A.   CRUISE NARRATIVE (A12)

A.1  Highlights

                         WHP Cruise Summary Information

         WOCE section designation  A12
Expedition designation (ExpoCode)  06AQANTX_4
      Chief Scientist/affiliation  Peter Lemke, AWI*
                            Dates  1992.05.21 - 1992.08.05
                             Ship  R/V POLARSTERN
                    Ports of call  Cape Town, South Africa to
                                   Puerto Madryn, Argentina
               Number of stations  115

                                             34°07.0'S
  Stations' Geographic boundaries  58°25.0'W            17°58.0'E
                                             34°07.0'S
     Floats and drifters deployed  6 drifters
   Moorings deployed or recovered  none

                              Contributing Authors

J.J.M. Belgers  W. Dierking    J.M.J. Hoppema  K.U. Richter  U. Sterr
A. Bochert      M. Drinkwater  M. Kreyscher    H. Rose       J. Sültenfuß
R. Brandt       W. Frieden     S. Mai          T. Rothe      M. Thomas
N. Brunken      C. Garrity     S. Moschner     M. Schröder   T. Viehoff
K. Bulsiewicz   I. Hansen      W. Plep         O. Schulze    A. Wisotzki
H. Diedrich     P. Heil        S. Rasenat      N. Steiner

    *Alfred Wegener Institut für Polar und Meeresforschung • Postfach 1201061
                Am Handelshafen 12 • D-27515 Bremerhaven, Germany
                 Phone: +49-471-4831-512 • FAX: +49-471-4831-425



A.2  Cruise Summary 

A.2.a  Geographic boundaries 

The first section (A12) from Cape Town to Antarctica began at 34°16'S 7°20'E and 
proceeded southwest from there to 4°S 0°E and then followed the Greenwich 
Meridian to 69°42'S. After the work around Antarctica was complete the repeat 
section, SR04, was begun at 70°31'S 9°9'W and proceeded northwest through the 
Weddell Sea to finish at 61°S 58°25'W. 

A.2.b  Stations occupied 

The section A12 along the Greenwich Meridian consisted of 71 deep casts and 8 
biological casts to 300m depth. The section SR04 across the Weddell Sea included 
28 full depths and 6 biological casts to 300m depth. For calibration 2 deep 
casts were taken. The oceanographic program included 101 casts of full 
hydrographic work. Each cast included 24 water samples of temperature, salinity, 
oxygen, silicate, phosphate, nitrate, nitrite and 14 special biological casts. 
Additional tracer measurements were done including tritium, helium, 
chlorofluorocarbons F-11 and F-12, and oxygen isotopes 18O and 16O. 

A.2.c  Floats and drifters deployed 

On 10 and 11 July six drifters (Metocean) in one array took place. Deployment 
positions of these drifters are given in Table 6. Two small drifters, measuring 
only air pressure and air temperature, and two highly instrumented drifters were 
deployed at a distance of 70km to each other along the track of the vessel. Two 
additional small drifters were placed by helicopter in a position nearly 70km 
away perpendicular to the ship's track. The two central drifters are measuring 
the air pressure, the air and the sea surface temperature, the snow height and 
ice temperature profiles with an ice thermistor string. Under these central 
drifters a 250m long underwater thermistor cable is fixed with 30 thermistors 
and also two sensors, measuring pressure, temperature, conductivity and salinity 
of the water in 50m and 250m depth. All drifters use the ARGOS system for data 
transmission. 

A.2.d  Moorings deployed or recovered

On the long ice station a mobile system of current meters was used from a sea 
ice floe. A six hour long time series with a fixed acoustic current meter 1.5 
meter below the sea ice was taken to measure the turbulent fluctuations of 
velocity and temperature in the oceanic boundary layer. The objective of this 
experiment was to investigate whether a rigid construction can be used to 
measure physical signals due to Karman vortices around the instrument, without 
too much noise in the interesting frequency band. The launch and recovery of the 
instrument through a 10cm hole through 2.0m of ice led to unforeseen 
difficulties that greatly reduced the measurement time. Radar reflectors (Table 
5) were deployed to aid ice tracking capabilities. 



A.3  List of Principal Investigators Principal 

            MEASUREMENT           PRINCIPAL INVESTIGATOR  INSTITUTION
            --------------------  ----------------------  -----------
            Salinity              M. Schröder             AWI
            Oxygen                M. Schröder             AWI
            Oxygen isotopes       M. Schröder             AWI
            Nutrients             G. Kattner              AWI
            CFCs                  W. Roether              UNIB
            Helium/tritium        W. Roether              UNIB
            CTD                   M. Schröder             AWI
            Neon                  W. Roether              UNIB
            TCO2                  J.M.J. Hoppema          NIOZ/AWI
            XBTs                  M. Schröder             AWI
            Meteorology           W. Frieden              IMH
            Bathymetry            ---------
            ADCP                  M. Schröder             AWI
            Remote sensing        T. Viehoff              AWI
            Marine Geology        C. Haas                 UNIK
            Biological programme  E.-M. Nöthig            AWI



A.4  Scientific Programme and Methods

Cruise Summary Information Itinerary The expedition ANTX/4, the Winter Weddell 
Gyre Study 1992 (WWGS-92), consisted of two hydrographic sections of the World 
Ocean Circulation Experiment (WOCE), during which vertical profiles of 
temperature, salinity, oxygen, CO2, nutrients and several tracers (tritium, 3He, 
He, 18O, 16O, Ne, Freon-11 and Freon-12) were taken. These activities 
represented the largest part of the oceanographic program. The first section 
(A12) from Cape Town to Antarctica mainly followed the Greenwich Meridian. The 
second section (SR04), a traverse of the Weddell Gyre, extended from Kapp 
Norvegia to King George Island. The section SR04 was taken for the third time 
after September 1989 and December 1990 cruises and, therefore, allows estimates 
of the variability of the water mass production in the southern Weddell Sea. The 
main goals of the oceanographic program were the determination of the baroclinic 
mass transport from the horizontal heat and salt fluxes in the Antarctic 
Circumpolar Current and in the Weddell Gyre, and the water mass modification in 
the southern Weddell Sea. For both sections the oceanographic measurements 
represent the first midwinter realization. 

Polarstern left Cape Town on 21 May 1992 with 42 crew members and 45 scientists 
aboard. The oceanographic program started on 22 May in the morning a few miles 
southwest of Cape Town with the beginning of the section A12. Stations were 
taken with a distance of 30 to 45nm. Above the continental shelf slopes the 
station distance was smaller depending on given depth intervals. 

In the beginning the course led southwest to the Greenwich Meridian passing the 
subtropical front on 27 May at 40°25'S, 10°50'E and the subpolar front on 2 June 
at 45°50'S, 01°04'E. Above the Shannon Seamount (42°59.6'S, 2°20.3'E) two 
pressure gauges were deployed at a depth of about 800m. Steaming south along the 
Greenwich Meridian the first icebergs were sighted on 3 June at 47°30'S. On 5 
June Polarstern crossed the polar front at 51°30'S. North of the polar front the 
biology program started with a daily bongo- or multinet tow. 

The ice edge was crossed on 12 June at 60°56.4'S. The sea ice was mainly pancake 
and grease ice up to 68°S where the ice got thicker and more compact. Here the 
work of the sea ice and remote sensing group started on the ice floes on 17 
June. 

On 16 June the sun set for the polar night. Nevertheless, helicopter work was 
generally possible for two hours during the twilight at noon for taking snow and 
ice samples or obtaining data from the infrared line scanner or the laser 
altimeter in the vicinity of the ship. 

The section A12 was completed on 19 June with the 71st station off the shelf ice 
at 69°42.6'S, 0°40.8'W. Polarstern steamed through the freezing coastal polynya 
towards Neumayer-Station Entering Atka Bay on 20 June the weather conditions 
deteriorated such that a supply of the station with helicopter or skidoo was 
impossible. A depot was put on the sea ice, which was visited from the station 
later during calm weather. Polarstern tried to leave Atka Bay but the pressure 
in the sea ice cover due to the strong easterly winds was too high. It was only 
after a turning of the wind to southeast on 29 June that Polarstern was able to 
escape the dense pack ice in Atka Bay and steam towards Kapp Norvegia. 

After finishing a CTD station off Kapp Norvegia on 1 July a hurricane stopped 
the continuation of the section towards the northwest. Polarstern was forced to 
shut off the engines, and drifted due to continuing strong northeasterly winds 
passively with the sea ice in the coastal current 140nm to the southwest. After 
a turning of the wind towards southwest on 8 July the ship escaped the coastal 
current. On course to the center of the Weddell Gyre six ARGOS-equipped drifters 
and ten radar reflectors were deployed on 10 and 11 July between 69°44'S, 
23°47'W and 68°15'S, 27°35'W. 

The polar night ended on 11 July. The section work continued on the planned 
cruise track on 13 July. Polarstern now entered regions with increased 
concentration of multiyear sea ice with thicknesses of 150 to 250cm. The 
temperature decreased to 32°C such that most leads were frozen. The average 
speed of the icebreaker reduced to 2 knots. Considering the remaining time and 
fuel it was decided on 19 July to leave the planned cruise track in northward 
direction following the lead pattern towards South Orkney. 

On the shelf southeast of South Orkney a three day long ice station took place 
from 21 to 24 July. The oceanographers performed turbulence measurements in the 
mixed layer under the sea ice. Besides the general program of measuring sea ice 
and snow thicknesses and profiles of temperature, salinity and porosity, the sea 
ice group investigated the elasticity of the ice floe - and hence its thickness 
- with seismic methods. The remote sensing group was glad to view the same piece 
of sea ice with their sensors under different weather conditions. The 
meteorologists were able to collect a longer data set for the energy balance at 
the sea ice surface. The first part of the station took place under cold 
conditions (-22°C). Then a passing warm front with Beaufort 10 winds raised the 
temperature up to the freezing point. 

After the long station Polarstern steamed westward north of South Orkney taking 
CTD stations in order to determine the baroclinic flow between South Orkney and 
Elephant Island. The last CTD station was taken on 30 July 1992 above the South 
Shetland Trench north of King George Island at a water depth of 5200m. This 
station with a Freon(tm) blank at depths between 2000 and 3000m was used for 
calibration of the tracer data. A total of 115 stations were taken during the 
cruise. 

The meteorological program focused on the energy balance at the sea ice surface. 
The activities consisted of the determination of the short- and long-wave 
radiation balance, the turbulent fluxes of momentum, sensible and latent heat, 
and the heat conduction through snow and sea ice. The vertical structure of the 
entire troposphere was determined from radio sonde ascents. Six ARGOS-equipped 
drifters were deployed, two of which also measured the vertical temperature 
profiles in atmosphere, snow, ice and upper ocean, snow accumulation and 
salinity at two depths, in addition to position, air pressure and air pressure 
tendency. The goal of the meteorological program was the determination of the 
thermodynamic and dynamic boundary conditions for sea ice growth and motion. 

One of the main components of the expedition was the remote sensing ground truth 
program for the Synthetic Aperture Radar (SAR) and the Along Track Scanning 
Radiometer (ATSR) of the European satellite ERS-1, and four infrared, visible 
and microwave channels of sensors on other satellites. Data of a Real Aperture 
Radar (RAR) on board a satellite of the Russian OKEAN series could not be 
received as planned since a replacement for the defective OKEAN-3 satellite was 
not launched in time. 

Emission, reflection and scattering properties of the sea ice surface were 
determined with infra-red and microwave radiometers and with a scatterometer. 
Ground truth data of sea ice concentration were obtained with a line-scan camera 
operated from a helicopter. The sea ice surface topography (pressure ridges) was 
measured with a helicopter-borne laser altimeter. The main goal of the remote 
sensing program was the improvement of algorithms for determining sea ice 
concentration, motion, ice type and surface roughness on larger scales in space 
and time. These data sets are required to improve our understanding of the 
physics of sea ice and to provide observations to test and verify sea ice 
models. 

Measurements of the physical properties of snow and sea ice included the sea ice 
thickness, vertical profiles of density, salt, temperature, pore size, and 
texture, and the dielectric constant and small-scale (mm-cm) surface roughness. 
These data will be used to better interpret satellite observations. Finally, a 
first attempt was undertaken to determine sea ice thickness with a seismic 
multifrequency reflection method. 

The main goal of the biological program was the plankton ecology within the sea 
ice and the upper ocean. Measurements of the distribution of phyto- and 
zooplankton, of particulate orga-nic carbon and nitrogen and of chlorophyll-a 
were taken, and were compared to the properties of the oceanographic 
environment. 

