The role of subtemperate slip in thermally driven ice stream margin migration
International audience 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 provid...
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ftinsu:oai:HAL:insu-03706500v1 2024-04-28T07:58:46+00:00 The role of subtemperate slip in thermally driven ice stream margin migration Haseloff, Marianne Schoof, Christian Gagliardini, Olivier Institut des Géosciences de l’Environnement (IGE) Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ) 2018 https://insu.hal.science/insu-03706500 https://insu.hal.science/insu-03706500/document https://insu.hal.science/insu-03706500/file/tc-12-2545-2018.pdf https://doi.org/10.5194/tc-12-2545-2018 en eng HAL CCSD Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-12-2545-2018 insu-03706500 https://insu.hal.science/insu-03706500 https://insu.hal.science/insu-03706500/document https://insu.hal.science/insu-03706500/file/tc-12-2545-2018.pdf BIBCODE: 2018TCry.12.2545H doi:10.5194/tc-12-2545-2018 http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://insu.hal.science/insu-03706500 The Cryosphere, 2018, 12, pp.2545-2568. ⟨10.5194/tc-12-2545-2018⟩ [SDU]Sciences of the Universe [physics] info:eu-repo/semantics/article Journal articles 2018 ftinsu https://doi.org/10.5194/tc-12-2545-2018 2024-04-05T00:32:43Z International audience 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 Institut national des sciences de l'Univers: HAL-INSU The Cryosphere 12 8 2545 2568 |
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Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[SDU]Sciences of the Universe [physics] |
spellingShingle |
[SDU]Sciences of the Universe [physics] Haseloff, Marianne Schoof, Christian Gagliardini, Olivier The role of subtemperate slip in thermally driven ice stream margin migration |
topic_facet |
[SDU]Sciences of the Universe [physics] |
description |
International audience 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. |
author2 |
Institut des Géosciences de l’Environnement (IGE) Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ) |
format |
Article in Journal/Newspaper |
author |
Haseloff, Marianne Schoof, Christian Gagliardini, Olivier |
author_facet |
Haseloff, Marianne Schoof, Christian Gagliardini, Olivier |
author_sort |
Haseloff, Marianne |
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 |
HAL CCSD |
publishDate |
2018 |
url |
https://insu.hal.science/insu-03706500 https://insu.hal.science/insu-03706500/document https://insu.hal.science/insu-03706500/file/tc-12-2545-2018.pdf https://doi.org/10.5194/tc-12-2545-2018 |
genre |
Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica |
genre_facet |
Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica |
op_source |
ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://insu.hal.science/insu-03706500 The Cryosphere, 2018, 12, pp.2545-2568. ⟨10.5194/tc-12-2545-2018⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-12-2545-2018 insu-03706500 https://insu.hal.science/insu-03706500 https://insu.hal.science/insu-03706500/document https://insu.hal.science/insu-03706500/file/tc-12-2545-2018.pdf BIBCODE: 2018TCry.12.2545H doi:10.5194/tc-12-2545-2018 |
op_rights |
http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess |
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 |
_version_ |
1797571646626725888 |