The role of subtemperate slip in thermally driven ice stream margin migration
The amount of ice discharged by an ice stream depends on its width, and the widths of unconfined ice streams such as the Siple Coast ice streams in West Antarctica have been observed to evolve on decadal to centennial timescales. Thermally driven widening of ice streams provides a mechanism for this...
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ftdoajarticles:oai:doaj.org/article:22cacc8632b94545a2d588acd8ee2894 2023-05-15T13:41:54+02:00 The role of subtemperate slip in thermally driven ice stream margin migration M. Haseloff C. Schoof O. Gagliardini 2018-08-01T00:00:00Z https://doi.org/10.5194/tc-12-2545-2018 https://doaj.org/article/22cacc8632b94545a2d588acd8ee2894 EN eng Copernicus Publications https://www.the-cryosphere.net/12/2545/2018/tc-12-2545-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-2545-2018 1994-0416 1994-0424 https://doaj.org/article/22cacc8632b94545a2d588acd8ee2894 The Cryosphere, Vol 12, Pp 2545-2568 (2018) Environmental sciences GE1-350 Geology QE1-996.5 article 2018 ftdoajarticles https://doi.org/10.5194/tc-12-2545-2018 2022-12-31T11:34:09Z The amount of ice discharged by an ice stream depends on its width, and the widths of unconfined ice streams such as the Siple Coast ice streams in West Antarctica have been observed to evolve on decadal to centennial timescales. Thermally driven widening of ice streams provides a mechanism for this observed variability through melting of the frozen beds of adjacent ice ridges. This widening is driven by the heat dissipation in the ice stream margin, where strain rates are high, and at the bed of the ice ridge, where subtemperate sliding is possible. The inflow of cold ice from the neighboring ice ridges impedes ice stream widening. Determining the migration rate of the margin requires resolving conductive and advective heat transfer processes on very small scales in the ice stream margin, and these processes cannot be resolved by large-scale ice sheet models. Here, we exploit the thermal boundary layer structure in the ice stream margin to investigate how the migration rate depends on these different processes. We derive a parameterization of the migration rate in terms of parameters that can be estimated from observations or large-scale model outputs, including the lateral shear stress in the ice stream margin, the ice thickness of the stream, the influx of ice from the ridge, and the bed temperature of the ice ridge. This parameterization will allow the incorporation of ice stream margin migration into large-scale ice sheet models. Article in Journal/Newspaper Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica Directory of Open Access Journals: DOAJ Articles West Antarctica Siple ENVELOPE(-83.917,-83.917,-75.917,-75.917) Siple Coast ENVELOPE(-155.000,-155.000,-82.000,-82.000) The Cryosphere 12 8 2545 2568 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 M. Haseloff C. Schoof O. Gagliardini The role of subtemperate slip in thermally driven ice stream margin migration |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
The amount of ice discharged by an ice stream depends on its width, and the widths of unconfined ice streams such as the Siple Coast ice streams in West Antarctica have been observed to evolve on decadal to centennial timescales. Thermally driven widening of ice streams provides a mechanism for this observed variability through melting of the frozen beds of adjacent ice ridges. This widening is driven by the heat dissipation in the ice stream margin, where strain rates are high, and at the bed of the ice ridge, where subtemperate sliding is possible. The inflow of cold ice from the neighboring ice ridges impedes ice stream widening. Determining the migration rate of the margin requires resolving conductive and advective heat transfer processes on very small scales in the ice stream margin, and these processes cannot be resolved by large-scale ice sheet models. Here, we exploit the thermal boundary layer structure in the ice stream margin to investigate how the migration rate depends on these different processes. We derive a parameterization of the migration rate in terms of parameters that can be estimated from observations or large-scale model outputs, including the lateral shear stress in the ice stream margin, the ice thickness of the stream, the influx of ice from the ridge, and the bed temperature of the ice ridge. This parameterization will allow the incorporation of ice stream margin migration into large-scale ice sheet models. |
format |
Article in Journal/Newspaper |
author |
M. Haseloff C. Schoof O. Gagliardini |
author_facet |
M. Haseloff C. Schoof O. Gagliardini |
author_sort |
M. Haseloff |
title |
The role of subtemperate slip in thermally driven ice stream margin migration |
title_short |
The role of subtemperate slip in thermally driven ice stream margin migration |
title_full |
The role of subtemperate slip in thermally driven ice stream margin migration |
title_fullStr |
The role of subtemperate slip in thermally driven ice stream margin migration |
title_full_unstemmed |
The role of subtemperate slip in thermally driven ice stream margin migration |
title_sort |
role of subtemperate slip in thermally driven ice stream margin migration |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-2545-2018 https://doaj.org/article/22cacc8632b94545a2d588acd8ee2894 |
long_lat |
ENVELOPE(-83.917,-83.917,-75.917,-75.917) ENVELOPE(-155.000,-155.000,-82.000,-82.000) |
geographic |
West Antarctica Siple Siple Coast |
geographic_facet |
West Antarctica Siple Siple Coast |
genre |
Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica |
genre_facet |
Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica |
op_source |
The Cryosphere, Vol 12, Pp 2545-2568 (2018) |
op_relation |
https://www.the-cryosphere.net/12/2545/2018/tc-12-2545-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-2545-2018 1994-0416 1994-0424 https://doaj.org/article/22cacc8632b94545a2d588acd8ee2894 |
op_doi |
https://doi.org/10.5194/tc-12-2545-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
8 |
container_start_page |
2545 |
op_container_end_page |
2568 |
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1766159872825491456 |