Last October the Polarstern, which is operated by the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association, left Bremerhaven heading for Punta Arenas, Chile. From there it set off on a two-month cruise through the polar South Pacific to Wellington. The first stop in New Zealand was an opportunity for a reception held on the research icebreaker by the Alfred Wegener Institute and the German Embassy. The following third leg took the vessel back to Punta Arenas after a cruise lasting over two months. From there the Polarstern cast off on 7 April and set course for its homeport Bremerhaven, where it was scheduled to arrive with the morning high tide on Monday, 17 May.
The focus of the two legs Bremerhaven - Punta Arenas and back was on investigations of the interactions between ocean and atmosphere. Scientists of the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel together with partners from other institutes tested an autonomous measuring system that is envisaged for operation on board freighters and research vessels in the long term.
The leg from Punta Arenas to Wellington under the direction of Dr. Rainer Gersonde from the Alfred Wegener Institute was devoted to marine geological research. The scientists on board took a total of 1,000 metres of sediment cores having a weight of around 11 tons. The unique material will provide detailed information for the first time on the climate history of the last 400,000 to 4 million years in this region that has hardly been researched to date, but is important for climate development. Among other things, evaluation of the cores will focus on the evolution of the Antarctic circumpolar current, sea ice distribution, changes in greenhouse gas concentrations as well as melting events in the West Antarctic ice shelf with their impacts on global oceanic circulation.
On the way from New Zealand to Punta Arenas researchers under chief scientist Dr. Karsten Gohl primarily took geophysical measurement profiles along the West Antarctic continental margin in order to study the development of the West Antarctic ice shelf. The main area of work was Pine Island Bay, known for the accelerated retreat of the glacier systems that have been observed there since recently. Oceanographic investigations, geothermal heat-flow measurements and geological sampling of sea sediments and on the mainland supplemented the research programme. Unusually favourable ice conditions enabled an unparalleled yield of data and samples in this area that is normally difficult to access and has therefore scarcely been researched. They form the basis for future forecasts of the development of the West Antarctic ice shelves, which are of great importance for the global rise in sea level.
After the usual maintenance and repair work at the shipyard in Bremerhaven the Polarstern will set off on the 25th Arctic expedition on 10 June.
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.
Contact
Folke Mehrtens
Communication and Media Department of the Alfred Wegener Institute
Phone: +49 471 4831 - 2007
Email: medien(at)awi.de
