Science cruising the Arctic sea
“The research vessel Polarstern left Bremerhaven on 16. June and will be going north along the Norwegian coast for about a month,” says Katrine Aspmo, a scientists who works specially with environmental chemistry at the Norwegian Institute for Air Research (NILU).
Polarstern, the most important tool in Germany’s polar research programmes, is a research and supply vessel. Polarstern has completed a total of 27 expeditions to the Arctic and Antarctic since the ship was first commissioned in 1982. The ship was specially designed for working in the polar seas and is currently the most sophisticated polar research vessel in the world.
“The first destination is Longyearbyen, the largest community on Svalbard, where NILU will join the vessel on 16. July. Polarstern will then be cruising around the Greenland Sea and as far north its possible to sail before the voyage ends in the city Tromsø at the end of August. It’s totally of six weeks to sea”, says Aspmo.
The scientists common interest on the cruise is the detection of trace organic contaminations and mercury species in the rare environments of the Arctic and to investigate the environmental cycling and fate of key global pollutants.
Several environmental issues will be studied during the research voyage. One of the topics for NILU is to investigate how much mercury can be re-emitted into the atmosphere by reduction processes. Measurements in snow and flux experiments have shown that this process plays a key role before and after the snow melting in Arctic regions.
During the Arctic and Antarctic spring gaseous mercury exhibit unexpected strong concentration decreases. This phenomenon is called ‘Atmospheric Mercury Depletion Event’ (AMDE), and is considered important for the pollution of polar regions. The gaseous mercury is converted to other mercury species that can be quickly removed from the atmosphere by deposition. Once deposited, the converted mercury can be transformed back to it`s gaseous form and re-emitted back to the atmosphere or mercury can enter the ecosystem through melting water.
The international study on board of Polarstern with the transect from Germany to the North Atlantic should help to investigate the temporal end of AMDEs during Artic summer and the spatial distribution of the relevant areas in the north Atlantic Ocean. The fate of mercury during polar summer in the Arctic should be analysed with several different methods for the detection of mercury species in air, water, snow, and ice.
Research at sea
The Polarstern with her conditions has been found to be well suited to act as a ‘clean ship’ for the sampling of these trace compounds. The ship is equipped for biological, geological, geophysical, glaciological, chemical, oceanographic and meteorological research, and contains nine research laboratories. Refrigerated rooms and aquaria permit the transport of samples and living marine fauna.
The Polarstern has a crew of at most 44, and offers work facilities for 50 scientists and technicians. It was specially designed for working in the polar seas and is currently the most sophisticated polar research vessel in the world. The computer system on board continuously captures and stores meteorological, oceanographic and other data as required.