data for the WOCE P16C cruise.

     Batch Sal# Op Tmp  Zero    Sby     Date         Time

STDZE ,P-114,8,GPK,24,-.00002,24+6736,09-01-1991  15:07:47
STDZE ,P-114,8,RJS,24,-.00002,24+6736,09-01-1991  16:27:21
STDZE ,P-114,8,RJS,24,-.00002,24+6736,09-02-1991  10:21:26
STDZE ,P-114,8,RJS,24,-.00002,24+6736,09-03-1991  14:44:10
STDZE ,P-114,8,RJS,24,-.00000,24+6734,09-04-1991  13:24:38
STDZE ,P-114,8,RJS,24,-.00000,24+6727,09-05-1991  12:43:57
STDZE ,P-114,8,RJS,24,-.00000,24+6727,09-06-1991  12:58:31
STDZE ,P-114,8,RJS,24,-.00000,24+6727,09-07-1991  13:20:51
STDZE ,P-114,8,RJS,24,-.00000,24+6726,09-08-1991  13:02:33
STDZE ,P-114,8,RJS,24,-.00000,24+6728,09-09-1991  16:17:39
STDZE ,P-114,9,RJS,24,-.00000,24+6099,09-10-1991  14:04:17
STDZE ,P-114,9,RJS,24,-.00002,24+6099,09-11-1991  13:50:40
STDZE ,P-114,9,RJS,24,-.00002,24+6098,09-12-1991  13:29:16
STDZE ,P-114,9,RJS,24,-.00002,24+6097,09-13-1991  15:47:29
STDZE ,P-114,9,RJS,24,-.00002,24+6098,09-14-1991  08:56:13
STDZE ,P-114,9,RJS,24,-.00002,24+6095,09-15-1991  14:03:03
STDZE ,P-114,9,RJS,24,-.00001,24+6092,09-16-1991  15:15:07
STDZE ,P-114,9,RJS,24,-.00001,24+6089,09-17-1991  15:13:52
STDZE ,P-114,9,RJS,24,-.00001,24+6086,09-18-1991  18:33:48
STDZE ,P-114,9,RJS,24,-.00001,24+6089,09-19-1991  11:54:46
STDZE ,P-114,9,RJS,24,-.00001,24+6089,09-20-1991  14:22:33
STDZE ,P-114,9,RJS,24,-.00001,24+6088,09-21-1991  14:27:12
STDZE ,P-114,9,RJS,24,-.00001,24+6088,09-22-1991  13:32:34
STDZE ,P-114,9,RJS,24,-.00001,24+6089,09-23-1991  14:23:32
STDZE ,P-114,9,GPK,24,-.00001,24+6087,09-24-1991  14:36:32
STDZE ,P-114,9,GPK,24,-.00001,24+6087,09-25-1991  14:25:44
STDZE ,P-114,9,GPK,24,-.00000,24+6087,09-26-1991  15:50:26
STDZE ,P-114,9,GPK,24,-.00001,24+6089,09-27-1991  15:46:47
STDZE ,P-114,9,GPK,24,-.00001,24+6089,09-28-1991  15:52:50
STDZE ,P-114,9,GPK,24,-.00001,24+6087,09-29-1991  16:56:11
STDZE ,P-114,9,GPK,24,-.00001,24+6091,09-30-1991  17:26:43


C.4.    OXYGEN 
        (George Knapp - WHOI)

C.4.a.  DISSOLVED OXYGEN
        Analysts: George Knapp (221-303) and Robert Stanley (304-326).  

No unusual problems were noted.

C.4.b.  NOTE ON CONVERSION TO GRAVIMETRIC UNITS 
        (L.  Gordon, OSU)

The oxygens were converted to gravimetric units by Louis Gordon at
Oregon State University.  The WHPO 91-1 procedures were followed
for the conversions.  Oxygen was converted to micromoles per kg
from the WHOI ml/l data using the densities of the samples computed
at their potential temperatures and salinities.  Where there were
no bottle salinities the CTD salinities were used.   The format for
the oxygen concentration field in the original data file with ml/l
was in the XX.XXX format.  This was changed to to XXX.XX for the
gravimetric units.  This should keep the total number of columns in
the table the same.

In order that the bottle and CTD oxygens in the bottle data file
can be compared, the CTD oxygens were also converted to gravimetric
units by Lou Gordon.  The conversion from ml/l to micromoles/kg was
done using 22.3914 l-STP/mole for the molar volume of oxygen and
seawater density computed using the CTD salinity and potential
temperature at the bottle depths indicated.

C.4.c. This table, from George Knapp, contains all of the Dissolved
Oxygen Standardization and Blank determinations made during WOCE
cruise P-16C.

Mode   Cruise     Burette Vols.     EndVolt   Thio     Date       Time
-----  -----  --------------------  -------  -----  ----------  --------
STDZE  P-16C  15.000  49.879 148.8  0.0210   4.469  09-01-1991  16:06:55
STDZE  P-16C  15.000  49.879 148.8  0.0210   4.491  09-01-1991  16:06:55
STDZE  P-16C  15.000  49.879 148.8  0.0210   4.467  09-01-1991  16:06:55
STDZE  P-16C  15.000  49.879 148.8  0.0210   4.460  09-01-1991  16:06:55
BLANK  P-16C  15.000  49.879 0.999  0.987    0.005  09-01-1991  16:18:03
STDZE  P-16C  15.000  49.879 148.8  0.0140   4.462  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0210   4.466  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0140   4.499  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0140   4.496  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0140   4.478  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0140   4.471  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0210   4.482  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0140   4.473  09-02-1991  12:14:37
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.420  09-03-1991  12:46:59
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.418  09-03-1991  12:46:59
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.426  09-03-1991  12:46:59
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.415  09-03-1991  12:46:59
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.443  09-04-1991  12:22:28
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.437  09-04-1991  12:22:28
STDZE  P-16C  15.000  49.879 148.8  0.0150   4.444  09-04-1991  12:22:28
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.433  09-04-1991  12:22:28
STDZE  P-16C  15.000  49.879 148.8  0.0310   4.469  09-05-1991  13:01:40
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.466  09-05-1991  13:01:40
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.472  09-05-1991  13:01:40
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.465  09-05-1991  13:01:40
BLANK  P-16C  15.000  49.879 1.002  0.992    0.004  09-05-1991  13:13:05
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.493  09-06-1991  12:41:53
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.480  09-06-1991  12:41:53
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.492  09-06-1991  12:41:53
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.482  09-06-1991  12:41:53
STDZE  P-16C  15.000  49.879 148.8  0.0150   4.519  09-07-1991  01:40:05
STDZE  P-16C  15.000  49.879 148.8  0.0150   4.508  09-07-1991  01:40:05
STDZE  P-16C  15.000  49.879 148.8  0.0310   4.237  09-07-1991  14:10:07
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.255  09-07-1991  14:10:07
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.262  09-07-1991  14:10:07
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.256  09-07-1991  14:10:07
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.273  09-08-1991  17:16:51
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.263  09-08-1991  17:16:51
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.274  09-09-1991  14:46:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.268  09-09-1991  14:46:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.272  09-09-1991  14:46:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.263  09-09-1991  14:46:39
BLANK  P-16C  15.000  49.879 1.002  0.992    0.002  09-09-1991  15:13:05
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.280  09-10-1991  13:06:13
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.277  09-10-1991  13:06:13
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.473  09-11-1991  12:59:29
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.463  09-11-1991  12:59:29
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.480  09-11-1991  12:59:29
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.474  09-11-1991  12:59:29
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.483  09-12-1991  13:14:14
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.473  09-12-1991  13:14:14
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.482  09-13-1991  12:55:44
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.483  09-13-1991  12:55:44
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.491  09-13-1991  12:55:44
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.479  09-13-1991  12:55:44
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.510  09-14-1991  14:10:14
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.511  09-14-1991  14:10:14
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.454  09-14-1991  23:12:28
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.448  09-14-1991  23:12:28
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.461  09-14-1991  23:12:28
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.429  09-14-1991  23:12:28
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.498  09-15-1991  15:42:34
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.502  09-15-1991  15:42:34
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.548  09-15-1991  16:00:46
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.542  09-15-1991  16:00:46
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.526  09-15-1991  16:00:46
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.519  09-15-1991  16:00:46
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.555  09-16-1991  15:21:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.560  09-16-1991  15:21:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.557  09-16-1991  15:21:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.556  09-16-1991  15:21:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.555  09-17-1991  15:16:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.554  09-17-1991  15:16:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.562  09-17-1991  15:16:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.557  09-17-1991  15:16:12
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.430  09-18-1991  15:29:11
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.447  09-18-1991  15:29:11
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.441  09-18-1991  15:29:11
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.435  09-18-1991  15:29:11
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.471  09-18-1991  15:29:11
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.467  09-18-1991  15:29:11
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.470  09-19-1991  15:55:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.475  09-19-1991  15:55:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.482  09-19-1991  15:55:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.480  09-19-1991  15:55:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.298  09-20-1991  22:34:37
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.303  09-20-1991  22:34:37
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.312  09-21-1991  15:54:19
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.304  09-21-1991  15:54:19
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.315  09-21-1991  15:54:19
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.304  09-21-1991  15:54:19
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.322  09-22-1991  16:25:04
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.309  09-22-1991  16:25:04
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.320  09-22-1991  16:25:04
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.318  09-22-1991  16:25:04
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.367  09-23-1991  16:12:58
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.354  09-23-1991  16:12:58
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.361  09-23-1991  16:12:58
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.355  09-23-1991  16:12:58
BLANK  P-16C  15.000  49.879 1.002  0.992    0.002  09-23-1991  16:23:05
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.470  09-24-1991  15:35:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.475  09-24-1991  15:35:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.489  09-24-1991  15:35:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.481  09-24-1991  15:35:12
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.288  09-25-1991  22:34:37
STDZE  P-16C  15.000  49.879 148.8  0.0230   4.313  09-25-1991  22:34:37
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.302  09-26-1991  15:59:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.314  09-26-1991  15:59:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.305  09-26-1991  15:59:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.314  09-26-1991  15:59:39
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.322  09-27-1991  16:25:04
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.309  09-27-1991  16:25:04
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.319  09-28-1991  17:21:34
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.325  09-28-1991  17:21:34
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.360  09-29-1991  16:10:00
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.364  09-29-1991  16:10:00
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.364  09-29-1991  16:10:00
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.365  09-29-1991  16:10:00
BLANK  P-16C  15.000  49.879 1.002  0.992    0.000  09-29-1991  16:21:22
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.367  09-30-1991  15:18:33
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.368  09-30-1991  15:18:33
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.364  09-30-1991  15:18:33
STDZE  P-16C  15.000  49.879 148.8  0.0160   4.375  09-30-1991  15:18:33


C.5.    NUTRIENTS 
        (Louis Gordon - Oregon State University)
        22.APR.1992

C.5.a.  EQUIPMENT AND TECHNIQUES:

Nutrient analyses were performed by analysts from Oregon State
University using a Technicon AutoAnalyzer II.  The AutoAnalyzer
used was provided by the Oceanographic Data Facility of Scripps
Institution of Oceanography (ODF/SIO).  A data acquisition system
and the software used to process the nutrient data were developed
and supplied by OSU. For this online document, all Greek letters
have been replaced by similar English alphabet, e.g. umol, and
superscripts put on the same line, e.g. kg-1.

The chemical methods used on Leg 3 (P16C) were essentially and
deliberately the same as those used on the first two legs.  All of
the reagent and standard materials were provided by SIO/ODF.  The
methods are described in Atlas et al. (1972) and Gordon et. al. (in
prep.), but with modifications in analytical protocols as employed
by ODF. Calculation of nutrient concentrations from measured
absorbances was done using OSU software on Leg 3 and SIO/ODF
software on the first two legs.

Several changes in the pump tube sizes used in the AutoAnalyzer
were made at the start of Leg 3. These were made to reduce the
degree of non- linearity in the silicic acid and nitrate + nitrite
(N+N) analyses. The plumbing of the cadmium reduction column used
in the N+N analytical manifold was changed slightly to reduce dead
volume.

C.5.b.  SAMPLING PROCEDURE:

Nutrient samples were drawn from all CTD/rosette casts except for
the 11-bottle ADCP casts made between "regular" CTD casts in the
equatorial region. A total of 89 stations were sampled. Additional
samples were drawn from all Gerard barrels and their "piggyback"
Niskin bottles.  High density polyethylene (HDPE) centrifuge tubes
of approximately 50 ml volume were used as sample containers, and
positioned in the autosampler tray without further sample transfer.
These sample tubes were routinely rinsed at least 4 times with one
third to one half of their volume of sample seawater before
filling.

Nutrient samples were drawn following those for trace gases, He,
Tritium, dissolved oxygen and carbon dioxide.  In some instances,
the complete sampling procedure was not completed for almost 2
hours.  At most stations, the AutoAnalyzer was started before
sampling was completed to reduce the delay and minimize possible
changes in nutrient concentration due to biological processes.
Except for a series of deliberate sample storage experiments, all
analyses were completed within a few hours of the end of the
CTD/rosette casts.

C.5.c.  CALIBRATION AND STANDARDIZATION:

Volumetric labware and the pipettors used to prepare standards were
gravimetrically calibrated in shore laboratories prior to the
cruise.  The Eppindorf Maxipettor adjustable pipettors used to
prepare mixed standards typically have a standard deviation of less
than 0.002 ml on repeated deliveries of 10 ml volumes.  High
concentration mixed standards containing nitrate, phosphate, and
silicic acid were prepared at intervals of 4 to 7 days and kept
refrigerated in HDPE bottles.  At almost every station, a fresh
"working standard" was prepared by adding 20 ml of the high
concentration mixed standard to low nutrient seawater.  A separate
nitrite standard solution was also added to these working
standards.

The pipet and volumetric flask calibrations were rechecked after
the cruise in the OSU lab. Corrections to the preliminary data
computed at sea, based upon the actual volumes of the flasks and
pipettors, have been included in the final data.  These are
systematic, multiplicative corrections which ranged from 0.9987 to
1.003.  Details of these corrections are included as Appendix 1.

The WOCE Operations Manual calls for nutrient concentrations to be
reported in units of micromoles per kilogram (uM kg-1).  Because
the temperature and salinity information required to compute
density is not usually available at the time of initial computation
of the nutrient concentrations, our concentrations are always
originally computed as micromoles per liter.  The unit conversion
has been made using the corrected salinity data for the individual
seawater samples and the monitored, shipboard nutrient laboratory
temperatures.

C.5.d.   ESTIMATION OF PRECISION:

C.5.d.1. SHORT TERM PRECISION:

Throughout the cruise, replicate samples drawn in different sample
tubes from the same Niskin bottle were run at almost every station.
These replicate samples were analyzed both as adjacent samples (one
after the other) and also at the beginning and end of sample runs
to determine if there was deterioration in the samples or
uncompensated instrumental drift.  There was no statistically
significant difference in the reproducibility of replicates
separated by two hours and those run only minutes apart.

Our estimate of the precision obtained within a sample run during
the P16C leg is presented as the average standard deviation of
these replicate analyses are:  Phosphate, 0.014; Nitrate + Nitrite,
0.13; Silicic acid, 0.2; Nitrite, 0.003.  The units are  uM, i.e.
micromoles per liter.

C.5.d.2. LONGER TERM PRECISION:

One of the factors in station-to-station variability of nutrient
analyses is the precision of preparing working standards which have
limited stable lifetimes. Refrigerated, they can be only be stored
for less than six hours to keep deterioration to less than 0.1% for
phosphate, nitrate and silicic acid (see Appendix 2).  A crude
experiment designed to estimate an upper limit to this factor was
performed during about 1/3 of the individual sample runs during the
cruise.  We compared a standard made for the previous station with
the standard freshly prepared for that sample run.

"Leftover" standards were stored in the lab refrigerator until the
following station, and then analyzed as if they were samples. The
working standards are prepared in natural seawater and are not
immune to biological degradation.  Therefore one cannot separate
the effects of precision of preparation from deterioration during
refrigerated storage.

The mean differences between successive working standards,
converted to concentration units ( M): Phosphate, 0.011; Nitrate +
Nitrite, 0.07; Silicic acid, 0.3; Nitrite, 0.011.

C.5.e.   CONVERSION TO GRAVIMETRIC UNITS.

The nutrients were converted from micromolar to micromoles/kg using
densities computed from the sample salinities and the average
nutrient lab temperature, 25.5C.  The maximum range of lab
temperatures was only +/-2.5C so the maximum error introduced by
this scatter is < 0.1%.  Nitrite concentrations have been
subtracted from the nitrate + nitrite concentrations; the nitrate
column heading is now correct and the micromoles/kg unit headings
are now correct.


C.5.f.   APPENDIX 1: NUTRIENTS

Calibration "factors" for P16C WOCE cruise, R/V T.  WASHINGTON,
Sept 1 through Oct 1, 1991.

Preliminary concentrations reported during the cruise have been
corrected by multiplying them by the appropriate calibration
factors.  These are based on gravimetric calibrations of volumetric
flasks and pipets used during the cruise.  Values which are
calculated (as opposed to directly measured) are indicated by
brackets [].  Volumetric flasks are calibrated "to contain".
Pipette tip delivery is defined as total volume delivered.  All
concentrations have units of umoles/liter.

