TY - JOUR

T1 - Bedrock Erosion Surfaces Record Former East Antarctic Ice Sheet Extent

AU - Paxman, Guy J.G.

AU - Jamieson, Stewart S.R.

AU - Ferraccioli, Fausto

AU - Bentley, Michael J.

AU - Ross, Neil

AU - Armadillo, Egidio

AU - Gasson, Edward G.W.

AU - Leitchenkov, German

AU - DeConto, Robert M.

PY - 2018/4/27

Y1 - 2018/4/27

N2 - East Antarctica hosts large subglacial basins into which the East Antarctic Ice Sheet (EAIS) likely retreated during past warmer climates. However, the extent of retreat remains poorly constrained, making quantifying past and predicted future contributions to global sea level rise from these marine basins challenging. Geomorphological analysis and flexural modeling within the Wilkes Subglacial Basin are used to reconstruct the ice margin during warm intervals of the Oligocene-Miocene. Flat-lying bedrock plateaus are indicative of an ice sheet margin positioned >400–500 km inland of the modern grounding zone for extended periods of the Oligocene-Miocene, equivalent to a 2-m rise in global sea level. Our findings imply that if major EAIS retreat occurs in the future, isostatic rebound will enable the plateau surfaces to act as seeding points for extensive ice rises, thus limiting extensive ice margin retreat of the scale seen during the early EAIS.

AB - East Antarctica hosts large subglacial basins into which the East Antarctic Ice Sheet (EAIS) likely retreated during past warmer climates. However, the extent of retreat remains poorly constrained, making quantifying past and predicted future contributions to global sea level rise from these marine basins challenging. Geomorphological analysis and flexural modeling within the Wilkes Subglacial Basin are used to reconstruct the ice margin during warm intervals of the Oligocene-Miocene. Flat-lying bedrock plateaus are indicative of an ice sheet margin positioned >400–500 km inland of the modern grounding zone for extended periods of the Oligocene-Miocene, equivalent to a 2-m rise in global sea level. Our findings imply that if major EAIS retreat occurs in the future, isostatic rebound will enable the plateau surfaces to act as seeding points for extensive ice rises, thus limiting extensive ice margin retreat of the scale seen during the early EAIS.

UR - http://www.scopus.com/inward/record.url?scp=85046625415&partnerID=8YFLogxK

U2 - 10.1029/2018GL077268

DO - 10.1029/2018GL077268

M3 - Article

AN - SCOPUS:85046625415

VL - 45

SP - 4114

EP - 4123

JO - Geophysical Research Letters

JF - Geophysical Research Letters

SN - 0094-8276

IS - 9

ER -