Changing influence of Antarctic and Greenlandic temperature records on sea-level over the last glacial cycle

We use a simple model to analyse the relationship between ice core temperature proxy data and global ice volume/eustatic sea-level data over the last glacial cycle (LGC). By allowing the temperature forcing to be a mix of Greenlandic and Antarctic signals we optimise the proportion of this mixing to fit sea-level data. We find that sea-level forcing is best represented by a mix of Antarctic and Greenlandic temperature signals through the whole glacial cycle. We suggest that a distinct bipolar switch occurs which links eustatic sea-level more closely with the Antarctic-like variability during the glacial period (MIS 4, 3 and 2) and more closely to the Greenland-like variability during the last termination (TI) and the interglacial periods (Holocene and MIS 5). This switch may be caused by the spatio-temporal distribution of ice sheet collapse perhaps linked to glacial to interglacial changes in deep water distribution in the ocean, which in turn drive changes in pole-ward heat and moisture transport. (C) 2009 Elsevier Ltd. All rights reserved.