| Summary: | Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies 1,2 have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard - Oeschger events in Greenland 3-5 through the Atlantic meridional overturning circulation 6-8 . It has been unclear, however, whether the shorter Dansgaard - Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland 9 , the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard - Oeschger events by the bipolar seesaw 6 . The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.
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