A topographic hinge-zone divides coastal and inland ice dynamic regimes in East Antarctica

Andersen, J. L. et al. (2023) A topographic hinge-zone divides coastal and inland ice dynamic regimes in East Antarctica. Communications Earth and Environment, 4(1), 9. (doi: 10.1038/s43247-022-00673-6)

Abstract

The impact of late Cenozoic climate on the East Antarctic Ice Sheet is uncertain. Poorly constrained patterns of relative ice thinning and thickening impair the reconstruction of past ice-sheet dynamics and global sea-level budgets. Here we quantify long-term ice cover of mountains protruding the ice-sheet surface in western Dronning Maud Land, using cosmogenic Chlorine-36, Aluminium-26, Beryllium-10, and Neon-21 from bedrock in an inverse modeling approach. We find that near-coastal sites experienced ice burial up to 75–97% of time since 1 Ma, while interior sites only experienced brief periods of ice burial, generally <20% of time since 1 Ma. Based on these results, we suggest that the escarpment in Dronning Maud Land acts as a hinge-zone, where ice-dynamic changes driven by grounding-line migration are attenuated inland from the coastal portions of the East Antarctic Ice Sheet, and where precipitation-controlled ice-thickness variations on the polar plateau taper off towards the coast.

• Item Type: Articles
• Additional Information: Open access funding provided by Stockholm University. This material is based upon work supported by Stockholm University (A.P.S.), Norwegian Polar Institute/NARE under Grant “MAGIC-DML” (O.F.), the US National Science Foundation under Grant No. PLR-1542930 (N.L. & J.M.H.) and EAR-1560658 (M.W.C.), Swedish Research Council under Grant No. 2016-04422 (J.M.H. & A.P.S.). J.L.A. was supported by a Carlsberg Foundation Fellowship and a Wenner-Gren Foundations stipend. VKP was supported by Villum Fonden (Grant no. 15467).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fabel, Dr Derek and Stuart, Professor Fin
• Authors: Andersen, J. L., Newall, J. C., Fredin, O., Glasser, N. F., Lifton, N. A., Stuart, F. M., Fabel, D., Caffee, M., Pedersen, V. K., Koester, A. J., Suganuma, Y., Harbor, J. M., and Stroeven, A. P.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Communications Earth and Environment
• Publisher: Nature Research
• ISSN: 2662-4435
• ISSN (Online): 2662-4435
• Copyright Holders: Copyright © 2023 IEEE
• First Published: First published in Communications Earth and Environment 4(1):9
• Publisher Policy: Reproduced under a Creative Commons License