Abstract

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 BøllingeAllerød 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.