The chemical measurements consisted of lipid investigations undertaken to obtain 
information on the physiological adaptation of copepods, which represent a large 
fraction of the biomass in the Southern Ocean, with respect to environment and 
nutrient supply. 

Within the geological program surface sediments were investigated between Cape 
Town and the sea ice edge using a minicorer fixed under the CTD-rosette. Data 
from these samples represent the basis for paleooceanographic and paleoclimate 
reconstructions. 

From the sea ice edge up to the Argentinian shelf 23 XBT-profiles were taken, 
and the vertical current shear was recorded continuously with an Acoustic 
Doppler Current Profiler (ADCP). 

During the cruise 170 infrared images of the Weddell Sea region from US weather 
satellites were recorded. At the German receiving station at O'Higgins 400 
passes of the ERS-1 SAR were received. Furthermore, after the cruise daily 
microwave images of the SSM/I will be available. From the comparison of the 
different sensors an improvement of the algorithms for sea ice concentration and 
motion are expected. 

On 5 August 1992 at 6:00 GMT Polarstern arrived at Puerto Madryn as planned. 



A.5  Major Problems and Goals Not Achieved 

After the last CTD station Polarstern steamed into Maxwell Bay off the Chilean 
station "Teniente Marsh", where the crew of the German ERS-l receiving station 
was supposed to board the ship. Unfortunately, the weather was bad. The flight 
from O'Higgins was cancelled, and Polarstern had to leave for Puerto Madryn 
without taking the crew aboard. 



A.6.  Other Incidents of Note 

None noted. 



A.7.  List of Cruise Participants 

TABLE 2: Cruise participants  

                       Name                  Institution 
                       -------------------   -----------
                       Belgers, Jan J.J.M.   NIOZ 
                       Bochert, Axel         AWI 
                       Brandt, Rudiger       IMH 
                       Brey, Heinz           HSW 
                       Brunken, Nicole       AWI 
                       Büchner, Jürgen       HSW 
                       Bulsiewicz, Klaus     UNIB 
                       Dierking, Wolfgang    AWI 
                       Dietrich, Helmut      AWI 
                       Drinkwater, Mark      JPL 
                       Ewald, Horst          HSW 
                       Fahl, Kirsten         AWI 
                       Frieden, Wolfgang     IMH 
                       Garrity, Caren        AWU/AES 
                       Haas, Christian       UNIK 
                       Hansen, Imke          AWI 
                       Heil, Petra           AWI 
                       Holsbeek, Ludo        VUB 
                       Hoppema, Mario        NIOZ 
                       Jahn Petra            AWI 
                       Köhler, Herbert       SWA 
                       Kreyscher, Martin     AWI 
                       Lemke, Peter          AWI 
                       Lohanick, Alan        NRL 
                       Massom, Robert        GSFC 
                       Mai, Stephan          AWI 
                       Moschner, Stephan     AWI 
                       Nöthig, Eva-Maria     AWI 
                       Plep, Wilfried        UNIB 
                       Rasenat, Steffen      AWI 
                       Richter, Klaus-Uwe    AWI 
                       Riewesell, Christian  HSW 
                       Röd, Erhard           SWA 
                       Rose, Henning         UNIB 
                       Rothe, Thomas         IMH 
                       Schröder, Michael     AWI 
                       Schulte, Christian    AWI 
                       Schulze, Olaf         IMH 
                       Spiridonov, Vasili    AARI 
                       Steiner, Nadja        AWI 
                       Sterr, Uta            AWI 
                       Sültenfuß, Jürgen     UNIB 
                       Thomas, Markus        IMH 
                       Viehoff, Thomas       AWI 
                       Wisotzki, Andreas     AWI 



Participating Institutions 

        Abbreviation   Address 
        ------------   --------------------------------------- 

    Federal Republic of Germany 

                 AWI   Alfred-Wegener-Institut 
                       für Polar- und Meeresforschung    
                       Postfach 12 01 61    
                       27515 Bremerhaven 

                 HSW   Helicopter Service Wasserthal GmbH     
                       Katnerweg 43    D-22393 
                       Hamburg 

                 IMH   Institut für Meteorologie und 
                       Klimatologie der Universitat Hannover    
                       Nienburger Strasse 6    
                       30167 Hannover 

                 UNIB  Universitat Bremen     
                       Bibliothekstrasse    
                       28334 Bremen 

                 UNIK  Universitat Kiel     
                       Institut für Geophysik    
                       Leibnizstrasse    
                       2418 Kiel 

                 SWA   Seewetteramt     
                       Deutscher Wetterdienst    
                       Bernhard-Nocht-Str. 76    
                       20359 Hamburg Belgium 

                 VUB   Vrije Universiteit Brussels     
                       Laboratory for Ecotoxicology    
                       Pleinlaan 2    
                       B-1050 Brussel


    Canada 

                 AES   AES/Cress Microwave Group     
                       Petrie 214-York University    
                       4700 Keele Street    
                       North York, Ontario    Canada M3J 1P3 
                       Netherlands 

                 NIOZ  Nederlands Instituut voor 
                       Onderzoek der Zee     
                       P.O. Box 59    
                       1790 Ab den Burg, Texel 


    Russia 

                 AARI  Arctic and Antarctic Research Institute     
                       38 Bering Street    
                       19226 St. Petersburg 


    United States of America 

                 NRL   NOAA Research Laboratory   
                       72 Lyme Road  
                       Hanover, NH 03755 

                 GSFC  NASA/Goddard Space Flight Center   
                       Laboratory for Oceans, Code 61   
                       Greenbelt, Maryland, 20771 

                 JPL   Jet Propulsion Laboratory   
                       4800 Oak Grove Drive  
                       Pasadena, CA 91109 




B.   Underway Measurements 

B.1  Navigation and bathymetry 


B.2  Acoustic Doppler Current Profiler (ADCP) 

Enroute measurements of velocity profiles with an ship-mounted 150 kHz 
RDI ADCP in ice free regions along the Greenwich Meridian 
(2090nm) and across the Drake Passage (680nm) were made. 


B.3  Thermosalinograph and underway dissolved gasses 

Enroute registration of surface temperature and salinity with a vessel mounted 
thermosalinograph (only in regions without sea-ice cover) was done. 


B.4  Expendable bathythermograph and salinity measurements 

Crossing Drake Passage hourly type T7 XBTs, for a total of 23, were 
launched after leaving the ice edge. These data provide useful 
information in connection with previous XBT-cruises and with enroute 
re-gistrations of the ADCP which were run as far as 52°N to calibrate 
the system via bottom tracking. ***XBT locations are needed CEC****


B.5  Meteorological observations 
     (R. Brandt, W. Frieden, T. Rothe, O. Schulze, M. Thomas, S. Mai) 

The main objective of the meteorological program was the investigation of the 
ice/atmosphere interaction in midwinter. The program consisted of the 
determination of all components of the energy budget at the sea-ice surface 
during longer ice stations and short period measurements of the turbulent fluxes 
of sensible heat and momentum at different locations for different surface 
conditions (ice concentration, flow-size distribution, snow- and ice-thickness). 
Particular attention was focused on the spatial variability of the energy 
balance components over larger leads and polynyas as a ground truth information 
for the validation of ERS-1 data. Additionally, aerological soundings were taken 
to obtain information about the vertical thermo-dynamic and kinematic structure 
of the boundary layer and the upper atmosphere. 

Energy budget: 

For the determination of the energy budget the following parameters were 
measured: the radiation budget, the turbulent fluxes of sensible and latent heat 
and the conductive heat flux through the snow/ice cover. In ice-covered areas 
the turbulent flux of latent heat can generally be neglected. In regions of thin 
ice or open water this part of the heat flux was estimated using the appro-
priate bulk formula and shipborne humidity measurements. 

a) Radiation budget 
The measurements of incoming shortwave and long-wave radiation have been 
realized with a pyranometer (CM- 11, Kipp+Zoenen) and a pyrgeometer (Eppley) 
mounted at the ship's boom. The outgoing long-wave radiation was calculated from 
the radiation temperature measured with a radiation thermometer (KT-4). The 
albedo of the surface was also measured with a pyrano-meter (CM- 11). 

All these measurements, except for albedo, were performed continuously beginning 
on 12 June, when the ship reached the ice edge and ending on 29 July. The albedo 
measurements were only made from time to time in periods when the sun was rising 
above the horizon (12-17 June, 11-29 July). Due to problems with the data-logger 
five days of data were loss. In addition to the measurements with the KT-4 the 
outgoing long-wave radiation was measured also with a pyrgeometer (Eppley) 
during the 3 day station from 21-24 July near the South Orkneys. This additional 
data set allows a calibration of the KT-4 measurements. During the long ice 
station all instruments were installed on a sledge, placed on the ice floe in 
vicinity of the vessel. 

As an example, four components of the radiation budget during the long ice 
station were plotted (not shown). The curves demonstrate the dependence of the 
different components on the cloud cover: a clear sky from the beginning of the 
station until the afternoon of 22 July and a following warm front passage with 
an overcast sky until the end of the station, except for 4 hours during the 
night from 23 - 24 July. 

Fig. 2.2-2 (not shown) contains the net short- and long-wave radiation as well 
as the total net radiation during the long ice station. Under clear sky 
conditions the ice surface loses up to 80 W/m2 whereas for overcast sky the 
components compensate each other and no net radiation energy is available at the 
surface. 

b) Turbulent fluxes 
The vertical turbulent fluxes of sensible heat and momentum were derived from 
wind and temperature fluctuations measured during most stations with a sonic-
anemometer-thermometer (Metek) at the ship's boom (sampling frequency 10 Hz). 
Most of the stations lasted several hours from which we finally got 38 short 
period data sets. The measurements were obtained over a variety ice conditions 
like Nilas, Pancake-ice, first-year-ice and over open water. Two longer time 
series were collected during the drifting periods when the ship was stuck in the 
ice in Atka Bay and south of Cape Norwegia. The most important data set was 
obtained from the 3 day station south of the South Orkneys. 

In Figs. 2.2-3 and 2.2-4 (not shown) the turbulent fluxes of sensible heat and 
momentum during the long ice station from the 21-24 July (10 minute averages) 
are displayed. The turbulent flux of sensible heat is highly correlated with the 
air temperature and the cloud conditions. Due to the clear sky and very low 
temperatures at the beginning of the station the heat flux to the surface was 
very small (positive values denote an energy gain, negative an energy loss at 
the surface). The energy gain increased with rising temperatures and an overcast 
sky up to 60 W/qm. The sudden and sharp decrease in the morning of the 24 July 
is due to the clear sky in the night. The turbu-lent flux of momentum depends on 
the surface conditions and mainly on the wind speed. 

c) Conductive heat flux through the ice 
For the calculation of the conductive heat flux a newly-developed thermistor 
stick was put into the ice during the 3 day station to obtain a time series of 
temperature profiles. This thermistor stick allowed the simultaneous 
determination of the ice temperature at seven depth levels ranging from 5cm to 
1.0m below the ice/snow interface. The sampling rate during the measurements was 
1 minute. 

First results are shown in Fig. 2.2-5. (not shown) The profiles chosen 
illustrate the influence of the air temperature on the temperature in the upper 
layers of the ice. During the station the air temperature rose from -22°C to 
about 0°C. Simultaneously the ice temperature in the first few centimeters 
increased from -21°C to -5°C. Moreover the profiles show that at the end of the 
station the temperature at a depth of 0.5m was about 2K higher than at the 
beginning. The light air temperature drop in the night from 23 - 24 July was not 
very pronounced in the ice as can be seen in the profiles. 

From the temperature gradient the heat flux can be calculated using the thermal 
conductivity of the ice, which is mainly a function of the salinity. Salinity 
profiles will be available from the sea ice group. 

A first rough estimation of the energy budget, containing the radiation budget Q 
and the turbulent flux of sensible heat, H, at the long ice station . In the 
beginning of the station the surface loss was nearly 50 W/m2. This energy had to 
be supplied by freezing processes at the bottom of the ice, which finally had to 
be transferred to the surface of the sea ice by the conductive heat flux. Later 
during the station, when the air temperature had increased and the sky was 
overcast, the surface received about 20 to 30 W/m2 from the atmosphere. 

Radio soundings 

In order to get information about the meteorological conditions in the boundary 
layer and the upper atmosphere a total of 169 radio soundings were performed. 
Within the sea ice covered region four soundings per day were taken.