I. Stations 221 - 234

SUMMARY:
Phosphate:            reported concentration * 0.9987
Nitrate plus nitrite: reported concentration * 0.9988
Silicic acid:         reported concentration * 0.9993
Nitrite:              reported concentration * 1.003

                   Phosphate   Nitrate     Silicate   Nitrite
                   ---------   ----------  ---------  ---------
 Formula weight     136.09       101.11     188.072     69
   purity, %        100.00       100.00     100.00     100.00
 grams weighed        0.3402       3.7912     0.4701     0.3451
   [ umoles ]      2499.8      37495.8     2499.6     5001.4
 "A" flask Vol.     999.50       999.50        -      1000.00
["A" std conc.]    2501.1      37514.6         -      5001.4
  Tip delivery       19.977       19.977       -         2.003
 "B" flask Vol.     999.67       999.67     999.67     200
["B" std conc.]      49.98       749.68    2500.40      50.09
  Working Vol.      499.9        499.9      499.9      499.9
Work. tip deliv.     19.979       19.979     19.979     10.007
[ Working conc ]      1.9975      29.961     99.93       1.003
 nominal conc.        2           30.00     100.00       1.00
[calib. factor]       0.9987       0.9987     0.9993     1.0028


Nitrate+Nitrite     30.96
  nominal N+N       31
[calib. factor]     0.9988

II. Stations 235 - 304
      (The pipet tip used for NO3 + PO4 was changed.)

Summary:
Phosphate:         reported concentration * 0.9991
Nitrate + Nitrite: reported concentration * 0.9992
Silicic acid:      reported concentration * 0.9993
Nitrite:           reported concentration * 1.003

                   Phosphate   Nitrate     Silicate   Nitrite
                   ---------   ----------  ---------  ---------
 Formula weight    136.09        101.11     188.072     69
   purity, %       100.00        100        100        100
 grams weighed       0.3402        3.7912     0.4701     0.3451
   [ umoles ]     2499.8       37495.8     2499.6     5001.4
 "A" flask Vol.    999.5         999.5         -      1000
["A" std conc.]   2501.1       37514.6         -      5001.4
  Tip delivery      19.985        19.985       -         2.003
 "B" flask Vol.    999.67        999.67     999.67     200
["B" std conc.]     50.00        749.98    2500.40      50.09
  Working Vol.     499.9         499.9      499.9      499.9
Work. tip deliv.    19.979        19.979     19.979     10.007
[ Working conc ]     1.9983       29.973     99.93       1.003
 nominal conc.       2            30.00     100.00       1.00
[calib. factor]      0.9991        0.9991     0.9993     1.0028
 
Nitrate+Nitrite     30.98
  nominal N+N       31
[calib. factor]     0.9992

III. Stations 305 -  326 (end of cruise)
      (A new tip was used for the working standards)

Summary:
Phosphate:         reported concentration * 0.9996
Nitrate + Nitrite: reported concentration * 0.9996
Silicic acid:      reported concentration * 0.9997
Nitrite:           reported concentration * 1.003

                   Phosphate   Nitrate     Silicate   Nitrite
                   ---------   ----------  ---------  ---------
 Formula weight     136.09       101.11     188.072     69
   purity, %        100          100        100        100
 grams weighed        0.3402       3.7912     0.4701     0.3451
   [ umoles ]      2499.8      37495.8     2499.6     5001.4
 "A" flask Vol.     999.50       999.5         -      1000
["A" std conc.]    2501.1      37514.6         -      5001.4
  Tip delivery       19.985       19.985       -         2.003
 "B" flask Vol.     999.67       999.67     999.67     200
["B" std conc.]      50.00       749.98    2500.40      50.09
  Working Vol.      499.9        499.9      499.9      499.9
Work. tip deliv.     19.987       19.987     19.987     10.007
[ Working conc ]      1.9991      29.986     99.97       1.00
 nominal conc.        2           30.00     100.00       1.00
[calib. factor]       0.9996       0.9995     0.9997     1.003

Nitrate+Nitrite     30.99
  nominal N+N       31
[calib. factor]     0.9996


C.5.g. APPENDIX 2: NUTRIENTS

NUTRIENT SAMPLE STORAGE EXPERIMENTS: P16C

During the latter half of the P16C leg, a series of sample storage
experiments was carried out.  The experiments were motivated by our
observation of apparent instability of some freshly drawn samples
from the first seven stations in the cruise, and by a desire to
evaluate any loss of precision and/or accuracy caused by a delay in
running nutrient samples.  Alcohol (2-propanol), deionized water,
and 10% HCl were used to prerinse the sample tubes prior to
storage.  Replicate sets of samples were stored in a refrigerator
(2 - 5 C) and analyzed after storage for 6 to 24 hours.  Most of
the stored replicates were analyzed within 15 hours of the initial
analysis, and all were analyzed in triplicate.

Twelve experiments consisting of 36 replicate samples each were
done to compare the three different rinsing materials for treating
the sample containers prior to storage.  The seawater test samples
were drawn from shallow, mid-depth, and deep Niskin or Gerard
bottles.  For each experiment, a series of replicate samples was
taken at a normal CTD/rosette station.  The first set of replicates
was analyzed with the routine nutrient samples from the station at
which they originated; the remaining replicates were stored in the
lab refrigerator for the specified times and analyzed with the
samples from subsequent stations.  In all of the storage
experiments, the sample containers used were the same type of 50ml
polyethylene centrifuge tubes which were used for normal sampling
on all three cruise legs according to the ODF protocol.  As a
control, in some of the experiments a set of sample tubes was
rinsed only with the sample seawater (SW), i.e. they received no
other presampling rinse.

In half of the experiments nine sample tubes were rinsed with 10%
HCl, nine with alcohol, nine with DIW, and nine with seawater only.
Twelve of the replicate samples (three of each type of
pretreatment) were analyzed initially, and the remaining replicates
were stored in the lab refrigerator.  The other half of the storage
experiments focused on 10% HCl and alcohol as cleaning media.
Table 1 summarizes the original stations and bottles from which
storage experiment samples were taken and the precleaning media
used in each experiment.


Table 1: Sequence of samples taken from Niskin bottles during P16C 
         for storage experiments.

                RUN  STN  BOTTLE  REPLICATES   WASH
                ---  ---  ------  ----------  -------
                 1   270     7      3+3+3     Alcohol
                 1   270    24      3+3+3     Alcohol
                 1   270    33      3+3+3     Alcohol
                 2   276     7      3+3+3     Alcohol
                 2   276    24      3+3+3     Alcohol
                 2   276    33      3+3+3     Alcohol
                 3   284     7      3+3+3+3   Alcohol
                 3   284    23      3+3+3+3   Alcohol
                 3   284    33      3+3+3+3   Alcohol
                 4   291    33      3+3+3     Alcohol
                 4   291    33      3+3+3     10% HCl
                 4   291    33      3+3+3     DIW
                 4   291    33      3+3+3     SW
                 5   295    34      3+3+3     Alcohol
                 5   295    34      3+3+3     10% HCl
                 5   295    34      3+3+3     DIW
                 5   295    34      3+3+3     SW
                 6   299    22      3+3+3     Alcohol
                 6   299    22      3+3+3     10% HCl
                 6   299    22      3+3+3     DIW
                 6   299    22      3+3+3     SW
                 7   301    22      3+3+3     Alcohol
                 7   301    22      3+3+3     10% HCl
                 7   301    22      3+3+3     DIW
                 7   301    22      3+3+3     SW
                 8   304    23      3+3+3     Alcohol
                 8   304    23      3+3+3     10% HCl
                 8   304    23      3+3+3     DIW
                 8   304    23      3+3+3     SW
                 9   308   G93      3+3+3     Alcohol
                 9   308   G93      3+3+3     10% HCl
                 9   308   G93      3+3+3     DIW
                 9   308   G93      3+3+3     SW
                10   310     6      3+3+3     10% HCI
                10   310    24      3+3+3     10% HCl
                10   310    33      3+3+3     10% HCl
                11   314     7      3+3+3+3   10% HCl
                11   314    22      3+3+3+3   10% HCl
                11   314    32      3+3+3+3   10% HCl
                12   317     7      3+3+3     10% HCI
                12   317    22      3+3+3     10% HCl
                12   317    32      3+3+3     10% HCI
   
                Note: G93 is Gerard bottle No. 93. All 
                      other bottle number represent 
                      Niskin samples. 


The following observations can be made:

1.  There were no clear trends of monotonic increases or decreases
    in nutrient concentration versus time of storage or cleaning
    method.

2.  For all of the precleaning methods used, many of the stored
    replicates had mean concentrations which differed from the initial
    concentration.  These differences were often greater than our
    estimates of long and short term precision and were evident after
    as little as six hours of storage (Figures C.5.1-4).

3.  Most of the stored replicates had mean concentrations which
    were within q0.03 M (phosphate), q0.40 M (N+N), q1.5 M (silicic
    acid), and q0.02 M (nitrite) of their original concentrations.
    These ranges are roughly q1 % of the maximum concentrations
    encountered in the water column, the desired and specified WOCE
    analytical precision.  (Note that in many cases the variances of
    the stored samples comprise a significant fraction of, or exceed,
    this specification.)

4.  In general, precleaning of sample tubes seems preferable to no
    treatment: the precision of triplicate determinations from
    precleaned sample tubes was better than for uncleaned tubes.

5.  In this experiment virtually all of the stored sample sets
    exhibited considerably higher variance than the unstored samples.
    The stored variances were on order of twice or more than the
    variances of the original, unstored samples.  Although this
    experiment applies only to the sample tubes and seawater samples
    used therein it is perhaps indicative of more general cases.
    Obviously, this experiment cannot resolve the effects of
    refrigerated storage times of less than six hours but it clearly
    indicates that storage times of this length or more can markedly
    degrade analytical precision.

Figures C.5.1-4 present the results of the storage experiments as
departures from the means of measured concentrations of unstored
samples, for each nutrient and for each precleaning method, as
functions of storage times.

NUTRIENT QC NOTES: P16C Cruise

During the P16C cruise, the WHPO data editing program "Q1EDIT" was
used to perform a first pass QC check on the nutrient data,
primarily by comparing vertical profiles and nutrient/theta
relationships.  The version of Q1EDIT which was available on the
cruise could only changes data quality flags from "2" (acceptable)
to "3" (questionable).  Following the cruise, all nutrient data
were rechecked based on notes made while at sea and on plots
produced in the laboratory.  Some correctable errors were found and
the appropriate corrections made.  At this time, the data quality
flags were edited to conform to the definitions in the WOCE
Operations Manual (WOCE Report No. 67/91). Data quality flags were
assigned as follows:

  Quality 
   byte   Definition
  ------- ------------------------------------------------------
    2     Acceptable measurement
    3     Questionable measurement; no obvious problems found, 
              but data somewhat out of trend.
    4     Bad measurement; known analytical problems or data
              seriously out of trend.
    9     Sample not drawn, usually due to Niskin bottle failure


At several stations, the bottle tripping order was deliberately (or
accidentally) different from 1-36. At the end of the cruise, some
of the data files did not include the correct bottle order which
led to errors in some of the preliminary QC notes.  The following
notes apply to a list of QC comments prepared by the Chief
Scientist (Lynne Talley) during the cruise.  We have abbreviated
phosphate as "P", nitrate + nitrite as "N+N".

STATION 236/01:
Talley noted problems with P & N+N in bottles 2, 4, and 10; and that
bottle 11 was a leaker. The actual bottle tripping sequence was 25
through 36 and then 1 through 24.  The problems with P and N+N were
actually in bottles 26 and 28 (vs 2 & 4), and the leaker was 35.

We think nutrients in bottle 34 (10 in Talley's notes) are OK and
the quality bytes should be 2.  On the other hand, bottle 33
(Talley's 9) did have P and N+N problems.  (Note from Talley:
the WHOI software did not permit the actual bottle numbers to be
placed in the bottle data file, so positions 2 and 4 in that file
are the ones with problems.  There is now no flag on position 10;
position 9 is flagged.)

STATION 260/01:
The actual bottle tripping sequence was 25 through 36, then 1
through 24.  The leaker was 2 and not 14. Therefore, the logbook is
correct in saying that bottle 2 was a leaker.  File 0260A001.nut
had the bottle numbers in the wrong order at the end of the cruise.
They  have been corrected in our current 0260A001 file.  (Note from
Talley: again the WHOI software did not permit the actual
bottle numbers to be placed in the bottle data file, so position 14
in that file is the leaker.  As Gordon notes, this was actually
bottle 2, which is why there is a note to that effect in the data
quality file  - section D below.)

STATION 289/01:
Bottle 19 vs. bottle 29.  In file 0289A001.nut there are two
bottles identified as 29.  The first one corresponds to sequential
number 19, thus we assume this was indeed bottle 19 and not 29. The
second bottle 29 has a sequence Nr.  of 29.  Nutrient data for the
first bottle 29 (actually 19) look OK for the corresponding depth.

STATION 292/01:
The actual bottle tripping sequence was 25-36 and 1-24.  Bottle 32
rather than 8 was the leaker. (Note from Talley: here the
bottle numbers are correct in the bottle file: so bottle 32 in
position 8 was a leaker.)

STATION 319/01:
Checked deep N+N; it seems to agree with adjacent stations. Talley 
had it flagged as "3".  We think it should be assigned quality
bytes of "2".  (Note from Talley: this flag was changed back
to 2.)

C.5.h.  CHIEF SCIENTIST COMMENTS ON NUTRIENT MEASUREMENTS
        (Lynne D. Talley)

As noted in the cruise report portion of this text, there were
problems with nitrate and phosphate on P16C. The following is an
updated version of the text found in section A.5:

Difficulties were encountered with some nitrate and phosphate
analyses on stations 226 to 244.  Replicate samples using different
sample tubes and water out of different Niskins indicated that the
problem was with some of the sampling tubes used to collect water
from the rosette sampler.  All tubes were thoroughly cleaned with
HCl before sta. 245, solving the problem, thus suggesting that
biological fouling coupled with an absence of regular cleaning was
the problem. Most of the nutrients from the affected stations are
acceptable. With the exception of occasional random problems and
problems with nitrate at stations 256 and 258, all data from
stations 221-225 and 246-326 are acceptable. To compare with
silica, which was excellent throughout the cruise: there were a
total of 6 flagged questionable or bad silicas, 101 flagged
phosphates, and 170 flagged nitrates, out of a total of 3273 water
sample levels.

In an attempt to ensure that nutrient data from all three WOCE legs
would be compatible despite the different lead analysis groups, the
same equipment and standards were used on all three legs.  Silica
and phosphate values from legs 2 and 3 are consistent with each
other.  However, nitrate on leg 3 is systematically 1-2 mu
moles/liter higher than on leg 2.



C.6.  CARBON SYSTEMS 

Abstracted from NDP-060 

Goyet, Catherine, Peter R. Guenther, Charles D. Keeling, and Lynne D. Talley. 
                                     1996.
       Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the
      R/V Thomas Washington Cruise TUNES-3 in the Equatorial Pacific Ocean

                                                          (WOCE section P16C). 
                                                      ORNL/CDIAC-96,  NDP-060.  
                                   Carbon Dioxide Information Analysis Center, 
                                                Oak Ridge National Laboratory, 
                                                         Oak Ridge, Tennessee.


SUMMARY

This data documentation discusses the procedures and methods used to obtain 
total carbon dioxide (TCO2), total alkalinity (TALK), hydrographic, and 
chemical data during the Research Vessel Thomas Washington Expedition TUNES-3 
in the Equatorial Pacific Ocean (Section P16C). Conducted as a part of the 
World Ocean Circulation Experiment (WOCE), the cruise began in Papeete, Tahiti, 
on August 31, 199 1, and finished in Honolulu, Hawaii, on October 1, 199 1. 
WOCE Meridional Section P16C along 150 W and between 18 S and 19 N was 
completed during the 31-day expedition. All 105 hydrographic and 8 large-volume 
stations were completed to the full water column depth. Station spacing was 30 
nautical miles (nm), except between 3 N and 3 S where it was 10 nm. Twenty-
five bio-optics stations were sampled for the Joint Global Ocean Flux Study, 
and at 21 stations carbon dioxide measurements were provided for the U.S. 
Department of Energy's CO2 program. Hydrographic and chemical measurements made 
along WOCE Section P16C included pressure, temperature, salinity, and oxygen 
measured by conductivity, temperature, and depth sensor; and bottle salinity, 
oxygen, phosphate, nitrate, nitrite, silicate, chlorofluorocarbon (CFC-11, CFC-
12, TC02, and TALK. In addition, potential temperatures were calculated from 
the measured variables.

The TC02 concentration in 652 seawater samples was determined by semi-automated 
coulometry using, an improved version of the instrument earlier described by 
Johnson et al., (1985, 1987). The precision of these measurements was estimated 
to be better than 0.01%. The desired accuracy was better than 4 mol/kg.
The TALK concentration in 539 seawater samples was determined by a 
potentiometric acid titration system that was designed and constructed at the 
Scripps Institution of Oceanography (SIO) by David Moss and Timothy Lueker 
(Guenther et al. 1994a).

Seventy-one replicate samples were also collected for later shore-based 
reference analyses of TC02 and TALK by vacuum extraction and manometry in the 
laboratory of C. D. Keeling of SIO.

The data set is available, free of charge, as a numeric data package (NDP) from 
the Carbon Dioxide Information Analysis Center. The NDP consists of two 
oceanographic data files, two FORTRAN 77 data-retrieval routine files, a 
documentation file, and this printed report, which describes the contents and 
format of all files and the procedures and methods used to obtain the data.

Keywords: carbon dioxide; total alkalinity; World Ocean Circulation Experiment 
          (WOCE); Pacific Ocean; hydrographic measurements; carbon cycle


C.6.1. BACKGROUND INFORMATION

The World Ocean plays a dynamic role in the Earth's climate: it captures heat 
from the sun, transports it, and releases it thousands of miles away. These 
oceanic- solar-atmospheric interactions affect winds, rainfall patterns, and 
temperatures on a global scale. The oceans also play a major role in global 
carbon-cycle processes. Carbon is unevenly distributed in the oceans because of 
complex circulation patterns and biogeochemical cycles, neither of which is 
completely understood, as well as the biological processes of photosynthesis 
and respiration. The oceans are estimated to hold 38,000 gigatons of carbon, 50 
times more than that in the atmosphere and 20 times more than that held by 
plants, animals, and the soil. If only 2% of the carbon stored in the oceans 
were released, the level of atmospheric carbon dioxide (C02) would double. 
Every year, more than 15 times as much C02 is exchanged across the sea surface 
than the amount produced by burning of fossil fuels, deforestation, and other 
human activities (Williams 1990).

