Open AccessPromotion of meridional overturning by Mediterranean‐derived salt during the last deglaciation
Author(s) -
Rogerson M.,
Rohling E. J.,
Weaver P. P. E
Publication year - 2006
Publication title -
paleoceanography
Language(s) - English
Resource type - Journals
eISSN - 1944-9186
pISSN - 0883-8305
DOI - 10.1029/2006pa001306
Subject(s) - deglaciation , geology , mediterranean climate , oceanography , salinity , outflow , thermohaline circulation , shutdown of thermohaline circulation , north atlantic deep water , climatology , holocene , geography , archaeology
We demonstrate that changes in the behavior of the Mediterranean Outflow Water (MOW) prior to and through the last deglaciation played an important role in promoting Meridional Overturning Circulation (MOC). Estimation of past MOW salt and heat fluxes indicates that they gradually increased through the last deglaciation. Between 17.5 and 14.6 thousand years ago (ka B.P., where B.P. references year 1950), net evaporation from the Mediterranean exported sufficient fresh water from the North Atlantic catchment to cause an average salinity increase of 0.5 psu throughout the upper 2000 m of the entire North Atlantic to the north of 25°N. Combined with rapid intensification and shoaling of the MOW plume, which we identify around 15–14.5 ka B.P., this deglacial MOW‐related salt accumulation preconditioned the North Atlantic for abrupt resumption of the MOC at 14.6 ka B.P.