Research Vessel Polarstern setting out for the Arctic - Focusing on changes in the ice cover, ocean currents and effects on the marine biota

Bremerhaven, 5 June 2014. On Friday evening, June 6, 2014, RV Polarstern will set sail for the Arctic Ocean. 52 scientific expedition participants, dispatched by institutions in five countries, and a crew of 43 are going to start for the four-weeks expedition. The destination is the Fram Strait, in the waters between Greenland and Spitsbergen. This strait forms the only deep gateway between the Arctic Ocean and the North Atlantic. The researchers will be examining longer-term physical, oceanographic, chemical and biological changes, reaching from the atmosphere to the depths of the ocean.

For 15 years, now, the Alfred Wegner Institute, Helmholtz Centre for Polar and Marine Research (AWI), has operated AWI-HAUSGARTEN, a deep-sea observatory west of the island of Spitsbergen. And for about 17 years it has conducted long-term studies in the northern section of the Fram Strait, at 78.8° north.

The purpose of the oceanographic work in the Fram Strait is to quantify variations in the water-mass and heat exchange between the northern North-Atlantic and the central Arctic, as well as in the circulation within the Fram Strait.. AWI scientists, working in cooperation with the Norwegian Polar Institute, measure temperatures, salinity, oxygen levels, and marine currents. For this purpose they use moored as well as sea gliders and autonomous profiling floats. The moorings have to be recovered at regular intervals and then reinstalled. This is necessary to read out the recorded data and to replace the batteries used to supply power. The oceanographic observations make for a better understanding of the complex circulation patterns in the Fram Strait. “For this purpose we are now, for the first time, placing additional moorings on the East Greenland Shelf,” reports Dr. Benjamin Rabe of the Alfred Wegener Institute. “These measurements are intended to examine the potential influence of the warm water in the West Spitsbergen Current on a Greenland glacier, reaching into the sea, at 79.5° north,” the oceanographer explained.

In addition to the ocean currents, the scientists are also interested in the organic substances transported through the Arctic by the water or by the sea ice. AWI researchers are studying this with Russian colleagues and with researchers from the GEOMAR Helmholtz Centre for Ocean Research in Kiel within the “Transdrift” project, financed by Germany’s Federal Ministry for Education and Research. “We wanted to determine which substances the sea ice is introducing to the nutrient-poor deep waters,” said expedition leader Dr. Ingo Schewe. “To do this, we will be placing sediment traps in different water depth along the continental slope east of Greenland. They will be collecting organic matter stemming from plant and animal residues released by the melting of the ice,” the AWI deep-sea ecologist continued. Parallel to this, biologists, geologists and chemists will be examining ecological processes in the sea ice itself, beneath the ice, and on the ocean floor. In addition atmospheric researchers are investigating the boundary between the Arctic waters and the atmosphere.

During their later analyses, the scientists will compare the data gathered in the Fram Strait with values measured in the Laptev Sea, a marginal sea off the coast of Siberia. On the one hand, a great deal of sea ice is formed there. On the other hand, the large Siberian rivers transport organic material to the coasts, so that the freezing ice receives additional nutrients from the sediments on the coast. It is hoped that the comparative analysis of the data from the Laptev Sea and the Fram Strait will permit conclusions as to how these influx and efflux regions of the transpolar ice drift are coupled to one another.

To date, the AWI deep sea researchers had concentrated their long-term observations and experiments on the HAUSGARTEN observatory on the continental slope to the west of Spitsbergen. In future, they intend to pay greater attention to Greenland’s eastern coast. There the cold water from the Arctic Ocean flows into the North Atlantic while, near Spitsbergen, the warmer Atlantic waters flow northward, into the Arctic. As a complement to the work at HAUSGARTEN, researchers in the FRAM consortium, sponsored by the Helmholtz Association, want to establish stations with moorings anchored on the seabed at depths of between 1,000 and 2,500 meters. In this way they want to study the ecological consequences of climate change in these two key regions in the Fram Strait. The first instruments are to be tested and installed during the current Polarstern expedition.

“I am happy that we are finally taking off,” said expedition leader Ingo Schewe. He and his team had in fact intended to set sail for the Arctic in mid-May. However, during routine maintenance of the Polarstern in Bremerhaven, signs of wear were discovered at the drive shaft bearings and that mandated replacement. As a result, the workers at the shipyard, the shipping company and the AWI logistics department – along with the researchers themselves – had to wait for the new bearings to be delivered, installed and tested. “I am glad the damage was discovered here at an early stage, and that it was acted accordingly. Thanks to the flexibility of everyone involved, we will hopefully be able to carry out our research programme successfully, in spite of some adjustments,” Schewe noted. The expedition is planned to end on July 3 in the Norwegian port of Tromsø.

Notes for Editors: Please find printable images under <link en news images_video_audio image_galleries polarstern_in_the_arctic>www.awi.de/en/news/images_video_audio/image_galleries/polarstern_in_the_arctic/.

Your contact persons at the Alfred Wegener Institute are Dr. Ingo Schewe (tel.: +49 471 483-1737, e-mail: Ingo.Schewe@awi.de) and Dr. Benjamin Rabe (tel.: +49 471 4831-2403, e-mail: Benjamin.Rabe@awi.de). Your contact person in the Dept. of Communications and Media Relations is Dr. Folke Mehrtens (tel.: +49 471 4831-2007; e-mail: Folke.Mehrtens@awi.de).

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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 Antarctica. The Alfred Wegener Institute is one of the 18 research centres of the Helmholtz Association, the largest scientific organisation in Germany.