To better understand the ocean's role in climate and climatic changes, several 
large experiments have been conducted, and others are under way. The largest 
oceanographic experiment ever attempted is the World Ocean Circulation 
Experiment (WOCE). A major component of the World Climate Research Program, 
WOCE brings together the expertise of scientists and technicians from more than 
30 nations. In the United States, WOCE is supported by the federal government 
under the Global Change Research Program. The multi-agency U.S. effort is led 
by the National Science Foundation and is supported by major contributions from 
the National Oceanic and Atmospheric Administration, the U.S. Department of 
Energy (DOE), the Office of Naval Research, and the National Aeronautics and 
Space Administration. Although total carbon dioxide (TCO2) is not an official 
WOCE measurement, a coordinated effort, supported in the United States by DOE, 
is being made on WOCE cruises (through 1998) to measure the global, spatial, 
and temporal distributions of TC02 and other carbon-related parameters. The 
goal of the C02 survey includes estimation of the meridional transport of 
inorganic carbon in the Pacific Ocean in a manner analogous to the oceanic heat 
transport (Bryden and Hall 1980; Brewer et al. 1989; Roemmich and Wunsch 1985), 
evaluation of the exchange of C02 between the atmosphere and the ocean, and 
preparation of a database suitable for carbon-cycle modeling and the subsequent 
assessment of the anthropogenic C02 increase in the oceans. The final data set 
is expected to cover -23,000 stations.

This report presents C02-related measurements obtained during, the 3 1 -day Leg 
3 of the Research Vessel (RN) Thomas Washington TUNES Expedition (TUNES-3) 
along the WOCE zonal Section P16C, which is located in the equatorial part of 
the Pacific Ocean along the 150 W meridian, between 17.5 S and 19.0 N (Fig. 
1).

The C02 investigation during the TUNES-3 Expedition was supported by a grant 
(No. DEFG02-90-ER60983) from DOE.


C.6.2 TOTAL C02 MEASUREMENTS

During the TUNES-3 Expedition, 652 samples were analyzed for TC02 
concentrations in seawater. The sampling frequency for measurements of the 
carbonate parameters was reduced to a complete depth profile (36 samples) ~ 
every fourth hydrographic station (Fig. 2). This reduction was implemented not 
according to any prearranged geophysical criterion but to accommodate the time 
constraints for two analysts on board to perform C02 sampling and measurements. 
In other words, the adopted C02 sampling strategy was to measure as many 
samples as was technically and humanly possible.

For TC02 measurements, the seawater samples were drawn into 500-mL borosilicate 
glass bottles equipped with Rodaviss joint closure systems, poisoned with 100 
L of a saturated solution of mercuric chloride (HgCl), and analyzed on board 
generally within 18 h. TC02 concentration was measured by semi-automated 
coulometry using an improved version of the instrument earlier described by 
Johnson et al. (1985, 1987) and calibrated using the procedure described in 
Goyet and Hacker (1992). This early "SOMMA-type" system did not have gas loops 
for calibration. Consequently, plans were to calibrate the system with standard 
solutions as described in Goyet and Hacker (1992); however, uncontrollable 
events (i.e., a hurricane occurred in Woods Hole a few days before the cruise) 
destroyed standard solutions that were prepared for the cruise. As a result, 
the certified reference materials (CRMs) were used as standards to calibrate 
the TC02 extraction/coulometer system. Precision of the measurements was 
estimated to be better than 0.01%; the desired accuracy was better than 4 
mo/kg (Goyet et al. 1995). The automated coulometric system forced the sample 
into the pipet using a pressurized headspace gas. Pure nitrogen (N2) headspace 
gas was used for standard solution measurements, and C02 headspace gas (290 ppm 
in air) was used for seawater sample measurements. The volume of the pipet was 
calibrated with distilled water and seawater (volume was -30 mL, depending on 
the individual pipet used), and there was no significant difference in the 
delivery volume as a result of possible differences in surface tension at 
different salinities. The sample was drained from the pipet into a stripper 
containing 1.5 mL of 8.5% phosphoric acid.

This chamber and the added acid were purged of any CO2 with pure N2 carrier gas 
before the sample was added. In the stripper, the C02 gas was extracted from 
the acidified sample by a continuous flow of pure N2 gas through a frit at the 
bottom of the stripper. The gas (mainly C02, N2 and water vapor) was passed 
through a condenser thermostated with 4C water and magnesium perchlorate 
[Mg(Cl04)] to remove water vapor. It was then passed through silica gel to 
remove residual aerosols and traces of hydrogen sulfide (H2S) and phosphoric 
acid (H3PO4) before being bubbled into a commercially available coulometric 
solution containing ethanolamine [NH2(CH2)20H], dimethyl sulfoxide [(CH3)2SO], 
and thymolphthalein dye (made by UIC, Inc., Joliet, IL, USA). A coil made from 
glass tubing with thermostated water flowing through it was placed in the cell 
to maintain the solution at 24C. The pH of the solution was monitored on an 
UIC, Inc., total C02 coulometer by monitoring the thymolphthalein-absorbance 
indicator at -610 nm. Hydroxide (-OH) ions were generated by the coulometer 
circuitry to maintain absorbance of the solution at a constant value. The 
analytical procedure was controlled by a microcomputer that also recorded the 
coulometric titration and computed the total CO2 extracted from the sample 
based on the amount of OH- generated to reach the end point.

Figure 3 summarizes the analytical results as a contour section plot of the 
TCO2, data from the WOCE Section P16C along -150 W. 

C.6.3 TOTAL ALKALINITY MEASUREMENTS

To determine the TALK concentration in seawater, 539 samples were titrated. 
Typically, 28 of the 36 samples from Niskin bottles collected on a station were 
analyzed during the cruise. The TALK was measured on aliquot of seawater taken 
from the same 500-mL bottle previously analyzed for TC02. Duplicate samples 
were collected on six stations and analyzed for TALK. The closed-cell 
potentiometric acid titration system was used to determine TALK concentration. 
The system was designed and constructed at SIO by David Moss with the 
developmental and experimental assistance of Timothy Lueker. A full description 
of TALK measurements is provided in Guenther et al. (1994a).

C.6.4 SHORE-BASED REPLICATE MEASUREMENTS

The replicate samples from 100 Niskin bottles at 18 stations were collected for 
shore-based reference analyses at the laboratory of C. D. Keeling of SIO. The 
TC02 measurements were produced by vacuum extraction/manometric analysis and 
the TALK values by potentiometric titration. Both measurements were performed 
under controlled laboratory conditions using standards. The replicate sample 
standard deviation (s) for this large data set of 71 unflagged pairs is 1.0 
mol/kg after omitting the three replicate pairs with deltas greater then 3s (a 
replicate sample standard deviation calculated from the set of analyses on 
duplicate samples) (Guenther et al. 1994b).

Substantial reduction in the calculated s of the ship-minus- shore comparison 
is made by omitting 24 comparisons of singlet replicate samples, plus 5 more 
that are greater than 3s for either the replicate pairs or the comparison 
difference. For the 66 remaining comparisons, the average ship-minus-shore 
difference is -2.12.4 mol/kg (Guenther et al. 1994b). Figure 4 shows the 
ship-minus-shore differences for all available surface and deep data from the 
TUNES-3 Expedition. The plotted data indicate a bias for surface data relative 
to deep data; surface data show better agreement between shipboard and shore-
based data than do deep data.


C.6.5. DATA CHECKS AND PROCESSING PERFORMED BY CDIAC

An important part of the NDP process at the Carbon Dioxide Information Analysis 
Center (CDIAC) involves the quality assurance (QA) review of data before 
distribution. Data received at CDIAC are rarely in a condition that permits 
immediate distribution, regardless of the source. To guarantee data of the 
highest possible quality, CDIAC conducts extensive QA reviews that involve 
examining the data for completeness, reasonableness, and accuracy. Although 
they have common objectives, these reviews are tailored to each data set and 
often require extensive programming efforts. In short, the QA process is a 
critical component *in the value-added concept of supplying accurate, usable 
data for researchers.

The following information summarizes the data-processing and QA checks 
performed by CDIAC on the data obtained during the R/V Thomas Washington TUNES-
3 Expedition in the South Pacific Ocean (WOCE Section P16C).

1.  Carbon-related data and preliminary hydrographic measurements were provided 
    to CDIAC by Catherine Goyet of WHOI and Peter Guenther and Dave Keeling of 
    SIO. Hydrographic measurements and the station information files were 
    provided by Lynne Talley of SIO and by the WOCE Hydrographic Program Office 
    after quality evaluation. A FORTRAN 77 retrieval code was written and used 
    to merge and reformat all data files.

2.  The designation for missing values, given as "-9.0" in the original files, 
    was changed to 11-999.9.11

3.  To check for obvious outliers, all data were plotted with a PLOTNEST.C , 
    program written by Stewart C. Sutherland (LDEO). The program plots a series 
    of nested profiles, using the station number as an offset; the first station 
    is defined at the beginning, and subsequent stations are offset by a fixed 
    interval (Figs. 5 and 6). Several outliers were identified and removed after 
    consultation with the principal investigators. 

4.  To identify "noisy" data and possible systematic, methodological errors, 
    property-property plots for all parameters were generated (Fig. 7), 
    carefully examined, and compared with plots from previous expeditions in the 
    South Pacific Ocean.

5.  All variables were checked for values exceeding physical limits, such as 
    sampling depth values that are greater than the given bottom depths.  6. 
    Dates and times were checked for bogus values (e.g., values of MONTH < I or 
    > 12, DAY < I or > 3 1, YEAR < or > 199 1, TIME < 0000 or > 2400).

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



C.6.6. REFERENCES

Atlas, E. L., S. W. Hager, L. I. Gordon, and P. K. Park. 197 1. A Practical 
    Manual for Use of the Technicon@ in Seawater Nutrient Analyses; rev. 
    Technical Report 215, Refs. 71-22, Oregon State University, Dept. of 
    Oceanography, Oregon.   Brewer, P. G., C. Goyet, and D. Dyrssen. 1989. 
    Carbon dioxide transport by ocean currents at 25 N latitude in the Atlantic 
    Ocean. Science 246:477-79.

Bryden, H. L., and M. M. Hall. 1980. Heat transport by ocean currents across 25' 
    N latitude in the North Atlantic Ocean. Science 207:884.

Carpenter, J. H. 1965. The Chesapeake Bay Institute technique for the Winkler 
    dissolved oxygen method. Limnol. & Oceanogr. 10: 141-43.

Culberson, C. H., and R. T. Williams. 1991. A comparison of methods for the 
    determination of dissolved oxygen in seawater. WHP Office Report, WHPO 91- 
    2. Woods Hole Oceanographic Institution, Woods Hole, Massachusetts.

Goyet, C., and S. D. Hacker. 1992. Procedure for calibration of a coulometric 
    system used for total inorganic carbon measurements of seawater. Mar. Chem. 
    38:37-51.

Goyet, C., D. Davis, E. T. Peltzer, and P. G. Brewer. 1995. Development of 
    improved space sampling strategies for ocean chemical properties: Total 
    carbon dioxide and dissolved nitrate. Geophysical Research Letters, 
    22(8):945-48.

Guenther, P. R., G. Emanuele III, D. J. Moss, T. J. Lueker, and C. D. Keeling. 
    1994a. Oceanic C02 Measurements for the WOCE Hydrographic Survey in the 
    Pacific Ocean: Shipboard Alkalinity Measurements on TUNES Leg 3, 1991. SIO 
    Reference Series, Ref. No. 94-29. University of California, San Diego.

Guenther, P. R., C. D. Keeling, and G. Emanuele III. 1994b. Oceanic C02 
    Measurements for the WOCE Hydrographic Survey in the Pacific Ocean, 1990-
    1991: Shore Based Analyses. SIO Reference Series, Ref. No. 94-28. University 
    of California, San Diego.

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

Johnson, K. M., J. M. Sieburth, P. J. Williams, and L. Brandstrom. 1987. 
    Coulometric total carbon dioxide analysis for marine studies: automation and 
    calibration. Mar. Chem. 21:117-33.

Kester, D. R. 1975. Dissolved gases other than C02 pp. 498-556. P. Riley and G. 
    Skirrow (eds.), In Chemical Oceanography, Vol. 1J. Academic Press, London.

Roemmich, D., and C. Wunsch. 1985. Two transatlantic sections: Meridional 
    circulation and heat flux in the subtropical North Atlantic Ocean. Deep-Sea 
    Res. 32:619-64.

UNESCO. 1981. Background Papers and Supporting Data on the Practical Salinity 
    Scale, 1978. UNESCO Technical Papers in Marine Science, No. 37, 144 pp.

Williams, P. J. 1990. Oceans, Carbon, and Climate Change. Scientific Committee 
    on Oceanic Research (SCOR), Halifax, Canada. 



C.7     CHLOROFLUOROCARBONS 
        (John Bullister - NOAA/PMEL)

C.8     TRITIUM 
        (William Jenkins - WHOI)   

C.9     SHALLOW HELIUM-3 
        (William Jenkins - WHOI)   

C.10    DEEP HELIUM-3  
        (Harmon Craig - SIO)  
 


D.      ACKNOWLEDGMENTS

The collection of WOCE data along P16C was supported by a number of
individual grants from the National Science Foundation's Ocean
Sciences Division.  All of us especially thank Captain T.
Desjardins and the crew of the R/V T. Washington for their
excellent support of our work.



E.      REFERENCES

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

Gordon, L.I., J.C. Jennings, Jr., A.A. Ross and J.M.  Krest,
    submitted December 1993.  A suggested protocol for continuous flow
    automated analysis of seawater nutrients (Phosphate, nitrate,
    nitrite and silicic acid) in the WOCE Hydrographic Program and the
    Joint Global Ocean Fluxes Study.   WOCE Operations Manual, Part
    3.1.3: WOCE Operations and Methods, WOCE Hydrographic Program
    Office Report WHPO 91-1, unpublished manuscript.

Gordon, L. I., J. Krest, A. A. Ross, in preparation. A technique
    for reducing the laboratory temperature sensitivity of continuous
    flow analysis of silicic acid in seawater.

Knapp, G.P., M.C. Stalcup and R.J. Stanley, 1990. Automated Oxygen
    Titration and Salinity Determination.  WHOI Technical Report
    WHOI-90-35, 25pp.

Lupton, J.E. and H. Craig, 1981.  A major helium-3 source at 15S on
    the East Pacific Rise.  Science, 214, 13-18.

Mangum, L., J. Lynch, K. McTaggart, L. Stratton, S.  Hayes, 1991.
    CTD/O2 data measurements collected on TEW (Transport of Equatorial
    Waters) June-August 1987.  NOAA Data Report ERL PMEL-33.  375 pp.

Speer, K.G., 1989.  The Stommel and Arons model and geothermal
    heating in the South Pacific.  Earth and Planet. Sci. Lett., 95,
    359-366.

Taft, B.A. and P. Kovala, 1981.  Vertical sections of temperature,
    salinity ,thermosteric anomaly and zonal geostrophic velocity from
    Norpac shuttle experiment: Part I.  NOAA Data Report ERL PMEL-3.

Wyrtki, K. and B. Kilonsky, 1984.  Mean water and current structure
    during the Hawaii-to-Tahiti shuttle experiment. J. Phys.
    Oceanogr., 14, 242-253.



F.      BOTTLE DATA COMMENTS AND FLAGGING 
        (Lynne Talley - SIO)

For each discrete data point which has a flag other than "2", brief
information is provided herein indexed by station number, bottle,
sample, flag, CTD pressure, and CTD theta.  Included also are
sampling comments regarding potentially leaking bottles, even if
the analyses appeared normal, in the event that a future analysis
of a different chemical should show an irregularity.

Final revision: 7/25/95 LDT following comparison with CTD data.

bqflg refers to the WHP bottle quality flag.  qflg refers to the
WHP water sample quality flag.


NOTES ON USE OF FLAGGED BOTTLE DATA:

1. Data with qflg .ne. 2 or with bqflg .ne. 2 should not be used.
   The flag 3 for data usually means there is a serious problem but
   the reason for the problem is unknown.

2. Nutrients were not collected on the odd numbered stations 251 -
   283 inclusive.

3. Some nitrite flags may not be commented on: whenever both
   nitrate and phosphate are flagged, nitrite usually is also flagged.
   One of the indications of the pervasive nitrate, phosphate problem
   from stas. 226 to 244 was high nitrite deep in the water column.
   Deep nitrites greater than or equal to .02 were flagged.  Negative
   nitrites (all -.01 and most on station 258) were not flagged and
   are assumed to be 0.0.

221/01: 13    bqflg=2 qflg=4 oxygen. sampling error.
        11    bqflg=2 qflg=3 po4 (probably tube problem)

222/01:  1    bqflg=2 qflg=9 salinity - empty sample bottle
         2    bqflg=2 qflg=2 leak (log sheet). no action
        26    bqflg=2 qflg=2 leak (log sheet).  no action
        29    bqflg=2 qflg=2 possible O2 bubble.  no action

223/01:  1    bqflg=2 qflg=2 leaking at bottom (log sheet). no action
         1    bqflg=2 qflg=3 po4 sampling tube problem
         4    bqflg=2 qflg=4 oxygen sampling error
         4    bqflg=2 qflg=3 salinity .004 too high. no reason
         5    bqflg=2 qflg=4 oxygen sampling error
         6    bqflg=2 qflg=4 oxygen sampling error
        10    bqflg=2 qflg=3 no3 sampling tube problem
        10    bqflg=2 qflg=3 po4 sampling tube problem
        11    bqflg=2 qflg=3 po4 sampling tube problem
              Note: CTD pressure sequencing resulted in pressure
                    of 4117 for bottle 1 and 4120 for bottle 2.  The
                    maximum pressure in the CTD file is 4117.  Bottle 2
                    was actually fired about 10 m above bottle 1.  I don't
                    know why bottle 2 shows a higher pressure.
                    No change to the pressure flags was made, but it
                    might be at some later time.

