Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip
Abstract Sea-level projections depend sensitively on the parameterization used for basal slip in glacier flow models. During slip over rock-beds, ice-bed separation increases with slip velocity and basal water pressure. We present a method for using these variables and measured bed topography to est...
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Cambridge University Press (CUP)
2022
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Online Access: | http://dx.doi.org/10.1017/jog.2022.63 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143022000636 |
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crcambridgeupr:10.1017/jog.2022.63 2024-03-03T08:46:00+00:00 Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip Woodard, Jacob B. Zoet, Lucas K. Iverson, Neal R. Helanow, Christian United States National Science Foundation 2022 http://dx.doi.org/10.1017/jog.2022.63 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143022000636 en eng Cambridge University Press (CUP) https://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 69, issue 274, page 324-332 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 2022 crcambridgeupr https://doi.org/10.1017/jog.2022.63 2024-02-08T08:31:23Z Abstract Sea-level projections depend sensitively on the parameterization used for basal slip in glacier flow models. During slip over rock-beds, ice-bed separation increases with slip velocity and basal water pressure. We present a method for using these variables and measured bed topography to estimate the average bed slope in contact with ice, ${\bar m}$ . Three-dimensional numerical modeling of slip over small areas of former beds has shown that changes in ${\bar m}$ with increasing slip velocity and water pressure mimic changes in basal drag. Computed values of ${\bar m}$ can thus provide the form of the slip law that relates drag to velocity and water pressure, avoiding computationally expensive numerical modeling. The method is applied to 618 sections from four former glacier beds. Results generally show an increase in ${\bar m}$ , and hence inferred basal drag, with slip velocity up to a limiting value, consistent with a regularized Coulomb slip law. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 1 9 |
institution |
Open Polar |
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Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Woodard, Jacob B. Zoet, Lucas K. Iverson, Neal R. Helanow, Christian Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
topic_facet |
Earth-Surface Processes |
description |
Abstract Sea-level projections depend sensitively on the parameterization used for basal slip in glacier flow models. During slip over rock-beds, ice-bed separation increases with slip velocity and basal water pressure. We present a method for using these variables and measured bed topography to estimate the average bed slope in contact with ice, ${\bar m}$ . Three-dimensional numerical modeling of slip over small areas of former beds has shown that changes in ${\bar m}$ with increasing slip velocity and water pressure mimic changes in basal drag. Computed values of ${\bar m}$ can thus provide the form of the slip law that relates drag to velocity and water pressure, avoiding computationally expensive numerical modeling. The method is applied to 618 sections from four former glacier beds. Results generally show an increase in ${\bar m}$ , and hence inferred basal drag, with slip velocity up to a limiting value, consistent with a regularized Coulomb slip law. |
author2 |
United States National Science Foundation |
format |
Article in Journal/Newspaper |
author |
Woodard, Jacob B. Zoet, Lucas K. Iverson, Neal R. Helanow, Christian |
author_facet |
Woodard, Jacob B. Zoet, Lucas K. Iverson, Neal R. Helanow, Christian |
author_sort |
Woodard, Jacob B. |
title |
Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
title_short |
Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
title_full |
Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
title_fullStr |
Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
title_full_unstemmed |
Inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
title_sort |
inferring forms of glacier slip laws from estimates of ice-bed separation during glacier slip |
publisher |
Cambridge University Press (CUP) |
publishDate |
2022 |
url |
http://dx.doi.org/10.1017/jog.2022.63 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143022000636 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 69, issue 274, page 324-332 ISSN 0022-1430 1727-5652 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2022.63 |
container_title |
Journal of Glaciology |
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1 |
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9 |
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1792501782736273408 |