The triggers of the disaggregation of Voyeykov Ice Shelf (2007), Wilkes Land, East Antarctica, and its subsequent evolution

Abstract The weakening and/or removal of floating ice shelves in Antarctica can induce inland ice flow acceleration. Numerical modelling suggests these processes will play an important role in Antarctica's future sea-level contribution, but our understanding of the mechanisms that lead to ice t...

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Bibliographic Details
Published in:Journal of Glaciology
Main Authors: Arthur, Jennifer F., Stokes, Chris R., Jamieson, Stewart S. R., Miles, Bertie W. J., Carr, J. Rachel, Leeson, Amber A.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2021
Subjects:
Online Access:http://dx.doi.org/10.1017/jog.2021.45
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000459
Description
Summary:Abstract The weakening and/or removal of floating ice shelves in Antarctica can induce inland ice flow acceleration. Numerical modelling suggests these processes will play an important role in Antarctica's future sea-level contribution, but our understanding of the mechanisms that lead to ice tongue/shelf collapse is incomplete and largely based on observations from the Antarctic Peninsula and West Antarctica. Here, we use remote sensing of structural glaciology and ice velocity from 2001 to 2020 and analyse potential ocean-climate forcings to identify mechanisms that triggered the rapid disintegration of ~2445 km 2 of ice mélange and part of the Voyeykov Ice Shelf in Wilkes Land, East Antarctica between 27 March and 28 May 2007. Results show disaggregation was pre-conditioned by weakening of the ice tongue's structural integrity and was triggered by mélange removal driven by a regional atmospheric circulation anomaly and a less extensive latent-heat polynya. Disaggregation did not induce inland ice flow acceleration, but our observations highlight an important mechanism through which floating termini can be removed, whereby the break-out of mélange and multiyear landfast sea ice triggers disaggregation of a structurally-weak ice shelf. These observations highlight the need for numerical ice-sheet models to account for interactions between sea-ice, mélange and ice shelves.