The diatom flora in the Fram Strait. A comparison with the Pleistocene/Holocene boundary flora in the Norwegian Sea

Abstract

High abundances of diatoms were recorded near the Pleistocene/Holocene boundary in sediment cores from the Norwegian-Greenland Sea (Stabell 1986 and references therein). Diatom maxima of similar age were recently reported from the northeast Norwegian Sea (Pedersen 1987). Stabell (1986) suggested that the diatom maxima reflect the passage of the Subarctic Convergence (oceanic polar front) which moved from the southern North Atlantic (about 45"N) at about l8.000B.P. (glacial maximum) to its present position south and east of Greenland (Ruddiman & Mclntyre 1981). The northward movement of the polar front resulted in cold Arctic water being replaced by warm, saline Atlantic water of the North Atlantic Current. Mixing of polar and subpolar Atlantic surface water masses was expected by our models to result in more nutrient-enriched surface water and thereby increased diatom productivity.