During the third week Polarstern ran a section north of the Kara Sea along 61°E from the central Nansen Basin towards the south.

The research vessel Polarstern is now sailing in the Barents Sea gathering research data for DAMOCLES.

The research vessel Polarstern is now sailing in the Barents Sea gathering research data for DAMOCLES.


This region belongs to the Russian “Exclusive Economic Zone” (EEZ), which is regulated by the International Law of the Sea, and extends to 200 nm from any coast, whether of a continent or an island. All along the rim of the Siberian shelf seas groups of islands like Franz Joseph Land, Severnaya Zemlja, etc, are situated so that the Russian EEZ extends far into the central Arctic Ocean. To carry out research in an EEZ, permission of the respective country is required. Such clearance is typically only a formality and, according to the Law of the Sea, must be granted unless severe reasons speak against it. There are a few countries that, for whatever reason, are enormously reluctant in giving this clearance and thus exclude large areas of the oceans from international research. Also, the Russian authorities have denied, after a short period of Perestroika in the early nineties, the permission to work in their EEZ for the past nine years – which was a decade of huge climate change in the Arctic. Now, during the International Polar Year 2007/08, the curtain has opened again and we are very glad to be able to work in this region that is of such importance with respect to oceanography, biology and geology.

At present, as during the quaternary (the past 1.6 millions years), the Kara Sea is an important area of the Arctic. Huge Siberian rivers enter the ocean in the Kara Sea, and a branch of Atlantic Water inflow passes through and flows from the shelf to the deep sea. Currently, it is unclear how various ice ages progressed in the Arctic and how they modified the continental run-off and the Atlantic Water flow. We also do not know what the interglacial conditions looked like here. Until now, no sediment cores had been collected from the northern Kara Sea that could provide answers to these questions. Was the drainage of Siberia to the north blocked during the last glaciation by large glaciers? In this case, the melt water of the receding glaciers would have spilled into the Arctic Ocean in a huge splash. Or was the Kara Sea open and the continental precipitation could steadily run off northwards as it does today?

Whatever happened – it should be manifested in the sediments at the continental slope. Our geologists eagerly watched the signal of the Parasound that displays the echo sounding of the upper 20 m of the sediment. Often they looked disappointed because the signal was clearly that of deposited turbidites, which are made of mud avalanches along the steep slope that were released by glaciers or strong currents. Such sediments are a wild mixture of everything and do not allow one to distinguish between individual layers by differences in microfossils, grain size or other parameters that represent different climate states. Eventually, a suitable site was discovered – but when the very first box core came back on deck it was damaged! However, after this flop the results grew considerably, culminating towards the middle of the week. On Wednesday a core was taken at 1000 m water depth with a “Kastenlot” which provides an extra large diameter. The core that was collected was more than 4 m long and contained a record of up to 160.000 years for analysis in the home laboratories. The sediment color allows the scientists to speculate about the several changes between glacials and interglacials seen in the core.

In the center of action one often can not see very far and thus we learned only from from back home that, after 2005, this year is going to show a new record minimum of ice cover. This fits well with our situation: compared to a Polarstern cruise in 1996 when we had a hard time to get through the ice here north of … Island, we now pass easily in view of completely open water beyond the ice edge. An ice station that was scheduled for today had to be cancelled twice – each time that we approached a flow it broke into pieces.

In the center of action one often can not see very far and thus we learned only from from back home that, after 2005, this year is going to show a new record minimum of ice cover. This fits well with our situation: compared to a Polarstern cruise in 1996 when we had a hard time to get through the ice here north of the tiny Ushakova Island, we now pass easily in view of completely open water beyond the ice edge. An ice station that was scheduled for today had to be cancelled twice – each time that we approached a flow it broke into pieces.

A couple of flue germs sneak through the ship causing uneasiness here and there. But we are sure to get the bacteria under control soon.
Aug 23, 2007
Ursula Schauer
Dec 8, 2008

Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies