title: Contribution of Antarctica to past and future sea-level rise.
abstract: Polar temperatures over the last several million years have, at times, been slightly warmer than today, yet global mean sea level has been 6-9 metres higher as recently as the Last Interglacial (130,000 to 115,000 years ago) and possibly higher during the Pliocene epoch (about three million years ago). In both cases the Antarctic ice sheet has been implicated as the primary contributor, hinting at its future vulnerability. Here we use a model coupling ice sheet and climate dynamics-including previously underappreciated processes linking atmospheric warming with hydrofracturing of buttressing ice shelves and structural collapse of marine-terminating ice cliffs-that is calibrated against Pliocene and Last Interglacial sea-level estimates and applied to future greenhouse gas emission scenarios. Antarctica has the potential to contribute more than a metre of sea-level rise by 2100 and more than 15 metres by 2500, if emissions continue unabated. In this case atmospheric warming will soon become the dominant driver of ice loss, but prolonged ocean warming will delay its recovery for thousands of years.
authors.affiliation: Department of Geosciences, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Robert M
authors.initials: RM
authors.lastname: DeConto
authors.affiliation: Earth and Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: David
authors.initials: D
authors.lastname: Pollard
mesh_terms: D000864:Antarctic Regions; D001272:Atmosphere; D002138:Calibration; D057231:Climate Change / Q000706:statistics & numerical data*; D017752:Greenhouse Effect / Q000706:statistics & numerical data; D046448:Ice Cover; D008962:Models, Theoretical; D012623:Seawater / Q000032:analysis*; D013696:Temperature; D013997:Time Factors; D014872:Water Movements