224/01:  1    bqflg=2 qflg=2 leaking at bottom. no action
         2    bqflg=2 qflg=3 po4 sampling tube problem
         7    bqflg=2 qflg=3 salinity problem - no reason
         8    bqflg=2 qflg=3 salinity problem - no reason
         9    bqflg=2 qflg=4 Salinity noise - no reason.
                              no nutrients reported (no reason)
        11    bqflg=2 qflg=3 salinity problem - no reason
        21    bqflg=2 qflg=3 salinity problem - no reason
        22    bqflg=2 qflg=3 salinity problem - no reason
        23    bqflg=2 qflg=3 salinity problem - no reason
        24    bqflg=2 qflg=3 salinity problem - no reason
        25    bqflg=2 qflg=3 salinity problem - no reason
        26    bqflg=2 qflg=3 salinity problem - no reason

225/02: 13    bqflg=2 qflg=4 oxygen high .05 - no reason
        14    bqflg=2 qflg=2 salinity looks low relative to CTD
                             cast 5, but no apparent reason to flag it.

225/05:  1    bqflg=2 qflg=3 po4 sampling tube problem
         4    bqflg=2 qflg=4 salinity problem - no reason

226/01: 11    bqflg=2 qflg=4 nitrate, phosphate sampling tube problem
        20    bqflg=2 qflg=2 leak. no action
        27    bqflg=2 qflg=2 leak. no action
        29    bqflg=2 qflg=2 leak. no action

227/01:  3    bqflg=2 qflg=4 oxygen sampling error
        11    bqflg=2 qflg=4 nitrate, phosphate sampling tube problem

228/01: 11    bqflg=2 qflg=4 nitrate, phosphate sampling tube problem

229/01:  8    bqflg=4 qflg=5 all. empty
        11    bqflg=2 qflg=4 nitrate, phosphate sampling tube problem
        13    bqflg=2 qflg=4 nitrate, phosphate sampling tube problem
        18    bqflg=2 qflg=2 nitrate, phosphate - checked and looks OK ldt
        25    bqflg=2 qflg=4 salinity problem - no reason

230/01: 1-7   bqflg=2 qflg=5 nitrate not reported (analytical problem)
        10    bqflg=2 qflg=3 phosphate sampling tube  problem
        11    bqflg=2 qflg=4 nitrate,phosphate sampling tube problem
        12    bqflg=2 qflg=3 nitrate sampling tube problem
        13    bqflg=2 qflg=4 nitrate,phosphate sampling tube problem

        18    bqflg=2 qflg=2 nitrate, phosphate - checked and looks OK ldt
        24    bqflg=2 qflg=2 nitrate, phosphate - checked and looks OK ldt

231/01: 1-33  bqflg=2 qflg=3 all nitrites - no reason
        10    bqflg=2 qflg=4 nitrate, phosphate problem
        11    bqflg=2 qflg=4 nitrate, phosphate problem
        12    bqflg=2 qflg=4 nitrate, phosphate problem
        13    bqflg=2 qflg=4 nitrate, phosphate problem
        15    bqflg=2 qflg=4 nitrate, phosphate problem
        18    bqflg=2 qflg=4 nitrate, phosphate problem
        24    bqflg=2 qflg=4 nitrate, phosphate problem
        25    bqflg=2 qflg=4 phosphate problem
        26    bqflg=2 qflg=3 nitrate, phosphate problem
        32    bqflg=2 qflg=2 vent open. no action.

232/01:  1    bqflg=2 qflg=3 salinity problem - no reason
         7    bqflg=2 qflg=3 salinity problem - no reason
        10    bqflg=2 qflg=3 salinity problem - no reason
              bqflg=2 qflg=4 nitrate, phosphate problem
        11    bqflg=2 qflg=4 nitrate, phosphate problem
        12    bqflg=2 qflg=3 salinity problem - no reason
              bqflg=2 qflg=4 nitrate, phosphate problem
        13    bqflg=2 qflg=4 nitrate, phosphate, nitrite problem
        14    bqflg=2 qflg=4 nitrate, phosphate problem
        15    bqflg=2 qflg=4 nitrate, phosphate problem
        18    bqflg=2 qflg=4 nitrate, phosphate, nitrite problem
        19    bqflg=2 qflg=3 nitrate, phosphate

233/01:  2    bqflg=2 qflg=3 salinity problem - no reason
         7    bqflg=4 qflg=9 empty (stopcock broken off)
        10    bqflg=2 qflg=4 nitrate, phosphate,nitrite problem
        11    bqflg=2 qflg=4 nitrate, phosphate,nitrite problem
        12    bqflg=2 qflg=4 nitrate, phosphate,nitrite problem
        13    bqflg=2 qflg=4 nitrate, phosphate,nitrite problem
        14    bqflg=2 qflg=3 salinity problem - no reason
        15    bqflg=2 qflg=4 nitrate, phosphate,nitrite problem
        18    bqflg=2 qflg=4 nitrite very high - tube problem
        19    bqflg=2 qflg=3 nitrate, phosphate,nitrite problem
        21    bqflg=2 qflg=4 nitrate, phosphate problem
        22    bqflg=2 qflg=3,4 nitrate, phosphate,nitrite problem
        25    bqflg=3 qflg=4 all. Leaker, noted on log sheet.

234/01: 2     bqflg=3 qflg=4 all. Leaker, noted on log sheet.
        10    bqflg=2 qflg=4 salinity .01 too high - no reason.
              bqflg=2 qflg=4 phosphate problem.
        12    bqflg=2 qflg=4 phosphate problem.
        13    bqflg=2 qflg=4 phosphate problem.
        16-25 bqflg=4 qflg=5 all. empty
        26    bqflg=3 qflg=4 all. Leaker, not indicated on sample log.
        32    bqflg=2 qflg=2 leak (log sheet). no action
        35    bqflg=2 qflg=2 leak (log sheet). no action

235/04: 12    bqflg=2 qflg=4 nitrate, phosphate problem.
        27    bqflg=2 qflg=2 potential leaker (log sheet). no action
        32    bqflg=2 qflg=2 potential leaker (log sheet). no action

236/01: 2     bqflg=2 qflg=3 nitrate, phosphate problem.
        4     bqflg=2 qflg=3 nitrate, phosphate problem.
        9     bqflg=2 qflg=4 nitrate, phosphate problem.
        11    bqflg=3 qflg=4 all. Leaker, not noted on sample log sheet. 
              The actual bottle tripping sequence was 25 through 36 and
              then 1 through 24, but the WHOI software did not permit the 
              actual bottle numbers to be entered in the sea file.

237/01: 2     bqflg=3 qflg=4 all. Leaker, not noted on sample log.
        10    bqflg=2 qflg=4 nitrate, phosphate problem.
        11    bqflg=2 qflg=4 nitrate, phosphate problem.
        12    bqflg=2 qflg=4 nitrate, phosphate problem.
        15    bqflg=2 qflg=3 nitrate, phosphate problem.

238/01: 8     bqflg=2 qflg=4 salinity .01 too high - no reason
        10    bqflg=2 qflg=4 nitrate, phosphate problem.
        11    bqflg=2 qflg=4 nitrate, phosphate,nitrite problem.
        12    bqflg=2 qflg=4 nitrate, phosphate problem.
        13    bqflg=2 qflg=3 nitrate, phosphate problem.
        15    bqflg=2 qflg=4 nitrate, phosphate problem.
        20    bqflg=2 qflg=4 salinity .05 too high - no reason
        21    bqflg=2 qflg=4 salinity .03 too high - no reason

239/01: 8     bqflg=2 qflg=2 nitrate, phosphate - checked and looks OK ldt
        10    bqflg=2 qflg=4 nitrate, phosphate problem.
        11    bqflg=2 qflg=4 nitrate, phosphate problem.
        12    bqflg=2 qflg=4 nitrate, phosphate problem.
        13    bqflg=2 qflg=3 nitrate, phosphate problem.
        14    bqflg=2 qflg=3 nitrate, phosphate problem.
        15    bqflg=2 qflg=3 nitrate, phosphate problem.
        23    bqflg=2 qflg=4 oxygen problem - no reason?

240/01: 10    bqflg=2 qflg=4 nitrate, phosphate problem.
        12    bqflg=2 qflg=4 nitrate, phosphate problem.
        17    bqflg=2 qflg=3 salinity 0.01 low - no reason
        27    bqflg=2 qflg=3 salinity 0.05 high - no reason

241/01: 1     bqflg=2 qflg=3 salinity problem- no reason
        7     bqflg=2 qflg=3 salinity problem- no reason
        8     bqflg=2 qflg=3 salinity problem- no reason
        10    bqflg=2 qflg=3 salinity problem- no reason
        11    bqflg=2 qflg=4 nitrite of .07 - tube problem
        12    bqflg=2 qflg=4 nitrate, phosphate problem.
        13    bqflg=2 qflg=4 nitrite - tube problem
        15    bqflg=2 qflg=4 nitrite - tube problem

242/01: 1-36  bqflg=2 qflg=3,4 all nitrites bad.
        1     bqflg=2 qflg=4 all. bottom sediment sample.
        2     bqflg=4 qflg=5 all. empty
        8-21  bqflg=2 qflg=3,4 nitrate, phosphate problem.
        14    bqflg=2 qflg=2 Leaker (log sheet). no action

243/01: 1     bqflg=2 qflg=3 nitrate, phosphate.
        1     bqflg=2 qflg=3 salinity might be .003 high
        2     bqflg=3 qflg=4 all. Leaker, not noted on log.
        3     bqflg=2 qflg=3 nitrate, phosphate problem.
        4     bqflg=2 qflg=3,4 nitrate, phosphate, nitrite problem.
        5     bqflg=2 qflg=3 salinity problem- no reason
        6     bqflg=2 qflg=3 nitrate, phosphate.
        8     bqflg=2 qflg=4 nitrate, phosphate problem.
        9     bqflg=2 qflg=4 nitrate, phosphate problem.
        10    bqflg=2 qflg=4 nitrate, phosphate problem.
        11    bqflg=2 qflg=4 nitrate, phosphate problem.
        12    bqflg=2 qflg=4 nitrate, phosphate problem.
        13    bqflg=2 qflg=4 nitrite of .03
        15    bqflg=2 qflg=4 nitrite of .03
        17    bqflg=2 qflg=2 oxygen - checked and is ok

244/03: 2     bqflg=3 qflg=4 all. Leaker, not noted on log sheet
        5     bqflg=2 qflg=3 salinity .003-.005 high - no reason
        8     bqflg=2 qflg=4 phosphate problem.
        9     bqflg=2 qflg=3 salinity .01 high - no reason
              bqflg=2 qflg=4 phosphate problem.
        10    bqflg=2 qflg=4 phosphate problem.
        13    bqflg=2 qflg=2 silicate seems low, but fits other stations
        14    bqflg=2 qflg=2 silicate seems low, but fits other stations
        18    bqflg=2 qflg=3 nitrate, phosphate problem.
        20    bqflg=2 qflg=2 stopcock leaking (log sheet). no action
        23    bqflg=2 qflg=2 nitrate checked against others and OK
        24    bqflg=2 qflg=4 phosphate problem
        29    bqflg=2 qflg=2 silica checked against others and OK
        30    bqflg=2 qflg=2 silica checked against others and OK

245/01: 1     bqflg=4 qflg=4 all. bottom sediment sample.
        2     bqflg=4 qflg=9 all. empty
        3     bqflg=2 qflg=3 oxygen looks it was drawn from bottle 4
        4     bqflg=2 qflg=2 vent open (log sheet). no action
        14    bqflg=2 qflg=2 bottom leak (log sheet). no action
        25    bqflg=2 qflg=2 silica checked vs.  other stations and OK
        26    bqflg=2 qflg=2 silica checked vs.  other stations and OK

246/02: 10    bqflg=3 qflg=4 all. Leaker, noted on log sheet.
        14    bqflg=2 qflg=2 bottom not seated (log sheet). no action
        33    bqflg=2 qflg=2 salinities at 33 and 34 might have been reversed
        34    bqflg=2 qflg=2

247/01: 9     bqflg=4 qflg=9 all. empty
        14    bqflg=2 qflg=2 bottom leak (log sheet). no action

248/01: 31    bqflg=2 qflg=2 vent open (log sheet). no action
        25    bqflg=2 qflg=2 ALL vs. theta - checked. no action. 
              CTD O2 looks good.

249/02:  1    bqflg=2 qflg=3 nitrate, silicate small inversion - no reason
        10    bqflg=2 qflg=2 salinity about .01 high - no reason
        20    bqflg=2 qflg=2 nitrate, phosphate checked and OK ldt

250/01: 14    bqflg=2 qflg=2 nitrate checked and OK ldt

251/01: 64    bqflg=4 qflg=5 all. empty, (6) record tag deleted
                  I suspect this is "bottle" 6
        68    bqflg=3 qflg=4 all. (2) Leaker, not noted on log sheet.
                  I suspect this is "bottle" 2

252/01: 1-36  pylon off by one (36 tripped at deepest point and 35 at
              shallowest) - sorted out. no further action. no flags.

253/01: 68    bqflg=3 qflg=4 all. (3) Leaker, not noted on log sheet.
                  I suspect this is "bottle" 3

254/02:

255/01: 63    bqflg=4 qflg=9 all. empty, record tag deleted (8)
              (so no indication in .sea file of this trip)
        68    bqflg=3 qflg=9 all. Leaker, not noted on log sheet.
        67    bqflg=3 qflg=9 all. (4) Leaker, not noted on log.

256/01: 1-36  bqflg=2 qflg=3 all nitrates 0.5-1.0 too high
        5     bqflg=2 qflg=2 phosphate looks a little high, but no
                             action taken
        7     bqflg=2 qflg=4 salinity .01 too high - no reason
        8     bqflg=2 qflg=2 silica checked and OK
        31    bqflg=2 qflg=2 opened on deck. no action.

257/01: 51    bqflg=4 qflg=9 all. empty
                  I assume that 51 is "bottle" 11

258/01: 1-36  bqflg=2 qflg=3 nitrates 0.5-1.0 high.

259/01:

260/01:  2    bqflg=2 qflg=2 leak (log sheet). no action.
              This was the actual bottle which
              leaked, and it was located in the position 14;
              since WHOI software did not permit actual bottle
              numbers to be entered, the leaker is at location 14
              in the .sea file
        14    bqflg=3 qflg=4 all. Leaker, not noted on log sheet.
        20    bqflg=2 qflg=3 oxygen .3 ml/l high.  no reason.

261/01: 51    bqflg=4 qflg=9 all. empty, record tag deleted (11)
        62    bqflg=3 qflg=9 all. (9) Leaker, not noted on log.
                  I assume this is "bottle" 9.
        63    bqflg=4 qflg=9 all. empty, record tag deleted (8)
        ??    bqflg=2 qflg=9 I don't understand this one. There
              are no reported values for S or nuts but O2 is OK.

262/01:  4    bqflg=2 qflg=3 salinity .01 high - no reason
        19    bqflg=2 qflg=4 oxygen may be .05-.1ml/l high - no reason
        20    bqflg=2 qflg=3 salinity .01-.02 high - no reason
        35    bqflg=2 qflg=2 vent open.  No action.

263/01: 67    bqflg=4 qflg=9 all. empty (4)
                  I assume this is "bottle" 4
        68    bqflg=3 qflg=4 all. (3) Leaker, not noted on log.
                  I assume this is "bottle" 3
        69    bqflg=3 qflg=3: salinity flag
                  I assume this is "bottle" 2

264/01: 23    bqflg=2 qflg=3 salinity .05 low - no reason
        24    bqflg=2 qflg=3 salinity .05 low - no reason

265/01: 68    bqflg=3 qflg=4 all. (3) Leaker, not noted on log.
        69    bqflg=3 qflg=4 all. (2) Leaker, not noted on log.
                  I don't know which is 68 or 69.

266/01:  3    bqflg=4 qflg=9 all. empty.

267/01: 51    bqflg=4 qflg=5 all. empty, record tag deleted (11)
        68    bqflg=4 qflg=5 all. empty, record tag deleted (3) ONLY 8 TAGS

268/01: 31    bqflg=2 qflg=2 salinity thought .1 low but OK against CTD

269/01:  5    bqflg=3 qflg=9 all. Leaker, not noted on log sheet.

270/01:  2    bqflg=2 qflg=2 Leaker (log sheet). No action
        25    bqflg=2 qflg=2 valve open (log sheet).  No action.

271/01:

272/01: 11    bqflg=2 qflg=9 nutrients drawn from 10
        13    bqflg=4 qflg=9 all. empty
        35    bqflg=4 qflg=9 all. empty

273/01: all   bottle mixup sorted out
        65    bqflg=2 qflg=4 oxygen .8 ml/l high - no reason
                  I assume this is "bottle" 4
        68    bqflg=3 qflg=9 all. (3) Leaker, not noted on log.
         2    others  one other empty bottle, one other leaker

274/01: 1-36  bottle mixup - sorted out

275/01: 61    bqflg=2 qflg=2 vent open (log sheet) (10). no action.
        68    bqflg=2 qflg=2 vent open (log sheet) (3) no action.

276/01:  7    bqflg=2 qflg=3 salinity .01 low - no reason
        10    bqflg=2 qflg=4 oxygen problem - no reason

277/01: 62    bqflg=2 qflg=2 not closed tight (log sheet). (9) no action.

278/01: 1-36  bottle mixup, sorted out. no action.

279/01: 63    bqflg=3 qflg=9 all. (8) Leaker, not noted on log.
                  I assume this is "bottle" 8

280/01: 1-24  bqflg=2 qflg=2 bottle mixup, sorted out. no action.
         2    bqflg=2 qflg=2 bottle 2 replaced by 41 here.  no action.

281/01:

282/01:

283/01: all   bottle mixup - sorted out. no further action
        62    bqflg=2 qflg=2 hung up (log sheet) (9). no action.
        65    bqflg=2 qflg=4 salinity .15 high - no reason (6)
        67    bqflg=2 qflg=2 hung up (log sheet) (4). no action.

284/01: 14    bqflg=4 qflg=9 all. empty
        18    bqflg=2 qflg=4 salinity .01 high - no reason
        35    bqflg=2 qflg=2 vent open (log sheet). no action.

