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CRUISE REPORT: ARKXII
(Updated JUN 2010)



A.  HIGHLIGHTS

A.1.  CRUISE SUMMARY INFORMATION

          WOCE Section Designation  ARKXII
Expedition designation (ExpoCodes)  06AQ19960712
                  Chief Scientists  Ernst Augstein/AWI
                             Dates  12 JUL 1996 - 23 SEP 1996
                              Ship  R/V Polarstern
                     Ports of call  Bremerhaven, GER - Murmansk, RUS - 
                                    Bremerhaven

                                               86°27.8' N
             Geographic Boundaries  65°50.5' E            161°40.8' E
                                               77°59.5' N

                          Stations  103
      Floats and drifters deployed  8 surface buoys deployed
    Moorings deployed or recovered  3 moorings recovered
                        Chief Scientist's Contact Info:
Prof. Dr Ernst Augstein • Alfred-Wegener Inst. für Polar und Meeresforschung
    Postfach 1201061 • Columbusstrasse • Bremerhaven, D-27515 • GERMANY
           Tel: 49-471-4831-400 • Fax: +49-471-4831-149 or -425 
                   Email: eaugstein@awi-bremerhaven.de


                          The expedition ARCTIC '96
                         of RV "Polarstern" (ARK XII)
                 with the Arctic Climate System Study (ACSYS)
                    Ernst Augstein and Cruise Participants
                         Ber. Polarforsch. 234 (1997)
                               ISSN 0176 - 5027
                                  ARCTIC '96





CRUISE REPORT/FAHRTBERICHT

1. Zusammenfassung

Die Expedition ARCTIC '96 wurde von zwei Forschungsschiffen, der deutschen 
Polarstern und der schwedischen ODEN unter Beteiligung von Wissenschaftlern und 
Technikern aus Deutschland, Finnland, Großbritannien, Irland, Kanada, Norwegen, 
Rußland, Schweden und den Vereinigten Staaten von Amerika durchgeführt Das 
gemeinsam entworfene multidisziplinäre Forschungs- Programm wurde unter 
Berücksichtigung der spezifischen zeitlichen und logistischen Anforderungen der 
einzelnen Arbeitsgruppen unter den beiden Schiffen passend aufgeteilt. Demgemäß 
bildeten auf der ODEN die geologischen, geophysikalischen und luftchemischen 
Arbeiten sowie die Eisfernerkundung das Schwergewicht, währen auf der Polarstern 
vorrangig Messungen zur physikalischen, chemischen und biologischen 
Ozeanographie, Atmosphärenphysik und der Erforschung des Meereises vorgenommen 
wurden.

Die physikalischen Projekte auf der Polarstern dienten überwiegend der 
Unterstützung der Arctic Climate System Study (ACSYS) des Weltklimaforschungs- 
Programms, die auf die Erforschung der vorherrschenden ozeanischen, 
atmosphärischen, kryosphärischen und hydrologischen Prozesse der Arktisregion 
ausgerichtet ist. Dabei soll der Beschreibung und numerischen Modellierung der 
Zirkulation, Wassermassenmodifikation sowie der Transporte von Energie und 
Stoffen im Nordpolarmeer einschließlich seiner Randmeere besondere 
Aufmerksamkeit gewidmet werden. Im Hinblick auf diese Ziele wurden auf 
Polarstern Messungen durchgefühurt um.

• die hydrographischen Strukturen des Ozeans auf der Schnittlinie von Franz- 
  Joseph-Land nach Severnaya Zemlya zu erfassen und den Wassermassenaustausch 
  zwischen den flachen sibirisch-europäischen Schelfmeeren und dem tiefen 
  Nordpolarmeer durch den St. Anna- und den Voronin-Trog abzuschätzen
• die Ozeanzirkulation in dem Nansen- und Amundsen-Becken quantitativ zu 
  beschreiben unter besonderer Beachtung der topographischen Einflüsse des 
  Lomonossow Rückens und anderer Bodenstrukturen.
• die zeitlichen Variationen der Strömungen entlang des Kontinentalabhangs 
  und über dem Lomonossow Rücken sowie der mit ihnen verknüpften Wärme- und 
  Salztransporte festzustellen.
• den atmosphärischen Antrieb des Meereises bei verschiedenen großräumigen 
  Luftströmungen zu bestimmen.
• statistisch signifikante Aussagen über die Dicke und die Morphologie des 
  Meereises in verschiedenen Regionen des Nordpolarmeeres zu ermöglichen.

Neben diesen auf die ACSYS bezogenen Arbeiten wurden Beobachtungen zum Studium 
der Meereislebewesen, der regionalen Verteilung des Phyto- und Zooplanktons und 
die Analyse bedeutsamer chemischer Prozesse in unterschiedlichen 
Zirkulationsästen des Nordpolarmeeres vorgenommen. Zu diesem Zweck wurden 
Messungen vom Schiff aus, mit Hilfe von Hubschraubern und auf dem Meereis mit 
verschiedenen teilweise neu entwickelten Instrumenten durchgeführt.  Die 
physikalischen und chemischen Daten dienen unter anderem auch der Überprüfung 
und Verbesserung von Ozean-, Meereis- und Klimamodellen.

An Bord der Polarstern befanden sich 43 Seeleute, ein russischer Eislotse und 53 
Wissenschaftler und Techniker aus Deutschland (29), Schweden (7), Rußland (6), 
USA (5), Kanada (3), Finnland (1), Irland (1) und Großbritannie (1).  Das 
Meßprogramm wurde von multinationalen Arbeitsgruppen durchgeführt die später 
auch die Datenaufbereitung und wissenschaftliche Bewertung der Ergebnisse 
gemeinsam vornehmen werden. Die Zusammenarbeit zwischen der ODEN und der 
Polarstern währen der Expedition bezog sich im wesentlichen auf logistische 
Unterstützung Währen zweier Treffen auf See fand ein Personalaustausch statt und 
es wurden Instrumente und Treibstoff umgeladen. Zur gegenseitigen Information 
über den Arbeitsablauf, die Wetter- und Eisverhältnisse wurden täglich 
Funkgespräche zwischen den wissenschaftlichen Leitern und den Kapitänen beider 
Schiffe geführt

Polarstern lief am Freitag, den 12. Juli 1996 aus Bremerhaven aus und erreichte 
nach einer ruhigen Seereise am 19. Juli den russischen Hafen Murmansk, wo sich 7 
russische und ein finnischer Wissenschaftler sowie 2 Eislotsen einschifften. 
Repräsentanten der Behörden und wissenschaftlichen Einrichtungen der Stadt 
besuchten am Nachmittag des 19. Juli das Schiff anläßlich eines kleinen 
Empfangs. Am 20. Juli verließ Polarstern Murmansk mit dem Ziel Karasee. Außerhal 
der 12-Meilenzone wurde noch einmal Treibstoff von einem Tankschiff übernommen 
um für den langen Aufenthalt im eisbedeckten Nordpolarmeer gut gerüstez u sein. 
Die Packeisgrenze wurde am 23. Juli bei 78°N überquert einen halben Tag vor dem 
ersten Treffen mit der ODEN, die bereits einige Tage in der Barentssee Messungen 
durchgeführ hatte. Währen die Schiffe für einige Stunden zusammen drifteten 
wechselten ein Eislotse und ein Wissenschaftler von der Polarstern zur ODEN 
währen der für beide Schiffe zuständig russische Beobachter in umgekehrter 
Richtung zur Polarstern überstieg Ferner wurden der ODEN einige aus Deutschland 
mitgeführt Geräte übergeben

Nach einigen Stunden Fahrt im Konvoi trennten sich die Schiffe am 24. Juli 1996, 
indem die ODEN ihren nordwärtigen Kurs zum Lomonossow-Rücken fortsetzte und 
Polarstern nach Osten steuerte, um das Meßprogramm mit einem zonalen 
hydrographischen Schnitt zwischen Franz-Joseph-Land und Severnaya Zemlya 
aufzunehmen (Figure 1). Dort wurden mit einer CTD (conductivity, temperature, 
depth) - Sonde, einem Wasserschöpfsystem und einem ADCP (acoustic doppler 
current profiler) der thermohaline Aufbau und mit Einschränkungen das 
Strömungsfeld auf einer Schnittfläche durch den St. Anna- und Voronin-Trog in 
relativ dichten Abständen erfaßt Ferner wurden Wasserproben zur Bestimmung 
ozeanischer Spurenstoffe, radioaktiver Isotope und verschiedener Nährstoffe 
geschöpft sowie Planktonnetzfänge vorgenommen. Längere Meßstationen wurden - wie 
während der gesamten Reise im Eis - für umfangreiche Meereisbeprobungen genutzt, 
um an Bord oder später in den Heimatlabors physikalische, chemische und 
biologische Analysen durchzuführen. Insbesondere konnten auf längeren Traversen 
über große Schollen mit einem neuen Meßsystem statistisch signifikante 
Eisdickenverteilungen registriert werden und Eisrücken detailliert vermessen 
werden. Schließlich dienten die von einem Hubschrauber getragene Turbulenzsonde 
HELIPOD und ein am Bugkran befestigter mit 5 Turbulenzsonden ausgerüsteter 
Profilmast zur Erfassung der vertikalen turbulenten Impuls-, Wärme- und 
Wasserdampftransporte. Hubschrauberflüge in verschiedenen Höhen konnten auch zur 
Bestimmung von Vertikalprofilen der turbulenten Flüsse und deren spektralen 
Verteilung bis zum Oberrand der atmosphärischen Grenzschicht genutzt werden. 

Auf dem Wege nach Severnaya-Zemlya nahm die Eiskonzentration ständig zu und 
behinderte schließlich das Fortkommen des Schiffes so stark, daß Polarstern etwa 
30 sm nach Norden ausweichen mußte um den östlichen Kurs über die Tröge am 1. 
August 1996 bei 82°N / 90°E vollenden zu können. Nach Ausbringen er ersten 
automatischen meteorologischen Driftboje wurden zunächst der Kontinentalabhang 
und dann das Nansen Becken, der Mittelozeanische Rücken und das Amundsen Becken 
in nordöstlicher Richtung überquert. Dabei wurde das auf der Zonaltraverse 
begonnene Meßprogramm im wesentlichen in gleichartiger Weise fortgesetzt. Auf 
dem Weg nach Norden nahm die Eiskonzentration unerwartet deutlich ab, so daß 
Polarstern auf den Fahrtstrecken zwischen den ozeanographischen Stationen in 
breiten Rinnen bisweilen Geschwindigkeiten bis zu 12 kn erreichte. Dadurch 
wurden nicht nur die Zeitverluste des ersten Abschnittes schnell aufgeholt 
sondern auch eine Erweiterung des Meßprogramms vor allem an den Flanken der 
Tiefseerücken ermöglicht. Dabei wurde u. a. gefunden, daß der Mittelozeanische 
Rücken zwischen dem Nansen- und Amundsen-Becken zumindest auf der Polarstern-
Route in den Echolotmessungen - im Gegensatz zu der uns verfügbaren Seekarte - 
nicht in Erscheinung trat.

Wegen der günstigen Eisverhältnisse erreichte Polarstern die Bohrposition der 
ODEN auf dem Lomonossow-Rücken drei Tage früher als geplant, so daß die zweite 
Begegnung beider Schiffe auf den 11./12. August vorverlegt wurde. Aufgrund der 
besonders günstigen Eislage einigten sich Wissenschaftler und Kapitäne darauf, 
die Aufnahme von drei Verankerungen am Nordrand der Laptev- See der Polarstern 
allein zu überlassen und die Fahrtroute der ODEN durch Verlagerung des 
Arbeitsgebiets nach Norden abzuändern. Zur Vermeidung von Treibstoffengpässen 
wurde Schiffsdiesel von der ODEN zur Polarstern und Hubschraubertreibstoff in 
umgekehrter Richtung transferiert. Der russische Beobachter nutzte das Treffen, 
um wieder auf die ODEN zurückzukehren nachdem er einen russischen 
Wissenschaftler beauftragt hatte, die Beobachterfunktion auf Polarstern zu 
übernehmen. Polarstern setzte am 12. August den hydrographischen Schnitt vom 
Amundsen-Becken über den Lomonossow-Rücke fort und erreichte am 15. August das 
Makarov-Becken.

