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–ice shelf system. The dynamics of marine ice...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.643.7907 2023-05-15T13:54:36+02:00 Stability of ice-sheet grounding lines F. Katz M. Grae Worster The Pennsylvania State University CiteSeerX Archives 2010 application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.643.7907 http://www.earth.ox.ac.uk/~richardk/res/groundingLine/Katz_Worster_PRSA_inpress.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.643.7907 http://www.earth.ox.ac.uk/~richardk/res/groundingLine/Katz_Worster_PRSA_inpress.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.earth.ox.ac.uk/~richardk/res/groundingLine/Katz_Worster_PRSA_inpress.pdf ice sheet grounding line ice shelf Antarctica Pine Island glacier sea text 2010 ftciteseerx 2016-01-08T16:04:59Z 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–ice shelf 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. Text Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Glacier Unknown Antarctic Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) West Antarctic Ice Sheet |
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collection |
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op_collection_id |
ftciteseerx |
language |
English |
topic |
ice sheet grounding line ice shelf Antarctica Pine Island glacier sea |
spellingShingle |
ice sheet grounding line ice shelf Antarctica Pine Island glacier sea F. Katz M. Grae Worster Stability of ice-sheet grounding lines |
topic_facet |
ice sheet grounding line ice shelf Antarctica Pine Island glacier sea |
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–ice shelf 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. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
F. Katz M. Grae Worster |
author_facet |
F. Katz M. Grae Worster |
author_sort |
F. Katz |
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 |
2010 |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.643.7907 http://www.earth.ox.ac.uk/~richardk/res/groundingLine/Katz_Worster_PRSA_inpress.pdf |
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 Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Glacier |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Pine Island Pine Island Glacier |
op_source |
http://www.earth.ox.ac.uk/~richardk/res/groundingLine/Katz_Worster_PRSA_inpress.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.643.7907 http://www.earth.ox.ac.uk/~richardk/res/groundingLine/Katz_Worster_PRSA_inpress.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766260583444774912 |