As an example of this extensive data set Fig. 2.2-7(now shown)shows the wind 
direction and the wind speed in the lower stratosphere compared to those at the 
surface level (all soundings at 12:00 UTC from 23 May - 27 July). The mean wind 
direction in the lower stratosphere is around 270, while at the surface level 
two main directions are visible. The more westerly directions were measured in 
open water and in the subtropical zone, the eastward components are mainly due 
to the katabatic surface winds near the antarctic continent. 

Storm events 

During this winter cruise five marked storm events occurred which had a strong 
influence on the ship's operations and the scientific work. The first storm 
developed on 4/5 June at 50°S, 0°E with 11 Beaufort winds. The cyclogenesis was 
driven by advection of positive vorticity at the polar front, and the wind was 
geostrophically balanced. During the storm Polarstern had to stop all station 
work and was forced off course. The second storm event (22 June, 10 Beaufort) 
confined Polarstern to Atka Bay. This time the wind speed could not be explained 
by geostrophy alone, but by an additional strong katabatic wind component. The 
third storm (1 July, 12 Beaufort) forced Polarstern off course into the densely 
packed coastal current. This storm was basically in geostrophic balance. Only 
the gusts of up to 85 knots were probably katabatically induced. 

The fourth storm event (23 July, 10 Beaufort) showed a typical cyclogenesis in 
the western Weddell Sea influenced by low pressure systems dissolving at the 
Antarctic Peninsula. This storm was associated with a warm front which initiated 
a strong temperature change during the long ice station. The fifth storm (31 
July, 10 Beaufort) which seemed to be orographically induced was mainly 
responsible for the failure to take the crew of the German receiving station 
aboard. A summary of the weather conditions during the expedition is shown in 
Table 3 and Table 4. 


TABLE 3: Extrema of several meteorological parameter measured during WWGS-92: 

Parameter                       Maximum/date      Minimum/date 
------------------------------  ----------------  ---------------
air pressure                    1016.1 hPa/22.07  961.2 hPa/11.06 
air temperature                      1.1°C/25.07    -32.0°C/14.07 
wind speed (10 minute mean)        64.3 kn/01.07

Maximum air pressure decrease:  01.07. - 02.07. 47 hPa in 32 hours 
                                (1009 hPa to 962 hPa) 
Maximum temperature rise:       17.07. 23.4 K in 27 hours 
                                (-24.6°C to -1.2°C) 
Maximum temperature decrease:   22.06. 18.3 K in 11 hours 
                                (-5.0°C to -23.3°C)



TABLE 4: Temperature statistics for the cruise track within the ice cover: 

               Number of days with minimum <   0.0°C: 46 
               Number of days with maximum <   0.0°C: 42 
               Number of days with minimum < -10.0°C: 38 
               Number of days with minimum < -20.0°C: 21 
               Number of days with minimum < -30.0°C: 2 
               Number of days with maximum < -10.0°C: 23 
               Number of days with maximum < -15.0°C: 14 
               Number of days with maximum < -20.0°C: 6



B.6  Atmospheric chemistry 



B.7  Remote Sensing  

Several remote sensing techniques including optical, infrared and passive 
microwave sensors as well as active microwave instruments were applied to sea 
ice investigations. The main scientific aim was to link geophysical 
characteristics of Weddell sea ice signatures obtained from various remote 
sensing instruments. These investigations serve as a basis for the 
interpretation of remotely sensed data in terms of sea ice variables needed in 
such a way that signatures may be inverted to extract key ice parameters. These 
ice properties are sought as primary inputs for heat, freshwater and momentum 
flux calculations, along with three-dimensional coupled ocean-ice-atmosphere 
models for the Southern Ocean. Most aspects of these investigations were part of 
the PIPOR Antarctic project for the validation of Synthetic Aperture Radar data 
(SAR) from the European Remote Sensing Satellite ERS-1. 

The main objectives of the passive microwave program were to study the microwave 
emissivity and polarization of various types of new ice, the effect of a snow 
cover on the radiative properties of sea ice and the effect of flooding and the 
presence of slush at the snow/ice interface. In parallel to the remote sensing 
activities the temporal and spatial variability of the physical, morphological, 
chemical, thermal and dielectric properties of snow and sea ice were measured. 

The roughness characteristics of sea ice were measured on different scales to 
construct a data set for validation of sea ice models. Infrared images were 
obtained using the shipborne HRPT receiving station and a number of radar 
reflectors were used to study the large scale ice motion. A data set of floe 
size distribution and lead statistics was acquired using infrared satellite data 
as well as helicopter borne camera data. 

Several sources of remote sensing data were used to derive ice information in 
support of planning navigation, day to day navigation, and scientific 
investigations. 


Measurement of large-scale sea ice motion 
(T. Viehoff, S. Rasenat) 

The shipborne HRPT receiving station was used to collect data from the Advanced 
Very High Resolution Radiometers (AVHRR) as well as data from the so called TOVS 
package system (Tiros Operational Vertical Sounder). During the acquisition 
period the satellite NOAA-9, NOAA-10, NOAA-11, and NOAA-12 were received. About 
10 passes per day were obtained and preprocessed. Out of more than 700 passes 
acquired 170 data sets were selected and stored on tapes for postprocessing. The 
antenna system worked well even under very rough sea state conditions and at 
very low temperatures (< -30 Cry Because of missing daylight at the times of 
overpasses only the infrared channels 3, 4 and 5 of the AVHRR were be used for 
sea ice investigations. The data were radiometrically calibrated and geo-coded 
to allow a direct comparison between different passes. The data will be used to 
describe the large scale ice situation under cloud free conditions. From time 
series of images the motion of the sea ice was determined using a correlation 
method similar to the methods used for SAR data analysis. The inertial motion of 
the ice cover could be measured as well as the mean motion of the ice on time 
scales of 2-5 days . The results were verified by comparison with the drift 
information from the ARGOS buoys located in the Weddell Sea. The data from the 
ARGOS system are included in the HRPT data stream. 

The development of ice shelf edge polynyas were monitored for several cases in 
the Eastern Weddell Sea (0 Meridian to Gould Bay) as well as off the Filchner-
Ronne Ice Shelf. 

A very interesting result of the first preliminary processing of the data was 
the discovery of a number of relative high temperature (> -10°C) patches of 2-
20km in diameter within the sea ice cover in the western and southwestern 
Weddell Sea . These features were monitored over a time period of more then 30 
days. Their locations and extents were nearly stationary over the entire period 
although the surrounding ice cover was moving. The location of at least some of 
these features seem to be correlated with bathymetric features as the shelf edge 
and/or submarine mountains. Nevertheless a more detailed analysis will be 
necessary to de-scribe the physical mechanism responsible for the development of 
these high temperature patches. 

Additionally the data from the ARGOS system were acquired to support the ships 
Meteorological Office with atmospheric information from the drifting buoys in 
the Weddell Sea as well as from all other Argos-equipped stations in the 
vicinity of the Weddell Sea. 

All together 41 NOAA AVHRR images were used for near real time ice support for 
the ship. The information extracted from these data was used to navigate the 
ship through easier ice conditions near the shelf ice edge as well as through 
open water leads and/or young ice and refrozen leads in the inner pack ice. The 
processing of the geocoded infrared images was performed within half an hour 
after acquisition of the passes. Additional software was developed to allow the 
extraction of useful sea ice information by the ship's officers. 


Measurement of infrared brightness temperature 
(R. Brandt , T. Viehoff) 

A 44 day time series of snow/ice- and water-radiance was measured with a KT-4 
radiometer. The data show an instrumental offset of about 4.5°C and an 
additional air temperature dependence. The data have to be corrected for both 
effects. The results will be used to calibrate cloud-free data from the NOAA 
AVHRR infrared channels for atmospheric attenuation effects. 


ERS-1 SAR measurements 
(T. Viehoff) 

In the period I July - 31 July the German Antarctic Receiving Station has 
acquired a large number passes of ERS-1 SAR data. From this data set 246 passes 
had been requested by the AWI remote sensing group. Caused by the heavy ice 
conditions and logistical constraints only four direct comparison could be made 
where the ship was in the SAR swath at the time of overpass. Besides of this a 
number of surface measurements could be performed in a time window ±1 day of the 
overpass. 

Some of the SAR images were transmitted to the ship by fax, but the relative 
poor quality of the fax images prevented an analysis of these data. Due to 
payload faults in the period, 19 July - 24 July, 44 data takes were missing. 
Fortunately the payload could be reactivated to continue the SAR data 
acquisition. 

The receiving station at O'Higgins was supplied with geo-coding information as 
for example frame coordinates etc. to allow a preliminary location of the data 
at the station. The SAR data will be postprocessed at DLR, Oberpfaffenhofen. The 
geophysical interpretation of the data with respect to sea ice motion and 
concentration will be done at the AWI. 


Deployment of radar reflectors 
(W. Dierking, M. Drinkwater) 

Twelve radar reflectors were deployed in order to supplement ice tracking 
capabilities from ERS-1 SAR images (Table 5). The first two reflectors were 
placed on the sea ice to test the reflector design and to check if they could be 
detected in SAR images. Due to unexpected high drift velocities of the sea ice 
these two reflectors could not be covered by the SAR swathes. 


TABLE 5: Deployment-Positions of the Radar Reflectors 

                No.  Latitude    Longitude   Date   Time (UTC)
                ---  ----------  ----------  -----  ----------
                 #l  70°49.95'S  12°26.15'W  01.07    15:00 
                 #2  71°37.48'S  16°33.47'W  05.07    14:00 
                 #3  69°44.10'S  23°46.70'W  10.07    06:30 
                 #4  69°29.90'S  24°24.60'W  10.07    11:20 
                 #5  69°41.96'S  26°15.47'W  10.07    13:00 
                 #6  69°30.04'S  25°49.61'W  10.07    14:30 
                 #7  68°58.70'S  25°41.30'W  11.07    00:30 
                 #8  68°16.30'S  24°59.10'W  11.07    00:30 
                 #9  68°32.60'S  25°45.70'W  11.07    00:30 
                #10  68°59.90'S  27°01.60'W  11.07    00:30 
                #11  68°29.40'S  26°57.00'W  11.07    00:30 
                #12  68°14.60'S  27°34.60'W  11.07    20:30 


The remaining 10 targets were deployed from the ship as well as from helicopter 
together with a set of 6 meteorological ARGOS drifters (Table 6) in an array of 
about 200km in diameter. The main drift component during the period from the 
time of deployment until the end of July was to the northeast which coincides 
with the results of the large scale ice motion extracted from the AVHRR time 
series. The radar reflector array was covered several times by a SAR swath. 
According to a first short analysis done by the O'Higgins operating team the 
targets could be detected in some of the SAR images. However the detailed 
analysis of the displacement of the targets will be done as soon as the SAR data 
are available at AWI. 


TABLE 6: Deployment positions of the Argos drifters 

                 No.  Latitude    Longitude   Date   Time (UTC) 
                ----  ----------  ----------  -----  ----------
                9369  69°44.10'S  23°46.70'W  10.07    06:30 
                9368  69°41.96'S  26°15.47'W  10.07    13:00 
                9365  69°14.50'S  25°02.30'W  10.07    18:00 
                9364  68°43.20'S  26°18.00'W  11.07    09:00 
                9367  68°16.27'S  24°59.11'W  11.07    14:00 
                9368  68°14.60'S  27°34.60'W  11.07    20:30 


Measurement of sea ice concentration and ice types 
(T. Viehoff, A. Bochert) 

The sea ice concentration on small scales was estimated during 13 LineScan 
Camera and/or Video Camera flights. These flights could only be performed during 
daylight conditions with a sufficient amount of contrast at the sea ice surface. 
The LineScan data were analyzed onboard the ship to distinguish between at least 
three classes of ice and open water respectively (Table 2.3-4). The main problem 
of the analysis was to separate between Light Nilas and Grey Ice and to detect 
refrozen melt ponds at the surface of floes which was observed at the end of the 
cruise (flight 1-13) after a significant increase of the air temperature caused 
the snow cover of thinner ice floes to melt. 

The preliminary analysis of the data (Table 7) shows the expected result of very 
high concentrations of white ice in the interior of the Weddell Sea and a more 
distinctive distribution of the ice classes in the Marginal Ice Zones. 


TABLE 7: Measured Sea Ice Type Concentrations (%) 

        Date   Open Water  Dark Nilas   Light Nilas/Grey Ice    White Ice
        -----  ----------  ----------  -----------------------  ---------
        15.6.     29.1        8.6             8.1 (L.N.)          54.2 
        17.6.      0.0        2.9            97.4 (G.I.)           0.0 
        11.7.      0.2        1.0             2.5 (L.N.)          96.2 
        14.7.      0.2        2.3             1.0 (L.N.)          96.4   
        19.7.      1.5        1.9             6.5 (L.N)           88.2 
        26.7.                    has to be analyzed 
        28.7.      0.3        0.0      14.2 (L.N.) 14.6 (G.I.)    70.2 


The Video data were not analyzed on board the ship but were only examined 
visually to support the LineScan data analysis. Positions are shown in Table 8.