Die anschließende Marschfahrt nach Süden war wieder durch breite Rinnen 
begünstigt so daß die gewonnene Zeit für ein erweitertes Meßprogramm auf der 
südlicheren Traverse über den Lomonossow-Rücken genutzt werden konnte. Im 
Amundsen-Becken wurde ein Meßnetz von meteorologischen und ozeanographischen 
automatischen Driftstationen auf dem Meereis ausgelegt, das über eine längere 
Zeit den atmosphärischen Antrieb und die ozeanischen Größen in der oberen 
Wassersäule im Zentrum des Transpolaren Eisdriftstroms messen soll. Auf der 
Strecke zu den drei Verankerungen in der Umgebung des Kontinentalhanges und des 
südlichen Lomonossow-Rückens verdichtete sich die Eiskonzentration so stark, daß 
die hydrographischen Messungen im nördlichen Verankerungsgebiet sogar teilweise 
reduziert werden mußten. Trotz der ungünstigen Eisbedingungen gelang es, alle 
drei Verankerungssysteme in verhältnismäßig kurzer Zeit sicher zu bergen. Dieser 
Erfolg beruht zum einen auf der guten technischen Konzeption der Verankerungen 
und zum anderen auf dem geschickten Handeln der erfahrenen Schiffsführung und 
der verantwortlichen Wissenschaftler und Techniker. Der Zeitgewinn beim Bergen 
der Verankerungen ging zumindest in Teilen durch weiter anhaltende 
Fahrtverzögerungen im Preßeis wieder verloren. Neben kürzeren Zwangsstillstände 
blieb Polarstern einmal 14 Stunden zwischen zusammengepreßten Schollen stecken.

Glücklicherweis war die Region gerade zu dieser Zeit wolkenarm, so daß den an 
Bord empfangenen Satellitenbildern nützliche Informationen über die 
Eisverteilung entnommen werden konnten. Danach hatten sich um 100 km lange 
Rinnen in Fahrtrichtung des Schiffes gebildet, die ein leichtes Vorankommen 
durch das im übrigen stark gepreßte Eis versprachen. Hubschraubererkundungsflüge 
bestätigten diesen Befund, so daß Polarstern nach zunächst aufwendigem Rammen 
innerhalb von zwei Tagen die Eisrandzone erreichen konnte. Hier stand wieder 
ausreichend Zeit für umfassende Messungen aller Disziplinen zur Verfügung. 
Insbesondere wurden die biologischen Beprobungen verdichtet und die 
Untersuchungen zur atmosphärischen Grenzschichtturbulenz ausgedehnt.

Nach Abschluß des gesamten Meßprogramms am 5. September 1996 verließ Polarstern 
das Meereis und lief in der nahezu eisfreien Laptevsee westwärts in Richtung 
Vilkitskystraße. Dort wurde auf einer kleinen Insel ein vor einem Jahr 
angelegtes Meßfeld auf dem Festeis mit einem Hubschrauber besucht, um 
Informationen über Schmelz- und Gefrierprozesse zu gewinnen.

Der Weg durch die Vilkitskystraße, die Karasee und die Barentssee bis nach 
Murmansk war in diesem Jahr eisfrei und erlaubte wiederum einen Zeitgewinn, der 
einer wünschenswerten Verlängerung der Umrüstzedit es Schiffes in Bremerhaven 
zugute kam. Während eines kurzen Hafenaufenthaltes in Murmansk am 15./16. 
September verließen ein finnischer und sechs russische Wissenschaftler sowie der 
Eislotse das Schiff, das dann die Reise durch die Barentssee, die Norwegische 
See und die Nordsee heimwärts fortsetzte. Am 23. September lief Polarstern in 
Bremerhaven ein, wo sich im Laufe des Tages alle Wissenschaftler und Techniker 
ausschifften.



2. Summary and Itinerary

The multinational expedition ARCTIC '96 was carried out jointly by two ships, 
the German RV Polarstern and the Swedish RV ODEN. The research programme was 
developed by scientists from British, Canadian, Finish, German, Irish, 
Norwegian, Russian, Swedish and US American research institutions and 
universities. The multidisciplinary field programme was shared between the two 
ships on the basis of their specific technical capabilities. Thus, the work on 
the ODEN concentrated on geology, geophysics, air chemistry and sea ice remote 
sensing while the investigations on Polarstern were devoted to physical, 
chemical and biological oceanography, sea ice physics and biology as well as to 
the atmospheric boundary layer.

The physical programme on Polarstern was primarily designed to foster the Arctic 
Climate System Study (ACSYS) in the framework of the World Climate Research 
Programme (WCRP). Investigations during the recent years have provided 
substantial evidence that the Arctic Ocean and the adjacent shelf seas play a 
significant role in the thermohaline oceanic circulation and may therefore have 
a distinct influence on global climate. Consequently the main ACSYS goals are 
concerned with studies of the governing oceanic, atmospheric and hydrological 
processes in the entire Arctic region. Among those the description and modeling 
of the circulation, the water mass modification as well as the energy and matter 
transports in the Arctic Ocean are of high importance. On Polarstern 
measurements were conducted in this respect to

• specify hydrographic structures on the transect from Franz Joseph Land to 
  Severnaya Zemlya which will enable one to determine the water mass exchanges 
  between the shelf seas and the deep Arctic basins via the St. Anna and Voronin 
  Troughs,
• describe the circulation within the Nansen and Amundsen Basins as well as 
  to detect the topographic influence of the Lomonosov Ridge on the water mass 
  spreading across the basins,
• observe the time variations of the currents, the heat and the salt 
  transports along the continental slope and across the ridge,
• determine the atmospheric forcing On sea ice under different large scale 
  atmospheric flow conditions
• provide information on the thickness and surface morphology of sea ice in 
  various regions of the Arctic Ocean.

In addition to these ACSYS related topics measurements were carried out to study 
the sea ice biota, to describe the lateral distribution of phytoplankton and 
zooplankton and to identify the governing chemical processes in the water 
columns of different circulation branches. For these purposes measurements were 
made from the ship, with the aid of helicopters and from ice floes with a series 
of Instruments some of which have been newly developed. The physical and 
chemical data will, among others, serve to test and to improve present and 
future ocean, sea ice and climate models.

On Polarstern 43 Crew, 1 Russian ice pilot and 53 scientists and technicians 
from Germany (29), Sweden (7), Russia (6), USA (5), Canada (3), Finland (1), 
Ireland (1) and the United Kingdom (1) participated in the cruise. The 
measurements were carried out by multinational subgroups and the processing and 
scientific analysis of the data will also be done jointly by members of the 
participating institutions in the near future. The cooperation between the ODEN 
and the Polarstern during the expedition was mainly restricted to logistic 
matters. During two rendezvous at sea personnel, scientific gear and fuel were 
exchanged. Daily radio conferences were held for mutual Information on the 
current activities on both ships as well as on weather and ice conditions.

Polarstern departed from Bremerhaven on Friday, 12 July 1996 and she arrived 
after a smooth voyage on 19 July in Murmansk, Russia. Here 7 Russian and 1 
Finish scientists and 2 ice pilots embarked. Local representatives visited the 
ship during the afternoon of the Same day in the framework of a cocktail 
reception. Polarstern left port again on 20 July for the Kara Sea. When she had 
passed the Russian territorial waters she met a small tanker at sea to top up 
her fuel tanks in final preparation for the long voyage into the ice covered 
Arctic Ocean. The pack ice was encountered on 23 July at about 78°N in the 
Barents Sea half a day before the first rendezvous with the Swedish partnership 
ODEN. During this meeting 1 scientist and 1 ice pilot as well as some 
Instruments were transferred from Polarstern to ODEN and the Russian observer 
who was in charge for both ships moved to Polarstern to stay there for the next 
3 weeks.

The two ships separated on 24 July when Polarstern commenced the first 
hydrographic section across the St. Anna and Voronin Troughs as shown in Fig. 1 
and ODEN continued her northward course towards the Lomonosov Ridge. 
Hydrographic vertical profiles were measured with the aid of a CTD 
(conductivity, temperature, depth) sonde, rosette water samplers and 
occasionally an acoustic doppler current profiler (ADCP). The dense hydrographic 
network on all transects included at various stations also biological net hauls, 
measurements on ice floes and atmospheric turbulence investigations. For the 
latter a new vertically pointing mast with acoustic anemometers and thermometers 
was attached to the bow crane. Furthermore, a sophisticated device, the HELIPOD 
which was suspended at a 15 m long cable below a helicopter to measure turbulent 
fluxes along specific flight tracks at various heights.


Figure 1:  Cruise track of RV Polarstern during ARCTIC '96


On the way from Franz Joseph Land to Severnaya Zemlya the ship's motion was 
increasingly slowed down towards the east by highly concentrated and partly 
compressed sea ice. Finally Polarstern had to make a 30 nm side step to the 
north to be able to finalize the full section across both troughs on 1 August 
1996. On the eastern side of the transect the first meteorological automatic 
surface buoy was deployed on an ice floe. At about 82°N / 90°E Polarstern set 
course first towards north to Cross the continental slope and afterwards to the 
northeast for a long transect from the Kara Sea via the Nansen Basin, the Mid 
Oceanic Ridge, the Amundsen Basin, the Lomonosov Ridge into the Makarov Basin. 
The farther the ship got north the more favourable the ice conditions became. 
Leads grew wider and longer so that the ship could sometimes speed up to 12 
knots between stations. Since our planning was based on a mean speed of 3 kn 
within the ice time was gained for extended measurements along the route. To our 
surprise the Mid Oceanic Ridge (Gakkel Ridge) was merely obvious in the echo 
soundings so that no orographic boundary separates the Nansen and the Amundsen 
Basins at least on Polarstern's track line. Because of the relatively fast 
motion of the ship we approached the ODEN at the envisaged drilling site 3 days 
earlier than anticipated. Thus, the second rendezvous was arranged for the 11/12 
August 1996 over the Lomonosov Ridge. The main purpose of the meeting was to 
transfer ship's diese1 from the ODEN to the Polarstern and helicopter fuel into 
the reverse direction. Furthermore, the Russian observer returned to the ODEN. 
During a planning meeting of the chief scientists and the masters of both ships 
it was concluded that according to this year's ice conditions Polarstern would 
try to retrieve three ocean moorings at the continental slope of the Laptev Sea 
without the assistance of ODEN. On the basis of this decision ODEN modified her 
plans for the research work and for her way home. Polarstern continued the 
interrupted hydrographic section and reached the Makarov Basin on 15 August 
1996.

On the transit voyage to the next section across the Lomonosov Ridge the ship 
hit again many leads so that a significant amount of time could be saved for 
more measurements along the transect. An array of automatic meteorological and 
oceanographic surface buoys was deployed in the central Amundsen Basin. The 
letter provide atmospheric surface data and conduct also measurements of the 
temperature, salinity and currents in the upper 200 m of the water column.

During the transit to the most northerly mooring location the ice concentration 
increased considerably and Polarstern's speed was remarkably reduced. In spite 
of the dense ice cover the mooring could be recovered rather rapidly On 23 
August due to its accurate positioning System and to the careful maneuvering of 
the ship by her experienced personnel. The ship steamed then first 30 nm to the 
west to commence the southern zonal section across the Lomonosov Ridge. Due to 
compressed ice this task was rather cumbersome and finally two of the planned 
stations had to be skipped since helicopter reconnaissance flights made it 
obvious that the entire Passage to the second mooring had to be made through a 
compact sea ice cover. Polarstern arrived at the second mooring position on 29 
August. Fortunately there were some small patches of Open water at and near the 
location of the mooring so that the retrieval could be managed again within a 
few hours time. During the completion of the meridional section across the 
mooring Polarstern had to overcome the severest ice conditions of the entire 
expedition and she was once trapped for 14 hours by compressed ice floes.

During the transit to the third mooring cloud free satellite images of our wider 
area could be received On the ship showing long and broad leads pointing from 
the actual ship's position towards the location of the last mooring. These 
indications were confirmed by helicopter flights so that the 180 nm distance 
could be traversed in less than two days. Since a low ice concentration 
prevailed over the mooring a fast and easy recovery was possible and again more 
time could be made available for observations and samplings. This opportunity 
was used on the one hand to collect additional biological material and On the 
other hand to extend the atmospheric boundary layer investigations in the 
marginal ice Zone. When all measurements were completed the observational 
Programme on Polarstern was terminated on 5 September 1996.

At midnight of the Same day the ice edge was crossed and the homeward journey 
started through almost ice free waters of the Laptev Sea. The last scientific 
mission was carried out by a helicopter to revisit an experimental site on the 
fast ice of a Because of generally Stern winds in the Kara and Barents Seas the 
ship could move with reduced power to the port of Murmansk to save fuel and to 
avoid refueling prior to the arrival in Bremerhaven. During the port call in 
Murmansk on 15/16 September 6 Russia scientists one Finish colleague as well 
as the Russian ice pilot disembarked. Polarstern arrived at her home port 
Bremerhaven on 23 September to terminate her ARCTIC '96 cruise.




3.  Research Programmes

3.1  Physical and Chemical Oceanography
     (AWI, lfMH, lfMK, IUH, AARI, GU, BIO, UW, ESR, SIO, LDEO, UCD)*

3.1.1  Introduction

Waters modified in the Arctic Ocean influence the thermohaline circulation of 
the Atlantic Ocean and thereby also of the global ocean. As the modification of 
waters in the Arctic is largely controlled by shelf processes, characteristics 
of the inflow from the shelves are of similar importance as of the flow of 
different branches along the continental slope and along oceanic ridges. Our 
measurements are thus carried out to better comprehend the circulation Pattern, 
flow rates and water mass modification in the Eurasian Part of the Arctic Ocean.

