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Timing of Fluxes in the Nordic Seas

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Timing of Fluxes in the Nordic Seas Timing of fluxes in the Nordic seas Svend-Aage Malmberg Marine Research Institute, P.O.Box 1290, 121 Reykjavik, Iceland The large-scale near-surface circulation in the Nordic seas is dominated by the warm northward flowing Atlantic inflow, mainly on the eastern side, and the cold East Greenland Current flowing southwards on the western side. Atlantic water enters the Norwegian Sea mainly through the Faroe- Shetland Channel along the Scottish slope feeding the eastern branch of the Norwegian Atlantic Current, and between the Faroes and Iceland feeding the Faroe Current which flows further into the Norwegian Sea as a western branch of the Norwegian Atlantic Current. Some Atlantic water from the south is also carried into the Iceland Sea through the Denmark Strait by the North Icelandic branch of the Irminger Current. In the north off Spitsbergen the Atlantic water of the eastern branch of the Norwegian Current, named West Spitsbergen Current, devides into a branch flowing into the Arctic Ocean and another one recirculating counterclockwise into the southward flowing East Greenland Current. Together with the main southward flowing branch of the East Greenland Current it also branches off counterclockwise to the east firstly as Jan Mayen Polar Current, which brings the waters into a cyclanic circulation in the Greenland Sea, and secondly and further south as the East Icelandic Current flowing eastwards into the Iceland and Norwegian Seas. Thus in general, the circulation in the upper layers of the Nordic Seas is fed by the warm Atlantic water from the south and the cold Polar water from the north, a circulation steered by the topographic features into cyclonic circulation's, both overall in the Nordic Seas and regionally in the separated Norwegian, Greenland and Iceland Seas or Basins. Contaminants in the waters from Western Europe reach the eastern areas of the Nordic Seas from the south and the western areas from the north by the cyclanic current systems. The timing of this pathway from the North Sea area and around the Nordic Seas into North Icelandic waters was according to time-series on salinity as well as radionuclides in the 1970's and 1980's 4-5 years. Ongoing research on the fate of the recent technicium - 99 release in the latter half of the 1990's may reveal its appearance in North Icelandic waters in present or near-by times. References Blindheim, J., Borovkov, V., Hansen, B., Malmberg, S.A., Turnell, W.R., Osterhus, S. 1999. The upper layer cooling and freshening in the Norwegian Sea in relation to atmospheric forcing. Deep- Sea Research 1, 47, 655-680. Belkin, I.M., Levitus, S.,., Antonov, I., Malmberg, S.A. 1998. "Great Salinity Anomalies" in the North Atlantic. Progress in Oceanography 41, 1-18. Dahlgaard, H. 1994. Sources of Cs-137, Sr-90 and Tc-99 in the East Greenland Current. J. Environ. Radioactively 25, 37-55. Dickson, R.R., Meincke, J., Malmberg, S.A., Lee, A. 1988. "The Great Salinity Anomaly" in the northern North Atlantic, 1968-1982. Progress in Oceanography 20, 2, 103-151. 200 Hansen B. and østurhus S. 2000. North Atlantic-Nordic Seas exchanges. Progress in Oceanography 45, 2, 109-208. Olafsdottir, D.E., Pålsson, S.E., Magnusson, S.E., Gudnason, K. 1999. Distribution and origin of Cs-137 in the ocean around Iceland - an indicator of man-made radioactivety. Rit Fiskideildar 16, 79-88. Poulain, P.M., Wam-Warnas, A., Niiler, P.P. 1996. Near-surface circulation of the Nordic Seas as measured by Lagnangian drifters. Journ. of Geophysical Research 101, C8, 19237-19258. 201.
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