TABLE 8: Positions of Video- and Line-Scan Flights 

                No.  Latitude    Longitude   Date    Time (UTC)
                ---  ----------  ----------  ------  ----------
                 l   62°58.47'S  00°00.42'W  13.06.    11:00 
                 2   64°31.50'S  00°00.40'W  14.06.    11:00 
                 3   66°29.97'S  00°00.54'W  15.06.    11:00 
                 4   67°30.40'S  00°00.54'W  16.06.    11:00 
                 5   68°44.20'S  00°04.00'E  17.06.    11:00 
                 6   71°37.48'S  16°33.47'W  05.07.    14:00 
                 7   68°39.92'S  26°47.00'W  11.07.    13:00 
                 8   65°29.61'S  36°12.52'W  14.07.    15:00 
                 9   63°26.07'S  43°31.03'W  19.07.    16:00 
                10   62°05.65'S  43°48.46'W  21.07.    16:00 
                11   62°00.41'S  43°55.69'W  22.07.    13:00 
                12   60°13.51'S  47°09.28'W  26.07.    16:00 
                13   59°50.18'S  50°33.77'W  28.07.    15:00 
                

Measurement of sea ice surface topography 
(W. Dierking, S. Rasenat)  

A laser profiler mounted on a helicopter was used to measure the surface 
topography of sea ice along the cruise leg . The profiles were collected at a 
sampling rate of 100 Hz. Depending on flight conditions, the horizontal 
resolution varied between 15 and 25cm. The effective vertical resolution was 
2cm. At the nominal flight altitude of 30m the laser footprint on ground was 
about 8cm in diameter. Altogether 17 laser flights were per-formed amounting to 
a total profile length of 428nm. 

Between 26 and 29 June, eight 10nm profiles were measured near Atka Bay. During 
this period a nearly stationary area of rafted and ridged consolidated ice was 
separated from drifting pack ice by a shear line approximately located 10nm off 
the shelf edge. Four of the laser profiles were flown parallel to the shear line 
(two on either side) at a distance of 2nm and 4nm, respectively. The other four 
profiles were crossing the shear zone. The height and spacing distributions of 
ice roughness features were investigated separately for the stationary ice area 
between shear line and shelf edge and the drifting pack ice on the other side of 
the shear line. The preliminary results show a nearly exponential decrease of 
ridge frequency as a function of ridge height in the drifting pack ice, whereas 
the histograms of the stationary ice area reveal a Rayleigh-shaped distribution 
function. The mean ridge height, however, is the same on both sides. The mean 
ridge spacing increases with distance off the shear line. In the vicinity of the 
shear line, the average values are 14m for the stationary ice and 19m for the 
drifting ice. At a distance of 4nm from the shear line the values are 25m and 
40m respectively. 

The data sets from 13 - 14 July were analyzed as an example of the topographic 
characteristics in an area of divergent ice drift in the center of the Weddell 
Sea. Both the height and spacing distributions show an exponentially decreasing 
number of ridges as a function of ridge height and spacing, respectively. The 
mean ridge heights are 1.4m and 1.3m, and the mean ridge spacings are 69m and 
62m. Floes of undeformed ice as large as 300 to 700m were observed. A sufficient 
number of open water leads and areas of thin ice were crossed during the flights 
to enable an estimate of the freeboard. The mean freeboard, including the snow 
cover, was 19 and 22cm, respectively. 


Test of NOAA-APT/OKEAN-RAR data acquisition system 
(W. Dierking, T. Viehoff) 

A low cost PC-based APT receiving station designed by the DLR Satellite 
Receiving Station at Neustrelitz for acquisition of OKEAN RAR data as well as 
for NOAA APT data was tested. Unfortunately the acquisition of the OKEAN-4 data 
could not be carried out because of a delay of the satellite launch. The NOAA-
APT data were received and processed successfully. This was done parallel to the 
data acquisition by the ship's Met Office. 


International Space Year (ISY) activities
(C. Garrity, A. Bochert) 

As part of the International Space Year (ISY), ice maps were transmitted by 
INMARSAT facsimile to FS Polarstern during the expedition. The ice information 
originated from two sources: Defense Meteorological Satellite Program (Special 
Sensor Microwave/Imager (SSM/I)) and the European Space Agency Remote Sensing 
Satellite (ERS-1) (Synthetic Aperture Radar (SAR)). The SSM/I brightness 
temperatures (Tg) were obtained directly from the Fleet Numerical Oceanographic 
Center in Monterey, USA to the Alfred Wegener Institute (AWI) using a computer 
modem. The data transfer to AWI was funded by ISY. R.O. Ramseier, who was on 
secondment from AES for one year, processed Tg's using the AES algorithm, 
providing the ship with ice maps of total, thin and old ice concentrations 
within 4-6 hours after the satellite overpass. These maps proved to be very 
useful for planning purposes, especially in order to avoid high concentrations 
of old ice. The SAR data was received directly from the ERS-1 satellite by K. W. 
Asmus and K. Strubing, at a German receiving station located at O'Higgins, at 
the tip of the Antarctic peninsula. The reception of data was successful, 
however, the SAR images received on the ship were poor quality. Only sketches 
showing the interpretation of the original images were of interest. The captain 
did not use the ERS-1 SAR derived ice information for navigation of the ship. 
The SSM/I products combined with images received directly on the ship from the 
NOAA satellites (Advanced Very High Resolution Radiometer (AVHRR) images) proved 
to be a good combination to aid navigation of a ship through the ice. However, 
cloud free conditions were required for the AVHRR images to be useful for ice 
information. 

It is the ultimate aim to combine ice information obtained from the 30m 
resolution SAR with the 25km resolution SSM/I maps. However, further 
understanding of backscatter from snow and ice are required before features on a 
SAR image can be interpreted. It is for this reason that measurements of the 
snow and snow/ice interface, ship-based Tg's and quantitative ice concentrations 
obtained from a helicopter in an area of the satellite footprints were 
completed. 



C.  Hydrographic Measurements  

The objectives of the oceanographic program were: 

• Calculation of volume, heat, and salinity fluxes between Atlantic and Indian 
  ocean and within the regime of the Weddell Gyre. 
• Calculation of the geostrophic shear in the different current bands of the 
  Antarctic Circumpolar Current (ACC) and the Coastal Current (CC) along the 
  eastern and western Antarctic shelf. 
• Definition of water mass characteristics within the circumpolar belt and the 
  Weddell Sea, including the variability of natural and anthropogenic tracers. 
• Detection of the variability of the ACC with an ADCP along the Greenwich 
  Meridian and across the Drake Passage. 
• Description of the variability of the ACC across the Drake Passage with 
  temperature profiles from XBTs and comparison of seasonal changes with other 
  XBT cruises. 
• Measurement of the turbulent heat- and momentum fluxes in the oceanic boundary 
  layer below the sea ice during winter conditions. 


WOCE one-time section A12: 

Oceanographic work started on May 22 with a test station in 2100m water depth at 
the shelf break southwest of Cape Town. After steaming back to the beginning of 
the first transect the routine CTD work began with a normal distance of 40nm 
between stations, decreasing to 15nm at the slopes of the continental shelf 
breaks. Additionally, en route registrations of the ADCP and thermosalinograph 
were done. The ADCP data set had to be carefully analyzed at home whereas the 
surface values of temperature and salinity (at 8m depth) provided a useful tool 
in detecting frontal systems during the cruise. The position of the oceanic 
fronts, the Subtropical Front (STF), the Subantarctic Front (SAF), the Polar 
Front (PF), and the Continental Water Boundary (CWB) were dominated by large 
horizontal gradients in T and S that amount to the following winter values:

                             ∆-Temp (C)  ∆-Salinity (PSU) 
                       ----  ----------  ----------------
                       STF:     7.0           1.0 
                       SAF:     3.5           0.4 
                       PF:      1.5           0.2

Except for the Polar Front these gradients were higher than in the summer season 
(Bathmann U., et al, 1992). In ice covered regions the thermosalinograph did not 
work because of freezing within the pump system. Therefore, values for the 
gradient at the CWB could not be detected. The oceanographic fronts and the main 
water mass characteristics in the Atlantic sector of the Southern Ocean along 
the Greenwich Meridian. The hydrographic parameters of potential temperature 
(E)), salinity (S), phosphate (PO4), and silicate (SiO3) are chosen as examples, 
which can be used to identify the different water masses in this part of the 
ocean. The vertical extent of these water masses can also clearly be seen in CTD 
profiles. North of 56°S, which is the southernmost extension of the mid ocean 
ridge in this area, the different water masses could most easily be traced by 
salinity, whereas in the Weddell Gyre the temperature is the better parameter to 
identify specific water types on a large scale. Looking from north to south the 
upper water column (0-1000m) is dominated by the surface waters of the 
subtropical gyre (north of the STF) and Subantarctic Surface Water (SASW) 
between STF and SAF that are high in salinity and temperature but poor in oxygen 
and nutrients. The belt of strong winds and high precipitation between 
Subantarctic and Polar Front is the source region of the Antarctic Intermediate 
Water (AAIW) which is characterized by low salinity and high oxygen values. This 
tongue sinks towards the north and spreads into the southern Atlantic at a depth 
range of 500- 1200m. In the upper 200m south of the PF the water is cold, fresh, 
rich in oxygen and high in nutrients as compared to the SASW. It is composed of 
Antarctic Surface Water (AASW) and/or Winter Water (WW) which is cooled to the 
freezing point. Near the continent the pycnocline isolating the convective layer 
from the Warm Deep Water (WDW) underneath deepens towards the shelf down to 
600m. At the shelf break less saline waters of the Coastal Current (CC) regime 
appear which have lower oxygen but higher nutrient concentrations as the 
surrounding water masses. Depending on ice conditions and incoming solar 
radiation these values can change rapidly. 

The deep ocean (>1000m) is dominated by the Circumpolar Deep Water (CDW) which 
is the most extensive water mass with a thickness of more than 3000m. It can be 
divided into the Upper CDW (UCDW) with its source in the Indian and Pacific 
oceans which provide its high nutrient and low oxygen values, and the Lower CDW 
(LCDW), which is fed in the North Atlantic Deep Water (NADW) moving southward 
with a maximum in salinity and oxygen and a minimum in nutrients. Entering the 
ACC the axis of both parts is inclined upward to the south compensating the 
northward flowing Antarctic Bottom Water (AABW) which spreads as a tongue of 
cold, fresh water with high oxygen and nutrient values into the great ocean 
basins. It fills the lowest 500m above the bottom north of the mid-ocean ridge 
system at 56°S. In the deep Weddell basin the oceanic structure looks quite 
different because of the large vertical extension of the AABW which is always 
detectable at depths greater than 2000m with a doming in the gyre centre up to 
1200m. It has the largest silicate values of the world ocean with more than 
130.0mmol/l. Near the bottom at depths of more than 4500m the influence of the 
Weddell Sea Bottom Water (WSBW) can be seen from the decreasing temperatures, 
salinities, and silicate values, and increasing oxygen. Pure WSBW was not 
detected on this transect.

Between the WW at the surface and the AABW the warm and salty WDW is trapped 
south of the ACC. It has its origin in the LCDW that circles the cyclonic 
Weddell Gyre at its eastern end and enters the southern part of the Weddell Gyre 
above 1500m (Whitworth and Nowlin, 1987). The heat content of this water mass is 
used to balance the overall heat loss to the atmosphere south of the Polar 
Front. The fronts on the Greenwich Meridian are relatively narrow and their 
signatures are detectable down to greater water depths. Only the Polar Front 
seems to be smeared out over a larger distance. At the Subantarctic Front for 
example the sharp horizontal gradients extend from the surface to the bottom 
(more than 3500m). South of the Polar Front near Station 577 the transition from 
the Antarctic Circumpolar Current to the current regime of the Weddell Gyre is 
also marked by an increase of the shoaling of isolines. Calculated baroclinic 
geostrophic velocities from 50dbar relative to the bottom show the broad 
eastward flowing circumpolar current with three bands of strong geostrophic 
velocities up to 18cm/s at the surface and of more than 3cm/s at 2000m depth. 
The bands are located between SAF and PF. The complicated flow structure north 
of the SAF results from the influence of the Agulhas retroflection, the South 
Atlantic Current (SAC); and the northern limb of the ACC which all form a region 
of very high eddy activity due to strong horizontal current shear and highly 
variable water mass composition. 