Atlantic water enters the Arctic Ocean through Fram Strait and through the 
Barents and Kara Seas. Both branches merge over the continental slope in the 
eastern Nansen Basin. The Atlantic water passing through the Barents and Kara 
Seas is considerably modified by air-sea interaction processes and by inflow of 
river water. Consequently this water is colder and less saline when it meets the 
Fram Strait Branch of Atlantic water in the Nansen Basin so that a distinct 
front separates these two water masses. Various substances originating from the 
atmosphere and from river input or resulting from shelf specific biological 
processes enable us to trace the flow path of the Barents Sea Branch Water 
throughout the Arctic Ocean and to determine its flow rate.

From previous cruises it was concluded that both of the above mentioned branches 
partly recirculate in the Nansen and Amundsen Basins and partly enter the 
Canadian Basin across the southern Lomonosov Ridge. Deep waters may also be 
exchanged between the Amundsen and Makarov Basin intermittently through trenches 
of the Lomonosov Ridge.

Earlier measurements have already shown highly structured vertical layers which 
are frequently characterized by inversions of the temperature and the salinity. 
Some of these layers can be identified over large (basin wide) distances. The 
inversions are believed to result from interleaving of different water masses at 
frontal zones. Finally double-diffusion processes may to a certain extent alter 
the vertical temperature and salinity distribution of the layered structures.

The specific oceanographic goals during this cruise were to:

• accomplish a hydrographic vertical section across the St. Anna and the Voronin 
  Through to examine the water mass characteristics of the inflow from the 
  Barents and Kara Seas into the Nansen Basin
• qualitatively and quantitatively describe the circulation in the Nansen, 
  Amundsen and Makarov Basins as well as the exchanges of intermediate and deep 
  waters between the different basins
• investigate the fate of shelf water within the deep basins
• determine the gas exchange (oxygen and carbon dioxide) between the partly ice 
  covered Arctic Ocean and the atmosphere
• study processes influencing the heat, salt and momentum fluxes in the surface 
  layer and across the halocline
• determine the optical properties of the Arctic sea water in summer conditions
• See Chapter 5 for explanation of contributing institutions

All observations were made on transects (Fig. 2) along the Kara Sea shelf break 
crossing the St. Anna and Voronin Troughs, across the Nansen and Amundsen Basins 
into the Makarov Basin, across the Lomonosov Ridge and across the continental 
slope of Laptev Sea and the East Siberian Sea. The station spacing ranged 
between 5 km and 30 km. CTD/rosette casts were made on all stations.


3.7.2  Methods and First Result of Temperature, Salinity and Oxygen Measurements

Vertical profiles of temperature and conductivity were measured with a modified 
Neil Brown Mark 111 b CTD System combined with a 36-bottle rosette sampler, both 
from the Scripps Institution of Oceanography. The CTD was also equipped with two 
platinum resistance thermometers to control the stability of its temperature 
Sensor. The temperature and pressure gauges of the CTD were calibrated before 
and after the cruise. Salinity values derived from the CTD measurements were 
calibrated with the aid of water samples which were analyzed on board with a 
Guildline Autosal 8400 B salinometer.


Figure 2: Dots mark all hydrographic stations and the M symbols indicate the 
          positions of the three moorings


The sampling and measurement of dissolved oxygen were carried out according to 
the WOCE protocol. Analyses of oxygen were performed by a modified Winkler 
titration procedure. The titrator has a precision of about ± 0.05 µM/kg under 
laboratory conditions but due to sampling errors at sea the relative accuracy 
lies at ± 0.2 µM/kg. The absolute accuracy which accounts e.g. for the 
systematic error caused by the natural iodate in seawater is estimated to range 
at 1 to 2 M/kg. Examples of the distributions of salinity and dissolved oxygen 
across the Nansen and Amundsen Basins and the Lomonosov Ridge are shown in Fig. 
3 and 4, respectively.


Figure 3: Salinity distribution On the section from the continental slope of the 
          Kara Sea to the Makarov Basin
Figure 4: Same section as Fig. 3 for dissolved oxygen


3.1.3  Nutrients

In the Arctic Ocean nutrient concentrations provide a valuable tool to trace 
water masses and to detect transport and mixing mechanisms. By this means 
Pacific water with high silicate concentration which flows through Bering Strait 
can be traced via the Chukchi-East Siberian Sea to Fram Strait and the Greenland 
Sea. Silicate concentrations in deeper water were used to determine large scale 
circulation Patterns and they have provided convincing evidence that the shelf 
slope plume contributes to the formation of deep water.

Silicate, phosphate and total nitrate (nitrite plus nitrate), were analyzed from 
all sampling depths at all stations. The samples were drawn in 30 ml plastic 
bottles, refrigerated and analyzed normally within 36 hours alter collection. 
Analyses were carried out with an AutoAnalyzer by standard procedures.


3.1.4  Carbonate System

The carbonate system was determined by analyzing the rosette water samples for 
Total Dissolved Inorganic Carbon (CT), Total Alkalinity (AT) and pH. They are 
defined as

CT = [CO2] + [H2CO3] + [HCO3] + [CO32-]
AT = [HCO3-] + 2[CO32-] + [B(OH)4-]
pH = -log [H+]

Hence, any of the carbonate species can be calculated from two of these 
parameters. CT was determined by the standard coulometric technique, AT by 
potentiometric titration and pH by a multi-wavelength spectrophotometric 
technique. Both AT and CT are largely correlated with salinity but some 
biogeochemical processes will shift their concentration. AT is mainly affected 
by formation and dissolution of metal carbonates, while CT also is affected by 
air-sea exchange of CO2 and by photosynthesis and microbial decay of organic 
matter. Like CT, pH is affected by all of these processes. In the Arctic Ocean 
AT and CT are useful tracers of runoff, as this contains high concentration of 
HCO3- as a combined result of decay of organic matter and dissolution of metal 
carbonates.

The motivation for determining the carbonate system during Arctic '96 was; (i) 
to study shelf - deep basin interaction by using signals caused by biogenic 
processes on the shelves, (ii) to investigate how the runoff is spread out into 
the central Arctic Ocean from the Kara and Laptev Seas and (iii) to estimate the 
air -sea exchange of CO2 in ice covered regions.

Samples from about 75% of the stations occupied during the cruise were analyzed 
for all three parameters. An example of the runoff signal being stronger in the 
top 100 m over the Lomonosov Ridge (Stn 70) compared to the Nansen Basin (Stn 
36) is shown in Fig. 5.


Figure 5: Depth profiles of total dissolved inorganic carbon, normalized to a 
          salinity of 35, for stations 36 (Nansen Basin) and 70 (Lomonosov Ridge).


3.1.5  Chlorofluorocarbons

Chlorofluorocarbons measured during this expedition, CFC-11, CFC-12, CFC-113 and 
carbon tetrachloride (CCL4) are anthropogenic compounds the concentration of 
which has been increasing in the atmosphere, and hence in ocean surface waters, 
beginning with CCL4 early in this century, CFC-11 and CFC-12 in mid-century and 
CFC-113 in recent decades. CFC-11 and CFC-12 are believed to be highly stable in 
the marine environment. CCL4 is thought to be stable in cold waters below 10Â° 
but does hydrolyze in warm waters. In the ocean these compounds help to estimate 
exchange rates of water and to trace water masses by distinguishing "older" 
water from "younger" water.

CFC measurements were made in samples from almost all stations shown in Figure 2 
and from all depths. Samples were drawn in 100 ml syringes and analyzed within 
24 hours after sampling. Analyses were done by members of the Institut für 
Meereskunde, Kiel (IfMK) and of the Bedford Institute of Oceanography (BIO). 
Both groups used purge-and-trap Systems, one measuring CFC-11 and CFC-12 (IfMK) 
and the other (BIO) measuring all four compounds. More than 600 of the samples 
were analyzed. Intercalibration between the two systems resulted in sufficient 
agreement for CFC-12, while a ten per cent difference in CFC-11 values needs 
still to be explained.


3.1.6  Tritium. Helium and 180

Transient tracers such as Tritium/3He and stable isotopes like 18O provide 
information on circulation and residence times of water masses. Tritium decays 
with a half life time of 12.43 years into stable 3He. Thus, the 
ratioTritiuml/3He can be used to determine the last time at which a water 
molecule has been in contact with the atmosphere. The stable isotope 18O, in 
combination with salinity, is well suited to separate river water and sea ice 
meltwater fractions within the Arctic Ocean. High latitude river runoff is 
marked by low 18O/16O values, whereas in sea ice this ratio is primarily 
determined by the generally higher value of the freezing sea water.

Members of the Lamont-Doherty Earth Observatory of the Columbia University 
(LDEO) and of the Institut für Umweltphysik der Universität Heidelberg (IUP) 
have collected over 800 Tritium, Helium an 18O samples. The water was stored in 
40 ml pinched-off copper tubes, 1 liter glass bottles and 50 ml glass bottles. 
The samples will be analyzed at LDEO and IUP both using fully automated isotope 
mass spectrometers. Precision of ±0.2% for the 3He/4He ratio and of ±2% for 
Tritium are routinely achieved.

The stable isotope ratio of 18O/16O will be obtained to an accuracy of ±0.02 to 
0.03 ‰.


3.1.7  Inorganic Minor Element Tracers

At all stations samples were taken for the Oregon State University to determine 
inorganic minor element tracers such as Rb, Cs, Ba, Sr, Li, B, F, I, Cd and 
isotopes of Sr and Li. Results of these analyses will be used to trace river 
waters along their paths in the Arctic Ocean.


3.1.8  Volatile Halogenated Organic Compounds


Volatile halogenated compounds are ubiquitous trace constituents of the oceans 
and the atmosphere. Among others halogens have the ability to affect the 
atmospheric ozone budget.

Bromine is found most often in compounds originating from the ocean although the 
bromide concentration is much lower than that of chloride in sea water. Besides 
of brominated substances, chlorinated and iodinated ones are also present in the 
oceans. But no reliable estimates are actually available on the strength of the 
oceanic source. Organo-chlorine compounds in the marine environment are 
primarily attributed to human activities (pesticides, anti-freezing agents 
etc.), but in addition both, macroalgae and microalgae produce chlorinated 
compounds such as chloroform, trichlorethylene and perchlorethylene which are 
emitted from the ocean into the atmosphere, where they participate in various 
chemical reactions. lodinated compounds have relatively short lifetimes in the 
troposphere, whereas chlorinated and brominated ones may even reach the 
stratosphere. During this cruise the distribution of halocarbons in the water 
column, the formation of halocarbons by pelagic and ice-living organisms and the 
flux of halocarbons across the air-sea interface were investigated.

For these purposes sea water samples were collected from the rosette sampler on 
most of the ship's transects. Water was drawn in 100 ml glass syringes. The 
compounds were pre-concentrated with a purge and trap system prior to analysis 
with capillary gas chromatography. Due to the analysis time of 28 minutes 
samples could be taken from only 12 different depths, To avoid contamination of 
the purge and trap system with micro-organisms, all samples were filtered 
through a GFC filter prior to analysis. The formation of naturally produced 
halocarbons by different sized micro-organisms, were studied. Surface water was 
filtered through a unit with 5 different sized filters: 1000, 150, 12, 2 an 0.4 
mm. Each fraction contained 250 ml of water. After the filtration of 
approximately 25 l of water, during a period of 4 hours, the water from the 
different compartments was put in 60 ml glass bottles. Care was taken to avoid 
any headspace volume in order to minimize losses of the compounds to air. The 
glass bottles were put into a refrigerator, with a mean temperature of 0°C and 
a light intensity of approximately 20 - 40 mmol photons m-2 s-1. The formation 
of halocarbons was measured after 6 to 60 hours after sampling. Prior to 
injection, the water was filtered through a GFC filter, and the chlorophyll 
content was measured by standard procedures.

The lower most 20 cm of ice cores were collected at 16 stations in order to 
determine the formation of halocarbons by ice-living organisms. 10 cm pieces of 
ice were put into air tight glass jars, which were also put into the 
refrigerator. Air samples were collected at different time Intervals. Fluxes of 
the compounds across the air-sea interface were derived with the additional aid 
of the air samples. We found the mean surface concentrations of the biogenic 
halocarbons to be relatively low during the entire cruise. Bromoform is 
generally produced by macroalgae in rather high quantities and to a lesser 
extent by pelagic organisms. Since this substance has a relatively long half-
life time in sea water, it can be traced throughout the entire water mass. But 
during the cruise the mean surface water concentration was less than 1 ng/l, 
which is rather low in comparison to 4 ng/l measured in the Arctic Ocean 1991. 
And at depths below the productive Zone the concentration were frequently below 
the detection limit (100 pg/l).

In contrast iodinated substances were found more frequently this year than in 
1991. An example of the distribution pattern of iodinated compounds is shown in 
Fig. 6.


