For 17 years, scientists from the deep-sea observatory, AWI-HAUSGARTEN west of the island of Spitsbergen, have been conducting long-term oceanographic studies at 78.8° north in the Fram Strait. For 15 years AWI-HAUSGARTEN has been operated by the Alfred Wegner Institute, Helmholtz Centre for Polar and Marine Research (AWI). They are attempting 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 Strait.
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. But they are mnboiw turning theior 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 metres. From these stations they intend 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. The expedition is planned to end on 3 July in the Norwegian port of Tromsø.
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 additional moorings are being placed on the East Greenland Shelf. 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.
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.
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.
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