Weddell Gyre (WOCE repeat section SR04) 

Because of the severe ice conditions the cruise track in the Weddell Basin had 
to be modified to focus on two hydrographic sections, one starting at the centre 
of the gyre (station 623 at 66°S 33°5'W) running northwest to the South Orkney 
shelf, and the other closing the gap between the shallow (<500m) areas west of 
South Orkney and east of Clarence Island. As known from previous cruises 
(Augstein et al., 1991) doming of isolines in the middle of the cyclonic Weddell 
Gyre (stations 626-629) dominate the structure of all oceanic parameters. The 
downward slope near the shelf break is not as steep as on the eastern boundary 
but is clearly visible. The temperature maximum of the WDW (Q > 0.4°C) is 
divided into two cores where the western cell has its centre position at 44°W. 
This was already sampled in late winter 1989 and summer 1990 by other POLARSTERN 
expeditions (WWGS'89, SWGS'90). 

In the deep ocean Weddell Sea Bottom Water (WSBW) was found between station 624 
and 633. It differs from the water mass above (AABW) through lower temperature 
(Q < - 0.8°C), lower salinity (s < 34.65), lower nutrient values (for example 
silicate less than 125.0RM), and higher oxygen values (Ox > 5.7ml/l). 

The most undiluted WSBW is located of a water depth of 2700-4000m at the 
continental slope as a 100 - 300m thick lens. A second core fills the flat 
bottom of the deep Weddell basin at water depths of more than 4500m. Its 
thickness is also less than 300m. This splitting into two branches suggests that 
different sources of WSBW exist, some of which are known as the Filchner trench 
and the wide shelf areas along the Antarctic Peninsula. Careful interpretation 
of the hydrographic parameters together with the analysis of tracer measurements 
from the water samples should give more information on the pathways and possible 
source areas.

The comparison with previous cruises further south (WWGS'89, SWGS'90, and with 
the American/Russian drift station ISW'92) will improve our understanding of the 
formation mechanisms of WSBW. The northernmost section between the shelves of 
Clarence Island and South Orkney was taken to investigate the possible inflow 
and outflow to/from the Weddell Sea. Due to the limited water depth (maximum 
2400m) no WSBW is leaving the basin through this gap. In the depth range 200 to 
1500m an outflow of WDW out of the Weddell Sea occurs at the eastern flank of 
this section. High temperatures and salinities, and low oxygen values indicate 
that this water originates from the western core of the WDW which is divided by 
the wide and shallow South Orkney shelf.


C.1  Instrumentation 
     (M. Schröder, A. Wisotzki, N. Brunken, I. Hansen, P. Heil, M. Kreyscher, 
     S. Moschner, N. Steiner, U. Sterr, K. U. Richter, H. Diedrich ) 


The instrumentation used included: CTD (NB MkIIIB) General Oceanic Rosette (24 x 
12 1) Salinometer (Autosal) Autoanalyzer (Technicon System II). During the 
long ice station: CTD plus three component acoustic current meter (Simtronix 
UCM-40 Mk II) were used. 


C.2  CTD measurements

The CTD-measurements were carried out with two NB Mark IIIB sondes connected to 
a General Oceanics rosette water sampler with 24 12-liter bottles. Due to 
damaged sensors the CTD-sonde had to be exchanged after station 623. 

The quality of the CTD-data relies on the laboratory calibrations of the 
temperature and pressure sensors made before the cruise at the Scripps 
Institution of Oceanography for each sonde. The performance of the instruments 
during the cruise was controlled by use of SIS digital thermometers and pressure 
meters. The pre-cruise temperature and pressure calibration values were applied 
to the measurements on board (see enclosed calibration table). The conductivity 
values of the CTD were corrected by means of salinity measurements from the 
rosette water samples. Differences between bottle samples and CTD readings for 
each profile were calculated. The stratification of the water column near the 
surface caused higher scattering of these differences and so only values in 
levels deeper than 500m are used for correction. The preliminary data presented 
in this report are corrected by a constant offset of 0.042 (station 535-623) and 
0.062 (station 624-649). The accuracy of the preliminary data was estimated to 
3m°K in temperature, 3dbar in pressure and 0.003 PSU in salinity.


C.3  Water sample salinities

The salinity of the water samples was determined with a Guildline Autosal 8400 A 
salinometer in reference to IAPSO Standard Seawater (batch number P114). The 
salinities are given in PSU and calculated by use of the UNESCO Practical 
Salinity Scale (PSS78).


C.4  Water sample oxygen measurements

The concentration of dissolved oxygen was measured by means of a computer 
controlled SIS Winkler-titrator from 1912 samples taken at 98 stations. In 
addition 10% of all samples were measured as double samples from the same 
bottle. The standard error of all double samples ranged between 0.05 and 0.1µM 
with a standard deviation from 0.2 to 0.5µM corresponding to an overall 
precision of 0.10 to 0.15%.

 
C.5  Dissolved nutrients

Water samples were collected with the oceanographic rosette sampler and analyzed 
on a Technicon Autoanalyzer II system. Nitrate was determined as nitrite after 
reduction with cadmium and reaction with sulfanilamide and N-(1naphtyl)-
ethylendiamindihydrochlorid as red colored azoyde at 20nm. Ammonium was measured 
as blue colored indophenole at 30nm after the reaction with phenolate and 
hypochlorite under alkaline conditions (Berthelot reaction). For the 
determination of silicate and phosphate the compounds react with ammonium 
molybdate by forming a blue molybdate-complex that was measured at 60nm 
respectively at 880nm. All nutrient samples were analyzed in duplicate; 
precision was estimated at 0.1µmol L-1 for nitrate, 0.3µmol L-1 for silicate and 
0.01µmol L-1 for phosphate. The accuracy was set by running four standards at 
the beginning and two standards at the end of each run.


C.6  Chlorofluorocarbons 
     (K. Bulsiewicz, W. Plep, H. Rose, and J. Sültenfuß) 

Along the two hydrographic WOCE sections A12 and SR04 the CFMs Freon-11 and 
Freon-12 were measured using an automated version of the Bullister and Weiss 
technique. The data sets provide important information about circulation and 
renewal pathways for all relevant subsurface water masses. 

Water samples were taken in the usual way using glass syringes. A total of 86 
tracer stations were occupied. 1600 water samples for the fluorocarbons F-11 and 
F-12 were analyzed during the cruise. 

On the WOCE section A12 (Cape Town-Antarctica) CFM-free deep water was found at 
greater depths up to 43°S. With this data and a special calibration cast that 
was made into supposedly CFC free water in the Drake Passage, the overall blank 
can be checked. This is important for the precision of the data, since the 
measurement of water samples require an additional correction for the blank. The 
measurements of these waters showed consistently low values of 0.01-0.02 pmol/kg 
for both CFMs, which is a good value in comparison of the measured range of 
these compounds (approximately 0.1-8 pmol/kg for F-11 and 0.1-3.3 pmol/kg for F-
12).  Measurements of near surface waters under the ice, showed that the 
dissolved CFC concentrations are only about 70% of those predicted for 
equilibrium with the atmosphere. The undersaturation reflects the restriction of 
the air-sea exchange due to the sea ice cover. 

Measurements at stations 623-629 indicate unknown water mass at a depth of 
2200m. This could be a sign of regional convection processes. At station 631 the 
data indicate the presence of high CFC waters (F-11 concentration > 1.8 pmol/kg) 
at a depth ranging between the bottom and about 3850m. This is a clear 
indication of Antarctic Bottom Water. 


C.7  Helium/tritium 
     (K. Bulsiewicz, W. Plep, H. Rose, and J. Sültenfuß) 

Water samples were taken in the usual way using copper tubes (Helium), glass 
bottles (Tritium). For the new technical system to extract helium directly on 
ship, water samples were taken in 50 ml glass pipettes. Samples were collected 
for analysis ashore from 30 stations for tritium (600 water samples) and 47 
stations for helium (880 water samples, 410 with the extraction method). 

 
C.8  The carbon dioxide system in Antarctic waters
     (J.M.J. Hoppema and J.J.M. Belgers) 

Of all gases causing the man-made greenhouse effect carbon dioxide (CO2) is the 
most important one. A significant part of the excess CO2 which is brought into 
the atmosphere is thought to be taken up by the oceans. However, the spatial and 
temporal extent of the uptake is far from manifest. To gain this important 
knowledge the data set of oceanic CO2 measurements has to be enlarged 
significantly. Data collected during the cruise constitute an important 
supplement to the worldwide oceanic data set of CO2, because winter data of the 
Weddell Sea are scarce. Particular objectives were to investigate the following 
features: 

1. Contrary to the temperate and tropical oceans the water column in the 
   Antarctic Ocean has a low vertical stability, which could give rise to 
   important vertical fluxes of CO2. This condition is most pronounced in 
   winter. 

2. The total CO2 (TCO2) content and the alkalinity of a water mass are unique 
   properties, dependent on its history. This renders TCO2 and alkalinity 
   potential tracers. 

3. From TCO2 and alkalinity the partial pressure of CO2 (pCO2) can be 
   calculated. With this property the exchange of CO2 between ocean and 
   atmosphere can be determined. In the ice-covered areas pCO2 can tell 
   something about the CO2 content the water has when it leaves the surface, and 
   thus how much (excess) CO2 is brought down to deeper waters. 

Measurements: 

CO2 in seawater is involved in a series of chemical reactions leading to ionic 
species. Therefore, to measure CO2 in seawater one actually needs to determine 
the CO2 system. It turns out that by measuring 2 parameters of the system one is 
able to calculate the whole system. During the cruise TCO2 and total alkalinity 
were measured. TCO2 was measured with a standard coulometric method. Alkalinity 
was measured by means of a potentiometric acid titration, which consisted of 
first adding an excess quantity of hydrochloric acid beyond the alkalinity 
endpoint and then recording the readings of the pH electrode after some small 
additions of acid. The endpoint was determined with a Gran method. 

Water was taken from the Rosette at almost all CTD stations in Antarctic waters 
during the cruise. For TCO2 24 samples were normally taken through the whole 
water column, with samples in the surface layer more closely spaced; at the 
shallower stations the number of samples was less. Water for alkalinity 
determination was sampled through the whole water column only at selected 
stations, while at the other stations only the surface water layer was analyzed. 
In between stations some continuous on line measurements for TCO2 were 
conducted. 

Fig. 2.1 - l 2 shows three depth profiles for TCO2, two within the Weddell Sea 
and the other one at the Subantarctic Front (SAF) in the Atlantic Ocean. Data on 
the alkalinity will become available later. All profiles show the feature 
usually observed in TCO2 profiles that there is a surface depletion compared to 
the deep water. However, the extent of depletion was different, in the centre of 
the gyre it was much less than at the SAF. This is a combined effect of 
different surface water temperatures and biological activity, which both are 
higher at the SAF. Also in the deep water there were striking differences 
between the profiles. In the Weddell Sea a single TCO2 maximum was observed at 
about 700-900m depth, whereas at the SAF the maximum lies at about 1300m. 
Furthermore, at the SAF TCO2 increases again towards the bottom. Here we see the 
interplay of different water masses of different origin. Between the two Weddell 
Sea stations there were also some slight differences. The TCO2 maximum at 
station 633 was more pronounced than at station 619, while the TCO2 
concentration at the maximum is about equal. Surface TCO2 concentration in the 
centre of the gyre was higher. This suggests that the water in the centre of the 
gyre was in contact with the atmosphere more recently than the water at station 
633. A more detailed analysis of the data will include all stations and will 
also relate to other quantities measured during the cruise. 


C.9  Helium - Neon Isotope Data Documentation (WHP-ID SR4) 
     (Prof. Dr. Wolfgang Roether: Data acquisition) 
     (Christine Rueth: Measurement and data processing)

Two different sets of samples were taken:

1. Most samples were taken in the usual manner with pinched- off copper tubes. 
   After the gas extraktion in Bremen they were measured in the Laboratory with 
   a dedicated Helium - Neon Isotope Mass Spectrometer.

2. Another set was sampled into glas-pipettes and extracted at sea. The glass 
   ampulles with the extracted gas were then transported back to Bremen for 
   measurement. 

All samples were calibrated using an air standard (regular air) in the Bremen 
laboratory. The samples of the whole cruise were measured using the same air 
standard. 

The samples are corrected for tritium decay during storage time, using the 
tritium concentration measured in the tritium samples that were taken from the 
Bremen group as well.