Figure 6:  The distribution of Methyliodide across the St. Anna and Voronin 
Troughs


3.1.9  Dissolved Organic Matter (DOM)

The DOM in marine ecosystems helps to determine the global carbon and nitrogen 
cycles. DOM in the world oceans has the Same order of magnitude as carbon 
dioxide in the global atmosphere. Of major importance are processes which 
produce substances which are retained from the carbon-cycle. Humification, e.g. 
leads to substances which are mostly resistant to microbial attacks. A 
considerable amount of DOM is transported into the Arctic Ocean through the 
Siberian rivers Lena, Yenissey and Ob. From our samples we intend to investigate 
the modification of the molecular structures of DOM during its way through the 
Arctic Ocean.

Water samples were filtered through precombusted glass fiber filters (Whatman 
GF/F), filled into precombusted ampoules and stored in a frozen state. Upon 
return to Bremerhaven the samples will be analyzed for:

• dissolved organic carbon (DOC) which will be determined by HTCO (high 
  temperature catalytic oxidation).
• Humic Substances (HS). Here preparatory work had to be done already On board. 
  Before extraction of the humic substances, seawater samples were filtered 
  through precombusted glass fiber filters (Whatman GFIC). 20 l were acidified to 
  pH2 with hydrochloric acid (Merck suprapur). 20 l of the acidified filtrates 
  were passed through the XAD-columns within 24 h. Thereafter, the columns were 
  rinsed with 200 ml of 0.01 N HCl to remove salt. The resins were stored at -30°
  C The organic matter of several resins was eluted for further experiments on the 
  bioavailability. The fraction eluted with base is a so called hydrophobic acid 
  (HbA), and the fraction eluted thereafter with methanol is considered as 
  hydrophobic neutral (HbN).
• Amino acids in the water samples and in the XAD-fractions with the aid of HPLC 
  after precolumn derivatisation with o-pthalaldehyde (OPA) and N-lsobuyryl-
  Lcystein (IBLC). This method permits the separation of all important D- and L-
  amino acids. Free amino acids (FAA) will be measured directly, combined amino 
  acids will be hydrolyzed with 6 N hydrochloric acid.

3-D-fluorescense spectra of the DOM were recorded for further characterization. 
Filtered water samples were measured in 1 cm cuvettes with a Perkin Eimer LS 50 
fluorometer. The excitation range was 200 - 350 nm, the emission range was 230 - 
450 nm.

Experiments on the bioavailability of HS were conducted already on board. 
Natural bacterial population of the corresponding water sample were extracted 
gently by gravity filtration (0,2 µ). The bacteria were then added to artificial 
seawater supplemented with HS as the only carbon source. To assess the limiting 
parameters experiments were conducted with different nutrient and HS 
concentrations. Incubations were done near in situ temperatures (0- -1°C). 
During two weeks sub samples were taken in certain time Intervals for later 
analysis of DOC, bacterial numbers and bacterial growth rate.


3.1.10  Physical and Chemical Speciation of Plutonium (and Americium) in the 
        Arctic Water Column

The main objective of the Plutonium and Americium analyses is to examine the 
kinetics of transuranium nuclides reactivity within the Arctic water column and 
how they are influenced by the chemical speciation and association with 
suspended particulate and colloidal matter. The overall goal is to achieve an 
understanding of the basic processes governing the horizontal and vertical 
dispersion of Plutonium and Americium under extreme environmental conditions.

Particular emphasis was put on the determination of high resolution vertical 
profiles of Plutonium and Americium in the shelf seas and the central Arctic 
Ocean, the partition of these radionuclides between filtered and suspended 
particulate phases, the fraction in colloidal form and the size and composition 
of the latter. The aim was to obtain a reliable database on radionuclide 
concentrations in the various water masses, as well as experimental values for 
the parameters controlling the transfer rate between the water column and the 
sediment compartments. The values will ultimately be used to refine and validate 
an existing compartment model covering the Arctic seas and to predict individual 
and collective doses from potential discharges of radioactivity to these seas. 
The latter is the goal of a multinational collaboration (ARMARA) involving 
thirteen European institutions.

A total of 75 sea water samples were collected from different depths at 41 
stations along the ship's transects. Near-surface sea water samples were taken 
from approx. 10 m below the surface using the membrane pump located at the 
ship's bow, while deep waters were retrieved using 10 l Niskin bottles mounted 
in a rosette sampler. In all cases, samples were promptly filtered in situ 
through membrane (screen) filters (0.45 µm) and the filters were retained for 
analysis of radionuclide content in the suspended particulate fraction. The 
filtered fractions were then pre-concentrated onboard either for subsequent 
total Plutonium (and Americium) analysis by CO-precipitation with ferrix 
hydroxide according to the method of Wong et al. or for Plutonium oxidation 
state distribution analysis using a scaled-up version of the rare-earth fluoride 
CO-precipitation technique of Lovett and Nelson.

Along the hydrographic section between Franz-Josef-Land and Severnaya Zemlya, a 
total of 32 samples were collected at 14 stations. Sampling concentrated along 
the eastern flanks of the St. Anna and Voronin Troughs, where water mass outflow 
from the shelves was anticipated. The analyses included the determination of 
total Plutonium concentrations, the examination of the oxidation state 
distribution of Plutonium in filtered sea water at two vertical profiles in the 
St. Anna Trough and the size fractionation of particle-bound Plutonium in 
surface waters, including the colloidal component.

The oxidation state distribution of Plutonium in filtered water was examined at 
two high-resolution vertical profiles taken during the second hydrographic 
section between the Nansen and Makarov Basins. The samples were collected from 
two stations located at the deepest parts of the Nansen and Amundsen Basins. 
Each profile consisted of samples retrieved from eight depths ranging from 10 to 
4500 m. On the sections across the Lomonosov Ridge and across the continental 
slope in the Laptev Sea region, a total of 28 surface and sub-surface samples 
were taken for total Plutonium and Americium concentrations. Two large volume 
samples were also collected in order to examine the size fractionation of the 
colloidal component of these radionuclides by tangential-flow ultra filtration.

A considerable Part of the analysis was conducted already on board of the ship 
and the final analysis of the samples will be carried out at the Department of 
Experimental Physics, University College Dublin. It is estimated that this will 
involve a total about 250 separate radiochemical determinations, including 
reagent blanks and international inter-comparisons. Plutonium concentrations in 
the speciation samples will be determined by high-resolution mass spectrometry, 
while total Plutonium and Americium samples will be determined using a 
combination of high-resolution alpha spectrometry and high-resolution mass 
spectrometry.


3.1.11  Acoustic Doppler Current Profiler (ADCP)

CTD measurements combined with an ADCP were carried out to detect details of 
water motions associated with small scale temperatures and salinity structures. 
ADCP/CTD observations were made on the zonal section across the Kara Sea across 
the continental slope in the Kara Sea sector and across the Lomonosov Ridge 
between the Amundsen and Makarov Basins.

Two ADCP, one measuring at 150 KHz and the other a 600 kHz, were applied. The 
first has a range of 250 m, the second a range of 60 m. In the interior of the 
water column, only relative motions (shears) associated with the interleaving 
structures can be detected. However, at almost all stations the instruments were 
run also on a bottom track mode to record motions at the shelf break and at the 
slopes of the Lomonosov Ridge. During the cruise 54 casts with the SeaBird CTD 
and a RDADCP were accomplished. The winch speed was about 40 cm/s in order to 
get detailed measurements of the fine structure and to achieve a low noise level 
for the ADCP.


3.1.12  Shipborne ADCP

Vertical profiles of the ocean currents in the topmost 250-350 m of the water 
column were obtained at most of the hydrographic stations.

The measurements consist of time series which are made up by vertical profiles 
of one-minute vector-average current values. Typically 2-4 hours long, records 
were obtained. One observational period exceeded 15 hours in time. Some results 
from the 15-hour record are presented in Fig. 7. These measurements will 
supplement other recent observations of the vertical shear in the upper few 
hundred meters of the Arctic Ocean. Similar data were obtained from Polarstern 
in the Eurasian Basin in 1993 and 1995, and data have been acquired in the 
Canadian Basin during summer 1996 by a US Navy submarine. Vertical shear can be 
used in conjunction with CTD measurements to estimate vertical mixing Parameters 
and to derive vertical fluxes of heat and salt in the upper ocean.


Figure 7: An example of shipborne Doppler current measurements below the mixed 
          layer


3.1.13  Optics

The optical characteristics of the sea water affect the production of 
phytoplankton and the absorption of solar radiation in the upper layers of the 
water column. Ocean colour is furthermore utilized for optical remote sensing in 
order to determine the surface chlorophyll. Therefore, measurements have been 
conducted

• to describe optical properties in the Arctic Ocean surface water and
• to explain the observed distributions of chlorophyll, oxygen and phosphate in 
  Arctic surface waters.

Optical measurements in the upper 60 m of the water column were performed at 44 
CTD stations where chlorophyll was also analyzed.

The following devices were applied:

• Quanta meters for underwater irradiance measurements in the visible wavelength 
  interval of 350-700 nm. One plane quanta meter for relative irradiance. One 
  LiCor spherical quanta meter for the scalar irradiance of the total flux of 
  photons to a sphere (PAR-Photosynthetic Available Radiation). Both were lowered 
  on the Same frame equipped with a pressure Sensor.
• Secchi disc of 50 cm diameter for Secchi depth readings of the total 
  backscattered light.
• Colour Index meter to measure the radiance of the backscattered light dose to 
  the surface for three different wavelengths (450, 510, 550 nm).
• Quantum Sensor to measure Photosynthetic Photon Flux Density (PPFD) in the 
  atmosphere as reference during the underwater measurements.

The estimate of the Secchi depth by eye was made at about 6 m above the sea 
surface. Quanta measurements were mostly made during overcast conditions. The 
quanta meter readings will be analyzed together with the readings of the deck 
quanta. The incoming daylight during station time varied between 942 and 51 µmol 
m-2s-1.

As a result of absorption and scattering of the solar flux the irradiance 
diminishes in an approximately exponential manner. The exponential decrease of 
quanta at two stations is shown in Fig. 8. Station 29 has more chlorophyll in 
the upper oceanic layer than station 80, Secchi depths readings in Arctic waters 
are highly dependent on the particle content of the water and less on dissolved 
(yellow) substances. The particles could be of both organic and inorganic 
origin. The Secchi depth (ZS) gives a rather good approximation of the light 
attenuation.


Figure 8: Vertical profiles of the photosynthetic available radiation (PAR)


The Colour Index meter is designed to measure the underwater light regime 
independent of clouds, sun elevation, waves and ship shading. It contains two 
photocells equipped with interference filters of 450 nm, 520 nm and 550 nm that 
face downward to record nadir radiances. The Colour Index, defined as the 
radiance of blue (450 nm)/radiance of green (520 nm) yields Information about 
the quanta distribution in the whole euphotic zone. Thus, from the colour index 
it is possible to calculate how deep light penetrates. The averaged colour index 
for all 44 stations is 2.14 at 1.5 m depth. The depth of the euphotic Zone 
calculated from the colour index for all 44 stations is 60 m.


3.1.14  Ocean Moorings

Three highly instrumented moorings had been deployed one year ago at the 
continental slope of the Amundsen and Makarov Basins and at the Eurasian side of 
the Lomonosov Ridge (Fig. 2) at depths around 1700 m.

Each mooring was equipped with current meters at 100, 270, 700, 1100 meters 
depth and at 20 meters above the bottom. At the two uppermost and at the deepest 
levels Sea Bird SBE-16 (SeaCats) instruments were also installed to measure the 
conductivity and temperature. The depths were chosen to monitor the halocline 
(100 m), the warm Atlantic core water (270 m), the Barents Sea inflow (700 m and 
1100 m) and to detect currents of dense bottom water originating from the 
shelves. Two of the moorings carried upward looking Sonars to determine the 
draft of sea ice. The mooring at the Lomonosov Ridge was furthermore equipped 
with two sediment traps at 150 m depths and at 150 m above the bottom.

The current meters and the SeaCats of all moorings and one upward looking Sonar 
have operated continuously. Each sediment trap has collected twelve monthly 
samples. The recovered instruments will be calibrated and the data will be 
reduced by the owners of the various instruments. Preliminary current meter data 
(converted onboard) are portrayed in Fig.9.


Figure 9: 3 days time series of current vectors at the mooring LOMO-2



3.2  Oceanographic/Meteorological Buoys
     (AWI, AARI)

Eight drifting surface buoys were deployed at positions indicated in Fig. 10. 
The positions of the drifting buoys are determined by the Global Positioning 
System (GPS). All buoys, except one, are equipped with sensors for air 
temperature and air pressure. Two buoys are additionally equipped with ice 
thickness sensors, two others with anemometers at 2 m height. Five buoys have 
been deployed in an array of 160 km diameter. The central two buoys carry a 200 
m long subsurface chain with sensors for water temperature, conductivity, 
pressure and current velocity. These two buoys were deployed 8 km apart on one 
large ice floe in order to record small scale coherent oceanic features. All 
data are transferred in real time to the Global Telecommunication System (GTS) 
and are thus available for weather forecast purposes.


