This project is an examination of the geochemistry of naturally occurring trace elements in the Arctic Ocean. The primary trace element is aluminum, but measurements of iron, beryllium, and selenium will also be made. The objective is to determine the magnitude, variability, and source of aluminum enrichment of the shelf brines in the Barents, Kara, and Laptev Seas, and to use these results to infer hydrographic processes of the eastern Arctic Ocean. The Norwegian and Greenland Seas have a dissolved aluminum concentration that is considerably higher than expected from the exchange of water masses, pointing to a regional external source of aluminum. While the normal pathways are the dissolution of aluminum carried through the atmosphere and deposited at the surface, and through river discharge, an additional arctic pathway is by fractionation in the freezing process. That is, sea ice is depleted and the resulting brine is enriched in aluminum. The measurements will be made on a Summer 1993 cruise of the German polar research vessel POLARSTERN as part of a wide-ranging physical and chemical observing program. An exceptional framework of hydrographic data will be available for the interpretation and analysis of these geochemical measurements.