285/01: 63    bqflg=4 qflg=9 all. empty (8)
        67    bqflg=4 qflg=9 all. empty (4)

286/01: 25-36 rosette off by one.  sorted out.
         2    bqflg=2 qflg=2 salinity .01 high - no reason
        30    bqflg=2 qflg=4 oxygen 2 ml/l high - no reason

287/02: 25-36 bqflg=4 qflg=9 all. inner rosette not closed, empty
         3    bqflg=2 qflg=3 salinity - no reason
         1    bqflg=2 qflg=3 salinity - no reason

288/02: CTD touched bottom
         1    bqflg=2 qflg=2 oxygen slightly high re CTD
                               but may be fine

289/01:  1    bqflg=2 qflg=2 salinity slightly too high re CTD
         2    bqflg=2 qflg=3 salinity 0.005 too high re CTD
         3    bqflg=2 qflg=3 salinity 0.002 high - no reason
        30    bqflg=2 qflg=3 oxygen - possible dupe draw
        36    bqflg=4 qflg=9 all. empty

              Bottle 19 vs. bottle 29.  In the nutrients file there
              are two bottles identified as 29.  The first one
              corresponds to sequential number 19, thus we assume
              this was indeed bottle 19 and not 29. The second bottle
              29 has a sequence Nr.  of 29.  Nutrient data for the first
              bottle 29 (actually 19) look ok for the corresponding depth.

290/01:  1    bqflg=2 qflg=2 oxygen slightly high re CTD
         1    bqflg=2 qflg=3 salinity 0.005 high - no reason
         3    bqflg=2 qflg=3 salinity 0.006 high - no reason
        21    bqflg=2 qflg=2 oxygen checked against CTD and OK
        31    bqflg=2 qflg=2 bottom cap leak (log sheet)  no action

291/01:

292/01: 1-36  inner rosette fired first (25 to 36, then 1 to 24)
        8     bqflg=3 qflg=4 all. Leaker, not noted on log.
              Bottle numbers are correct in the .sea file.
              Actual bottle 32 was the leaker, but in position 8.

293/01: 33    bqflg=4 qflg=9 all. empty

294/01:  3    bqflg=2 qflg=3 salinity .002 high - no reason
        27    bqflg=2 qflg=2 Leaker (log sheet).  no action.

295/01:  8    bqflg=2 qflg=3 salinity .005 high - no reason
                  (CTD conductivity cell changed at this station)

296/01:  1    bqflg=2 qflg=4 oxygen may be .05 high - no reason
                             salinity .002 high - no reason
         5    bqflg=2 qflg=3 salinity .002 high - no reason
         6    bqflg=2 qflg=3 salinity .002 high - no reason
        11    bqflg=2 qflg=3 salinity .003 high - no reason

297/01:

298/01:  1    bqflg=2 qflg=3 salinity 0.002 high - no reason
         4    bqflg=2 qflg=3 nitrate problem - no reason
        11    bqflg=2 qflg=4 salinity 0.005 high - no reason
        12    bqflg=2 qflg=4 nitrate problem - no reason
        13    bqflg=2 qflg=4 salinity 0.01 low - looks like out of 14
        16    bqflg=2 qflg=4 oxygen 1.0 ml/l high - no reason
        19    bqflg=2 qflg=2 oxygen looks funny but agrees with
290-299

299/01:

300/03:  1    bqflg=2 qflg=4 salinity 0.007 high - no reason
                             bottom cap not seated well
              bqflg=2 qflg=3 nitrate 0.7umol high - no reason
         2    bqflg=2 qflg=3 nitrate 0.7umol high - no reason
        12    bqflg=2 qflg=2 plastic tiedown caught in bottom cap (log sheet)
        21    bqflg=2 qflg=3 salinity 0.014 high - no reason
        27    bqflg=2 qflg=2 Leaker (log sheet). no action.
        31    bqflg=2 qflg=2 Leaker (log sheet). no action.

301/01: 12    bqflg=3 qflg=4 all. Leaker, noted on log sheet.

302/01: 31    bqflg=4 qflg=9 all. empty
        32    bqflg=2 qflg=4 phosphate .6 low - looks like value from 33

303/01:

304/01:  1    bqflg=2 qflg=2 oxygen might be .1 high, but reasonable
         2    bqflg=2 qflg=2 oxygen might be .1 high, but reasonable
         4    bqflg=2 qflg=2 Leaker (log sheet). no action.
        28    bqflg=4 qflg=9 misfire  (log sheet). no action.

305/01:

306/01:

307/01: 1     bqflg=2 qflg=2 oxygen might be .1 high, but reasonable
        10    bqflg=2 qflg=2 silicate looks 2. high  but reasonable.

308/01: 1     bqflg=2 qflg=2 oxygen might be .1 high, but reasonable
        27    bqflg=2 qflg=2 Leaker (log sheet). no action.
        36    bqflg=2 qflg=4 salinity 10.0 psu high (possibly a typo)

309/01: 32    bqflg=3  rosette struck ship, knocked valve off 32.
                  salinity value OK.  no O2 or nuts.
                  watch for problems on bottles 25-36 - none found.

310/1: 1      bqflg=2 qflg=2 oxygen might be a little high but reasonable

311/1: 21     bqflg=2 qflg=3 silicate 5 low. Don't know why other nuts flagged.

312/1:

313/1: 29     bqflg=2 qflg=4 salinity dupe draw of 28
       26     bqflg=2 qflg=3 salinity may be dupe draw of 25

314/2:

315/1: 10     bqflg=2 qflg=3 nitrate may be .2 high
       29     bqflg=2 qflg=2 vent open (log sheet). no action.

316/1: 10     bqflg=2 qflg=3 salinity .01 high - no reason

317/2: 1-36   rosettes fired out of order. sorted out.
       1      bqflg=2 qflg=3 oxygen .1 high - no reason

318/1: 1      bqflg=2 qflg=2 Leaker (log sheet). no action.

319/1: 12     bqflg=2 qflg=2 silicate may be 2 high - no reason
       12     bqflg=2 qflg=3 salinity .002 high - no reason

320/1: 1      bqflg=2 qflg=2 oxygen looked high but fits 310-319
       11     bqflg=2 qflg=3 salinity may be .002 low - no reason

321/1: 1      bqflg=2 qflg=2 oxygen looked high but fits 310-320

322/1: 4      bqflg=2 qflg=3 oxygen might be .1 high - no reason

323/1: 13     bqflg=2 qflg=9 no oxygen value

324/1:

325/1:

326/1:


                              FIGURES

Figure A.2.1. Cruise track for WOCE P16C (31wttunes3), R/V T.
              Washington, 31 Aug 1991 - 1 Oct 1991. (a) Rosette/CTD
              station (circle).  Large volume plus large
              rosette/CTD station (+). (b) Equatorial stations.
              Regular rosette stations with CTD10 (circles).  LADCP
              rosette stations with CTD9 (+).

Figure A.2.2. JGOFS bio-optical stations on P16C.

Figure A.2.3. Small volume (10 liter) water samples on P16C.

Figure A.2.4. Large volume (Gerard) water samples on P16C.

Figure A.2.5. ALACE float (circles) and surface drifter (+)
              deployments on P16C.

Figure A.2.6. (a) Salinity, (b) oxygen, (c) silica, and (d) nitrate
              all vs. potential temperature, from P16S stations
              216-220 (solid, R/V T. Washington, 8/91, 31wttunes2)
              and from P16C stations 221-225 (x's, R/V T.
              Washington, 9/91), near 18S.

Figure A.2.7. (a) Salinity, (b) oxygen, (c) silica, and (d)
              nitrate, all vs. potential temperature, from TEW
              stations 2-4 (solid) and P16C stations 228-232
              (triangles), at 12S.  The TEW stations were collected
              in June, 1987.

Figure A.2.8. (a) Salinity, (b) oxygen, (c) silica, and (d)
              nitrate, all vs. potential temperature, from Moana
              Wave stations 128-131 (solid) and P16C stations 298-
              302 (triangles), at 10N. The Moana Wave stations were
              collected in April, 1989.

Figure A.2.9. Phosphate vs. potential temperature, from (a) P16S
              stations 217-220 and P16C stations 221-224 near 18S,
              (b) TEW stations 2-4 and P16C stations 228-232 at
              12S, (c) Moana Wave stations 128-131 and P16C
              stations 298-302 at 10N.

Figure C.1.1. Pre-cruise and post cruise quadratic fits to CTD #9
              and CTD #10 laboratory temperature calibration data

Figure C.1.2. Pre-cruise and post cruise quadratic fits to CTD #9
              and CTD #10 laboratory pressure calibration data

Figure C.1.3. Pre-cruise and post cruise quadratic fits to CTD #9
              and CTD #10 laboratory conductivity calibration data

Figure C.1.4a.CTD#10 conductivity sensors A and B.  Pre-cruise
              nominally calibrated CTD conductivity data
              differenced from rosette water sample data.

Figure C.1.4b.CTD#9 conductivity sensors A and B.  Pre-cruise
              nominally calibrated CTD conductivity data
              differenced from rosette water sample data.

Figure C.1.5. Salinity differences (rosette - CTD) of final
              calibrated CTD data. Full profile (bottom); Below
              2000 db (top).

Figure C.1.6. Oxygen differences (rosette - CTD) of final
              calibrated CTD data. Full profile (bottom); Below
              2000 db (top).

Figure C.1.7. Final calibrated CTD salinity and oxygen data.
              Rosette minus CTD differences vs. pressure.

Figure C.1.8. Histogram plot of differences between final
              calibrated CTD and rosette water sample data.

Figure C.1.9. Salinity on potential temperature surfaces 1.1 to
              2.0C, separated by 0.1C.  The smoother overlying
              curve is CTD#10 only.  The jagged curve includes both
              CTD#9 and 10.

Figure C.1.10.Average salinity vs. potential temperature for each
              isotherm 1.1 to 2.0C, separated by 0.1C.  Error bars
              are one standard deviation. (a) CTD#9. (b) CTD#10.
              (c) The averages of both CTD#9 and 10 replotted from
              a and b.

Figure C.5.1. Combined time series measurements of orthphosphate
              (uM/l) using different washing methods for pre-
              cleaning the sampling tubes used during P16C to draw
              samples from the Niskin and Gerard bottles.  The
              washing methods were: (a) seawater, (b) distilled
              water, (c) 80% isopropyl alcohol, and (d) 1.2 M HCl.
              The vertical lines on each sample represent the
              standard deviation of the mean (N=3).  The horizontal
              broken line represents the root mean square deviation
              of all replicate samples for PO3- 4 collected during
              P16C and analyze within 2-3 hours after collection.
              This is an estimate of our short-term precision.  The
              solid line represents +-1% of highest water PO3- 4
              column values.  This is a target precision level for
              WOCE hydrographic measurements for dissolved
              inorganic nutrients.

Figure C.5.2. Same as Fig. C.5.1 but for NO3 (umo/l).

Figure C.5.3. Same as Fig. C.5.1 but for NO2 (umo/l).

Figure C.5.4. Same as Fig. C.5.1 but for silicic acid (umo/l).






G.   DATA QUALITY EVAULATION


G.1  DATA QUALITY EVALUATION of TUNES LEG III (P16C) HYDROGRAPHIC DATA
     (A. Mantyla)
     28 June 1994

The data originators have done a very through job in evaluating and
resolving the numerous data problems encountered on this cruise:  I
have made very few changes to their quality flags.  I tended to be a
little more accepting to a slight nutrient bumps and a little more
critical on salinity errors.

In the cruise report, the PI's  document differences between TUNES Leg
II and III, as well as differences from other expeditions that crossed
the TUNES III track.  They point out the analytical problems
encountered on the cruise and the surprising differences between the 2
TUNES legs where the cruises overlapped.  There were unexpected
problems in all analyses, considering the experience of the analytical
groups on the cruise.  For nutrient problems to persist for the first
quarter of the cruise simply due to dirty sample tubes is astonishing!
The salinity problems seen early in the cruise may not have been
entirely analytical:  the sample collection is also suspect.  The CTD
processing section of the cruise report noted that some salinity
samples were not tightly sealed, which results in artificially higher
results.  There are also several stations, some listed below, where
samples were evidently collected out of sequence.  Deep oxygens showed
unlikely station to station shifts.  Some have been flagged
questionable (usually higher), but at some point it became difficult to
tell which were the unlikely ones,  the higher one or the low one.

Many water samples are plainly not from discrete depths, but are
"smeared" over some depth range, as revealed by large differences
between the CTD and water sample salinity seen on many stations,
particularly in depths of strong salinity gradients.  The differences
are usually in the direction of deeper salinity, indicating that the
rosette bottles were either tripped on the fly, or too quickly to allow
sufficient flushing of the rosette bottle at the target depth.  The
water samples are usable, but the essential salinity verification of
correct trip and no leakage is lost in those cases.  I would urge that
the console operators slow down at the bottle stops and allow a little
more time for the rosette bottle to collect a good sample at the
desired depth before tripping the bottle.  At present, wire casts do a
better job of collecting discrete water samples, but there isn't any
reason why rosettes can't do almost as well, given a little thought and care.

I'm not familiar with how CTD data is assigned to the bottle trips on
this cruise, but it showed be the CTD data recorded for a few seconds
before the bottle is tripped so as to be equivalent to the rosette
bottle history just before the bottle closure.  Station 221 had 5 trips
at the same depth as indicated by the identical CTD P, T, and S data
tabulated for the 5 trips, obviously not the actual CTD data at the time
of each sequential trip.  Since the CTD data were not taken at the time
of each bottle trip, that may be part of the reason why CTD versus
bottle comparisons are not as tight as seen on other cruises.

The following are  some specific problems that may be able to be
resolved by the PI's:

223 #1 and 2: Odd pressure reversal in final pressures are not in raw 
          pressures. From raw minus final pressure differences above, looks 
          like # 1 should be at 4130 db instead of 4117 db. Suggest data 
          originator make correction.

228 #'s 7,8, and 9: I've flagged these 3 salinity questionable, but they would 
          be OK if one assumed that they were actually collected from one depth 
          deeper; the CTD salinity and adjacent station Theta-Salinity curves 
          would support that assumption. Also, salinity samples 22 and 23 
          appear to have been reversed compared to the CTD salinity, but the 
          errors are small for this depth, so I did not flag them.

232 #'s 7,8,and 9: Flagged all salts questionable, thought would be ok if moved 
          down one depth. Most likely a sample collection error.

249 #'s 7,8,9,10: Flagged all 4 salts uncertain, would be ok if from a depth or 
          two deeper. O2's confirm not a rosette mis-trip, so most likely a 
          sampling error.

308#36:   Bottle salt 44.2580 must be a key entry error:34.--- would be ok. 
          Suggest originator verify and correct, if so.

311#21:   All water samples flagged as questionable. The profiles suggest that 
          the data is from 50 to 100db shallower. Is there any way to verify 
          the trip depth? It would be nice if this were just a typo and the 
          data could be assigned to a more probably depth, and confirmed by the 
          CTD salinity and oxygen. 



G.2  CTD DATA QUALITY EVALUATION
     (Neil White)

1. All temperatures are in t68.  While WHOI may have made a decision to
   stick with t68 I had understood (e.g. from a memo from Peter Saunders,
   the chairman of the WHP subgroup on standards and calibration)  that
   t90 should be adopted as soon as possible.  Surely this data should
   have been converted to t90 before it was submitted to the WHP office?

2. All CTD station headers (in the stannn.wct files) have the 9th of
   September, 1991 as their date.
   
3. Many oxygen values which have been flagged as bad have silly values
   (e.g. -393.1) instead of -9.  In addition where data has been flagged
   as bad the number ber of observations has been set to -9, even though there
   is still usable data in some channels.
   
4. Station 251 has 2 decibar averages centred on even integers.  This
   is apparently due to the use of pressure-sorted upcast data in the
   absence of usable downcast data, but it is still a big alarming that
   no-one seems to know how this happened, or to care!
   
5. The documentation use ml/l for dissolved oxygen values.  This is
   confusing when everything else is in molar units..
   
While a number of these poinsts are minor it all adds up to a data set
whose presentation does not inspire confidence.

Another aspect of this data set which I found alarming was the extent to
which the originators were prepared to interpolate over gasps in the
data sometimes even interpolating between 'fudged' (their terminology)
data points.  If interpolated data is to be provided then it must,
surely, be considered 'fit for purpose' in some sense.  I find it very
hard to think of any purpose for which same of the interpolated data
provided would be fit.  Station 225 is the most extreme example, with
interpolation over substational depth ranges (100m) near the surface,
completely ignoring the structure in this part of the water column.
This is exacerbated by the fact that some of the values at the end
points (flagged as 'good' data) are clearly wrong.  

WOCE AND NON-WOCE STATIONS
Stations are numbered from 221 to 326.  Odd-numbered stations from 251
through 285 were not WOCE stations.  I will restrict most of my
comments to the WOCE stations.

TEMPERATURE CALIBRATION 
The temperature calibration procedure at WHOI is described, and a
statement to the effect that the calibration is believed to be good to
.002 C is made.  Surely an error budget has been done for the calibration
lab, in which case some confidence limits on the calibrations should be
given.

SALINITY AND DISSOLVED OXYGEN CALIBRATION
On the whole the data processors seem to have done a good job of
calibration of the CTD salinity and dissolved oxygen channels.  Lynne
Talley has looked at deep Theta/salinity data.  I have not repeated
that analysis, but will look mainly at the actual goodness of fit
between CTD and bottle data as requested.  Inevitable some of the
stations Lynne has hightlighted also get a mention here.

The willingness of the processors to take algorithms which are based on
the physical properties of sensors and make them 'unphysical' worries
me a bit.  One example of this is the practice of changing the
conductivity cell deformation coefficient to say that either it doesn't
shrink with pressure, or that it expands with pressure.  Another example
is the negative lags accepted for the oxygen sensor for stations
238-240.  While I can think of no better ideas and am award of many of
the vagaries of oxygen sensors I find it worrying that what started as
an attempt to model the behaviors of a sensor seems to have turned into
an exercise purely in many-parameter fitting.  

