North Atlantic surface-ocean control of Pleistocene deep-ocean circulation
نویسندگان
چکیده
Deep basins of the North Atlantic were occupied by a cold 13 C-depleted (nutrient-rich) water mass during glaciations, and a warmer 13C-enriched (nutrient-poor) water mass (modern NADW) during interglaciations. This mode of deep-water variability is related directly to migration of the North Atlantic Polar Front. Down-core stable isotope records from the Atlantic and Antarctic suggest that 13C depletion of the glacial North Atlantic may reflect higher preformed nutrients (due to bottom-water formation under sea and/or shelf ice) and increased residence time of northern-source water, rather than replacement of N A D W with AABW.
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