Northward shift of the southern westerlies during the Antarctic Cold Reversal

Inter-hemispheric asynchrony of climate change through the last deglaciation has been theoretically linked to latitudinal shifts in the southern westerlies via their influence over CO2 out-gassing from the Southern Ocean. Proxy-based reconstructions disagree on the behaviour of the westerlies through this interval. The last deglaciation was interrupted in the Southern Hemisphere by the Antarctic Cold Reversal (ACR; 14.7 to 13.0 ka BP (thousand years Before Present)), a millennial-scale cooling event that coincided with the Bolling-Allerod warm phase in the North Atlantic (BA; 14.7 to 12.7 ka BP). We present terrestrial proxy palaeoclimate data that demonstrate a migration of the westerlies during the last deglaciation. We support the hypothesis that wind-driven out-gassing of old CO2 from the Southern Ocean drove the deglacial rise in atmospheric CO2. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Climate change during the last deglaciation was potentially influenced by the southern westerlies' latitudinal shifts, affecting CO2 out-gassing from the Southern Ocean. The last deglaciation in the Southern Hemisphere was interrupted by a cooling event, coinciding with a warm phase in the North Atlantic. Research shows a migration of the westerlies during the last deglaciation, driving the rise in atmospheric CO2.