Expression of the bipolar see-saw in Antarctic climate records during the last deglaciation

Ice-core records of climate from Greenland and Antarctica show asynchronous temperature variations on millennial timescales during the last glacial period 1 . The warming during the transition from glacial to interglacial conditions was markedly different between the hemispheres, a pattern attributed to the thermal bipolar see-saw 2 . However, a record from the Ross Sea sector of East Antarctica has been suggested to be synchronous with Northern Hemisphere climate change 3 . Here we present a temperature record from the Talos Dome ice core, also located in the Ross Sea sector. We compare our record with ice-core analyses from Greenland, based on methane synchronization 4 , and find clearly asynchronous temperature changes during the deglaciation. We also find distinct differences in Antarctic records, pointing to differences in the climate evolution of the Indo-Pacific and Atlantic sectors of Antarctica. In the Atlantic sector, we find that the rate of warming slowed between 16,000 and 14,500 years ago, parallel with the deceleration of the rise in atmospheric carbon dioxide concentrations and with a slight cooling over Greenland. In addition, our chronology supports the hypothesis that the cooling of the Antarctic Cold Reversal is synchronous with the Bolling‐Allerod warming in the northern hemisphere 14,700 years ago 5 . The period from about 8 to 25kyr before present (bp) includes the climate transition from the last glacial to the Holocene. As documented from polar ice cores and other climate archives, the pattern of climate changes throughout this transition is different between Antarctica and the surrounding Southern Ocean and the Northern Hemisphere. The steady Antarctic deglacial warming reaches a first maximum (Antarctic Isotopic Maximum AIM1; ref.1)followedbyaninterruptiontowardscoolerconditionsduring the Antarctic Cold Reversal (ACR). Conversely, Greenland records show two rapid-warming phases at the onset of the Dansgaard Oeschger-1(DO1)event(BllingAller dinterstadial,B/A)andthe