Bremerhaven, 9 June 2010. Tomorrow the Polarstern research vessel sets off on its 25th Arctic expedition. From Bremerhaven it will first set course for the Greenland Sea, where primarily oceanographic work is on the agenda. After a short stop in Longyearbyen (Spitzbergen) the Polarstern will sail to the so-called HAUSGARTEN of the Alfred Wegener Institute and to Fram Strait on 30 June. There scientists will carry out long-term studies and further oceanographic measurements. On 31 July the third leg, involving geoscientific research, will start in Reykjavik, Iceland and take the vessel to northern Baffin Bay (Canada). Over 120 scientists and technicians from six nations are taking part in the three legs of the expedition. The Polarstern is expected back in Bremerhaven on 10 October.
“The hydrographic work on the first leg makes a major contribution to long-term series of measurements that are indispensable for climate research,” explains Chief Scientist Dr. Gereon Budéus, oceanographer at the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association. For over ten years now he and his colleagues have been conducting investigations in the Greenland Sea on the intensity and influence of winter convection, which determines the distribution of heat and salt in the region under study and controls renewal of the deepest layers in the ocean. Furthermore, biologists are studying plankton, i.e. tiny creatures that float in the water column, in the region investigated. The microscopically small animals and algae from three different biogeographic climate zones (polar, Arctic and Atlantic) occur relatively close together here. Research focuses on whether certain species continue to spread or occur less frequently because of altered environmental conditions.
On the second leg in July scientists will study how the Arctic marine ecosystem reacts to global climate change in the deep-sea long-term observatory of the Alfred Wegener Institute, the so-called HAUSGARTEN. Embedded in numerous national and international projects, researchers have been taking samples and conducting experiments on the continental shelf off Spitzbergen at a water depth between 1000 and 5500 metres on a regular basis for over ten years. These studies examine, for instance, how the deep-sea ecosystem reacts to the decline in sea ice and thus to related changes in the food supply. In addition, the scientists will continue long-term hydrographic studies in Fram Strait, the only deepwater link between the North Atlantic and the central Arctic Ocean. Oceanographic moorings here record data on the salt concentration and temperature of the water. They make it possible to quantify the exchange of water masses between the two marine regions.
The third leg starts from Reykjavik at the end of July and will take the Polarstern to Canadian waters. Scientists under the direction of the Federal Institute for Geosciences and Raw Materials (BGR) will study the geological structures and tectonic development of northern Baffin Bay and the adjoining Canadian and Greenland continental margins. They want to reconstruct when and how Baffin Bay opened in the course of the Earth’s history and what geological processes took place during Greenland’s separation from North America. The geodynamic reconstruction of the opening of this shallow-water link between the Arctic Ocean and the Atlantic forms the basis for palaeobathymetric models. The latter serve to provide a detailed conception of how global current and sedimentation processes have changed. These efforts will contribute to a better understanding of the development of the palaeoclimate and sedimentary basins in the Arctic.
Over 120 scientists and technicians from six nations are taking part in the three legs of the expedition. After four months in the Arctic the Polarstern is scheduled to return to its homeport of Bremerhaven on 10 October.
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Your contact in the Communication and Media Department of the Alfred Wegener Institute is Folke Mehrtens (tel. 0471 4831-2007; e-mail: Folke.Mehrtens@awi.de)
The Alfred Wegener Institute conducts research in the Arctic, Antarctic and oceans of the high and mid latitudes. It coordinates polar research in Germany and provides major infrastructure to the international scientific community, such as the research icebreaker Polarstern and stations in the Arctic and Antarctic. The Alfred Wegener Institute is one of the sixteen research centres of the Helmholtz Association, the largest scientific organisation in Germany.