Data quality:
The realtive errors for the measured properties can be given as:

Copper-tube set:
  Helium:  0.36%
  Neon:    0.49%
  He3/He4: 0.31%

Due to different processes the errors of the sea-extracted samples are about 

0.1% enhanced
  Helium:  0.37%
  Neon:    0.50%
  He3/He4: 0.32%


D.  Acknowledgements



E.  References 

Augstein, E., N. Bagriantsev, H. W. Schenke (eds.), 1991: The Expedition 
    ANTARKTIS VIII/1-2, 1989, with the Winter Weddell Gyre Study of the Research 
    Vessels Polarstern and "AKADEMIK FEDOROV". Ber. Polarforsch. 84: 1-134. 
    Bathmann, U., M. Schulz-Baldes, 

E. Fahrbach, V. Smetacek, H.-W. Hubberten (eds.), 1992: The Expedition ANTARKTIS 
    IX/1-4 of the Research Vessel Polarstern in 1990/91. Ber. Polarforsch. 100: 
    1-403. 

Unesco, 1983. International Oceanographic tables. Unesco Technical Papers in 
    Marine Science, No. 44.

Unesco, 1991. Processing of Oceanographic Station Data. Unesco memograph By 
    JPOTS editorial panel.

Whitworth, T. III, W. D. Nowlin, Jr., 1987: Water Masses and Currents of the 
    Southern Ocean at the Greenwich Meridian. J. Geophys. Res., 9 2, 6462-6476.



F.  WHPO Summary

Several data files are associated with this report. They are the ANTX4.sum, 
ANTX4.hyd, ANTX4.csl and *.wct files. The ANTX4.sum file contains a summary of 
the location, time, type of parameters sampled, and other pertient information 
regarding each hydrographic station. The ANTX4.hyd file contains the bottle 
data. The *.wct files are the ctd data for each station. The *.wct files are 
zipped into one file called ANTX4.wct.zip. The ANTX4.csl file is a listing of 
ctd and calculated values at standard levels.

The following is a description of how the standard levels and calculated values 
were derived for the ANTX4.csl file:

Salinity, Temperature and Pressure: 
These three values were smoothed from the individual CTD files over the N 
uniformly increasing pressure levels using the following binomial filter-

             t(j) = 0.25ti(j-1) + 0.5ti(j) + 0.25ti(j+1) j=2....N-1

When a pressure level is represented in the *.csl file that is not contained 
within the ctd values, the value was linearly interpolated to the desired level 
after applying the binomial filtering.  

Sigma-theta(SIG-TH:KG/M3), Sigma-2 (SIG-2: KG/M3), and Sigma-4(SIG-4: KG/M3): 
These values are calculated using the practical salinity scale (PSS-78) and the 
international equation of state for seawater (EOS-80) as described in the Unesco 
publication 44 at reference pressures of the surface for SIG-TH; 2000 dbars for 
Sigma-2; and 4000 dbars for Sigma-4.

Gradient Potential Temperature: 
(GRD-PT: C/DB 10-3) is calculated as the least squares slope between two levels, 
where the standard level is the center of the interval. The interval being the 
smallest of the two differences between the standard level and the two closest 
values. The slope is first determined using CTD temperature and then the 
adiabatic lapse rate is subtracted to obtain the gradient potential temperature. 
Equations and Fortran routines are described in Unesco publication, Processing 
of Oceanographic Station Data, 1991.

Gradient Salinity: 
(GRD-S: 1/DB 10-3) is calculated as the least squares slope between two levels, 
where the standard level is the center of the standard level and the two closes 
values. Equations and Fortran routines are described in Unesco publication, 
Processing of Oceanographic Station Data, 1991.

Potential Vorticity: 
(POT-V: 1/ms 10-11) is calculated as the vertical component ignoring 
contributions due to relative vorticity, i.e. pv=fN2/g, where f is the coriolius 
parameter, N is the bouyancy frequency (data expressed as radius/sec), and g is 
the local acceleration of gravity. 

Bouyancy Frequency: 
(B-V: cph) is calculated using the adiabatic leveling method, Fofonoff (1985) 
and Millard, Owens and Fofonoff (1990). Equations and Fortran routines are 
described in Unesco publication 44.

Potential Energy: 
(PE: J/M2: 10-5) and Dynamic Height (DYN-HT: M) are calculated by integrating 
from 0 to the level of interest.Equations and fortran routines are described in 
Unesco publication, Processing of Oceanographic Station Data, 1991.

Neutral Density: 
(GAMMA-N: KG/M3) is calculated with the program GAMMA-N (Jackett and McDougall) 
version 1.3 Nov. 94. 



G.  Data quality Evulation (DQE)

G.1  DQE of CTD Data: WOCE Section A12 & SR04 in the South Atlantic
     (Eugene Morozov)
     1995.MAY.12

Data quality of 2-db CTD temperature and salinity profiles and reference rosette
samples with oxygen measurements were examined. Vertical distributions and
theta-salinity curves were compared for individual stations using the data of up
and down CTD casts and rosette probes. Data of several neighboring stations
were compared.

Listing of results from the comparison of salinity data. Only those stations are
listed which have data remarks.

STN    PRES   REMARKS
---  -------  ------------------------------------------------------------------
551    69 db  Low SALNTY  (34.405) flag 3
      220 db  Low SALNTY  (34.493) flag 3
      504 db  Low SALNTY  (34.219) flag 3
563   220 db  High SALNTY (34.488) flag 4
      399 db  Low SALNTY  (34.273) flag 3
564   300 db  Low SALNTY  (34.361) flag 4
593           Low CTDSAL calibration almost for the entire station.
              CTDSALs are by 0.002 - 0.003 less than bottle measurements.
595  2401 db  High SALNTY (34.666) flag 3
597  4678 db  High SALNTY (34.653) flag 3
601           CTDSAL calibration is lower than norm.
              CTDSALs are less than bottle SALNTYes by 0.02-0.03 below 2000 db.
602           CTDSAL calibration is higher than norm.
              CTDSALs are greater than bottle SALNTYs by 0.02 - 0.03 below 700 
db. 
              Bottle SALNTY measurements indicate a slight decrease of salinity
              between stations 601 and 602 below 1000 db but CTDSALs do not.
603           CTDSAL calibration is higher than norm.
              CTD SALs are greater than bottle SALNTYs by 0.04 - 0.07 for the 
              entire depth.
610           A shallow station with many bad bottle SALNTY measurements.
                     Pres  up CTDSAL  SALNTY  dwn CTDSAL  SAL flag
                       49   34.208    34.221    34.208       4
                      100   34.210    34.216    34.210       4
                      149   34.210    34.218    34.210       4
                      249   34.211    34.198    34.211       4
                      300   34.211    34.202    34.211       4
                      397   34.223    34.233    34.223       4
618   449 db  Low SALNTY (34.682) flag 4
624  2599 db  Low SALNTY (34.654) flag 3 bottle 9)
625  4199 db  Low SALNTY (34.637) flag 4
626  2599 db  Low SALNTY (34.655) flag 3 and again bottle 9 at the same level
633           CTDSAL calibration is higher than norm below 1000 db.
639           CTDSAL calibration is higher than norm below 1000 db.
642   796 db  Low SALNTY (34.628) flag 3

It is a pity that there were no CTDOXY measurements in the cruise. It is much 
more difficult to make data quality evaluation without continuous measurements. 
Anyhow, I find that some of the bottle OXYGEN fall off the distribution curves:

STN    PRES   REMARKS
---  -------  ------------------------------------------------------------------
539  2399 db  High OXYGEN (247.2) flag 3
540   750 db  Low OXYGEN (184.9) flag 3
541   600 db  Low OXYGEN (193.5) flag 3
552   698 db  Low OXYGEN (226.5) flag 3
556  3399 db  High OXYGEN (234.8) flag 3
     4199 db  High OXYGEN (229.7) flag 3
574  2496 db  High OXYGEN (218.0) flag 3
585  3500 db  Low OXYGEN (235.3) flag 3
591  1200 db  High OXYGEN (218.0) flag 3


INPUT FILE: antx4.EGM
THE DATE TODAY IS: 12-MAY-95


STN  CAST  SAMP   CTD    CTD  CTD
NBR   NO    NO    PRS    SAL  OXY    SAL     OXY   QUALT 1  QUALT 2
---  ----  ----  ------  ---  ---  -------  -----  -------  -------
539   1      3   2399.0                     247.2    ~~~2     ~~~3
540   1     14    750.8                     184.9    ~~~2     ~~~3
541   1     13    600.7                     193.5    ~~~2     ~~~3
551   1     23     69.3            34.4052           ~~2~     ~~3~
551   1     21    220.5            34.4932           ~~2~     ~~3~
551   1     17    504.7            34.2192           ~~2~     ~~3~
552   1     15    698.5                     226.5    ~~~2     ~~~3
556   1      6   3399.0                     234.8    ~~~2     ~~~3
556   1      4   4199.8                     229.7    ~~~2     ~~~3
563   1     19    399.3            34.2736           ~~2~     ~~3~
574   1      1   2496.5                     218.0    ~~~2     ~~~3
585   1      7   3500.4                     235.3    ~~~2     ~~~3
591   2     13   1200.2                     201.9    ~~~2     ~~~3
595   3      7   2401.1            34.6662           ~~2~     ~~3~
597   1      2   4678.7            34.6531           ~~2~     ~~3~
610   1      8     49.2            34.2212           ~~2~     ~~4~
610   1      7    100.4            34.2161           ~~2~     ~~4~
610   1      6    149.9            34.2182           ~~2~     ~~4~
610   1      4    249.4            34.1982           ~~3~     ~~4~
610   1      3    300.0            34.2020           ~~2~     ~~4~
610   1      1    397.5            34.2332           ~~2~     ~~4~
618   3      2    449.8            34.6820           ~~2~     ~~4~
624   1      8   2999.5            34.6548           ~~2~     ~~3~
625   3      5   4199.7            34.6449           ~~2~     ~~4~
626   3      9   2599.3            34.6549           ~~2~     ~~3~
642   1      7    796.4            34.6282           ~~2~     ~~3~



G.2  DQE of Nutrient Data: WOCE Section A12 & SR04 in the S. Atlantic
     (J.C. Jennings, Jr.)
     1995.May.08

The cruise track runs from Capetown, SA southwest to the Greenwich Meridian; 
then south to the Antarctic continental shelf. This is identified as WOCE 
section A12 in the ANTX4.SUM file. Then the track runs northwest to the tip of 
the Antarctic Peninsula, essentially repeating the WWGS89 (ANTVIII/2) and SWGS90 
(ANTIX/?) sections across the central Weddell gyre. This latter part of the 
cruise is identified as SR04.

OVERALL IMPRESSIONS:

There are large meridional property gradients as the southbound cruise track 
crosses the various Subantarctic and Polar frontal features. This is 
particularly evident at about 45°S where the Polar Front is encountered, and in 
the northwestern Weddell gyre where the outflow of very cold and fresh WSBW is 
concentrated.

The comments below are based on an internal comparison of the ANTX4 nutrient and 
dissolved oxygen data made by plotting these parameters against theta and 
pressure in multi-station groups. Our general criterion was to flag as 
questionable the bottle data that plotted outside a multi-station "envelope" by 
more than 1 % of the average deep water concentrations. Thus, phosphate which 
appeared high or low by > 0.03 uM/Kg, nitrate which was off by > 0.35 uM/Kg, 
etc. Almost none of the silicate data was considered questionable. This is 
partly because of the wide range of concentrations encountered in the Weddell 
Sea on this and other historical cruises. We have observed a range of silicate 
concentrations in the WSBW of > 40 uM/Kg in this and other Weddell Sea data, so 
it is difficult to argue that a high or low value near the bottom at a given 
station is questionable.

We also made comparisons of the ANTX4 nutrient and dissolved oxygen data with 
data from three other cruises. Groups of 5 - 10 stations within latitude ranges 
of 2 - 5 degrees were compared using plots of properties versus theta and 
pressure with emphasis on the deep water column where biological activity should 
be minimal. A summary of these comparisons is given in a separate document 
(WSEAHIST.WP for WordPerfect format or WSEAHIST.TXT for the same material in 
ASCII text).


INDIVIDUAL STATION COMMENTS: A12

Station 541: Btls 1 - 7: Low phosphate.                                Flags assigned: 3
Station 542: Btls 3 @ 4195 - 5 @ 3403 db : Low dissolved oxygen:       Flags assigned: 3
Station 544: Btl 9 @ 2198 db: All nutrients low.                       Flags assigned: 3
Station 545: Btl 20 @ 241 db: Low oxygen:                              Flag assigned:  3
Station 553: Btls 5, 6, & 7: All nutrients high on theta and 
                pressure plots. Oxygen looks ok.                       Flags assigned: 3
Station 572: Btl 7 @ 2200 db: High phosphate.                          Flag assigned:  3
Station 573: Btls 1 - 7: Low phosphate and nitrate. No proportional 
                increase in oxygen.                                    Flags assigned: 3
Station 577: Btls 4 @ 3202 db - 6 @ 2501 db: Silicate looks high on 
                theta plot.                                            Flags assigned: 3
Station 580: Btl 9 @ 2204 db: High nitrate.                            Flag assigned:  3
Station 581: Btl 9 @ 2198 db: High phosphate.                          Flag assigned:  3
Station 583: Btls 1 @ 5442 - 7 @ 4203 db: Phosphate looks high on 
                theta plot. Nitrate seems ok.                          Flags assigned: 3
Station 584: Btl 4 @ 4799 db - 11 @ 2800 db: Nitrate looks too high. 
                Phosphate drops at this station.                       Flags assigned (to Nitrate): 3
Station 585: Btl 7 @ 3500 db: Low oxygen on theta plot.                Flag assigned:  3
Station 586: Btls 11 @ 5390 db - 21 @ 1800 db: Nitrate low on 
                pressure an theta plots; outside "envelope" of 
                adjacent station data.                                 Flags assigned: 3
Station 587: Btls 3 @ 5279 - 6 @ 3999: Nitrate looks high.             Flags assigned: 3
Station 590: Btl 12 @ 1200 db: High nitrate.                           Flag assigned:  3
Station 592: Btls 3 @ 4539 db - 5 @ 3800 db: Low nitrate.              Flags assigned: 3
             Btls 7 @ 3000 db and 8 @ 2598 db: Low nitrate.            Flags assigned: 3
Station 594: Btls 3 @ 3775 db - 10 @ 1500 db: Nitrate looks too high:  Flags assigned: 3
Station 595: Btls 2 @ 3340 db - 8 @ 2100 db: Phosphate looks high. 
             Oxygen all silicate look ok.                              Flags assigned to phosphate: 3
             Btls 6 @ 2801 - 8 @ 2100 db: Nitrate looks too low.       Flags assigned: 3
Station 596: Btls 10 @ 2000 db - 13 @ 1000 db: Nitrate looks low on 
                both pressure and theta plots:                         Flags assigned: 3
             Btls 15 @ 700 db - 22 @ 140 db: Nitrate looks low.        Flags assigned: 3
             Btl 11 @ 1800: Phosphate high:                            Flag assigned:  3
Station 598: Btl 8 @ 2500 db: High nitrate:                            Flag assigned:  3
             Btl 17 @ 399 db: Low nitrate:                             Flag assigned:  3
Station 599: Btls 6 @ 3399 db and 7 @ 2999 db: Nitrate looks high by 
                about 0.4 micromoles.                                  Flags assigned: 3
Station 604: Btl 1 @ 2592 db: Low phosphate on theta plot.             Flag assigned:  3
             Btl 3 @ 2401 db: High nitrate:                            Flag assigned:  3
Station 605: Btl 23 @ 40 db: High phosphate.                           Flag assigned:  3
Station 610: Btl 4 @ 249 db: High phosphate.                           Flag assigned:  3
Station 612: All btls: Low nitrate.                                    Flags assigned: 3
Station 619: Btl 10 @ 2179 db: Low nitrate.                            Flag assigned:  3
Station 623: Btls 1 @ 4845 db to 3 @ 4799 db: High nitrate.            Flags assigned: 3
Station 630: Btl 15 @ 799 db: High nitrate.                            Flag assigned: 3
Station 635: Btl 2 @ 628 db: High silicate by about 3 uM/Kg.           Flag assigned: 3
             Btl 15 @ 118 db: Low oxygen, no nutrient data.            Flag assigned: 3
          

INPUT FILE: antx4.jcj
THE DATE TODAY IS: 11-JUL-95

STN  CAST  SAMP    CTD
NBR   NO    NO     PRS   OXYGEN  NITRAT  NITRIT  SILCAT  PHSPHT  QUALT1  QUALT2
541   1      7   2000.0                                   1.66    ~~~~2   ~~~~3
541   1      6   2500.2                                   1.56    ~~~~2   ~~~~3
541   1      5   2998.7                                   1.59    ~~~~2   ~~~~3
541   1      4   3499.7                                   1.67    ~~~~2   ~~~~3
541   1      3   4000.3                                   1.88    ~~~~2   ~~~~3
541   1      2   4344.0                                   1.96    ~~~~2   ~~~~3
542   1      5   3402.6   226.8                                   2~~~~  3~~~~
542   1      4   3800.9   221.5                                   2~~~~  3~~~~
542   1      3   4194.7   218.3                                   2~~~~  3~~~~
544   1      9   2197.5           26.38   0.05    51.10   1.74    ~2222  ~3333
545   1     20    241.1   208.1                                   2~~~~  3~~~~
553   1      7   3000.2           27.96           75.73   1.93    ~2~22  ~3~33
553   1      6   3400.1           30.26           94.26   2.08    ~2~22  ~3~33
553   1      5   3800.7           31.76          106.75   2.21    ~2~22  ~3~33
572   1      7   2200.3                                   2.18    ~~~~2  ~~~~3
573   1      7   1195.2           27.69                   1.88    ~2~~2  ~3~~3
573   1      6   1398.8           27.72                   1.88    ~2~~2  ~3~~3
573   1      5   1600.6           27.84                   1.92    ~2~~2  ~3~~3
573   1      4   1802.4           28.34                   1.93    ~2~~2  ~3~~3
573   1      3   2000.3           28.96                   1.94    ~2~~2  ~3~~3
573   1      2   2127.4           29.32                   1.93    ~2~~2  ~3~~3
573   1      1   2236.7           29.69                   1.87    ~2~~2  ~3~~3
577   1      6   2500.8                           130.20          ~~~2~  ~~~3~
577   1      5   2800.8                           130.15          ~~~2~  ~~~3~
577   1      4   3201.9                           127.85          ~~~2~  ~~~3~
580   3      9   2200.4           33.08                           ~2~~~  ~3~~~
581   1      9   2197.8                                   2.39    ~~~~2  ~~~~3
583   3      7   4203.1                                   2.37    ~~~~2  ~~~~3
583   3      6   4602.0                                   2.34    ~~~~2  ~~~~3
583   3      5   4899.4                                   2.33    ~~~~2  ~~~~3
583   3      4   5289.9                                   2.32    ~~~~2  ~~~~3
583   3      2   5441.2                                   2.34    ~~~~2  ~~~~3
583   3      1   5442.0                                   2.30    ~~~~2  ~~~~3
584   1     13   1800.7           33.32                           ~2~~~  ~3~~~
584   1     12   2202.0           33.17                           ~2~~~  ~3~~~
584   1     11   2800.5           33.46                           ~2~~~  ~3~~~
584   1     10   3399.0           33.54                           ~2~~~  ~3~~~
584   1      8   3397.8           33.61                           ~2~~~  ~3~~~
584   1      7   3800.1           33.52                           ~2~~~  ~3~~~
584   1      6   4198.8           33.65                           ~2~~~  ~3~~~
584   1      5   4598.3           33.65                           ~2~~~  ~3~~~
584   1      4   4799.4           33.29                           ~2~~~  ~3~~~
585   1      7   3500.4   235.3                                   2~~~~  3~~~~
586   3     12   1799.7           32.08                           ~2~~~  ~3~~~
586   3     11   2199.8           31.94                           ~2~~~  ~3~~~
586   3     10   2599.1           31.67                           ~2~~~  ~3~~~
586   3      9   3099.4           31.72                           ~2~~~  ~3~~~
586   3      8   3600.0           31.75                           ~2~~~  ~3~~~
586   3      7   3894.9           31.45                           ~2~~~  ~3~~~
586   3      6   4199.3           31.61                           ~2~~~  ~3~~~
586   3      5   4600.7           31.71                           ~2~~~  ~3~~~
586   3      4   5000.1           31.66                           ~2~~~  ~3~~~
586   3      3   5319.3           31.24                           ~2~~~  ~3~~~
586   3      2   5390.3           31.60                           ~2~~~  ~3~~~
587   1      6   3999.2           33.28                           ~2~~~  ~3~~~
587   1      5   4500.0           33.84                           ~2~~~  ~3~~~
587   1      4   4998.5           33.53                           ~2~~~  ~3~~~
587   1      3   5278.5           33.58                           ~2~~~  ~3~~~
590   1     12   1200.3           34.40                           ~2~~~  ~3~~~
592   3      8   2598.4           32.40                           ~2~~~  ~3~~~
592   3      7   3000.2           32.30                           ~2~~~  ~3~~~
592   3      5   3799.9           31.65                           ~2~~~  ~3~~~
592   3      4   4200.6           31.60                           ~2~~~  ~3~~~
592   3      3   4539.2           32.01                           ~2~~~  ~3~~~
594   1     10   1499.8           34.55                           ~2~~~  ~3~~~
594   1      9   1799.3           35.24                           ~2~~~  ~3~~~
594   1      8   1999.2           34.84                           ~2~~~  ~3~~~
594   1      7   2399.7           34.70                           ~2~~~  ~3~~~
594   1      6   2799.6           33.99                           ~2~~~  ~3~~~
594   1      5   3199.6           33.77                           ~2~~~  ~3~~~
594   1      4   3500.1           34.18                           ~2~~~  ~3~~~
594   1      3   3774.6           34.33                           ~2~~~  ~3~~~
595   3      8   2100.5           32.57                   2.35    ~2~~2  ~3~~3
595   3      7   2401.1           32.47                   2.37    ~2~~2  ~3~~3
595   3      6   2800.9           32.32                   2.35    ~2~~2  ~3~~3
595   3      5   3000.9                                   2.32    ~~~~2  ~~~~3
595   3      4   3101.5                                   2.31    ~~~~2  ~~~~3
595   3      3   3270.3                                   2.34    ~~~~2  ~~~~3
595   3      2   3339.9                                   2.32    ~~~~2  ~~~~3
596   1     22    140.1           31.87                           ~2~~~  ~3~~~
596   1     19    249.0           31.59                           ~2~~~  ~3~~~
596   1     18    299.9           31.16                           ~2~~~  ~3~~~
596   1     17    399.3           31.01                           ~2~~~  ~3~~~
596   1     16    599.5           31.16                           ~2~~~  ~3~~~
596   1     15    699.7           31.25                           ~2~~~  ~3~~~
596   1     13    999.8           31.21                           ~2~~~  ~3~~~
596   1     12   1199.7           31.80                           ~2~~~  ~3~~~
596   1     11   1799.6           31.81                   2.35    ~2~~2  ~3~~3
596   1     10   2001.1           31.92                           ~2~~~  ~3~~~
598   3     17    399.4           31.38                           ~2~~~  ~3~~~
598   3      8   2499.9           34.16                           ~2~~~  ~3~~~
599   1      7   2999.2           33.96                           ~2~~~  ~3~~~
599   1      6   3399.1           33.71                           ~2~~~  ~3~~~
604   1      3   2400.6           33.54                           ~2~~~  ~3~~~
604   1      1   2591.8                                   2.24    ~~~~2  ~~~~3
605   1     23     39.7                                   2.13    ~~~~2  ~~~~3
610   1      4    249.4                                   2.03    ~~~~2  ~~~~3
612   1     24      3.0           26.60                           ~2~~~  ~3~~~
612   1     22     48.2           27.15                           ~2~~~  ~3~~~
612   1     21     70.2           27.19                           ~2~~~  ~3~~~
612   1     20    100.0           26.59                           ~2~~~  ~3~~~
612   1     18    150.0           27.56                           ~2~~~  ~3~~~
612   1     17    200.6           27.67                           ~2~~~  ~3~~~
612   1     15    300.3           27.86                           ~2~~~  ~3~~~
612   1     13    499.7           28.25                           ~2~~~  ~3~~~
612   1     12    499.4           28.23                           ~2~~~  ~3~~~
612   1     11    599.3           28.57                           ~2~~~  ~3~~~
612   1     10    700.3           29.80                           ~2~~~  ~3~~~
612   1      9    750.2           29.26                           ~2~~~  ~3~~~
612   1      8    800.9           29.79                           ~2~~~  ~3~~~
612   1      7    850.4           30.06                           ~2~~~  ~3~~~
612   1      6    900.8           30.68                           ~2~~~  ~3~~~
612   1      5   1000.7           30.91                           ~2~~~  ~3~~~
612   1      4   1100.6           30.02                           ~2~~~  ~3~~~
612   1      3   1199.5           30.58                           ~2~~~  ~3~~~
612   1      2   1349.9           30.55                           ~2~~~  ~3~~~
612   1      1   1430.2           30.75                           ~2~~~  ~3~~~
619   1     10   2179.1           33.29                           ~2~~~  ~3~~~
623   3      3   4799.0           34.15                           ~2~~~  ~3~~~
623   3      2   4845.2           34.15                           ~2~~~  ~3~~~
630   3     15    798.5           34.50                           ~2~~~  ~3~~~
635   1     15    118.1   246.4                                   2~~~~  3~~~~
635   3      2    627.5                           129.98          ~~~2~  ~~~3~



