Impact of North Atlantic – GIN Sea exchange on deglaciation evolution of the Atlantic Meridional Overturning Circulation

摘要

In a transient simulation of the last deglaciation with a fully coupledmodel (TraCE-21000), an overshoot of the Atlantic Meridional OverturningCirculation (AMOC) is simulated and proposed as a key factor for the onsetof the B?lling-Aller?d (BA) warming event. There is collaboratingevidence for an AMOC overshoot at the BA in various proxy reconstructionsalthough the mechanism governing its behavior is not well understood. Here,we present two new sensitivity experiments to explicitly illustrate theimpact of North Atlantic – GIN Sea exchange on the AMOC's deglacialevolution. Results show that this oceanic exchange dominates the convectionrestarting in the GIN Sea, the occurrence of the AMOC overshoot, and thefull BA warming.