In search of ice-stream sticky spots
Abstract The basal shear stress of an ice stream may be supported disproportionately on localized regions or “sticky spots”. The drag induced by large bedrock bumps sticking into the base of an ice stream is the most likely cause of sticky spots. Discontinuity of lubricating till can cause sticky sp...
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Language: | English |
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Cambridge University Press (CUP)
1993
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Online Access: | http://dx.doi.org/10.1017/s0022143000016336 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000016336 |
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crcambridgeupr:10.1017/s0022143000016336 2024-09-15T17:48:40+00:00 In search of ice-stream sticky spots Alley, Richard B. 1993 http://dx.doi.org/10.1017/s0022143000016336 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000016336 en eng Cambridge University Press (CUP) Journal of Glaciology volume 39, issue 133, page 447-454 ISSN 0022-1430 1727-5652 journal-article 1993 crcambridgeupr https://doi.org/10.1017/s0022143000016336 2024-07-31T04:03:43Z Abstract The basal shear stress of an ice stream may be supported disproportionately on localized regions or “sticky spots”. The drag induced by large bedrock bumps sticking into the base of an ice stream is the most likely cause of sticky spots. Discontinuity of lubricating till can cause sticky spots, but they will collect lubricating water and therefore are unlikely to support a shear stress of more than a few tenths of a bar unless they contain abundant large bumps. Raised regions on the ice-air surface can also cause moderate increases in the shear stress supported on the bed beneath. Surveys of large-scale bed roughness would identify sticky spots caused by bedrock bumps, water-pressure measurements in regions of thin or zero till might reveal whether they were sticky spots, and strain grids across the margins of ice-surface highs would show whether the highs were causing sticky spots. Sticky spots probably are not dominant in controlling Ice Stream Β near the Upstream Β camp, West Antarctica. Article in Journal/Newspaper Antarc* Antarctica Journal of Glaciology West Antarctica Cambridge University Press Journal of Glaciology 39 133 447 454 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract The basal shear stress of an ice stream may be supported disproportionately on localized regions or “sticky spots”. The drag induced by large bedrock bumps sticking into the base of an ice stream is the most likely cause of sticky spots. Discontinuity of lubricating till can cause sticky spots, but they will collect lubricating water and therefore are unlikely to support a shear stress of more than a few tenths of a bar unless they contain abundant large bumps. Raised regions on the ice-air surface can also cause moderate increases in the shear stress supported on the bed beneath. Surveys of large-scale bed roughness would identify sticky spots caused by bedrock bumps, water-pressure measurements in regions of thin or zero till might reveal whether they were sticky spots, and strain grids across the margins of ice-surface highs would show whether the highs were causing sticky spots. Sticky spots probably are not dominant in controlling Ice Stream Β near the Upstream Β camp, West Antarctica. |
format |
Article in Journal/Newspaper |
author |
Alley, Richard B. |
spellingShingle |
Alley, Richard B. In search of ice-stream sticky spots |
author_facet |
Alley, Richard B. |
author_sort |
Alley, Richard B. |
title |
In search of ice-stream sticky spots |
title_short |
In search of ice-stream sticky spots |
title_full |
In search of ice-stream sticky spots |
title_fullStr |
In search of ice-stream sticky spots |
title_full_unstemmed |
In search of ice-stream sticky spots |
title_sort |
in search of ice-stream sticky spots |
publisher |
Cambridge University Press (CUP) |
publishDate |
1993 |
url |
http://dx.doi.org/10.1017/s0022143000016336 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000016336 |
genre |
Antarc* Antarctica Journal of Glaciology West Antarctica |
genre_facet |
Antarc* Antarctica Journal of Glaciology West Antarctica |
op_source |
Journal of Glaciology volume 39, issue 133, page 447-454 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000016336 |
container_title |
Journal of Glaciology |
container_volume |
39 |
container_issue |
133 |
container_start_page |
447 |
op_container_end_page |
454 |
_version_ |
1810290148438441984 |