Figure 10: Positions of automatic meteorological surface buoys (triangles) and 
           two oceanographic Systems (dot)



3.3  The Atmospheric Boundary Layer
     (AWI, IMKH, AERODATA, AARI, OAP)

Fluctuations of the wind velocity, the air temperature and moisture were 
measured to document the structure of turbulence in the polar atmosphere and to 
improve the parameterization of the subgridscale processes in atmospheric models 
of different spatial resolution. Measurements were carried out with the aid of a 
new sophisticated instrument, the HELIPOD, which is mounted on a 15 m long cable 
below the cabin of a helicopter and with a turbulence measuring system (TMS) 
which is installed at a vertical mast at the ship's bow crane. The TMS records 
turbulent fluxes of heat and momentum in 5 different levels between 3 m and 20 m 
height above the sea surface with sonic anemometers/thermometers. And humidity 
fluctuations are detected by a Lyman alpha Sensor at 3 m height. In addition the 
absolute humidity is measured by a dew point mirror and the vertical profiles of 
air temperature are obtained from PT-100 temperature sensors also at 5 levels.

The HELIPOD is able to measure wind vector, air temperature and moisture 
fluctuations with a time resolution of 100 Hz. Since the motions of the sonde 
are recorded simultaneously by special devices accurate values of the turbulent 
quantities can be determined. The system is designed, to work autonomously. To 
correct for any time drift of the fast sensors highly stable slow sensors are 
measuring temperature and relative humidity in parallel.

During Arctic '96 the TMS could be operated at 35 ship stations On 24 days. The 
minimum observational time lasted about 2.5 hours in order to achieve a 
satisfactory statistical accuracy. 24 HELIPOD flights were carried out on 20 
days. Flight Patterns to determine vertical flux profiles and surface fluxes are 
portrayed in Fig. 11. Surface fluxes have been mainly determined from flights in 
about 10 m height, for horizontal averages of more or less 30 km. The ice 
topography was measured simultaneously by a laser altimeter. Vertical profiles 
of the fluxes have been gained from box Patterns with side lengths of 8 km. The 
flight levels ranged from 7.5 m height to the top of the atmospheric boundary 
layer (approx. 100- 200 m).


Figure 11: Actual helicopter flight Pattern. Repeat tracks refer to different 
           flight levels


Turbulence measurements could be made on a large part of Polarstern's route 
(Fig. 12) so that the data are representative for summertime atmospheric 
conditions over the European Arctic Ocean.

Most of the observations were carried out when ice concentrations ranged above 
80%. Nevertheless inhomogeneous surface temperatures prevailed due to changes of 
ice thickness and to the effects of leads. Furthermore, the low level air flow 
was affected by the surface roughness caused by ice ridges and the edges of ice 
floes. Consequently, the surface layer was frequently well mixed while the upper 
part of the atmospheric boundary layer starting at 20 to 30 m height was stably 
stratified. In a few cases slightly stable or unstable density distributions 
were met also near the lower boundary of the atmosphere.


Figure 12: Positions where turbulence measurements were carried out with the 
           HELIPOD (triangles) and with the profile mast at the ship's bow crane 
           (dots)


Typical profiles of the turbulent fluxes are shown for two days (July 30 and 
August 20), when simultaneous measurements were carried out with the TMS and the 
HELIPOD (Fig. 13).


Figure 13: Vertical distributions of turbulent heat and momentum fluxes


The TMS values represent time averaged data over a period of about 45 minutes, 
the HELIPOD-data are horizontally averaged over some 30 km. The momentum fluxes 
of the two different systems fit rather well while the sensible heat fluxes seem 
to indicate some disagreement. But detailed inspections of the boundary 
conditions at the ship convinced us that local surface temperatures which differ 
distinctly from area averages have caused the observed differences. In 
particular on 20 August the ship's bow was located over a small lead which 
obviously created a local low level internal boundary layer. In several other 
cases out of a total of ten the results of both systems agreed closely.

Six experiments have been carried out to study internal boundary layers, which 
evolve during the Passage of the airflow from the ice edge towards Open water. 
For these purposes Polarstern was moved at a low speed of about 0.5 knots upwind 
across the lead towards the ice edge.

During the study on 8 August the water surface temperature was lower than the 
ice surface temperature so that a thin stable layer was present downstream over 
the water as illustrated in Fig. 14, which displays the momentum and sensible 
heat fluxes, the local drag coefficients (defined as the Square of local 
friction velocity divided by the local wind speed) and the local stability 
function 1/L (L is the Monin Obukhov stability length), as observed with the 
TMS.


Figure 14: Turbulent momentum (upper panel) and heat (lower panel) fluxes as 
           well as the drag coefficients (Cd) and the static stability function 
           (1/L). For details See text



3.4  Sea Ice Physics and Biology
     (AWI, IPÖ, AARI, GU, HUT, SPRI)

3.4.1 Visual Ice Observations

Visual ice observations were made from the ship's bridge every two hours when 
steaming through the ice. Concentrations of different ice types, ice thickness, 
Snow thickness, flow size, lead width, melt pond distribution and ridging 
characteristics were observed. In addition, concentration of the sediment laden 
ice and the amount of ice algae were estimated. The total ice concentration 
versus time is displayed on Fig. 15.


Figure 15:  Total ice concentration


After 15 August the formation of new thin ice (Fig. 16) began already.


Figure 16:  concentration of thin ice


The main feature on Figure 15 is the low concentration between 9 and 15 August 
during the northern most section of the cruise which is also obvious on the 
AVHRR image in Fig. 17. In this area second-year or multiyear ice was 
predominant (Fig. 18) and the Snow Cover amounted to 40 cm. According to the one 
year's drift of three ARGOS surface buoys (Fig. 19) the sea ice we met in the 
most northern area was formed in the Laptev Sea area at least one year ago. 
Summer surface melting conditions were observed only in the northern Kara Sea 
and in the southern Nansen Basin.



Figure 17: AVHRR image of the expedition area; cruise track: white line
Figure 18: Concentration of second and multiyear ice
Figure 19: Cruise track with indications of Julian days, three straight lines 
           are connecting the starting and actual positions of ARGOS-tracked buoys


3.4.2  On Ice Measurements

Measurements On the ice were performed On 37 floes. The geographical locations 
of these stations are indicated in Fig. 19. Ice station work comprised ice 
thickness measurements, ridge sail leveling and partly ice core drilling. The 
cruise track provided a unique opportunity to study different states of the ice 
cover upstream of the Transpolar Drift.


3.4.3  Laser Altimetry

The ice surface topography was frequently determined with a vertically downward 
looking laser altimeter mounted on a helicopter. The instrument was flown with a 
speed of 80 kn at a height of 30 m above the surface. The pixel spacing was 
about 0.02 m. Typical flight patterns were equilateral with a side length of 20 
nautical miles. 23 flights were performed with a total profile length of about 
2000 km. Additionally, some laser altimeter data were obtained during the 
HELIPOD flights. The data quality is expected to be high due to the absence of 
melt ponds and to the closed Snow cover.

The measurements will be primarily analyzed for pressure ridge statistics. The 
data will also serve as ground truth values for satellite radar altimeter 
measurements as well as for comparisons with the ice draft values derived from 
the upward looking Sonars (ULS) of the ocean moorings. A ridge height 
distribution for a flight across one mooring site is demonstrated on Fig. 20. 
The height distribution will be compared to the keel depth time series measured 
by the moored ULS.


Figure 20:  Ridge height distribution obtained from a laser altimeter flight


3.4.4  Ice and Snow Thickness

At 35 positions ice thickness was measured along linear profiles covering both 
level and deformed ice by means of an electromagnetic inductive (EM) technique. 
The EM Instrument (coil spacing 3.66 m, signal frequency 9.8 kHz) was mounted 
into a kajak which was pulled over the ice. On average, the thickness profiles 
extended over at least 1000 m with a point spacing of 5 m. In addition, Snow 
thickness and surface elevation (by means of leveling) were determined with a 
similar spacing along the first 200 m of the profiles and ice thickness was 
measured along these short sections by drilling at 20 m distance intervals to 
calibrate the EM soundings. The mean and modal total thickness for all stations 
as well as the standard deviation together with minimum and maximum values are 
shown in Fig. 21. These thicknesses compare rather well with the mean ice 
thickness determined from video images taken at the ship's bridge. From our 
observations six different ice regimes can be distinguished which are indicated 
in Table 1 and displayed in Fig. 22.


Figure 21: The thickness distribution along the cruise track
Figure 22: Standardized ice thickness spectra for 6 different regions of the 
           Arctic Ocean


All sampled floes were covered by old Snow and in the northerly regions also by 
fresh Snow on top. The Snow was thickest around ridges, thus smoothing their 
relief. Measured mean Snow thicknesses and their standard deviations are also 
listed in Table 1. The mean density of 31 samples of old Snow was 407 L73 kgIm3'


Table 1: Subdivision of the cruise track into six regions showing different ice 
         and Snow thickness characteristics (see also Figure 21)

___________________________________________________________________________

                                    Mean Total        Mean Snow  
 Region                   Stations  Thickness   Mode  Thickness  Std. dev.
 -----------------------  --------  ----------  ----  ---------  --------- 
 Kara Sea                 207 - 213  1.64±49%    0,8    0.08       0.10
 Nansen Basin             214 - 216  2.37±48%    1,6    0.07       0.09
 Transpolar Drift, west   216 - 221  2.50±38%    2      0.21       0.16
 Transpolar Drift, east   222 - 227  3.02±33%    2,4    0.26       0.15
 Transpolar Drift, south  229 - 243  2.13±31%    1,9    0.14       0.12
 Laptev Sea               246 - 249  1.29±58%    1,3    0.10       0.06
___________________________________________________________________________


3.4.5  Ridge Sail Profiles

The topography of the maximum height along pressure ridges was measured on most 
ice stations by a laser leveling device at 1 m intervals (Fig. 23). Generally 
data On ridges are obtained from transects across the ridges by aircraft laser 
altimetry and keel depths are measured by submarine Sonars so that the sail 
heights or keel depths are random samples of the actual values. With the aid of 
the sail profile statistics these data may be converted into more realistic 
ridge thickness values.

A total number of 25 ridges with a total length of 3.2 km was investigated. The 
maximum elevation found was 5.6 m and the mean elevation amounted to 3.1 m. 
Cross-sectional profiles were measured On 7 stations with special emphasis On 
the detection of the snow thickness (Fig. 24).


Figure 23: Topography of a pressure ridge along its axis
Figure 24: Topography of Snow covered pressure ridges across their axes



3.4.6  Trafficability

When Polarstern was steaming in the pack-ice ship performance data were analyzed 
together with ice thickness, lead width, floe size and ridging information. A 
considerable portion of the icegoing time was needed for ramming as can be 
concluded from Fig. 25. However, significant correlations were observed neither 
between the ridging intensity and the number of rammings per nautical mile nor 
between the ship performance and ice thickness. This is due to the fact that the 
ship proceeded along leads, whenever possible. But the number of rammings 
clearly depends on the lead width (Fig. 26). When the latter was small and many 
floes were compressed the ship had to ram frequently and even got repeatedly 
stuck. From 21 to 31 August the ship got stuck 15 times.

In addition to the ship's performance one hour observations were made for five 
different ice conditions for ice resistance calculations. During these occasions 
the local ice conditions and all ship-ice contact events were recorded, the 
thickness was monitored continuously and the thrust, propeller pitch and torque 
were logged in one minute intervals.


Figure 25: Percentage of daily time required for ramming
Figure 26: Number of rammings per mile of Progress versus lead width
Figure 27: Magnified AVHRR image distinctly showing long leads in the sea ice



3.4.7  Sea Ice Remote Sensing

A HRPT (High Resolution Picture Transmission) System on board Polarstern 
received AVHRR data of the NOAA-Satellites 12 and 14 from approximately 300 
overpasses. The images were used to monitor the ice conditions along the cruise 
track and to Support the ship's navigation. Later the scenes will be evaluated 
together with satellite data from the ERS-SAR and from the radar altimeter. An 
example of the obtained images is portrayed On Figure 17. The enlargement of the 
southern Laptev Sea on Fig. 27 reveals wide and rather long leads within the 
otherwise closed ice Cover. This information was used to optimize the ship's 
route in these basically severe ice conditions. Comparing the track of 
Polarstern with the satellite image taken some hours earlier some hints On the 
ice drift can be obtained. In addition to the NOAA data 21 images from the OKEAN 
satellite were received and stored for later analysis.

To improve the algorithms for satellite passive microwave signals of sea ice, 
radiometric measurements were performed near the ice surface.

The passive microwave signal of first-year and second-year ice was measured at 
15 stations at frequencies of 11, 21, 35 and 37 GHz with horizontal and vertical 
polarization under different environmental conditions (Table 2). 3 microwave 
radiometers (11, 21, 35 GHz) of the University of Bern (Switzerland) and one of 
the Arctic and Antarctic Research Institute, St. Petersburg (Russia) were 
applied.


