The stability of Antarctic ice sheets and their potential contribution to sea level under projected future warming remains highly uncertain. The Last Interglacial (135 000-116 000 years ago) provides a potential analogue, with global temperatures 2°C higher and rates of sea-level rise >5.6m ka-1, leading to sea levels 6.6-9.4m higher than present. The source(s) of this sea-level rise remain fiercely debated. Here we report a series of independent model simulations exploring the effects of migrating Southern Hemisphere Westerlies (SHWs) on Southern Ocean circulation and Antarctic ice-sheet dynamics. We suggest that southerly shifts in winds may have significantly impacted the sub-polar gyres, inducing pervasive warming (0.2-0.8°C in the upper 1200m) adjacent to sectors of the East Antarctic Ice Sheet (EAIS), which due to their geometries and connectivity to the Southern Ocean are highly sensitive to ocean forcing. We conclude that the EAIS potentially made a substantial, hitherto unsuspected, contribution to interglacial sea levels, and given 21st-century projections in the Southern Annular Mode and associated SHW migration, we highlight how pervasive circum-Antarctic warming may threaten EAIS stability. © 2013 John Wiley & Sons, Ltd.

Item Type:	Refereed Article
Keywords:	East Antarctic Ice Sheet; Last Interglacial; Southern Annular Mode; Southern Hemisphere Westerlies; Southern Ocean
Research Division:	Earth Sciences
Research Group:	Oceanography
Research Field:	Physical Oceanography
Objective Division:	Environment
Objective Group:	Climate and Climate Change
Objective Field:	Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts)
Author:	Roberts, JL (Dr Jason Roberts)
ID Code:	93946
Year Published:	2014
Web of Science® Times Cited:	13
Deposited By:	CRC-Antarctic Climate & Ecosystems
Deposited On:	2014-08-25
Last Modified:	2015-02-24
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