Ice loss from the East Antarctic Ice Sheet during late Pleistocene interglacials

• Published in: Nature
• Main Authors: Wilson, David J., Bertram, Raquel A., Needham, Emma F., van de Flierdt, Tina, Welsh, Kevin J., McKay, Robert M., Mazumder, Anannya, Riesselman, Christina R., Jimenez Espejo, Francisco Jose, Escutia, Carlota
• Other Authors: International Continental Scientific Drilling Program, National Science Foundation (US), Australian Research Council, Ministerio de Ciencia e Innovación (España)
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Nature Publishing Group 2018
• Subjects: Antarctic Regions; Geologic Sediments; Global Warming; History; Ancient; Hot Temperature; Ice Cover; Seawater; Antarc*; Antarctic; Antarctica; East Antarctica; Ice Sheet
• Online Access: http://hdl.handle.net/10261/361104; https://doi.org/10.1038/s41586-018-0501-8

Understanding ice sheet behaviour in the geological past is essential for evaluating the role of the cryosphere in the climate system and for projecting rates and magnitudes of sea level rise in future warming scenarios. Although both geological data and ice sheet models indicate that marine-based sectors of the East Antarctic Ice Sheet were unstable during Pliocene warm intervals, the ice sheet dynamics during late Pleistocene interglacial intervals are highly uncertain. Here we provide evidence from marine sedimentological and geochemical records for ice margin retreat or thinning in the vicinity of the Wilkes Subglacial Basin of East Antarctica during warm late Pleistocene interglacial intervals. The most extreme changes in sediment provenance, recording changes in the locus of glacial erosion, occurred during marine isotope stages 5, 9, and 11, when Antarctic air temperatures were at least two degrees Celsius warmer than pre-industrial temperatures for 2,500 years or more. Hence, our study indicates a close link between extended Antarctic warmth and ice loss from the Wilkes Subglacial Basin, providing ice-proximal data to support a contribution to sea level from a reduced East Antarctic Ice Sheet during warm interglacial intervals. While the behaviour of other regions of the East Antarctic Ice Sheet remains to be assessed, it appears that modest future warming may be sufficient to cause ice loss from the Wilkes Subglacial Basin. Acknowledgements This research used samples and data provided by Integrated Ocean Drilling Program (IODP) Expedition 318, sponsored by the US National Science Foundation (NSF) and participating countries under the management of the Consortium for Ocean Leadership. D.J.W. thanks B. Coles, C. Huck, K. Kreissig, N. Pratt and P. Simoes Pereira for technical support. D.J.W., R.A.B., E.F.N. and T.v.d.F. acknowledge financial support from the Kristian Gerhard Jebsen Foundation, the Leverhulme Trust (RPG-398) and NERC (NE/N001141/1, NE/H025162/1). K.J.W. and R.M.M. were funded by the ...