For salinity (figure 1) and oxygen (figure 2) 1 have plotted profiles of 
scaled offsets between bottles and downcast CTD ValLies. Deep offsets are 
plotted at a larger scale than shallow ones - the scale is shown by the two 
lines on the left hand side of each frame. At any depth the width of the 
wedge represents an offset (bottle - CTD) of .01 psu (figure 1) or 4 micro-
moles (figure 2). Non-WOCE stations are Indicated by Stations numbers in 
brackets.

Shallow (0 - 1000m) fits

The cruise report mentions sampling problems early in the cruise. Some of 
these seem to show up in the shallower samples. See figures 1 and 2 and 
figures 3a,b,c,...,1 (plots of the stations mentioned).

While there is (understandably) an emphasis on minimizing the residuals
in deep water I feel that , perhaps, a bit more attention should be
paid to the quality of fit in shallower water.  While we can't expect
the fit in shallower water to be as good because of a variety of
phenomena (oceaographic variability, internal waves, hight gradients,
vertical distance between CTD sensors and sample bottle, long oxygen
sensor time constant, etc) I feel that may of the problems mentioned
below should have been picked up by the data processors.  In places
there are quite substantial misfits in both salinity and oxygen which
are not explainable in terms of any of the above-mentioned phenomena,
especially as, for some of them, the downcast and upcast CTD values
agree quite closely, but the bottle values are substantially offset.

Note that only samples flagged as good data (quality byte=2) are
considered here.

STATION 224: The salinity from about 200-400 metres are a very poor 
             fit (out by up to .33 psu), and seem to e out by enough to 
             wonder whether the bottle depths are incorrect.

STATION 225: Similar to 224 but the differences aren't as large. It 
             is a pity that there is no oxygen profile data for these 
             STATIONs as this might give some corroborating information 
             on whether the bottle depths are correct or not.
   
STATION 229: More problems in the thermocline, this time smaller 
             differences, but in the opposite sense. The comments for 
             the above-mentioned STATIONs apply here also. The oxygen 
             profile doesn't really help to resolve the issue here.
   
STATION 230: More of the same, and the fact that the oxygen samples 
             are also offset suggests a sampling/bottle identification 
             problem.

STATION 234: The samples at 260, 309 and 360 metres all look as if 
             they have been misplaced or incorrectly sampled. Both 
             salinity and oxygen samples are offset at all three 
             depths.
   
STATION 237: The samples at 209 and 260 metres are both offset. Both 
             salinity and oxygen are offset at 260 metres.
   
STATION 241: Salinity samples at 109 and 210 metres both look 
             suspicious.
   
STATION 243: Again, very poor salinity fits at 234, 258 and 284 
             metres, with fairly poor oxygen fits at 258 and 284.
   
STATION 245: Again, poor fits in both salinity and oxygen at 205, 
             229 and 254 metres.
   
STATION 262: While the fit is generally better that for some of 
             these STATIONs, the CTD salinity profile seems to be 
             consistently below the bottles in the 400-600 metres range 
             and also at some other samples. In fact, the mean offset 
             of the 17 samples from 0-1000 metres is .018 psu - surely 
             too high.
   
STATION 289: The oxygen sample at 252 metres is surely wrong.

STATION 313: There is a more-or-less consistent salinity offset from 
             69 to 365 metres. The mean offset of the 17 salinity 
             samples from 0 - 1000 metres is .028psu.

DEEP SALINITY FITS:

Overlaying theta/CTD salinity and theta/bottle salinity plots of
stations 240-245 and 246-250.  It shows that the CTD salinity for
stations 240-245 are noticeably higher compared to the bottle
salinity.  One could also argue that the CTD salinity for stations
246-250 are a little low compared to the bottles.  The mean offsets
between 1000 and 5000 metres are:


                 Station     Mean offset
                 ---------------------------
                 240         -.003
                 241          .001
                 242         -.002
                 243          .000
                 244         -.001
                 245         -.002
                 246          .002
                 247          .000
                 248          .000
                 249          .001
                 250          .000
                 

I feel that this part of the cruise should be looked at again.  The
jump of .004 psu between stations 245 and 246 is presumably a function
of the fact that this is a boundary between groups.  It is a large jump
in the context of the WOCE aims for accuracy.

Stations 253 and 263 should also be looked at again if WOCE accuracy is
being southt for these (non-WOCE) stations.

Other stations where there seems to be a mean deep-water offset between
the CTD profile and the bottles worth looking into are:

                 Stations     Mean offset (1000-5000m)
                 -------------------------------------
                 223           .003
                 224           .002
                 231          -.002
                 235          -.002
                 236          -.002
                 271           .002
                 276          -.002
                 282          -.002
                 284          -.002
                 288          -.002
                 291          -.002
                 305          -.002
                 319          -.002

None of these stations are at group boundaries and some of these
offsets could well be due to the sampling problems early in the cruise.
They could also be due to the tendency of the CTD calibration process
to smooth out the variability in the bottle data.  However, I suggest
that these stations be looked at again.

DEEP OXYGEN FITS
The processors seem to have done a good job of calibrating the deep
oxygen profiles.  The only station which sticks out as one needing to be
looked at again is station 319 with a mean offset of 2.0 micromoles
(CTD higher than bottle) between 1000 and 5000 metres.



G.3    LARGE VOLUME DATA QUALITY EVALUATION
       (Robert M. Key) 
       November 14, 1994

G.3.a  GENERAL INFORMATION

WOCE section P16C was the third in a series of three cruise legs which have 
been collectively referred to as "TUNES". Most of the general information 
pertinent to this cruise have been reported by Lynne Talley who was chief 
scientist for this leg. This adden-dum to her report covers details of data 
collection and analysis for the large volume Ger-ard samples.

A total of 8 large volume (LV) stations was occupied on this leg. The cruise 
plan called for 2 Gerard casts of 9 barrels each at each LV station. The 
planned sampling densi-ty was 1 station every 5 of latitude (~300nmi). Each 
Gerard barrel was equipped with a piggyback 5 liter Niskin bottle which, in 
turn, had a full set of high precision reversing thermometers to determine 
sampling pressure as well as temperature. In the event of mis-tripped Gerard 
sampler(s), casts were repeated as time allowed in an attempt to collect the 
full suite of samples.

All LV casts for the TUNES cruises were done using the stern A-frame on the 
R/V Thomas Washington. As is generally the case, the combination of a small 
vessel with working off the stern led to an elevated failure rate for the LV 
work relative to working off the side of a larger vessel. This problem is a 
function of the accelerations on the trawl wire caused by ship motion and sea 
state. These problems were minimized by the exceptional effort and capability 
of the Washington's crew.

At the first station on this leg (225) both Gerard and Niskin were sampled for
salin-ity and silicate. At the remainder of the stations salinity and the full
complement of nutri-ents (silicate, phosphate, nitrite and nitrate) were run 
on each sample pair. These nutrient and salinity results have been used to 
help assure that the Gerard barrels tripped at the de-sired depth and to 
ascertain whether or not the Gerard barrel leaked during retrieval. For this 
leg, D14C was the only LV tracer measurement made on the Gerard samples. 
Table 1 summarizes the LV sampling.


TABLE 7. LV Sampling Summary
 
              Station  Cast  Latitude   Longitude    No.
                                                     Ger. Samples
              -------  ----  ---------  -----------  ------------
                225     1    15 31.4 S  150 39.4 W   5
                        3                            5
                        4                            3
                235     1    10 30.5 S  150 58.5 W   8
                        3                            4
                        4                            5
                244     2      6 0.0 S   151 0.0 W   9
                        4                            9
                259     2     1 30.0 S   151 0.0 W   9
                        3                            9
                288     1      4 0.0 N   151 0.0 W   9
                        3                            9
                300     2     9 54.5    151 57.0 W   9
                        4                            9
                308     1    13 51.5 N  152 41.5 W   9
                        4                            9
                317     1     18 0.0 N  153 30.0 W   9
                        4                            9
              Total    17                          138


G.3.b  PERSONNEL

LV sampling for this cruise was under the direction of Paul Quay 
(U. Washington). Quay and Robert Key (Princeton U.) are the principal 
investigators for this work. All LV 14C extractions at sea were done by either
Quay or Leonard Lopez (SIO-ODF). In addition to Quay and Lopez, deck work was 
done by the WHOI CTD group with assistance from many of the scientific party. 
Lopez was primarily responsible for reading thermometers. Salinities and 
nutrients were analyzed by the WHOI CTD group and the Oregon State Univ. 
group respectively. 14C analyses were performed at Minze Stuiver's 
(Sta 225-259) and Gte stlund's (Sta 288-317) laboratories. Key collected 
the data from the origina-tors, merged the files, assigned quality control 
flags to all the data and submitted the data files to the WOCE office 
(10/19/94). 

G.3.c  RESULTS

Prior to this, a preliminary subset of this data was submitted to the WOCE 
office. This data set and any changes or additions supersedes any prior 
submission.

In this data set Gerard samples can be differentiated from Niskin samples by 
the bottle number. Niskin bottle numbers are in the range 41-71 while Gerards 
are in the range 81-94.

G.3.d  PRESSURE AND TEMPERATURE

Pressure and temperature for the LV casts are determined by reversing thermome-
ters mounted on the Niskin bottle. Each bottle was equipped with the standard 
set of 2 pro-tected and 1 unprotected thermometer. All thermometers, 
calibrations and calculations were provided by SIO-ODF. Reported temperatures 
for samples in the thermocline are be-lieved to be accurate to 0.01C and for 
deep samples 0.005C. Pressures were calculated using standard techniques 
combining wire out with unprotected thermometer data. In cas-es where the 
thermometers failed, pressures were estimated by thermometer data from 
adjacent bottles combined with wire out data. Because of the inherent error 
in pressure calculations and the finite flushing time required for the Gerard 
barrels, the assigned pressures have an uncertainty of approximately 10 dB. 
The pressures recorded in the data set for each Gerard-Niskin pair generally 
differ by approximately 0.5 dB with the Gerard pressure being the greater. 
This is because the Niskin is hung near the upper end of the Gerard. 
Maintaining this difference has a advantage for some computer software 
(particularly gridding and interpolation programs) which do not handle 
multiple data at exactly the same location.

G.3.e.  SALINITY

Salinity samples were collected from each Gerard barrel and each piggyback Ni-
skin bottle. Analyses were performed by the same personnel who ran the salt 
samples collected from the Rosette bottles so the analytical precision should 
be the same for LV salts and Rosette salt samples. When both Gerard and Niskin
trip properly, the difference between the two salt measurements should be 
within the range 0.000 - 0.003 on the PSU scale. Somewhat larger differences 
can occur if the sea state is very calm and the cast is not "yoyo'ed" once 
the terminal wire out is reached. This difference is due to the flushing 
time required for the Gerard barrels and the degree of difference is a 
function of the salinity gradient where the sample was collected. In addition 
to providing primary hydrographic data for the LV casts, measured salinity 
values are used to calculate potential density values for these samples and 
to help confirm that the barrels closed at the desired depth. For the area 
covered by this leg, deep nutrient values (especially silicate) are more 
useful for trip confirmation than salt measurements due to the very low salt 
gradients.

G.3.f  NUTRIENTS

Nutrient samples were collected from Gerard and Niskin samples. On the first 
station, only silicate values were reported. LV nutrients were measured along 
with Rosette nutrients so the precision for these analyses should be the same.
For some unknown reason, nutrients collected from LV casts are frequently 
subject to systematic offsets from samples taken from Rosette bottles. For 
this reason it is recommended that these data be viewed only as a means of 
checking sample integrity (i.e. trip confirmation). The Rosette-Gerard 
discrepancy is generally less for silicate than for other nutrients. 

The raw nutrient data files provided by OSU were in units of mmol/liter. 
Conversion to mmol/kg was done using the measured sample salinity and a 
laboratory temperature of 25.5C (Joe Jennings, personnel communication).

G.3.g.  14C

The D14C values reported here have been distributed (but not "released" by the 
WOCE definition) in various data reports produced by stlund. stlund's 
reports included preliminary hydrographic data and are superceded by this 
submission.

All Gerard samples deemed to be "OK" on initial inspection at sea were 
extracted for 14C analysis using the technique described by Key (1991). The 
extracted 14CO2/NaOH samples were returned to the Ocean Tracer Lab at 
Princeton and subsequently shipped to stlund's lab. stlund divided the 
sample set and shipped the samples for stations 225-259 to Stuiver. These two 
laboratories have been cooperating on sample analysis for approximately 20 
years and are thoroughly intercalibrated. stlund's lab reports a preci-
sion of 4 for each measurement based on a long term average of counting 
statistics. Stuiver's lab reports individual errors for each measurement which 
range from 2-4. Quality control of the resulting measurements showed no 
statistically significant difference between results from the two labs. Of the
138 Gerard samples summarized in Table 1, 14C has been measured on 121 (88%). 
This exceeds the rate funded for this work (80%). Once the WOCE central 
Pacific data set is merged, some of the remaining samples may be analyzed if 
warranted.

Existing 14C data for the area sampled on this cruise is limited to the 
GEOSECS measurements. Comparison of these two data sets indicates that they 
are in agreement to the precision of the measurements.

G.3.h.  SUMMARY OF SAMPLE COLLECTION AND 14C EXTRACTION NOTES

The following list summarizes comments recorded on the sample collection, ther-
mometer, and 14C extraction log sheets. Any text in this listing shown in 
italics is a comment added after the fact to help the reader interpret the 
potential significance of the original comment. Comments from Talley's 
original LV report are repeated here.

STATION 225

    Cast 1. Five barrels tripped

            Gerard 89/Niskin - 45 N-G salt = -.005, data entry ok. 
            Silicate value also indicated that 45 may have closed 
            after cast started up.

    Cast 3. Five barrels tripped. Messenger hangup on bottle 89. 
            Bottom 4 barrels sent back down as cast 4

            Gerard 89 - low volume noted when sample transferred to 
            14C extraction drum.

    Cast 4. Three barrels tripped.

            Gerard 85/Niskin 71- did not trip. No messenger.

            Gerard 90/Niskin 47 Niskin did not trip. No water or temp. 
            Gerard looks ok.

            Gerard 93/Niskin 48 N-G salt = .004. Entry ok. Similar 
            difference in nutrients, but does not indicate consistent 
            leak in either. 

STATION 235

    Cast 1. Only 8 barrels hung. All tripped.

            Gerard 89 lid slightly ajar. A Gerard lid can close and 
            seal without latching.

            Gerard 90 pinch clamp cracked during extraction in drum 
            #8, may have leaked a little. Possible decrease in 
            extracted gas sample size, but generally not a significant 
            problem.

    Cast 3. Four barrels tripped. Messenger hangup on bbl 87. 
            Remaining 5 barrels sent back down as cast 4 (? 14C 
            extraction sheets record retry as cast 3; ODF records show 
            retry as cast 4. Cast listed as #4 in these records).

            Gerard 81 cork popped off for a few minutes near end of 
            14C extraction. Possible decrease in extracted gas sample 
            size, but generally not a significant problem.

            Gerard 84/Niskin 43 N-G salt = -.009. Nutrient data also 
            indicates that Niskin 43 is a "bad" sample. Gerard looks 
            ok.

            Gerard 87/Niskin 45 N-G salt = .004 otherwise both samples 
            look ok. Pinch clamp cracked on drum 13, leaked 1 minute 
            during 14C extraction. Possible decrease in extracted gas 
            sample size, but generally not a significant problem.

    Cast 4. Five barrels tripped.

            Gerard 85/Niskin 49 Intended pressure was 2756dB. Therms 
            and bottle data indicate trip depth of approximately 
            1812dB. Gerard data looks OK at this level and bottle flag 
            set to 3. Niskin data still looks bad. Sample log: "Looks 
            like barrel pretripped". Pinch clamp cracked on drum 17, 
            leaked 1 minute. Possible decrease in extracted gas sample 
            size, but generally not a significant problem.

            Gerard 90/Niskin 71 Intended pressure was 3053dB. Therms 
            and bottle data indicate trip depth of approximately 
            1987dB. No water samples from Niskin. Consider all data 
            highly suspect. 14C data does not fit at this level.

            Gerard - 93 leaks air on push(?) slight 0-ring damage. 14C 
            data looks OK.

STATION 244

    Cast 2. Niskin PO4 values higher than Gerard values by 0.2. 
            Gerard PO4 values look OK. Possible sample tube 
            contamination.

            Gerard 90/Niskin 71 Thermometers indicate Niskin tripped 
            at approximately 4327dB rather than intended 5150dB. Water 
            samples indicate that Gerard tripped at intended depth. 
            Niskin samples marked "bad".

    Cast 4. Gerard 90/Niskin 71 Thermometer and Niskin samples 
            indicate that Niskin tripped at approximately 1791dB. 
            Gerard values indicate that it tripped closer to intended 
            level of 2886dB, but salt, NO3, and PO4 are save as level 
            above (449/485 at 2632dB). Gerard silicate shows smooth 
            trend. 14C could be from shallower depth, but not as 
            shallow as Niskin. 14C flagged as questionable.

STATION 259

    Cast 2. Gerard 87/Niskin 43 N-G = -0.10. Nutrients also show very 
            slightly anamolous differences. 14C looks ok. 

    Cast 3. Messenger hangup on bbl 93. Remaining 3 barrels send 
            back down. Both lowereings recorded as Cast 3. Six barrels 
            tripped on first try, all three on second lowering.

            Gerard 93/Niskin 50 Thermometer rack did not reverse. 
            Pressure estimated from wire out and neighboring bottles. 
            N-G salt = -.012. Silicate on Niskin also questionable. 
            Niskin flagged as bad. Gerard looks OK

            Gerard 83 Tygon tubing going to 14C pre-stripper slipped 
            off (extractor board #2) after 4 hours of extraction and 
            was off for 20 minutes or less. Decrease in extracted gas 
            sample size, but probably not a significant problem this 
            stage of the procedure.

