Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions
The onset of sliding in ice sheets may not take the form of a sharp boundary between regions at the melting point, in which sliding is permitted, and regions below that temperature, in which there is no slip. Such a hard switch leads to the paradox of the bed naturally wanting to refreeze as soon as...
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crroyalsociety:10.1098/rspa.2019.0411 2024-09-15T18:12:14+00:00 Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions Mantelli, E. Schoof, C. NSERC 2019 http://dx.doi.org/10.1098/rspa.2019.0411 https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.2019.0411 https://royalsocietypublishing.org/doi/full-xml/10.1098/rspa.2019.0411 en eng The Royal Society https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences volume 475, issue 2231, page 20190411 ISSN 1364-5021 1471-2946 journal-article 2019 crroyalsociety https://doi.org/10.1098/rspa.2019.0411 2024-06-24T04:28:29Z The onset of sliding in ice sheets may not take the form of a sharp boundary between regions at the melting point, in which sliding is permitted, and regions below that temperature, in which there is no slip. Such a hard switch leads to the paradox of the bed naturally wanting to refreeze as soon as sliding has commenced. A potential alternative structure is a region of subtemperate sliding. Here temperatures are marginally below the melting point and sliding velocities slower than they would if the bed was fully temperate. Rather than being controlled by a standard sliding law, sliding velocities are then constrained by the need to maintain energy balance. This thermal structure arises in temperature-dependent sliding laws in the limit of strong sensitivity to temperature. Here, we analyse the stability of such subtemperate regions, showing that they are subject to a set of instabilities that occur at all length scales between ice thickness and ice sheet length. The fate of these instabilities is to cause the formation of patches of frozen bed, raising the possibility of highly complicated cold-to-temperate transitions with spatial structures at short length scales that cannot be resolved in large-scale ice sheet simulation codes. Article in Journal/Newspaper Ice Sheet The Royal Society Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475 2231 20190411 |
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The Royal Society |
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crroyalsociety |
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English |
description |
The onset of sliding in ice sheets may not take the form of a sharp boundary between regions at the melting point, in which sliding is permitted, and regions below that temperature, in which there is no slip. Such a hard switch leads to the paradox of the bed naturally wanting to refreeze as soon as sliding has commenced. A potential alternative structure is a region of subtemperate sliding. Here temperatures are marginally below the melting point and sliding velocities slower than they would if the bed was fully temperate. Rather than being controlled by a standard sliding law, sliding velocities are then constrained by the need to maintain energy balance. This thermal structure arises in temperature-dependent sliding laws in the limit of strong sensitivity to temperature. Here, we analyse the stability of such subtemperate regions, showing that they are subject to a set of instabilities that occur at all length scales between ice thickness and ice sheet length. The fate of these instabilities is to cause the formation of patches of frozen bed, raising the possibility of highly complicated cold-to-temperate transitions with spatial structures at short length scales that cannot be resolved in large-scale ice sheet simulation codes. |
author2 |
NSERC |
format |
Article in Journal/Newspaper |
author |
Mantelli, E. Schoof, C. |
spellingShingle |
Mantelli, E. Schoof, C. Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions |
author_facet |
Mantelli, E. Schoof, C. |
author_sort |
Mantelli, E. |
title |
Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions |
title_short |
Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions |
title_full |
Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions |
title_fullStr |
Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions |
title_full_unstemmed |
Ice sheet flow with thermally activated sliding. Part 2: the stability of subtemperate regions |
title_sort |
ice sheet flow with thermally activated sliding. part 2: the stability of subtemperate regions |
publisher |
The Royal Society |
publishDate |
2019 |
url |
http://dx.doi.org/10.1098/rspa.2019.0411 https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.2019.0411 https://royalsocietypublishing.org/doi/full-xml/10.1098/rspa.2019.0411 |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences volume 475, issue 2231, page 20190411 ISSN 1364-5021 1471-2946 |
op_rights |
https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ |
op_doi |
https://doi.org/10.1098/rspa.2019.0411 |
container_title |
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences |
container_volume |
475 |
container_issue |
2231 |
container_start_page |
20190411 |
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1810449827317678080 |