Table 2:  Radiometer Stations

 __________________________________________________________________________

  Station No.  Date   Radiometric Measurements
  -----------  -----  ----------------------------------------------------
    41/018     28.07  11,21,35 GHz 20-70 deg., FY-ice, frozen puddle
    41/022     30.07  11,21,35 GHz 20-70 deg.
    41/029     01.08  11,21,35 GHz 20-70 deg.
    41/043     05.08  11,21,35 GHz 20-70 deg.
    41/046     06.08  11,21,35 GHz 20-70 deg., 50 deg. profile 12 m
    41/048     07.08  11,21,35 GHz 20-70 deg, profile 3 m
    41/052     08.08  1 1,21,35 GHz 20-70 deg.,
                      50 deg. with and without fresh snow layer
    41/055     09.08  1 1,21,35 GHz 20-70 deg.
    41/073     16.08  11,21,35 GHz 20-70 deg,
                      50 deg. with and without metal sheet
    41/080     19.08  11,21,35,37 GHz 20-70 deg.
    41/083     21.08  11,21,35,37 GHz 20-70 deg.,
                      50 deg. profile 10 m (1 1,21,35 GHz, Snow thickness)
    41/088     25.08  11,21,35 GHz 20-70 deg.,
                      40,50,60,70 deg. profiles 15 m, Snow thickness
    41/090     26.08  11,21,35 GHz 20-70 deg.,
                      20,45,55,60 deg. profiles 5 m,
                      50 deg. profile 15 m,
                      snow thickness (new snow, refrozen snow)
    41/100     02.09  1 1,21,35 GHz 20-70 deg.,
                      50 deg. profile 55 m, Snow thickness
    41/103     03.09  11,21,35 GHz 20-70 deg.,
                      50 deg. profile 40 m,
                      30,40,60,70 deg. profiles 3 m
 __________________________________________________________________________


The radiometers were installed on a sledge at a height of about 1.8 m over   the 
ice surface. The angle of incidence could be changed between 20 and 70   degrees 
in steps of 5 degrees.
  
Additionally, profile measurements with a typical point spacing of 0.5 m were 
performed to analyze lateral changes in the microwave emissivity. The microwave 
signals along these profiles correlated significantly with the Snow thickness.

Detailed values for two floes are reproduced in Tables 3 and 4.

The signals of the different channels are obviously closely correlated.


Table 3:  Correlation coefficients for measurements at station 41/103

   __________________________________________________________________

          11h   21h   35h   11v   21v   35v  SnowTh        
         -----  ---  -----  ---  -----  ---  ------
    11h  1.000       0.939       0.899       0.972v   0.954    0.904
         0.665                              
    21h  0.940       1.000       0.981       0.921    0.989    0.975
         0.757                              
    35h  0.899       0.981       1.000       0.879    0.970    0.995
         0.786                              
    11v  0.972       0.921       0.879       1.000    0.951    0.890
         0.690                              
    21v  0.954       0.989       0.970       0.951    1.000    0.975
         0.755                              
    35v  0.904       0.975       0.995       0.890    0.975    1.000
         0.783                              
    SnT  0.665       0.757       0.786       0.690    0.755    0.783
         1.000                    
   __________________________________________________________________



Table 4:  Correlation coefficients for measurements at station 41/100 

   __________________________________________________________________

          11h   21h   35h   11v   21v   35v  SnowTh        
         -----  ---  -----  ---  -----  ---  ------
    11h  1.000       0.680       0.630       0.890    0.686    0.633
         0.367                             
    21h  0.680       1.000       0.955       0.804    0.967    0.940
         0.523                             
    35h  0.630       0.955       1.000       0.730    0.933    0.977
         0.446                             
    11v  0.890       0.804       0.730       1.000    0.842    0.771
         0.515                             
    21v  0.686       0.967       0.933       0.842    1.000    0.960
         0.427                             
    35v  0.633       0.940       0.977       0.771    0.960    1.000
         0.410                             
    SnT  0.367       0.523       0.446       0.515    0.427    0.410
         1.000                    
   __________________________________________________________________



3.4.8  Biological and Physical Sea Ice Properties

A total of 185 ice cores were taken at 23 locations for physical and biological 
investigations. Temperature, salinity, chlorophyll and meiofauna-organisms were 
determined. Grazing and growth rates of sea ice organisms were derived and 
cultures of sea ice organisms were established for future experiments. Three 
plankton samples were taken with a 20 µm net from the ice edge for comparisons 
with the pelagic community in the underlying water column. In addition, one 
sample was taken from new ice to investigate the colonization by meiofauna 
organisms.

Cores were drilled with a KOVACS ice corer (10 cm diameter). Ice temperatures 
were measured every 10 cm with a digital temperature probe inside the core 
immediately after drilling. The Same core was then cut into 10 cm segments. The 
melted segments were analyzed for salinity and chlorophyll. Additional ice cores 
from the Same site were cut into 10 to 2 cm thick segments for investigations on 
sea ice biota. For meiofauna-studies, the segments were melted in an excess of 
0,2 µm filtered sea water at 4°C to avoid osmotic Stress to the organisms. 
After complete melting, the sample was concentrated over a 20 µm sieve and 
either sorted alive under a dissecting microscope or fixed with Bouin's solution 
or formalin (1% end-concentration) for later sorting and taxonomic studies. 
Cultures of sea ice organisms were established from melted samples in culture 
flasks under a light-dark- cycle of 12:12 hours. Average core salinities between 
3 and 4 ‰ (Fig. 28) dominate the sample and the salinity profiles which are 
characteristic of summer desalinated ice, i.e. the upper 30 - 50 cm comprises 
very low salinities with slightly higher values below (Fig. 29). Four cores with 
average salinities < 2 ‰, were taken from areas of refrozen melt ponds and one 
core with an average salinity of 5.2 ‰ was taken from a site near the floe 
edge.

The temperature profiles were determined by the relatively high air temperature 
near the top and the freezing water temperature at the bottom. The density of 
core segments was calculated from volumetric and mass measurements. The average 
density for all segments was 876.3 kgm-3 with a maximum of 988.4 kgm-3 and a 
minimum of 71 6.9 kgm-3. All density profiles showed a trend of increasing 
density with core depth. From these bulk properties, the brine and gas volumes 
of the cores can be calculated.


Figure 28: Mean Salinity distribution in sea ice cores
Figure 29: Typical vertical salinity profile in sea ice during ARCTIC '96 


At 17 stations, the temperature and salinity of the underlying water columns was 
measured using a portable conductivity-temperature (CD) device. The probe was 
passed through the bore hole on a graduated cable and the CD profile of the 
water was measured to a maximum depth of 15m. It was anticipated that a sharp 
halocline would be observed where fresh melt water overlies the more saline 
oceanic surface water. This feature was not observed at any of the stations and 
all profiles showed a uniform salinity over the full depth. Measured salinities 
ranged from 34.2‰ to 32.3‰. This absence of under ice melt water may be 
explained by the low surface ablation. The salinity of surface water along the 
cruise track (Fig. 30) is separated into two distinct groups; stations 207-220 
with an average 33.9‰ ±0.3 and stations 223-246 with an average 32.7‰ ±0.3. 
The saline Barents Sea water (207 - 220) differs from the fresher surface layer 
which is likely to be modified by river run-off. Variability within these two 
groups is attributed to salinity variations by melt water. The meiofauna 
community is dominated by ciliates but rotatoria and a few nematodes are also 
present as indicated in Fig. 31 and 32. Highest concentrations of organisms 
occur in the lowermost centimeters, but in core 208-07 a relatively high 
concentration of ciliates was also found in the upper 20 cm. Compared to earlier 
investigations, the abundance of metazoans in the ice community of these cores 
was lower, but whether this holds true for the whole region has to be Seen from 
the remaining samples. 


Figure 30: Surface water salinity along the cruise track
Figure 31: Depths distribution of the detected meiofauna in sea ice
Figure 32: Same as Fig. 31 


Sea ice organisms are generally small in size due to the structure of their 
habitat, the brine pockets and channels inside the ice. Small protozoans and 
metazoans are regarded to have a disproportionately high rate of growth, 
metabolism and feeding, so their role in the "in ice food web" may be 
significant. Quantitative Information about fluxes of organic carbon is 
restricted to measurements of total production of algae and bacteria using 
radioactive tracers. In most of these experiments ice organisms are kept in 
water, and the influence of ice is neglected. 

Serial dilution experiments (Laundry and Hassett 1982) were conducted to 
estimate growth and feeding rates of ice organisms. For this purpose ice core 
sections were melted and sea salt was added. In 14 out of a total of 28 serial 
dilution experiments ice was present in the bottles. The experiments were run 
over periods of 3 to 10 days in an incubator at about -2°C and with a 20 - 40 
mE m-2s-1 light intensity (PAR). Growth and grazing rates were calculated from 
biomass measurements (chlorophyll a) and cell counting (Fig. 33). 

doubling time autotrophe organisms: 7,35 days, grazing rate: 5.68 days

doubling time autotrophe organisms: 5.40 days, grazing rate: 5.91 days


Figure 33: Apparent growth in serial dilution experiments of ice organisms in 
           pure water (top) and in water with ice (bottom) 



3.5  Marine Biology
     (AWI, IPO, AARI, MMBI)

3.5.1  Phyto- and Zooplankton Ecology and Vertical Particle Flux

The distribution of phyto- and zooplankton in the water column was measured 
along the entire cruise track to extend the existing data bases of the Arctic 
shelf seas which were collected during the recent years. Of particular interest 
are:

• regional differences in the seasonal distribution Patterns of phyto- and 
  protozooplankton as well as interannual variations,
• the influence of the physical and chemical conditions and of nutrient 
  availability on marine primary and secondary production,
• the effects of sea ice on the pelagic food web,
• the relationship between algal biomass and grazing pressure,
• the vertical transport of organic matter into deeper layers and to the sea 
  floor.

At 54 oceanographic stations water samples were taken by the rosette sampling 
system. On each station subsamples were obtained at twelve discrete depths from 
the surface (2.5 m) down to the 300 m - layer for the following values:

• Chl-a and phaeopigments: Pigment concentrations were measured on board with a 
  Turner Design Fluorometer after filtration of the samples, homogenization and 
  cold extraction in 90% acetone.
• Species abundance: Samples (ca. 200 ml) were fixed with hexamine-buffered 
  37,5% formalin (final concentration 1.0%). Microscopial analyses will be carried 
  out in the home laboratory to investigate the distribution of the phytoplankton.

At fewer stations additional samples were obtained in the upper 300 meters and 
in deeper layers to determine:

• Particulate organic carbon / nitrogen and biogenic silica: Samples were 
filtered On precombusted glass fiber filters (POC/PON) or cellulose acetate 
  filters (silicea) and stored at -20°C for later analysis in the home laboratory
• Proto- and microzooplankton as well as fecal pellets. The samples were fixed 
  with hexamine-buffered formalin (final concentration 2%) and will be analyzed 
  under the microscope at home laboratories.

Furthermore at the position 81° 4.5'N / 138° 54.0'E two moored sediment-traps 
(150 m below the surface and 150 m above the sea floor) were recovered which had 
been deployed one year ago to analyze the seasonal vertical flux of matter down 
to the bottom. Both traps had functioned accurately and the secured samples were 
stored at 4°C, they will be analyzed at home for the seasonal particle-flux. 

• Seston samples: The samples were filtered On preweighted glass fibre and stored 
  at -20°C for later analysis in the home laboratory.


3.5.2  Biomass Distribution (chlorophyll-a)

In general the chlorophyll-a values were quite low at positions with a high ice 
coverage. The level of 1 mg/l was never exceeded except on station 3 (see 
below), therefore no bloom event could be observed. Almost no chlorophyll-a was 
found in depths larger than 100 m.

On station 3 near Franz Joseph Land maximum-values for chlorophyll-a were 
detected (Fig. 34). The higher concentration was reached in the upper 20 m with 
1.92 mg/l. Most stations were dominated by higher values in the upper 10 to 20 m 
and an exponential decrease in the depths below. The profile at station 12 is 
typical for the chlorophyll-a distribution on the transect across the St. Anna 
and Voronin Troughs. In the deep basins the values were generally smaller than 
0.2 µg/l. Only the values at station 58 with an ice concentration of only 20% 
surmounted this limit. The profile of station 62 under 60% ice Cover is more 
typical for the inner Arctic.

Continental slope: At the continental slope of the Laptev Sea chlorophyll-a 
increased again up to 0.4 mg/l in spite of an ice coverage of about 90%.


