DEEP-WATER FORMATION AND EXCHANGE-RATES IN THE GREENLAND NORWEGIAN SEAS AND THE EURASIAN BASIN OF THE ARCTIC-OCEAN DERIVED FROM TRACER BALANCES

Multi-tracer data sets collected in the Greenland/Norwegian seas and t he Eurasian Basin of the Arctic Ocean in the 1970s and 1980s are used, together with temperature and salinity, to (1) constrain box model ca lculations of the deep water formation rates in the Greenland Sea and the Eurasian Basin of the Arctic Ocean, and (2) estimate the exchange rates of deep waters (depth less-than-or-equal-to 1,500m) between the Greenland/Norwegian Seas and the Eurasian Basin. We obtain deep water formation rates of 0.1 Sv (since 1980) to 0.47Sv (from at least 1965 t o 1980) for the Greenland Sea, and 0.3Sv for the Eurasian Basin of the Arctic Ocean. The southward flux of Eurasian Basin Deep Water through Fram Strait is estimated to be about 1 Sv. About 0.12Sv of this flux are transported into the Greenland Sea, about 0.37Sv reach the deep No rwegian Sea through the Jan Mayen Fracture Zone, and about 0.39Sv leav e the Arctic Ocean through a shallower core which more or less directl y feeds into the Iceland Sea, and, after modification, eventually ends up in the overflow waters. The outflow of Eurasian Basin Deep Water i s balanced by deep water formation in the Arctic Ocean and by inflow o f Norwegian Sea Deep water. About 0.77Sv of deep water formed in the G reenland Sea and the Eurasian Basin contribute to the formation of Nor th Atlantic Deep Water. Uncertainties of the fluxes are estimated to b e roughly +/-20 to 30%.