Expedition- and Divereports

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23.03.2015: Antarctic dive mission 2015 at Carlini Base

(Photo: Anders Torstensson)
Francesca Pasotti takes water samples from an incubation chamber.
(Photo: Anders Torstensson)

After some years of abstinence of an AWI dive team at the Dallmann Laboratory/ Carlini Station at Potter Cove (King George Island, Antarctic) we could successfully perform all planned diving tasks during our expedition Ant Land 15/16.

This year’s campaign includes several highlights. First of all it was the first time that an international dive team under the aegis of the AWI dove together, namely Francesca Pasotti (Ghent University, Belgium), Anders Torstensson (University of Gothenburg, Sweden) and Ralf Hoffmann (AWI, Germany), under the supervision of Argentine army divers. This was possible due to a risk assessment including the strictest rules for scientific diving of each country, which is unique until now. A second highlight was the first time performance of in situ incubations and in situ measurements of oxygen profiles in the Potter Cove to detect the oxygen consumption of micro-, meio- and macrofauna benthic sediment communities. These measurements were performed at three different sites, which differ in time of being ice-free from the shrinking Fourcade Glacier. A comparison of the results will give insights in the development of sediment communities and associated benthic biogeochemistry in a changing Antarctic environment.

In total 68 dives were performed with a sum of over 28 h of diving. The main tasks were the deployment and recovery of benthic chambers, power supply and a profiler frame. Besides these tasks water samples from the benthic chambers and different sizes of sediment cores were taken as well as photo surveys and macroalgae collections performed. All dives were supported and guided by the argentine divers Alfredo Torres and Ezequiel Tulian

We like to thank Philipp Fischer, Maria Asplund, Alain Norro and Willy Mercury for creating the scientific diving risk assessment which represented a complex and unique international exercise, Katharina Zacher, Angela Wulff, Ulrike Braeckman and Nadja Küpper for being such great colleagues during our stay and last but not least Oscar Gonzalez, Gabriela Campana, Francisco Ferrer and the whole Carlini-Family for all the support.

Francesca Pasotti, Anders Torstensson & Ralf Hoffmann, March 2015

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05.01.2015: Antarktis Tauchexpedition ANTXX-2 / PS89

Im Rahmen der Polarsternfahrt  ANTXXX-2 / PS89 wurden im Januar 2015 erstmals Tauchgänge von der deutschen Antarktisstation Neumayer III aus durchgeführt. Im Rahmen der Expedition wurden Verfahren und Techniken zur Lokalisierung und Bergung von wissenschaftlichen Geräten durch eine etwa 3m dicke Meereisschicht erprobt. Die Neumayer-Station des Alfred-Wegener-Institutes erwies sich dabei als sehr gute logistische Plattform für Untereis-Tauchgänge in der Atka-Bucht. Im Rahmen der Mission wurden auch Prospektionstauchgänge bis zu einer Wassertiefe von 10 m und bis zu 60m unter das Meereis durchgeführt. Dabei konnte auch die Situation des Tauchens unter der 2-3 m starken sog. „Plättcheneis"-Schicht erprobt werden.  

Neben der reinen Methodenerprobung wurde zusätzlich ein kurzer biologischer Survey der Untereisfauna der Atkabucht durchgeführt. Es zeigte sich eine erstaunlich diverse Gemeinschaft mit Krill, Amphipoden, Fischen, Schwämmen und verschiedenen Anthozoenarten die sich in der Nähe, auf oder in der  Plättcheneisschicht aufhielten.

Zusammenfassend lässt sich feststellen, dass sich die vom AWI Tauchzentrum teilweise erstmals eingesetzten Geräte und Methoden zum wissenschaftlichen Tauchen in der Antarktis als belastbar und sicher gezeigt haben um Untersuchungen am oder unter mehrjährigem Eis durchzuführen.

Das AWI Tauchzentrum bedankt sich ganz herzlich bei der Besatzung der Neumayer III Station für die großartige Unterstützung während unseres Aufenthaltes und wünscht insbesondere den Überwinterern alles Gute für das kommende Jahr.

Christoph Walcher, Marco Warmuth & Philipp Fischer

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The 2014 AWI dive mission on Svalbard successfully finished end of September.

On September 29th the AWI dive group closed the 2014 Arctic dive season at the joined German / French AWIPEV-Station in Ny Ålesund on Svalbard.

Due to the fact that West-Spitsbergen was under the influence of the upcoming winter already since early September the last dives in the Kongsfjord area were conducted under real Arctic conditions such as low temperature, snowfall, strong wind and icy crusts on boat and equipment.

The 2014 diving campaign started in early June with a small group of divers arriving in Ny Ålesund to prepare the dive-locker, the dive-boat and the rescue chain as well as to check and test the decompression chamber and the diving equipment. Until the end of September a dive group of minimum 3 scientific divers was permanent on site to support a wide variety of scientific projects in the Kongsfjord area. During the campaign a total of 10 AWI related long- and short-term projects were supported by the divers mainly by taking biological samples, installing and maintaining underwater experimental set-ups and carrying out measurements or taking pictures and videos.

Beside this, a new challenge for the scientific divers was the support of an archaeological project dealing with anthropogenic traces underwater carried out by the Netherlands Arctic Institute in cooperation with AWIPEV. During these dives a specified area around the former marble mining site “Ny London” (Bloomstrandhalvoya) was investigated and archaeologically relevant findings had to be named, described, photographed and surveyed. A bulk of technic-related remainings were found and documented which gave some hints on the comprehensive activities during the mining period about 100 years ago.

Furthermore the divers conducted additional dives for other scientific institutes located in Ny Ålesund such as the Norwegian North Polar Institute (biological samples) and the Italian station, KingsBay and the Korean Polar Institute (all technical support dives).

The last days of the season were dedicated to the necessary maintenance and repair work at the AWIPEV Underwater Fjord Observatory. Some repairs had to be carried out at the installation and two new additional scientific instruments from the MPI Bremen and the AWI Helgoland were installed and connected to the underwater node.

All in all, a total of 11 AWI divers and two dive mission leaders (Max Schwanitz and Christoph Walcher) were alternating on site during the entire season. By conducting 259 dives they were able to fulfill all scientific requests and demands.

Max Schwanitz, October 2014

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09.07.2014: Report of two Bachelor students of the University of Oldenburg at AWI-CSD.

Between 22th of April and 30th of June Dina Biehn and Miriam Lienkämper stayed at the centre for scientific diving of the Alfred-Wegener-Institute at Helgoland. We are two Bachelor students from the University of Oldenburg and also scientific divers. At Helgoland we were collecting data for our Bachelor Theses about the competition between native and the invasive alga Sargassum muticum. Therefore we had an in situexperiment at the “MarGate” experimental field 400m northeast of Helgoland and an aquarium experiment at “Haus A”. To evaluate the competition of the algae we measured the weight, the length and the efficiency of photosynthesis with our Diving-PAM.
For our measurements, dives, preparation and everything else we had always support from the colleagues of the dive center. Therefore we are very thankful.