The Roles of Orbital and Meltwater Climate Forcings on the Southern Ocean Dynamics during the Last Deglaciation

The last deglacial climate evolution, from 19 to 9 thousand years before the present, represents vital role of feedback in Earth’s system. Southern Ocean played a fundamental by exchanging nutrients and carbon-rich deep ocean water with surface during deglaciation. This study employs fully coupled Earth system model investigate evolution dynamics roles changes orbital meltwater forcings simulation supports that upwelling was primarily driven windstress. results show melting formation Antarctic sea ice influenced buoyancy flux. increase melt-induced freshwater flux resulted steepened north-south salinity gradient Ocean, which enhanced upwelling. single-forcing experiments indicate insolation also highlight dominant Northern Hemisphere discharge upper lower branch Meridional Overturning Circulation. Furthermore, forcing shows lesser retreat than forcing, follows bipolar seesaw mechanism.