Figure Legends:

Fig. 1.1-1:  Cruise track of RV "Polarstern" during ANT X/4
Fig. 1.3-1a: Plot of air pressure, temperature, wind direction and wind velocity 
             for the time periods 24 May - 19 June 1992
Fig. 1.3-1b: Plot of air pressure, temperature, wind direction and wind velocity 
             for the time periods 19 June - 15 July 1992
Fig. 1.3-1c: Plot of air pressure, temperature, wind direction and wind velocity 
             for the time periods 15 July - 27 July 1992
Fig. 1.3-2:  Wind statistics
Fig. 2.1-1:  ANT X/4 cruise track and station map between Cape Town and 
             Antarctica along the Greenwich meridian
Fig. 2.1-2:  Map of CTD Stations in the Weddell Sea. The broken line denotes the
             planned cruise track.
Fig. 2.1-3:  Surface temperature and salinity measured with the shop's 
             thermosalinograph at 0°E. Marked are the position of fronts: STF= 
             Subtropical Front, SAF= Subantarctic Front, PF= Polar Front, WF= 
             Weddell Front, CWB= Continental Water Boundary.
Fig. 2.1-4a: Section of potential temperature along 0°E together with frontal 
             positions
Fig. 2.1-4b: Section of salinity along 0°E together with frontal positions
Fig. 2.1-4c: Section of phosphate along 0°E together with frontal positions
Fig. 2.1-4d: Section of silicate along 0°E together with frontal positions
Fig. 2.1-5a: Profiles of potential temperature, salinity, dissolved oxygen, and 
             density of station a) 542, and b) 601 which show some of the main 
             water masses and their vertical extent in the Southern Ocean and 
             the Weddell Gyre.
Fig. 2.1-5b: Profiles of potential temperature, salinity, dissolved oxygen, and 
             density of station a) 542, and b) 601 which show some of the main 
             water masses and their vertical extent in the Southern Ocean and 
             the Weddell Gyre.

Fig. 2.1-6:  Overview of the horizontal distribution water masses along 0°E. 
             SASWW: Subantarctic Surface Water, AAIW: Antarctic Intermediate 
             Water, NADW: North Atlantic Deep Water, AABW: Antarctic Bottom 
             Water, CDW: Circumpolar Deep Water (U: upper, L: lower), WW: Winter 
             Water, WDW: Warm Deep Water, WSDW: Weddell Sea Deep Water, WSBW: 
             Weddell Sea Bottom Water. In addition of the position of fronts, 
             ice cover and main currents are shown, where ACC means Antarctic 
             Circumpolar Current and CC is the Coastal Current at the antarctic 
             shelf. In the upper panel the dynamic topography of the surface 
             relative to 1500 dbar is shown.

Fig. 2.1-7:  Distribution of geostrophic velocities along 0°E, calculated for 
             the 50 dbar level relative to the bottom. Isolines of 2, 5, and 10 
             cm/s are shown.

Fig. 2.1-8a: Sections of potential temperature from South Orkney (left) to the 
             center of the Weddell Gyre (right). See also Fig. 2.1-2 for station 
             numbers.

Fig. 2.1-8b: Sections of salinity from South Orkney (left) to the center of the 
             Weddell Gyre (right). See also Fig. 2.1-2 for station numbers.

Fig. 2.1-8c: Sections of silicate from South Orkney (left) to the center of the 
             Weddell Gyre (right). See also Fig. 2.1-2 for station numbers.

Fig. 2.1-9a: Section of potential temperature west of South Orkney. See also 
             Fig. 2.1-2.

Fig. 2.1-9b: Section of salinity west of South Orkney. See also Fig. 2.1-2.

Fig. 2.1-10: Vertical profiles of Freon-11, Freon-12 and the ratio F11/F12 for 
             Station 557.

Fig. 2.1-11: Vertical profiles of Freon-11, Freon-12 and the ratio F11/F12 for 
             Station 627.

Fig. 2.1-12: Three TCO2-depth profiles as obtained during WWGS'92

Fig. 2.2-1:  Outgoing longwave radiation, counter radiation, incoming and 
             reflected shortwave radiation during the long ice station (21 - 27 
             July 1992)

Fig. 2.2-2:  Net longwave, net shortwave and net total radiation during the long 
             ice station.

Fig. 2.2-3:  Turbulent flux of sensible heat during the long ice station.

Fig. 2.2-4:  Turbulent flux of momentum during the long ice station.

Fig. 2.2-5:  Temperature profiles in the ice during the long ice station.

Fig. 2.2-6:  Energy budget (radiation budget and turbulent flux of sensible 
             heat) during the long ice station.

Fig. 2.2-7:  Windspeed and directions at surface level and in the stratosphere 
             from aerological oundings (12:00 UTS; 23.05. - 27.07.92)

Fig. 2.3-1:  Examples of AVHRR derived sea ice velocity fields for the period 
             10.6-12.6.1992.

Fig. 2.3-2:  Time series of sea ice anomalies in the western Weddell Sea for 
             July 1992 observed by AVHRR infrared sensors. The dark spots 
             represent relatively warm areas (-16°C to -20°C) whereas the bright 
             areas have values between -24°C to -34°C.

Fig. 2.3-3:  Cruise track along the polynya off the shelf ice edge near Atka Bay 
             superimposed over an AVHRR infrared image.

Fig. 2.3-4:  Trajectories of the 6 Argos buoys for the period 11.07- 01.10.1992 
             and start positions of the 10 radar reflectors (black triangles).

Fig. 2.3-5:  Positions of the Video Camera flights (dots) and the combined 
             LineScan Camera/Video Camera flights (triangles).

Fig. 2.3-6:  Positions of the Laser-Altimeter flights




WHPO-SIO DATA PROCESSING NOTES

Date      Contact       Data Type      Data Status Summary
--------  ------------  -------------  -----------------------------------------
05/08/95  Jennings-Jr.  NUTs           DQE Report rcvd @ WHPO

05/12/95  Morozov       CTD/S/O        DQE Report rcvd @ WHPO

07/10/95  Lemke         CTD/S/O/NUTs   DQE Report to PI

03/11/99  Klein         CFCs/He/Tr/Ne  Submitted for DQE

06/09/99  Klein         CFCs/He/Tr     Data are Public

08/17/99  Anderson      SUM/HYD        Files Reformatted
          a12su.txt
            Reformatted .sum file:
            • Mostly added and deleted spaces to make the file conform to the 
              WHPO format.
            • Added some 0 (zero) in the lat. and lon. fields to make consistent 
             with the WHPO format.
          12hy.txt
            • Some pressures were not in descending order and I reordered them.
            • File has AMONIUM which does not appear to be a WOCE parameter.
            • Ran over wocecvt and sumcheck with no errors.
          Sarilee Anderson
          17 Aug. 1999

12/13/99  Huynh         DOC            pdf version online

03/10/00  Newton        HELIUM/NEON    quality code problems
          Helium and Neon use a non WOCE quality code scheme. I can translate it 
          and include a translation table in my merging notes, but the 
          originator in her submission of data in March 1999 offered to resubmit 
          using WOCE qual code scheme.

03/10/00  Diggs         SUM/HYD        Website Updated; files online
          I have placed the updated (1999.08.17) files for A12 online and 
          updated all of the html tables accordingly.

03/13/00  Diggs         HELIUM/NEON    Update Needed: flags
          It looks like you're going to have to create the mapping for these 
          flags.

04/18/00  Kappa         Cruise ID      s02 WOCE line designation changed to a12

05/26/00  Huynh         DOC            Website Updated; text version online

11/21/00  Uribe         SUM            Submitted
          Files were found in incoming directory under whp_reports. This 
          directory was zipped, files were separated and placed under proper 
          cruise. All of them are sum files. Received 1997 August 15th.

12/11/00  Uribe         DOC            Submitted
          File contained here is a CRUISE SUMMARY and NOT sumfile. Documentation 
          is online.

06/20/01  Uribe         BTL            Website Updated: Exchange File
          Added Bottle file in exchange format has been linked to website.

06/21/01  Uribe         CTD/BTL        Website Updated: Exchange files
          CTD Exchange File Added, BTL Exchange file modified The exchange 
          bottle file name in directory and index file was modified to lower 
          case. CTD exchange files were put online.

12/19/01  Hajrasuliha   CTD            Internal Data Consistency Check Done
          Created *check.txt file. could not produce .ps file.

12/19/01  Uribe         CTD            Website Updated; Exchange File Added
          CTD has been converted to exchange using the new code and put online.

05/28/02  Anderson      BTL            Data merged into online file
          Merged data submitted by Birgit Klein in March of 1999 into online 
            file. File was located in web site:
            ...a12/original/1999.03.12_A12-SR04_06AQANTX_4.Klein_CFC.HE.TR.NE.
          Merged CFC-11, CF11ER, CFC- 12, CF12ER, TRITUM, TRITER, HELIUM, 
            HELIER, DELHE3, DELHER, NEON, and NEONER.
          Had to e-mail her to clarify some non-WOCE standard QUALT1 flags and 
            units for CFCs. Copies of her e-mails are in my notes file which has 
            been sent to Jerry.
          Here are my notes on A12/SR04 merging:
            Made new exchange file. Both the new exchange file and hyd file have 
              been put online.
            Merged CFC-11, CF11ER, CFC-12, CF12ER, TRITUM, TRITER, HELIUM, 
              HELIER, DELHE3, DELHER, NEON, and NEONER.
            File with these data submitted by Birgit Klein March 11, 1999 web 
              site...atlantic/a12/original/1999.03.12_A12-SR04_06AQANTX_4.KLEIN_
              CFC.HE.TR.NE. File name is reformatted2.txt
            Merged into online file a12hy.txt (19990817WHPOSIOSA) File from 
              Klein had non-WOCE standard QUALT1 flags.
            I e-mailed her asking her to let me know what flags should be used.          
              See copy of her email below.
            I converted the flags as proposed and agreed upon.
            The units for the CFC-11, CF11ER, CFC-12, and CF12ER were labeled 
              _MOL/KG.
            Sent Birgit Klein an e-mail asking her if they were really _MOL/KG 
              or if they are just mislabeled and should say PMOL/KG.
            Changed units for CFC-11 and CFC-12 to PMOL/KG.
            See e-mail from Birgit Klein below.

          On Fri, 17 May 2002 10:32:58 +0200 Birgit Klein wrote:
            thanks for your mail, I am glad the data get finally merged. I agree 
            with your conversions of our flags to WOCE standards. I should have           
            resubmitted the data with proper flags, thank you for doing this 
            job.

05/28/02  Anderson      BTL            Data merged into online file (continued)
          Sarilee Anderson wrote:
          In March of 1999 you sent a data set to the WHP office here at 
            Scripps. I am in the process of checking all data sets for 
            completeness and find that the data you sent has not been merged 
            into the online file. 
          In your e-mail to Steve you indicate that some of the quality flags 
            are non-WOCE standards. We need WOCE standard flags. Would you look 
            at the attached ascii file and let me know what flags I should use 
            for the data?
          I propose for the helium and neon to use
            5 where you have 1
            4 where you have 7
            2 where you have 8
          For the CFCs
            2 where you have 1
            3 where you have 7
          Please let me know if you agree with what I propose. If not, please 
          let me know what you would like done.

09/25/03  Kappa         DOC            Updated online text and pdf files
          • Replaced WHPO-generated station location plot with clearer version
          • Corrected German proper names by adding umlauts
          • Corrected WOCE Line designation by adding SR04
          • Relocated Helium - Neon Isotope Data Documentation for WOCE section 
              SR04 to Section C: HYDROGRAPHIC MEASUREMENTS. Previous version 
              listed NEON as "Not Measured".
          • Added color to PDF doc's internal links
          • Graphic reformatting of doc and figs
          • Added these WHPO-SIO Data Processing Notes