STATION 288

    Cast 1. Gerard 84/Niskin 45 G-N differences indicate possible 
            slight leak in Gerard. 14C not reported for this Gerard

    Cast 3. Gerard 85/Niskin 49 N-G salt = 0.010, silicate 1.1 
            difference. 14C looks OK.

            Gerard 90/Niskin 48 N-G salt = -0.012, silicate 0.7 
            difference. 14C looks to be high by about 10 marked as 
            questionable.

STATION 300

    Cast 2. Gerard 93/Niskin 71 N-G salt = -0.019. Nutrients also 
            indicate problem with Niskin. All water values from Niskin 
            marked as "bad". Gerard data looks OK including 14C.
  
    Cast 4. Gerard 85/Niskin 48 Gerard and therms look OK, no water in 
            Niskin.

            Gerard 90/Niskin 49 N-G = -0.010, silicate and 14C look 
            OK.

STATION 308

    Cast 1. Gerard 90/Niskin 49 Tube slipped off on #8 extractor after 
            14C extraction when transferring NaOH from extractor back 
            into sample bottle. Solution loss estimated at 25 ml. 
            Decrease in sample size, but not a significant problem.

            Gerard 93/Niskin 71 N-G salt = 0.007, no silicate 
            difference and some difference in NO3 and PO4. 14C looks 
            to be low by approximately 10. Gerard values flagged as 
            questionable.

STATION 317

    Cast 1. Gerard 84/Niskin 43 Both apparently mistripped at 
            approximately 815dB rather than the planned level of 
            3483dB. Data from both looks OK at this level. 14C not 
            reported for this sample.

            Gerard 87/Niskin 45 Sample log note implies mistrip with 
            this pair, but hydro data all looks OK. 

    Cast 4. Gerard 90/Niskin 71 Some serious confusion here. 
            Temperature data sheet shows this pair at the deepest 
            level while the Sample Log shows this pair to be next to 
            the deepest for this cast. Temp. data sheet has erasures 
            and note: "change out" between 448/485 and 449/493. 14C 
            not reported for this sample.

            Gerard 93/Niskin 49 See comments for 90/71 pair above. 14C 
            marked as question- able along with other data from Gerard. 



G.4  P16C TUNES-3 FINAL REPORT FOR AMS 14C SAMPLES
     (Robert M. Key & Paul Quay)
     July 6, 1996


1.0 GENERAL INFORMATION

WOCE section P16C was the third in a series of three cruise legs referred to 
as "TUNES". Lynne Talley of SIO was chief scientist for this leg. This report 
covers details of data collection and analysis for the small volume radio-
carbon samples. The reader is referred to "Documentation for WOCE Hydrographic 
Program section P16C" by Talley as the primary source for cruise information. 
Of 106 stations, 29 were sampled for radiocarbon. The AMS station locations 
are shown in Figure 1 and summarized in Table 1. 14C samples were additionally 
collected for measurement by the large volume technique on 8 stations (225, 
235, 244, 259, 288, 300, 308 and 317). AMS sampling was used for the upper 
thermocline and large volume sampling for the deep and bottom waters.


TABLE 1: P16C 14C Station Data

                      Date                       Bottom
              Station 1991  Latitude  Longitude  Depth (m)
              ------- ----  --------  ---------  ---------
                222    9/1   -16.994   -150.494    3770
                226    9/3   -14.999   -150.835    4528
                230    9/4   -12.993   -151.003    4595
                235    9/6   -10.508   -150.988    4910
                238    9/7    -9.000   -150.996    3840
                242    9/8    -7.018   -151.003    5182
                246    9/10   -5.013   -151.005    4985
                250    9/11   -3.007   -151.013    4765
                256    9/12   -1.998   -150.991    4749
                262    9/14   -1.007   -150.997    4720
                268    9/15   -0.005   -150.999    4340
                274    9/16    0.993   -150.998    3803
                280    9/17    1.996   -151.002    4409
                286    9/18    2.978   -151.003    5087
                290    9/20    4.996   -151.003    5060
                294    9/21    6.959   -151.348    5384
                298    9/22    8.943   -151.755    5056
                302    9/23   10.907   -152.112    5345
                306    9/25   12.865   -152.503    5561
                310    9/26   14.839   -152.891    5815
                314    9/28   16.802   -153.267    5185
                319    9/29   18.400   -154.474    5162



G.4.2    PERSONNEL

14C sampling for this cruise was under the direction of the PI, Paul Quay (U. 
Washington). 14C analyses were performed at the National Ocean Sciences AMS 
Facility (NOSAMS) at Woods Hole Oceanographic Institution, however, most of 
the sample extractions and accompanying 13 C measurements were made in Quay's 
lab. Salinities and nutrients were analyzed by the WHOI CTD group and the 
Oregon State Univ. group re-spectively. R. Key (Princeton) collected the data 
from the originators, merged the files, as-signed quality control flags to the 
14C and submitted the data files to the WOCE office (7/96).


G.4.3    RESULTS

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

G.4.3.1  HYDROGRAPHY

Hydrography from this leg have been submitted to the WOCE office by the chief 
scientist and described in the previously mentioned report.

G.4.3.2  14C

Most of the delta 14C values reported here have been distributed in a data 
report (NOSAMS, 1996). That report included preliminary hydrographic data and 
14C results, which had not been through the WOCE quality control procedures. 
This report supersedes that data distribution.

At this time 346 of 384 samples have been measured and reported. Replicate 
measurements were made on 6 of the water samples. These replicate analyses are 
tabulated in Table 2. The table shows the mean and standard deviation for each 
set of replicates. For these few samples, the average standard deviation is 
3.8o/oo. This precision estimate is somewhat smaller than the mean for the 
time frame over which these samples were measured. For a summary of the 
improvement in precision with time at NOSAMS, see Key, et al. (1996). In the 
final data reported to the WOCE office, the error weighted mean and error 
weighted standard deviation of the mean are given for replicate analyses.


TABLE 2: Summary of Replicate Analyses

                                                     Standard
           Sta-Cast-Bottle  delta 14C  Err  Mean(a)  Deviation(b)
           ---------------  ---------  ---  -------  ------------
              242-1-27       -87.5     2.7   -87.9       0.6  
                             -88.3     2.9
              290-1-32        65.6     2.7    65.8       0.2
                              65.9     2.7
              302-1-30       -28.7     2.7   -34.9       8.7
                             -41.0     2.9
              306-1-28      -117.1     3.6  -117.4       0.4 
                            -117.7     2.8
              310-1-29       -87.1     2.8   -93.3       8.7  
                             -99.4     3.9
              319-1-28(c)    -30.7     3.1   -33.6       4.2
                             -32.8     3.4
                             -29.8     3.2
                             -40.5     6.8
                             -34.3     4.1 
              (a) Error weighted mean reported with data set
              (b) Error weighted standard deviation of the mean
                  reported with data set.
              (c) 3 of 4 averaged for final data set


Because of the time and costs involved, direct comparisons were only 
infrequently made between the large volume and AMS methods for determining 
delta 14C. In general continuity between the methods was assured by slightly 
overlapping Gerard and Rosette sampling where both methods were used and by 
the fact that both analytic techniques use the same standards. On this leg, 
however, one entire station (235) was analyzed by both methods. Table 3 
summarizes the results from that test. The last column in Table 3 is the 
difference (LV-AMS) in the results for the two techniques. For these samples 
the mean difference is +4.7o/oo. This value is remarkably close to the 
expected error in the difference for any two of the measurements based on 
simple propagation of errors. This mean value is not statistically different 
from zero, however the fact that most of the differences are of the same sign 
suggests the possibility of a small systematic error.


TABLE 3: Station 235 Accuracy Check
                                    |  Large Volume   |    AMS     |
                                    |-----------------|------------|
Cast  Bottle  Pressure  Salinity  sf| 14C   sigma Flag| 14C   sigma|delta
----  ------  --------  --------  --|------ ----- ----|------ -----|-----
 3      81      983.7    34.527   2 |-167.7  3.3  2   |-164.2  2.4 |-3.5
 3      83     1232.7    34.560   2 |-189.6  3.0  2   |-191.1  2.1 | 1.5
 3      84     1481.9    34.600   2 |-200.6  2.5  2   |-206.1  2.4 | 5.5
 3      87     1728.4    34.615   2 |-211.1  2.4  2   |-214.4  2.6 | 3.3
 4      85     1812.5      NA     9 |-215.1  2.2  2   |-214.7  2.5 |-0.4
 4      90     1987.5      NA     9 |-220.8  2.5  3(a)|-220.0  3.5 |-0.8
 4      89     1992.9    34.640   2 |-218.3  2.0  2   |-223.7  2.2 | 5.4
 4      93     2231.4    34.653   2 |-219.4  2.2  2   |-225.8  2.6 | 6.4
 4      94     2484.4    34.666   2 |-226.4  2.2  2   |-227.7  2.2 | 1.3
 1      81     3292.8    34.682   2 |-214.9  2.0  2   |-215.2  2.4 | 0.3
 1      84     3542.6    34.684   2 |-209.0  2.1  2   |-221.2  3.4 |12.2
 1      87     3792.6    34.691   2 |-202.6  2.7  2   |-222.2  4.0 |19.6
 1      89     4043.9    34.693   2 |-192.7  2.6  2   |-209.6  3.6 |16.9
 1      93     4297.0    34.706   2 |-188.3  3.7  2   |-194.0  3.0 | 5.7
 1      94     4551.9    34.703   2 |-188.2  3.8  2   |-186.7  2.8 |-1.5
 1      85     4807.1    34.704   2 |-182.2  2.4  2   |-187.8  3.0 | 5.6
 1      90     5066.7    34.705   2 |-178.8  4.1  2   |-181.8  2.3 | 3.0
-------------------------------------------------------------------------
(a) Since both analytical techniques used water from the same sampler, the 
    fact that this result was flagged "questionable" has no bearing on the
    comparison made here. 
 
 
G.4.4    QUALITY CONTROL FLAG ASSIGNMENT

Quality flag values were assigned to all 14C measurements using the code 
defined in Table 0.2 of WHP Office Report WHPO 91-1 Rev. 2 section 4.5.2. 
Measurement flags values of 2, 3, 4, 6 and 9 have been assigned to date. 
Approximately 40 samples remain to be measured. Currently, the unmeasured 
samples are incorrectly coded with a flag value of 9 (no sample collected) 
rather than 1 (sample collected) or 5 (no result reported). The choice between 
values 2 (good), 3 (questionable) or 4 (bad) is involves some interpretation. 
There is very little overlap between this data set and any existing 14C 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 14C data.

When using this data set for scientific application, any 14C datum which is 
flagged with a "3" should be carefully considered. My subjective opinion is 
that any datum flagged "4" should be disregarded. When flagging 14C data, the 
measurement error was taken into consideration. That is, approximately one-
third of the 14C 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 4 summarizes the quality control flags assigned to this data set. For a 
detailed description of the flagging procedure see Key, et al. (1996). As more 
of the Pacific data set becomes available, it is possible that some of these 
flag values may be modified. Any additional data received for this leg will be 
reported to the WOCE office as they become available.


TABLE 4: Summary of Assigned Quality Control Flags

                              Flag  Number
                              ----  ------
                                2    334
                                3      5
                                4      2
                                6      5

G.4.5    DATA SUMMARY

Figures 2-4 summarize the AMS 14C data collected on this leg. Only delta 14C 
measurements with a quality flag value of 2 or 6 are included in each figure. 
Figure 2 shows the delta 14C values with 2sigma error bars plotted as a 
function of pressure for the upper 1.5 kilometers of the water column. This 
gure clearly demonstrates the sampling strategy used during the TUNES legs. 
That is, AMS sampling was almost totally limited to the upper 1500 meters of 
the water column. Large volume sampling using Gerard barrels was used to cover 
the deep and bottom waters. This strategy was chosen primarily because the 
collection cost for AMS14C samples is signicantly less than for the Gerard 
technique. At the time of this cruise, it was known that the AMS technique was 
less precise than the large volume technique, however Figure 2 demonstrates 
that AMS precision is easily sufcient to resolve the vertical gradients in 
delta14C at least in the upper kilometer. The large spread in the data for the 
upper few hundred meters is due to the doming of the isopleths around the 
Equator. Most of the individual proles have a subsurface maximum at 
approximately 200m.

Figure3 shows the delta 14C values plotted against silicate for samples from 
the upper 2 kilometers of the water column. The straight line shown in the 
gure 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 (delta 14C = -70 - Si) represents the relationship between naturally 
occurring radiocarbon and silicate for most of the ocean. They interpret 
deviations in delta 14C above this line to be due to input of bomb-produced 
radiocarbon. Clearly, this relationship is not ideal for the P16C data set. 
The data points having silicate values greater than or equal to 60 mol/kg 
almost certainly have no bomb-radiocarbon component and should therefore lie 
on, rather than below, the line as seen in Figure 3. For these data the slope 
of the line needs to be steeper or/and the intercept needs to be lower. A 
least squares fit of the data from samples between 1 and 2 km depth (n=27; R 
square =.88) gives an intercept of -749 which is easily within error of 
Broecker's -70, but the intercept value of -1.24.09 is significantly steeper 
than the -1. calculated for the GEOSECS global data set.

Figure 4 is an objectively contoured section (LeTraon, 1990) of the delta 14C 
distribution for the upper kilometer of the water column. Obvious in Figure 4 
is the doming of the isopleths toward the Equator and the subsurface location 
of the maximum delta 14C concentration for most of the section. For this 
section the peak of the equatorial doming is shifted to the north by 
approximately 10 degrees.




G.4.6    REFERENCES AND SUPPORTING DOCUMENTATION

Key, R.M., WOCE radiocarbon program reports progress, WOCE Notes, 8(1),12-17, 
    1996

Key, R.M., WOCE Pacific Ocean radiocarbon program, Radiocarbon, submitted, 
    1996.

Key, R.M., P.D. Quay and NOSAMS, WOCE AMS Radiocarbon I: Pacific Ocean 
    results; P6, P16 & P17, Radiocarbon, submitted, 1996.

LeTraon, P.Y., A method for optimal analysis of fields with spatially variable 
    mean, J. Geophys. Res., 95, 13543-13547, 1990.

NOSAMS, National Ocean Sciences AMS Facility Data Report #96-019, Woods Hole 
    Oceanographic Institution, Woods Hole, MA, 02543, 1996.

Peng, T.-H., R. M. Key and H. G. stlund, Temporal variations of bomb 
    radiocarbon inventory in the Pacific Ocean, Marine Chem., submitted, 1996.



FIGURE LEGENDS

Figure 1: 14C station locations for WOCE P16C (TUNES-3). Stations indicated by 
          a dot were sampled only in the thermocline using the AMS technique. 
          Stations indicated by a + were sampled over the entire water column 
          using AMS for the thermocline and large volume sampling for deep and 
          bottom waters.

Figure 2: AMS14C results for P16C stations shown with 2 error bars.Only those 
          measurements having a quality control ag value of 2 are plotted.

Figure 3: delta14C as a function of silicate for P16C AMS samples. The 
          straight line shows the relationship proposed by Broecker,et al., 
          1995 (delta14C = -70 - Si with radiocarbon in o/oo and silicate 
          mol/kg).

Figure 4: delta14C concentration in the upper kilometer of TUNES leg 3; WOCE 
          line P16C) along 155W. Gridding done using the method of Letraon 
          (1990); all samples measured using the AMS technique (Key, 1996a,b; 
          Key,et al., 1996). For most of the section the maximum concentration 
          is found below the surface.



G.5  FINAL CFC DATA QUALITY EVALUATION COMMENTS on P16C.
     (David Wisegarver)
     Dec 2000
 
During the initial DQE review of the CFC data, a small number
of samples were given QUALT2 flags which differed from the initial
QUALT1 flags assigned by the PI.  After discussion, the PI concurred
with the DQE assigned flags and updated the QUAL1 flags for these
samples.

The CFC concentrations have been adjusted to the SIO98 calibration Scale
(Prinn et al. 2000) so that all of the Pacific WOCE CFC data will be on
a common calibration scale.

For further information, comments or questions, please, contact the CFC
PI for this section 
                              J. Bullister
                          (johnb@pmel.noaa.gov) 
                                   or 
                             David Wisegarver
                           (wise@pmel.noaa.gov)

Additional information on WOCE CFC synthesis may be available at:
http://www.pmel.noaa.gov/cfc.

Prinn, R. G., R. F. Weiss, P. J. Fraser, P. G. Simmonds, D. M. Cunnold, F. N.   
       Alyea, S. O'Doherty, P. Salameh, B. R. Miller, J. Huang, R. H. J. Wang, 
       D. E. Hartley, C. Harth, L. P. Steele, G. Sturrock, P. M. Midgley, and 
       A. McCulloch, A history of chemically and radiatively important gases in 
       air deduced from ALE/GAGE/AGAGE. Journal of Geophysical Research, 105, 
       17,751-17,792, 2000.




H    RESPONSES TO DATA QUALITY EVALUATIONS

H.1  Hydrography

     Accepted all DQE suggestions concerning flags except:
        331 #21 salts were not flagged questionable.  
     Other changes:
        Station 221 silcate was changed from 3 to 2.




H.2  RESPONSE TO CTD DQE
     (Lynne D. Talley)
     October 10, 1995


The CTD data from P16C have been rechecked based on the useful and extensive 
comments from Neil White, which were conveyed to me on December 8, 1994.

In your letter you mention the following points, for which we have taken action:

1.  Identification of bad values in the CTD traces and the extensive 
    interpolations, all of which were flagged only as "6" rather than some 
    being flagged "3" or "4": We agree that flags other than "6" should have 
    been used. We have now looked at all interpolations of more than 10 dbar 
    in  temperature, salinity and oxygen, and have made subjective changes to 
    the  flaggings. On one station (sta. 255) the poorly interpolated 
    temperature  and salinity values near the surface have been removed and 
    replaced with - 9. (flag "5").

2.  The temperatures are now being converted to T90 by Jane Baker, who 
    provided  the initial conversion of the WHOI CTD formatted data into WHPO 
    format as a  service to the WHOI CTD group.