Figure 34: Vertical chlorophyll-a-distribution in 4 different regions


3.5.3  Taxonomy and Spatial Distribution of the Microplanktonic Community
 
The samples of sea water obtained during the entire cruise were analyzed for 
microplankton. 200 ml of water were taken from the rosette sampler and preserved 
with 1% Lugol solution. After 3 days of sedimentation the samples were 
concentrated to the volumes of 2 - 3 ml. Identification and enumeration of 
microplanktonic organisms larger than 15 mm were carried out in the 0.1 ml 
counting chamber under the Amplival microscope. Size Parameters of cells of 
flagellates, ciliates and of most diatoms were measured individually with the 
ocular micrometer at the magnification of 400 and then biovolumes were 
calculated, from individual cell volumes. Microplanktonic organisms smaller than 
15 mm were also counted and measured. Some large representatives of the 
microplankton were enumerated and identified in the entire volume of samples. 
The data on the taxonomic composition, numbers and biomasses of microplanktonic 
organisms have been prepared during the cruise already.

132 species of microplanktonic organisms were identified in the present material 
namely 56 dinoflagellate species, 46 diatom species, 20 representatives of other 
taxonomical groups of flagellated protists, and 10 species of choreotrichous 
ciliates. Most of diatoms originated from ice ecosystems, whereas the 
overwhelming majority of flagellates and cilicates represented a typical pelagic 
assemblage inhabiting ice-free water. The composition of the dinoflagellates was 
typical for the North Atlantic pelagic ecosystem. Obviously microplanktonic 
biota are transferred to the Arctic Ocean with prevailing current systems. Here 
most of warm-water forms die off or transfer into resting stages. Both tend to 
sink towards deeper regions.

The observed microplanktonic community may be subdivided into two major 
components representing sufficiently autonomous subsystems of the ecological 
metabolism which are related to different structural compartments of the water 
column. The first one, predominated by obligatory autotrophic diatom 
populations, is related to the ice habitats and its populations seed the topmost 
layers of the water column. The second one is an assemblage of mixotrophic and 
heterotrophic microplanktonic organisms inhabiting the water column. The Open 
water parts were dominated by flagellates including the rich and rather 
diversified dinoflagellate assemblage. The dinoflagellates, together with the 
smallest fraction of heterotrophic flagellates, formed nearly all of the 
microplankton biomass.

The irregularities of ice fields create a complicated network of downward fluxes 
of living, dying off and dead particulate matter. Therefore, the primary 
production by autotrophic populations of the ice and ice-related communities 
results in a series of rather short impulses of particulate organic matter in 
the top layer of the Arctic Ocean.


3.5.4  Epipelagic Community

31 vertical hauls with a Bongo net were made from 100 m depth to the sea 
surface, to study the communities of the zooplankton, the size structure of 
Calanus sp. assemblages as well as euphausiids and chaetognaths.

The small copepods (prosome length < 0.5 mm) were abundant at all stations, with 
the exception of station 057, where the crustaceans from genus Calanus were more 
abundant. Appendicularians and ostracods were the second important taxonomical 
groups in term of abundance in the deep water area, and appendicularians and 
chaetognaths in the slope area.

The four assemblages of Calanus sp. were distinguished by prosome length 
structure (Table 5):

  (I) Station   031 - one modal class         (2.0 - 2.5 mm)
 (II) Stations  036 - 042 - two modal classes (2.5 - 3.0 and 6.0 - 6.5 mm).
(III) Stations  044 - 057 - two modal classes (3.5 - 4.0 and 6.0 - 6.5 mm)
 (IV) Stations  059 - 062 - one modal class   (3.5 - 4.0 mm)

The change of the size structure in Calanus sp. assemblages (Table 6) is a 
reflection of the differences in species and age composition of the assemblages.


Table 5:  Size structure (%) in the Calanus sp. assemblages 

        _____________________________________________________________

           Prosome    Assemblage  Assemblage  Assemblage  Assemblage
         length, mm       I           II         III          IV
         -----------  ----------  ----------  ----------  ----------
         1.00 - 1.50     1.1          1.4  
         1.51 - 2.00     2.2          5.8        1.4   
         2.01 - 2.50    34.0         14.2        5.6          8.3
         2.51 - 3.00    28.6         26.6        9.4         12.5
         3.00 - 3.50    26.4         10.8       17.5         31.2
         3.51 - 4.0      1.10        10.8       34.8         34.4
         4.01 - 4.5      3.30        3.3         6.9          6.2
         4.51 - 5.0                  7.5         2.7          2.1
         5.01 - 5.5      1.10        1.1         0.9          1.0
         5.51 - 6.0      1.10        5.0         5.4          2.1
         6.01 - 6.5       -          8.3        10.0         
         6.51 - 7.0      1.10        5.0         4.0          1.1
         7.01 - 7.5       -          1.6          -           1.1
             sum       100.0       100.0       100.0        100.0
        _____________________________________________________________
      

Euphausiids were represented by the boreal Atlantic species, Thysanoessa 
longicaudata. The body length of specimens was 12.5 - 20.5 mm and the age was 2 
- 4 years. The age structure of euphausiid pseudo-populations can be used to 
determine the age of the Atlantic water. 

Chaetognaths (arrow-worms) are important predators of the marine plankton 
communities. In the Arctic Ocean four species, Sagitta elegans, S. maxima, 
Eukrohnia hamata and E. bathypelagica. Sagitta elegans are dominant in the upper 
100 m layer, and three other species reside in bathypelagic levels. 

The Stages of maturity of Sagitta elegans at station 012 are reproduced in Table 6. 


Table 6:  Size structure of Sagitta elegans population at station 012 

   ______________________________________________________________________

    Body length, mm    Stage I     Stage II   Stage III  Stages I-II-III
    ---------------   ----------  ----------  ---------  ---------------
      10.0 - 15.0      2 (2.0%)                              2 (1.1%)
      15.1 - 20.0     12 (11.8%)                            12 (6.6%)
      20.1 - 25.0     28 (27.4%)   2 (3.1%)                 30 (16.4%)
      25.1 - 30.0     54 (52.9%)  22 (32.3%)   2 (16.6%)    78 (42.8%)
      30.1 - 35.0      4 (3.9%)   38 (55.8%)   8 (66.6%)    50 (27.4%)
      35.1 - 40.0      2 (2.0%)    6 (8.8%)    1 (8.4%)      9 (5.0%)
      40.1 - 45.1           
      45.1 - 50.0                              1 (8.4%)      1 (0.7%)
          Sum            102         68          12            182
   ______________________________________________________________________



3.5.5  Meso- and Bathypelagic Communities

The general Pattern of mesozooplankton distribution in the Arctic Ocean is well 
documented. Vertical changes in abundance, biomass and community structure are 
mostly a consequence of the marked stratification of the water column. The Polar 
Surface Water, Atlantic Layer and Polar Deep Water strongly differ in 
environmental factors and are inhabited by different zooplankton communities. 
The permanent ice coverage leads to a very short phytoplankton bloom and a low 
primary production. This results in a short pulsed flux of organic matter into 
the depth. Therefore the mesopelagic zooplankton community should be well 
adapted to long starvation periods.

In contrast to the life cycles of intensively studied dominant epipelagic 
species, e.g. Calanus spp., the ecological role and the adaptive strategies of 
meso- and bathypelagic species in the Arctic are unknown. These organisms are 
mostly omnivorous or carnivorous and have to rely On living and dead organic 
material sinking down from the euphotic Zone as a food resource.

Because previous investigations have shown that these meso- and bathypelagic 
communities represent roughly 2/3 of all Arctic zooplankton, they significantly 
influence the energy flux within the Arctic marine ecosystem. They affect the 
remineralisation of nutrients within the water column. As predators they have an 
impact on herbivorous zooplankton populations. Omnivores transform sedimenting 
organic particles by feeding on detritus and faecal material (coprophagy). In 
addition, they produce faecal pellets themselves and may modify the transport 
mechanisms of particular organic carbon. Faecal pellets form a large fraction of 
the entire sedimenting matter. Due to their properties, i.e. size, density and 
high energy content, faecal pellets seem to be an important component in the 
nutrient regime of the deep sea.

During this expedition the feeding ecology of meso- and bathypelagic zoo-
plankton species as well as trophic relationships within the pelagic realm and 
the impact of this zooplankton community on the particle flux within the water 
column was studied. Additionally the competition between bathypelagic species 
was investigated.

Along the cruise track 13 deep Bongo net hauls (mesh sizes 500/300 µm, 300/200 
µm) covering depths down to 2000 m were sampled in the Nansen, Amundsen and 
Makarov Basins. Individuals of abundant species were sorted out alive and kept 
in cold containers for later measurements and experiments. Gut evacuation rates 
(GER) of carnivorous, omnivorous or herbivorous feeding types were measured. The 
faecal material was collected and preserved for density measurements and LM and 
SEM investigations. During the following feeding experiments the Same 
individuals where fed with in situ algae, faecal pellets from the herbivorous 
Calanus glacialis and undetermined detritus (collected by a small net with 70 µm 
mesh size attached to the bongo net). Again faecal material was collected and 
preserved for comparison with in situ pellets. The results will allow a 
qualitative Statement on the feeding ecology of the investigated species and 
will deliver useful values to estimate the role of faecal pellets in the organic 
particle flux. Measurements of CIN, lipids and carbon isotope ratios will 
Support the understanding of the trophic dynamics in the mesopelagic realm.

The Bongo net samples also provided carnivorous specimens for starvation and 
feeding experiments on board, as well as for respiration measurements and 
biochemical analyses. The loss of lipids during starvation will allow to 
calculate individual energy demands. Respiration measurements offer a second 
independent opportunity to estimate energetic requirements. Feeding experiments 
conducted with different carnivorous and prey species elucidated the trophic 
relationships within the bathypelagic realm.

Additional material was collected by multiple opening/closing net (Multinet) 
hauls at five stations on the first transect across St. Anna Trough and Voronin 
Troughs (down to bottom) and at five stations in the Eurasian and Canadian 
Basins (maximum depth 3600 m). The samples were preserved in 4% formaline and 
will be analyzed in the Shirshov Institute, Moscow to confirm the presumed 
vertical distribution and to complete previous investigations.

The seven investigated mesopelagic copepod species were feeding On algae and 
faecal pellets, whereas epipelagic herbivorous copepods refused to consume 
faecal pellets. Detritus in form of marine Snow was accepted by one mesopelagic 
species. Two mesopelagic species were omnivorous with carnivorous tendencies. 
Comparative studies of in situ faecal pellets have shown that freshly produced 
faecal material of copepods has a roughly uniform shape, but may differ in 
coloration, optical density and size.

The size of a faecal pellet depends on the size of the animals, the gut fullness 
and the quantity of food. Colours of pellets may depend On the colour of guts. 
Since various copepods have a selective feeding behaviour the composition of 
faecal material is more or less specific for certain species. Density 
measurements will show, if the physical density of a faecal pellet is correlated 
to a species and its ontogenetic stages.

The analyses of the net samples showed that carnivorous zooplankton species were 
abundant throughout the entire area. While hydromedusae, ctenophores and 
chaetognaths were distributed in patches, carnivorous copepods were present at 
all stations, inhabiting even the surface layer. The experiments especially 
focused On Euchaeta spp., since this genus dominates the Arctic carnivorous 
copepods.



