The importance of deep and bottom water formed in the Southern Ocean to the ventilation of theworld ocean abyss has been accepted by the oceanographic community. Uncertainties, however,exist about rate and exact location of dense water mass sinking around Antarctica. Based on watermass analysis, the Weddell Sea in the Atlantic sector has long been identified as being the majorsource for bottom water. The contribution of the Ross Sea in the western Pacific sector, althoughwith similar if not more favorable ingredients for dense bottom water formation, seemed to be minor.Observations and recent tracer analysis indicate that the Indian-Pacific sector might host sourceswhich together can compete with their Atlantic counterpart. Our numerical model results support asplitting of the Atlantic and Indian-Pacific contributions into roughly equal parts but for bottomwaters of different density. The observationally derived formation rate for dense Antarctic BottomWater on the order of 10 Sv (1 Sv = 10^6 m^3/s) is confirmed but doubles if the lighter componentof the Indian-Pacific sector is included. This places southern and northern hemisphere sources asequal contributors to the ventilation of the world ocean.
AWI Organizations > Climate Sciences > Climate Dynamics
AWI Organizations > Climate Sciences > Sea Ice Physics