3.  The dates of the WHPO CTD stations have been reset to correct dates.

4.  Conductivity calibrations for stations 228 to 245 have been shifted with a  
    station dependent bias to smooth out the .002 to .004 shift in 
    conductivity  between stations 245 and 246.

Neil White's report mentions other points. Here is my response to points other 
than 1-4 above.

5.  Missing oxygen values were reset to -9.

6.  There is apparently no recourse to the flaggings of -9 where one channel  
    was bad, since the WHOI internal data format did not store information for  
    each channel at the time of this cruise.

7.  The even decibars at sta. 251 were a way of flagging it as an upsast. We  
    agree with Neil White that it is more practical to have the entire data 
    set  at either even or odd intervals. The data and number of scans have 
    now been linearly interpolated to odd decibars.

8.  Oxygen units in the documentation are now in umol/kg, except for  
    comparisons with historical data. Because the CTD oxygen data were  
    processed using units of mUI, calibration plots are still in ml/l. (I  
    suspect that the figures will be removed in your final editing of the  
    documentation in any case.)

9.  Quantitative temperature and pressure calibration information is now  
    supplied.

10. The shallow data could have received more attention. Especially bothersome  
    were the bad values at and near the surface in both salinity and oxygen; 
    if the bad salinity values are due to averaging of air and seawater  
    conductivities, then it would have been easier if the software had been  
    able to take this mto account. (The newest versions of WHOI CTD software 
    do  not have this problem.)

11. Station 224 shallow: agreed that there is probably a problem with the  
    bottles, but I can't find any obvious reason. There were no problems noted  
    with bottle firing, the problem did not occur where we went from one  
    rosette to another, there were no apparent duplicate salinity values  
    (suggesting a mistake in sampling), and the nutrients/oxygens are no help.  
    Since there is a real offset, the flags have been changed for the bottle  
    salinities at levels 21 through 26 to 3 (questionable).

12. Stations 225 229, 230, 237, 241, 243, 245: problem is smaller, and no 
    flags  have been changed.

13. Station 262: checked profiles and agree that bottle salinities look too  
    high (0.01 to 0.03) in the range 413617 dbars; CTD data look OK compared  
    with adjacent stations - nothing suggestive of a problem with discrete  
    samples in the log books. The down and up CTD casts have fairly similar  
    shapes, so they were not sampling different water, which could have been  
    another source of error. No change to flags.

14. Station 289: I agree with the assessment of bottle 30 at 252 meters and  
    have changed the discrete oxygen flag to "3".

15. Station 313: It looks like sample 29 was a duplicate draw of bottle 28. 
    The bottle flag for salinity has been changed to "4". Sample 26 could be 
    a  duplicate draw of bottle 25. The bottle flag for salinity has been 
    changed to "3", since it is not as cleat a problem as the bottle 28-29 
    problem.

16. Station 245-246: we agree that the jump from 245 to 246 really is 0.002 to  
    0.004 and not 0.001. The calibration documentation indicating a smaller  
    jump of 0.0015 was appropriate for a group of stations prior to 245 and  
    after 246, rather than those two specific stations. The switch in Autosals  
    between stations 246 and 247 complicated the processing but there was no  
    real shift in autosal salinities at that point (at most a decrease in the  
    noise level). The jump m CTD conductivity starting at 246 was classic -  
    looks like an exponential settling in to the new calibration. Therefore it  
    would be pretty hard to remove. We have not done anything new with the  
    calibration, just tried to clarify the documentation.

17. Station 253 - calibration of this station was problematic, as noted in the  
    documentation. The CTD salinities are flagged "3" throughout - perhaps 
    they  were not in the version which N. White was looking aL

    Station 263 - this seems to be a problem of bad bottle values rather than  
    the CTD, although the latter seems a little low (and bottles ate high).  
    There are no problems listed in the sample log sheets. The salinity at 
    4113  dbar (bottle 2) seems especially out of line since the CTD profiles  
    indicate increasing salinity to the bottom, but this discrete value is  
    higher than the salinity at the bottommost point just below it. Therefore 
    I  have changed the discrete salinity flag to "3".

18. Mean deep-water offset the problem here is that the conductivity 
    adjustment  which was made to improve the very deepest calibration threw 
    off the intermediate depth calibration, as noted in the documentation. 
    The calibration just simply is problematic and not quite to WHP standards 
    for accuracy in the mid-depth range.

19. Oxygen at sta. 319: within the full envelope of CTD and bottle profiles, 
    both the CTD and bottle data at this station look reasonable, and so no 
    change has been made.

I also enclose a copy of the CTD editing comments provided by Maggie Cook, vis a 
vis the changes made to the CTD data set after it was DOEd.



H.2.a  RESPONSE TO HYDROGRAPHY DQE
       (Maggie Cook)
       October 10, 1995

14 June 1995: The following cast number corrections were made to the station 
headers per request of Kai Jancke. The station date in all *.WCT files was 
corrected according to at sea station logs.

                          station   cast #
                          -------   ------
                            235       4
                            244       3
                            246       2
                            249       2
                            254       2
                            259       5
                            266       2
                            287       2
                            288       2
                            293       2
                            300       3
                            308       3
                            314       2
                            317       3

24 Jul 1995: All oxygen values that should have been 11-911 in the *.WCT files 
             have been corrected. They had been scrambled earlier during the 
             conversion of units to ml/l. (stations 221,222,223,224,225,226, 
             251, and 255)
24 Jul 1995: Station 251 has been interpolated to odd rather than even db 
             intervals.
24 Jul 1995: 1 have edited the most recent *.WCT WOCE format data files 
             (which I received from Jane Dunworth) to CTD DQE specifications.


    sta 250  
             set TE and SA values for 3 and 5 db to same as 7 db scan 
             set TE and SA flags to 16' accordingly. 
    sta 251  set 4 db SA value to 35.415 
             set SA flags to '6' accordingly. 
    sta 252  set TE and SA values for 1 and 3 db to same as 5 db scan 
             set TE and SA flags to '6' accordingly. 
    sta 255  interpolate SA from 251 to 263 db and 
             set SA flags to 7. 
             set SA values to -9 from 3 to 181 db. 
    sta 256  set TE and SA values for 1 and 3 db to same as 5 db scan. 
             set TE and SA flags to '6' accordingly. 
    sta 257  make note in final documents (p36) that this 
             station does in fact go to 4901 rather than 4923 db. 
    sta 278  set TE and SA values for I and 3 db to same as 5 db scan. 
             set TE and SA flags to 16' accordingly. 
             interpolate SA from 143 to 151 db. 
             set SA flags to 16, accordingly. 
    sta 279  set SA values for 1 and 3 db to same as 5 db scan. 
             set SA flags to 16, accordingly. 
    sta 287  set TE and SA values for 1 and 3 db to same as 5 db scan. 
             set TE and SA flags to '61 accordingly. 
    sta 304  interpolate SA from 91 to 99 db. 
             set SA flags to 16' accordingly. 
    sta 306  set TE and SA values of 3 db scan to that of 5 db scan. 
             set TE and SA flags to '6' accordingly. note in final documents 
             (P37) that there is no 1db scan. 
    sta 322  set TE and SA values for 3 and 5 db values to same as 7db scan. 
             set TE and SA flags to '6' accordingly.

30 Aug 1995: stations 228 - 245 had the following salinity bias adjustments
             made to them in order to minimize the salinity shift occurring at 
             245-246.

             228      0.0000000e+000
             229     -1.1764706e-004
             230     -2.3529412e-004
             231     -3.5294118e-004
             232     -4.7058824e-004
             233     -5.8823529e-004
             234     -7.0588235e-004
             235     -8.2352941e-004
             236     -9.4117647e-004
             237     -1.0588235e-003
             238     -1.1764706e-003
             239     -1.2941176e-003
             240     -1.4117647e-003
             241     -1.5294118e-003
             242     -1.6470588e-003
             243     -1.7647059e-003
             244     -1.8823529e-003
             245     -2.00000OOe-003

20 Jul 1995: Within the P16C CTD data set there are a number of interpolations 
             over more than 10 dbar. There is a question about how to flag 
             them; shorter interpolations have all been flagged as 116". Here 
             are the choices made (July, 1995 LDT).

Interpolation 225

             Temperature: 643-695:   flag 1131, 
             Salinity :   643-695:   flag 1131, 

Interpolations 226:

             temperature: 3811-3827: keep data, flag 6
             temperature: 4349-4371: keep data, flag 3
             salinity:    3811-3825: keep data, flag 6
             salinity:    4349-4365: keep data, flag 3

Interpolation 235

             Oxygen:      301-321:   keep data, flag 3

Interpolation flags 250: 
 
             salinity:    4785-4843: keep data, flag 4 (interpolated to 
                                     bottom) 

interpolations 251:

             temperature: 2017-2025: leave as is (6) 
             temperature: 3057-3729: keep data, flag as 4
             oxygen:      771-785:   leave as is (flagged 6) 
             oxygen:      2017-4793: keep data, flag as 4
             salinity:    761-789:   leave data, flag as 1131,
             salinity:    1011-1025: leave data, leave flagged as "6"
             salinity:    patches between 1735 and 1781: leave data, 
                                                         leave flag 116"
             salinity:    2017-2025: leave data, leave flag 116"
             salinity:    2061-2089: leave data, flag as 1141,
             salinity:    2457-2459: leave data, flag 6
             salinity:    3047-4045: leave data, flag 4

Interpolation flags 253:

             Oxygen:      2865-2883: keep data, flag 3
             Oxygen:      4647-4667: doesn't look like spike was actually 
                                     removed. flag 4

Interpolations and changes: 

     station 255 
             temperature: 45-207:    delete and replace with -9., flag 5
             Salinity:    1-221:     delete data (replace with -9. and 
                                     indicate flag 5).
             Salinity:    229-235:   delete data and interpolate between 227 
                                     and 237, then flag as 6.
             Salinity:    257-261:   delete and interpolate between 251 and 
                                     267 then flag 6.
             Oxygen:      3111-3131: keep data and flag 6

Interpolation: 257

             Oxygen:      2249-2317: keep data flag 4
             Oyxgen:      2743-2767: keep data flag 4(looks like big offset)   
             Oyxgen:      3837-3857: keep data flag 3
             Oxygen:      4805-4901: keep data flag 4(bottom of cast)

Interpolation: 259

             oxygen:      3515-3531: keep data flag 3

Interpolation: 261

             oxygen:      4137-4185: keep data flag 3

Interpolations 264:

             oxygen:      various patches 1599-1739: looks ok, keep flag 6

Interpolation 268

             salinity:    311-327:   keep data, flag 6

Interpolation 285

             Salinity:    125-163:   keep data flag 3

interpolation 294

             salinity:    1995-5475: keep data, flag 4

Interpolation 322

             salinity:    571-605:   keep data flag 4 
             salinity:    931-945:   keep data flag 3
             oxygen:      571-605:   keep data flag3




I.  DATA PROCESSING NOTES

Date      Contact      Data Type       Data Status Summary
--------  ----------   -------------   ----------------------------------------
03/31/94  White        CTD             Agreed to do DQE
              
04/05/94  Mantyla      NUTs/S/O        Agreed to do DQE
              
04/07/94  Jenkins      He/Tr Shallow   Submitted for DQE 
          The next message (1000+ lines) contains the tritium-helium 
          data for the TUNES 2 leg. Just to reiterate, this is the Thomas 
          Washington cruise that took place in the summer of 1991, covering 
          Pl7c-Pl6c along 135W and 150W respectively. The data are organized 
          as one line per "sample", which may contain tritium, helium or 
          both. -99 represents no data or sample for a variable. The columns 
          are as follows:
          
          Sta, Cast, Bottle, Pressure (db), tritium (TU), sigma-tritium 
          (TU), delta-3He (permil), sigma-delta (permil), conc-Helium 
          (nM/Kg), sigma-conc (nM/Kg), quall, qual2
          
          The quality numbers for tritium (quall) are
            1 = valid sample
            2 = possible under-extraction
            3 = possible contamination
            7 = identity suspected
            9 = no sample
          In this data set, there were no quall values of 2,3 or 7
          
          The quality numbers for helium (qual2) are
            1 = valid sample
            2 = possible under extraction
            3 = possible (air) contamination
            7 = identity suspected
            9 = no sample 
          In this data set, there were no qual2 values of 7
          
          Also, the obvious applies, if a sample value is null (-99) its 
          error, which may not appear as null (-99) is meaningless.
          
          Also, the tritium data has been corrected for a small (.0045 TU) 
          blank due to cosmogenic production during storage.
          
          Finally, I was hoping to finish up a paper that I am working on 
          for this data: I don't mind you using it for demonstration 
          purposes, but-I would hope that its distribution could be 
          restricted over the next 4-5 months until I have had a chance to 
          get it submitted and hopefully reviewed and accepted. Also, it 
          will give me a chance to make one final pass at the data to ensure 
          that there are no problems with it. I hope this is OK.
          
              
07/27/94  Mantyla      NUTs/S/O        DQE Report rcvd @ WHPO
              
08/25/94  Talley       NUTs/S/O        PI Responded to DQE Report
          
09/19/94  White        CTD             DQE Report rcvd @ WHPO
              
12/08/94  Joyce        CTD             DQE Report sent to PI
              
12/14/94  Key          DELC14          DQE Report rcvd @ WHPO
              
01/24/95  Key          DELC14          DQE Report sent to PI
              
01/27/95  Talley       CTD/BTL         Data Public
              
10/10/95  Talley       CTD  Final      DQE Issues Resolved
              
12/14/98  Key          DELC14          Data are Public
              
04/29/99  Quay         DELC13          Data and/or Status info Requested by dmb 
              
01/20/00  Key          DELC14 LV       Final Data Rcvd @ WHPO
              
02/04/00  Kozyr        ALKALI/TCARBN   Final Data Rcvd @ WHPO  DQE Complete
              
04/13/00  Evans        HELIUM/DELHE3   Submitted  See Note:  
          I just ftp'ed 4 files to your /INCOMING directory
              i8nwoce.csv   
              p13woce.csv   
              p16cwoce.csv  
              p19cwoce.csv
          ... of the same form as before, comma delimited columns of  
          station, cast, bottle, %delta He3, delta He3 data flag, molal 
          [He], [He] data flag.
              
06/29/00  Anderson     LVS             Data Reformatted 
          I have formatted the .lvs file for p16c.  I also reformatted the .sum 
          file.  
          
          29 June 2000
          p16csu.txt
          Reformatted .sum file to conform with WHPO standard.
          
          p16clv.txt
          Created .lvs file from file sent by Bob Key.
          
          Left data as reported.  Did not fill decimal places with zeros as 
          that suggests a precision that is better than reported.  
          
          Retained nutrients even though the format description for the .lvs 
          files does not have nutrients.  
          
          Assumed temperature was REVTMP and pressure was REVPRS. 
              
08/02/00  Diggs        BTL             Website Updated:  corrected formatting 
          errors  ALL PARAMS IN BOTTLE FILE: I have corrected the 
          formatting errors in the online bottle file for P16C. A few lines 
          had format overflows or incorrect NO_DATA values which caused the 
          number of columns to be inconsistent from one line to the next. It 
          really caused problems for the Exchange Format conversion tools 
          and the NetCDF conversion tools.
              
09/26/00  Buck         LVS             Website Updated:  Data added to website  
              
11/21/00  Uribe        DOC             Submitted  
          File contained here is CRUISE SUMMARIES and NOT sumfiles.  Files 
          listed below should be  considered WHP DOC files. Documention 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 sumfiles.
          Received 1997 August 15th.
              
06/22/01  Uribe        CTD/BTL         Website Updated  CSV File Added
          CTD and Bottle files in exchange format have been put online.
              
11/16/01  Bartolacci   CFCs            Updated CFC ata Ready to be Merged 
          I have placed the updated CFC data file sent by Wisegarver into the  
          P16c original directory in a  subdirectory called 
                      2001.07.09_P16C_CFC_UPDT_WISEGARVER
          This directory contains data, documentation and readme files. data 
          are ready for merging.
              
01/07/02  Uribe        CTD             Website Updated  CSV File Added  
          CTD has been converted to exchange using the new code and put online.
              
01/22/02  Hajrasuliha  CTD/BTL  Internal DQE completed  See 
          Note:  created .ps files, check with gs viewer. Created *check.txt 
          file
              
04/04/02  Muus         CFCs/He/DelHe3  Data Reformatted/OnLine
          Reformatted data online, New CSV file created  Deep Helium 
          and DelHe3 from John Lupton and revised CFCs from Wisegarver 
          merged and put on-line together with new exchange file. 
          
          Notes on P16C merging     Apr 3, 2002  D.Muus
          
          1. Changed all quality flag "1"s to "9"s. Made QUALT2 same as 
             QUALT1. Salinity, Oxygen & Nutrient DQE suggestions all shown in 
             QUALT1.
          
          2. Merged HELIUM, DELHE3, TRITUM and error values from:
               /usr/export/html-public/data/onetime/pacific/p16/p16c/original/ 
               2000.04.13_P16C_LUPTON-EVANS_He.Ne/p16cwoce.csv.txt
             into bottle file (20000802WHPOSIOSCD)
          
          3. Merged CFCs from
               /usr/export/html-public/data/onetime/pacific/p16/p16c/original/ 
               2001.07.09_P16C_CFC_UPDT_WISEGARVER/20010709.174359_WISEGARVER 
               _P16C/20010709.174359_WISEGARVER_P16C_p16c_CFC_DQE.dat
             into bottle file (20000802WHPOSIOSCD)
          
          4. Made new exchange file for Bottle data.
          
          5. Checked new bottle file with Java Ocean Atlas.
 
08/06/02  Kappa        DOC             PDF file compiled, TST file updated
          Both versions include: cruise report; DQE reports (CTD, BTL, CFCs,
          LVS and C14); chief scientest's responses to DQE reports, and 
          WHPO data processing notes.  PDF version also includes figures and
          links from relevant text passages to figures, tables, appendicies.