5.  Participating Institutions/Beteiligte Institutionen

 ___________________________________________________________________________

                                                                  No. of
  Country  Acronym  Institution                                Participants
  -------  -------  -----------------------------------------  ------------
  Germany    AWI    Alfred-Wegener-Institut                         13
                    für Polar- und Meeresforschung         
                    Am Handelshafen 12         
                    27570 Bremerhaven         
                             
                    AERODATA Flugmeßtechnik GmbH                     1
                    Forststr. 33         
                    38108 Braunschweig         
                             
             DWD    Deutscher Wetterdienst                           2
                    Seewetteramt         
                    Postfach 30 11 90         
                    20304 Hamburg         
                             
             HSW    Helicopter-Service                               4
                    Wasserthal GmbH         
                    Kätnerwe 43         
                    22393 Hamburg         
                             
             IfMH   Institut für Meereskunde                         2
                    der Universität Hamburg         
                    Troplowitzstr. 7         
                    22529 Hamburg         
                             
             IfMK   Institut für Meereskunde                         2
                    der Universität Kiel         
                    Düstembrooker Weg 20         
                    24105 Kiel         
                             
             IMKH   Institut für Meereskunde und Klimatologie        2
                    der Universität Hannover         
                    Herrenhäuse Str. 2         
                    30419 Hannover         
                             
             IPO    Institut für Polarökologie                       2
                    der Universität Kiel         
                    Wischofstr. 1-3, Geb. 12         
                    24148 Kiel         
                             
             IUH    Institut für Umweltphysik                        1
                    der Universität Heidelberg         
                    Im Neuenheimer Feld 366         
                    69120 Heidelberg         
                             
  Russia     AARI   Arctic and Antarctic                             3
                    Research Institute         
                    38, Ul. Bering         
                    199226 St. Petersburg         
                             
             MMBI   Murmansk Marine                                  2
                    Biological Institute         
                    17, Vladimirskaya St.         
                    Murmansk 183010         
                             
             OAP    Obuchov Institute                                1
                    of Atrnospheric Physics         
                    Pyzhevskiy Pereulok 3         
                    109017 Moscow         
                             
  Sweden     GU     Göteborg University                              7
                    Dept. of Oceanography         
                    Earth Science Centre         
                    41381 Göteborg         
                    Dept. of Analytical         
                    and Marine Chemistry         
                    41296 Göteborg         
                             
  Canada     BIO    Bedford Institute of Oceanography               3
                    P.O. Box 1006         
                    Dartmouth N.S. B2Y 4A2         
                             
  USA        UW     University of Washington, APL                    1
                    1013 NE 40th         
                    Seattle, WA 98105         
                             
             ESR    Earth & Space Research                           1
                    1910 Fairview E., no. 102         
                    Seattle, WA 98102-3699         
                             
             SIO    Scripps Institution of Oceanography              2
                    University of California, San Diego         
                    La Jolla, CA 92093-0214         
                             
             DLEO   Lamont-Doherty Earth Observatory                 1
                    of Columbia University         
                    RT 9W         
                    Palisades, New York, 10964-8000         
                             
  Finland    HUT    Helsinki University of Technology                1
                    Tietotie 1         
                    02150 Espoo         
                             
  U.K.       SPRI   Scott Polar Research Institute                   1
                    University of Cambridge         
                    Lensfield Road         
                    Cambridge, CB2 1ER         
                             
  Ireland    UCD    University College Dublin                        1
                    Dept. of Experimental Physics         
                    Belfield, Dublin 4         
 ___________________________________________________________________________



6  Participants / Fahrtteilnehmer

Name                       Institution        Nationality
-------------------------  -----------------  -----------
Abrahamsson, Katarina      GU                 Swedish
Andersson, Leif            GU                 Swedish
Auel, Holger               PO                 German
Augstein, Ernst            AWI                German
Bahrenfuß, Kristin         IfMK               German
Björk Göra                 GU                 Swedish
Buchner, Jurgen            HSW                German
Bussmann, Ingeborg         AWI                German
Chierici, Melissa          GU                 Swedish
Cohrs, Wolfgang            AWI                German
Cottier, Finlo Robert      SPRI               British
Darnall, Clark             UW                 USAmerican
Darovskikh, Andrey         AARI               Russian
Drübbisch, Ulrich          IfMH               German
Druzhkov, Nikolay V.       MMBI               Russian
Ekdahl, Anja               GU                 Swedish
Ekwurzel, Brenda           LDEO               USAmerican
England, Joachim           DWD                German
Fitznar, Hans-Peter        AWI                German
Frank, Markus              IUH                German
Fransson, Agneta           GU                 Swedish
Friedrich, Christine       IPÖ                German
Grachev, Andrey            OAP                Russian
Haas, Christian            AWI                German
Hiller, Scott              SI0                USAmerican
Hingston, Michael Patrick  BIO                Canadian
Hofmann, Michael           IMKH               German
Ivanov, Vladimir           AARI               Russian
Johnsen, Klaus-Peter       AWI                German
Jones, Edward Peter        BIO                Canadian
Larsson, Anne-Marie        GU                 Swedish
Lensu, Mikko               HUT                Finnish
Leon Vintro, Luis          UCD                Spanish
Lundström Volker           HSW                German
Lüpkes, Christof           AWI                German
Muench, Robin              ESR                USAmerican
NN (Ice Pilot)             Murmansk Shipping  Russian
NN (Observer)              Murmansk Shipping  Russian
Pivovarov, Sergey          AARI               Russian
Riewesell, Christian       HSW                German
Rudels, Bert               IfMH               Swedish
Schauer, Ursula            AWI                German
Scherzinger, Ti1           AWI                German
Schreiber Detlev           HSW                German
Schurmann, Mathias         AERODATA           German
Siebert, Holger            IMKH               German
Sonnabend, Hartmut         DWD                German
Strohscher, Birgit         AWI                German
Templin, Michael           AWI                German
Timmermann, Axel           AWI                German
Timofeev, Sergey           MMBI               Russian
Weissenberger, Jürgen      AWI                German
Wilhelm, Dietmar           IfMK               German
Williams, Bob              SI0                USAmerican
Zemlyak, Frank             BIO                Canadian



7.  Ship's Crew / Schiffsbesatzung

Profession                 Name
-------------------------  -----------------------
01. Captain                Greve, Ernst-Peter
02. 1. Officer             Pahl, Uwe
03. 1. Officer             Rodewald, Martin
04. Chief Engineer         Knoop, Detlef
05. 2 Officer              Grundmann, Uwe
06. 2 Officer              Spielke, Steffen
07. Medical Doctor         Bennemann, J.
08. Radioperator           Koch, Georg
09. 2 Engineer             Erreth, Mon. Gyula
10. 2 Engineer             Ziemann, Olaf
11. 2 Engineer             Fleischer, Martin
12. Electronic Technician  Lembke, Udo
13. Electronic Technician  Muhle, Helmut
14. Electronic Technician  Greitemann-Hackl, A.
15. Electronic Technician  Roschinsky, Jörg
16. Electrician            Muhle, Heiko
17. Boatswain              Clasen, Burkhard
18. Carpenter              Reise, Lutz
19. Sailor                 Winkler, Michael
20. Sailor                 Bindernagel, Knuth
21. Sailor                 Gil Iglesias, Luis
22. Sailor                 Pousada Martinez, S.
23. Sailor                 Kreis, Reinhard
24. Sailor                 Schultz, Ottomar
25. Sailor                 Burzan, G.-Ekkehard
26. Sailor                 Pulss, Horst
27. Technician             Arias Iglesias, Enrique
28. Technician             Preußner, Jörg
29. Technician             Ipsen, Michael
30. Technician             Husung, Udo
31. Technician             Grafe, Jens
32. Storekeeper            MüllerK laus
33. Chief Cook             Haubold, Wolfgang
34. Cook                   Völske Thomas
35. Cook                   Yavuz, Mustafa
36. 1. Stewardess          Jürgens, Monika
37. Stewardess/Nurse       Dähn Ulrike
38. Stewardess             Czyborra, Bärber
39. Stewardess             Deuß Stefanie
40. Stewardess             Neves, Alexandra
41. 2. Steward             Huang, Wu Mei
42. 2. Steward             Mui, Kee Fung
43. Laundryman             Yu, Kwok Yuen





DATA PROCESSING NOTES

Date        Contact   Data Type   Event

2010-03-25  Muus      BTL         Data are online 
----------  -------   ---------   -----------------------------------------------------------------------------------------------------------------------------------------              
            a96 b9ttle file notes March 24, 2010   D. Muus
            EXPOCODE 06AQ19960712
            SECT_ID  ARKXII
            Cruise Name ARKTIS XII
            
            Merged Nutrient, CFC and CO2 data from CARINA Exchange File into ODF Exchange File containing CTD trip data, bottle salinity and oxygen.
            CARINA file has BIO number as bottle number and no sample number.
            ODF file has ODF bottle number as bottle number and sample number.
             Replaced ODF bottle number with BIO sample number taken from file "bionum.asc" found in ODF cruise directory on STS computer
             Added SECT_ID "ARKXII"(From the Cruise name). No SECT_ID in CARINA file. SECT_ID is "NA" in ODF file.
            
            odfnotes 100324/dm
            From: /Users/dave/ZBACKUP/SWIFT99.01.02.05/SWIFT01/a96/NA_hy1.csv
                                                                  /a96hy.txt
                                                                  /a96su.txt
            
            STNNBR 47 CASTNO 1 SAMPNOs 7 and 8 deleted. No BIO number for use as BTLNBR. No record of samples taken.
            STNNBR 72 CASTNO 1 SAMPNOs 28 and 29 deleted. No BIO number for use as BTLNBR. No record of samples taken.
             CCHDO merge program stops with BTLNBR -999 even though no samples to be merged.
            
            EXPOCODE changed from 06AWARKXII to 06AW19960712.
            SECT_ID changed from NA to ARKXII.
            
            Deleted Station 83 from ODF bottle file, Seabird CTD trip data not corrected. Other Seabird CTD cast, Station 53, not in ODF file.
            
            carinanotes 100322/dm
             Exchange file, 06AQ19960712_hy1.csv, dated May 29, 2009, was taken from Project CARINA section of CCHDO website.
             BOTTLE,20090513PRINUNIVRMK
             Changed pH parameter order from "PH_SWS,PH_TEMP,PH_SWS_FLAG_W" to "PH_SWS,PH_SWS_FLAG_W,PH_TMP" so JOA associates flag with PH_SWS instead of PH_TMP.
            
             Changed CASTNO Station 31 BTLNBR 166014-165996 CTDPRS 11-485db from 1 to 2 to match ODF & ConOps. No info on Cast 1.
             Changed CASTNO Station 38 BTLNBR 166219-166189 CTDPRS 10-3060db from 1 to 2 to match ODF & ConOps. 
               ConOps for Sta 38 Cast 1 shows 13 sample bottles from 0 to 300 MWO with Note:"No BIO#'s"
             Changed CASTNO Station 41 BTLNBR 166340-166410 CTDPRS 282 -3617db from 1 to 2 to match ODF & ConOps 
             Changed CASTNO Station 43 BTLNBR 166456-166424 CTDPRS 10-801db from 1 to 2 to match ODF & ConOps 
             Changed CASTNO Station 44 BTLNBR 166490-166457 CTDPRS 10-3762.0db from 1 to 2 to match ODF & ConOps, Cast 1 is "Shallow Phyto (No BIO ids)
             Changed CASTNO Station 46 BTLNBR 166562-166527 CTDPRS 10-4206.0db from 1 to 2 to match ODF & ConOps, Cast 1 12 bottles, No sample log - Phyto?
             Changed CASTNO Station 47 BTLNBR 166604-166569 CTDPRS 10-4206.0db from 1 to 2 to match ODF & ConOps, 
             Changed CASTNO Station 48 BTLNBR 166662-166630 CTDPRS 10-4206.0db from 1 to 2 to match ODF & ConOps, 
             Changed CASTNO Station 50 BTLNBR 166734-166699 CTDPRS  9-4450.0db from 1 to 2 to match ODF & ConOps, Cast 1 is "phyto only"
             Changed CASTNO Station 52 BTLNBR 166806-166771 CTDPRS 10-4455db from 1 to 2 to match ODF & ConOps. Cast 1 "Shallow Phyto no BIO#s".
             Changed CASTNO Station 52 BTLNBR 166806-166803 CTDPRS 10.1-40.8db to BTLNBRs 166807-166804. No 166803 in Sample Log. 
               ODF BIONBR vs ODF Sample Number file shows:
              Sta Ca ODF# BIO#  WireOut(ConOps)
               52  2  32 166802 60
               52  2  33 166804 40
               52  2  34 166805 30
               52  2  35 166806 20
               52  2  36 166807 10
               ConOps notes indicate CTD problems Station 52 Cast 2. Assuming ODF bottle file correct.
              Changed CASTNO Station 54 BTLNBR 166851,166848-166844 CTDPRS 11-80db from 1 to 2 to match ODF & ConOps
              Changed CASTNO Station 55 BTLNBR 166923-166893 CTDPRS 10-799db from 1 to 2 to match ODF & ConOps
              Changed CASTNO Station 56 BTLNBR 166923-166893 CTDPRS 10-799db from 1 to 2 to match ODF & ConOps
              Changed CASTNO Station 58 BTLNBR 167050-167015 CTDPRS 10-4020db from 1 to 2 to match ODF & ConOps. Cast 1 "Shallow Phyto no BIO#s".
              Changed CASTNO Station 62 BTLNBR 167186-167151 CTDPRS 10-1154db from 1 to 2 to match ODF & ConOps. Cast 1 "Seabird CTD/ADCP cast".
              Changed CASTNO Station 63 BTLNBR 167206-167187 CTDPRS 10-956db from 1 to 2 to match ODF & ConOps. No info on Cast 1.               
              Changed CASTNO Station 64 BTLNBR 167230-167207 CTDPRS 10-863db from 1 to 2 to match ODF & ConOps. No info on Cast 1.               
              Changed CASTNO Station 72 BTLNBR 167514-167475 CTDPRS 400-3900db from 1 to 2 to match ODF & ConOps. 
              Changed CASTNO Station 73 BTLNBR 167551-167569 CTDPRS 10-150db from 1 to 2 to match ODF & ConOps. 
              Changed CASTNO Station 78 BTLNBR 167742-167736 CTDPRS 10-40db from 1 to 2 to match ODF & ConOps. 
              Changed CASTNO Station 82 BTLNBR 167912-167889 CTDPRS 10-800db from 1 to 2 to match ODF & ConOps
              Changed CASTNO Station 87 BTLNBR 168092-168062 CTDPRS 300-3067db from 1 to 2 to match ODF & ConOps
              Changed CASTNO Station 88 BTLNBR 168129-168098 CTDPRS 10-1514db from 1 to 2 to match ODF & ConOps




