Stability of ice-sheet grounding lines
Recent observations of the West Antarctic Ice Sheet document rapid changes in the mass balance of its component glaciers. These observations raise the question of whether changing climatic conditions have triggered a dynamical instability in the ice-sheet-iceshelf system. The dynamics of marine ice...
Published in: | Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences |
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ftuloxford:oai:ora.ox.ac.uk:uuid:5fd4f7f7-b68b-45e6-9f97-b30dd8c24252 2024-09-30T14:22:57+00:00 Stability of ice-sheet grounding lines Katz, R Worster, MG 2016-07-28 https://doi.org/10.1098/rspa.2009.0434 https://ora.ox.ac.uk/objects/uuid:5fd4f7f7-b68b-45e6-9f97-b30dd8c24252 eng eng doi:10.1098/rspa.2009.0434 https://ora.ox.ac.uk/objects/uuid:5fd4f7f7-b68b-45e6-9f97-b30dd8c24252 https://doi.org/10.1098/rspa.2009.0434 info:eu-repo/semantics/embargoedAccess Journal article 2016 ftuloxford https://doi.org/10.1098/rspa.2009.0434 2024-09-06T07:47:34Z Recent observations of the West Antarctic Ice Sheet document rapid changes in the mass balance of its component glaciers. These observations raise the question of whether changing climatic conditions have triggered a dynamical instability in the ice-sheet-iceshelf system. The dynamics of marine ice sheets are sensitive to grounding-line position and variation, characteristics that are poorly captured by most current models. We present a theory for grounding-line dynamics in three spatial dimensions and time. Our theory is based on a balance of forces across the grounding line; it is expressed as a differential equation that is analogous to the canonical Stefan condition. We apply this theory to the question of grounding-line stability under conditions of retrograde bed slope in a suite of calculations with different basal topography. A subset of these have basal topography inspired by the Pine Island glacier, where basal depth varies in both the along-flow and across-flow directions. Our results indicate that unstable retreat of the grounding line over retrograde beds is a robust feature of models that evolve based on force balance at the grounding line. We conclude, based on our simplified model, that unstable grounding-line recession may already be occurring at the Pine Island glacier. © 2010 The Royal Society. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Pine Island Glacier ORA - Oxford University Research Archive Antarctic Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) West Antarctic Ice Sheet Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 466 2118 1597 1620 |
institution |
Open Polar |
collection |
ORA - Oxford University Research Archive |
op_collection_id |
ftuloxford |
language |
English |
description |
Recent observations of the West Antarctic Ice Sheet document rapid changes in the mass balance of its component glaciers. These observations raise the question of whether changing climatic conditions have triggered a dynamical instability in the ice-sheet-iceshelf system. The dynamics of marine ice sheets are sensitive to grounding-line position and variation, characteristics that are poorly captured by most current models. We present a theory for grounding-line dynamics in three spatial dimensions and time. Our theory is based on a balance of forces across the grounding line; it is expressed as a differential equation that is analogous to the canonical Stefan condition. We apply this theory to the question of grounding-line stability under conditions of retrograde bed slope in a suite of calculations with different basal topography. A subset of these have basal topography inspired by the Pine Island glacier, where basal depth varies in both the along-flow and across-flow directions. Our results indicate that unstable retreat of the grounding line over retrograde beds is a robust feature of models that evolve based on force balance at the grounding line. We conclude, based on our simplified model, that unstable grounding-line recession may already be occurring at the Pine Island glacier. © 2010 The Royal Society. |
format |
Article in Journal/Newspaper |
author |
Katz, R Worster, MG |
spellingShingle |
Katz, R Worster, MG Stability of ice-sheet grounding lines |
author_facet |
Katz, R Worster, MG |
author_sort |
Katz, R |
title |
Stability of ice-sheet grounding lines |
title_short |
Stability of ice-sheet grounding lines |
title_full |
Stability of ice-sheet grounding lines |
title_fullStr |
Stability of ice-sheet grounding lines |
title_full_unstemmed |
Stability of ice-sheet grounding lines |
title_sort |
stability of ice-sheet grounding lines |
publishDate |
2016 |
url |
https://doi.org/10.1098/rspa.2009.0434 https://ora.ox.ac.uk/objects/uuid:5fd4f7f7-b68b-45e6-9f97-b30dd8c24252 |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Antarctic Pine Island Glacier West Antarctic Ice Sheet |
geographic_facet |
Antarctic Pine Island Glacier West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Ice Sheet Pine Island Glacier |
genre_facet |
Antarc* Antarctic Ice Sheet Pine Island Glacier |
op_relation |
doi:10.1098/rspa.2009.0434 https://ora.ox.ac.uk/objects/uuid:5fd4f7f7-b68b-45e6-9f97-b30dd8c24252 https://doi.org/10.1098/rspa.2009.0434 |
op_rights |
info:eu-repo/semantics/embargoedAccess |
op_doi |
https://doi.org/10.1098/rspa.2009.0434 |
container_title |
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences |
container_volume |
466 |
container_issue |
2118 |
container_start_page |
1597 |
op_container_end_page |
1620 |
_version_ |
1811636029124247552 |