Persistence and variability of ice-stream grounding lines on retrograde bed slopes
In many ice streams, basal resistance varies in space and time due to the dynamically evolving properties of subglacial till. These variations can cause internally generated oscillations in ice-stream flow. However, the potential for such variations in basal properties is not considered by conventio...
Published in: | The Cryosphere |
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Language: | English |
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Copernicus Publications
2016
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fttriple:oai:gotriple.eu:oai:doaj.org/article:8e84665dc16646e4a9cf7104318c0fbd 2023-05-15T14:05:10+02:00 Persistence and variability of ice-stream grounding lines on retrograde bed slopes A. A. Robel C. Schoof E. Tziperman 2016-08-01 https://doi.org/10.5194/tc-10-1883-2016 http://www.the-cryosphere.net/10/1883/2016/tc-10-1883-2016.pdf https://doaj.org/article/8e84665dc16646e4a9cf7104318c0fbd en eng Copernicus Publications 1994-0416 1994-0424 doi:10.5194/tc-10-1883-2016 http://www.the-cryosphere.net/10/1883/2016/tc-10-1883-2016.pdf https://doaj.org/article/8e84665dc16646e4a9cf7104318c0fbd undefined The Cryosphere, Vol 10, Iss 4, Pp 1883-1896 (2016) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2016 fttriple https://doi.org/10.5194/tc-10-1883-2016 2023-01-22T19:05:19Z In many ice streams, basal resistance varies in space and time due to the dynamically evolving properties of subglacial till. These variations can cause internally generated oscillations in ice-stream flow. However, the potential for such variations in basal properties is not considered by conventional theories of grounding-line stability on retrograde bed slopes, which assume that bed properties are static in time. Using a flow-line model, we show how internally generated, transient variations in ice-stream state interact with retrograde bed slopes. In contrast to predictions from the theory of the marine ice-sheet instability, our simulated grounding line is able to persist and reverse direction of migration on a retrograde bed when undergoing oscillations in the grounding-line position. In turn, the presence of a retrograde bed may also suppress or reduce the amplitude of internal oscillations in ice-stream state. We explore the physical mechanisms responsible for these behaviors and discuss the implications for observed grounding-line migration in West Antarctica. Article in Journal/Newspaper Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica Unknown West Antarctica The Cryosphere 10 4 1883 1896 |
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Open Polar |
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fttriple |
language |
English |
topic |
geo envir |
spellingShingle |
geo envir A. A. Robel C. Schoof E. Tziperman Persistence and variability of ice-stream grounding lines on retrograde bed slopes |
topic_facet |
geo envir |
description |
In many ice streams, basal resistance varies in space and time due to the dynamically evolving properties of subglacial till. These variations can cause internally generated oscillations in ice-stream flow. However, the potential for such variations in basal properties is not considered by conventional theories of grounding-line stability on retrograde bed slopes, which assume that bed properties are static in time. Using a flow-line model, we show how internally generated, transient variations in ice-stream state interact with retrograde bed slopes. In contrast to predictions from the theory of the marine ice-sheet instability, our simulated grounding line is able to persist and reverse direction of migration on a retrograde bed when undergoing oscillations in the grounding-line position. In turn, the presence of a retrograde bed may also suppress or reduce the amplitude of internal oscillations in ice-stream state. We explore the physical mechanisms responsible for these behaviors and discuss the implications for observed grounding-line migration in West Antarctica. |
format |
Article in Journal/Newspaper |
author |
A. A. Robel C. Schoof E. Tziperman |
author_facet |
A. A. Robel C. Schoof E. Tziperman |
author_sort |
A. A. Robel |
title |
Persistence and variability of ice-stream grounding lines on retrograde bed slopes |
title_short |
Persistence and variability of ice-stream grounding lines on retrograde bed slopes |
title_full |
Persistence and variability of ice-stream grounding lines on retrograde bed slopes |
title_fullStr |
Persistence and variability of ice-stream grounding lines on retrograde bed slopes |
title_full_unstemmed |
Persistence and variability of ice-stream grounding lines on retrograde bed slopes |
title_sort |
persistence and variability of ice-stream grounding lines on retrograde bed slopes |
publisher |
Copernicus Publications |
publishDate |
2016 |
url |
https://doi.org/10.5194/tc-10-1883-2016 http://www.the-cryosphere.net/10/1883/2016/tc-10-1883-2016.pdf https://doaj.org/article/8e84665dc16646e4a9cf7104318c0fbd |
geographic |
West Antarctica |
geographic_facet |
West Antarctica |
genre |
Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica |
genre_facet |
Antarc* Antarctica Ice Sheet The Cryosphere West Antarctica |
op_source |
The Cryosphere, Vol 10, Iss 4, Pp 1883-1896 (2016) |
op_relation |
1994-0416 1994-0424 doi:10.5194/tc-10-1883-2016 http://www.the-cryosphere.net/10/1883/2016/tc-10-1883-2016.pdf https://doaj.org/article/8e84665dc16646e4a9cf7104318c0fbd |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-10-1883-2016 |
container_title |
The Cryosphere |
container_volume |
10 |
container_issue |
4 |
container_start_page |
1883 |
op_container_end_page |
1896 |
_version_ |
1766276886145531904 |