Hysteretic evolution of ice rises and ice rumples in response to variations in sea level
Ice rises and ice rumples are locally grounded features found in coastal Antarctica and are surrounded by otherwise freely floating ice shelves. An ice rise has an independent flow regime, whereas the flow regime of an ice rumple conforms to that of the ice shelf and merely slows the flow of ice. In...
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ftdoajarticles:oai:doaj.org/article:9d749e37fd1348fe94a2dd612e1a2d4e 2023-05-15T13:57:52+02:00 Hysteretic evolution of ice rises and ice rumples in response to variations in sea level A. C. J. Henry R. Drews C. Schannwell V. Višnjević 2022-09-01T00:00:00Z https://doi.org/10.5194/tc-16-3889-2022 https://doaj.org/article/9d749e37fd1348fe94a2dd612e1a2d4e EN eng Copernicus Publications https://tc.copernicus.org/articles/16/3889/2022/tc-16-3889-2022.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-16-3889-2022 1994-0416 1994-0424 https://doaj.org/article/9d749e37fd1348fe94a2dd612e1a2d4e The Cryosphere, Vol 16, Pp 3889-3905 (2022) Environmental sciences GE1-350 Geology QE1-996.5 article 2022 ftdoajarticles https://doi.org/10.5194/tc-16-3889-2022 2022-12-30T21:04:24Z Ice rises and ice rumples are locally grounded features found in coastal Antarctica and are surrounded by otherwise freely floating ice shelves. An ice rise has an independent flow regime, whereas the flow regime of an ice rumple conforms to that of the ice shelf and merely slows the flow of ice. In both cases, local highs in the bathymetry are in contact with the ice shelf from below, thereby regulating the large-scale ice flow, with implications for the upstream continental grounding line position. This buttressing effect, paired with the suitability of ice rises as a climate archive, necessitates a better understanding of the transition between ice rise and ice rumple, their evolution in response to a change in sea level, and their dynamic interaction with the surrounding ice shelf. We investigate this behaviour using a three-dimensional full Stokes ice flow model with idealised ice rises and ice rumples. The simulations span end-member basal friction scenarios of almost stagnant and fully sliding ice at the ice–bed interface. We analyse the coupling with the surrounding ice shelf by comparing the deviations between the non-local full Stokes surface velocities and the local shallow ice approximation (SIA). Deviations are generally high at the ice divides and small on the lee sides. On the stoss side, where ice rise and ice shelf have opposing flow directions, deviations can be significant. Differences are negligible in the absence of basal sliding where the corresponding steady-state ice rise is larger and develops a fully independent flow regime that is well described by SIA. When sea level is increased, and a transition from ice rise to ice rumple is approached, the divide migration is more abrupt the higher the basal friction. In each scenario, the transition occurs after the stoss-side grounding line has moved over the bed high and is positioned on a retrograde slope. We identify a hysteretic response of ice rises and ice rumples to changes in sea level, with grounded area being larger in a ... Article in Journal/Newspaper Antarc* Antarctica Ice Shelf Ice Shelves The Cryosphere Directory of Open Access Journals: DOAJ Articles The Cryosphere 16 9 3889 3905 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
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English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
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Environmental sciences GE1-350 Geology QE1-996.5 A. C. J. Henry R. Drews C. Schannwell V. Višnjević Hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Ice rises and ice rumples are locally grounded features found in coastal Antarctica and are surrounded by otherwise freely floating ice shelves. An ice rise has an independent flow regime, whereas the flow regime of an ice rumple conforms to that of the ice shelf and merely slows the flow of ice. In both cases, local highs in the bathymetry are in contact with the ice shelf from below, thereby regulating the large-scale ice flow, with implications for the upstream continental grounding line position. This buttressing effect, paired with the suitability of ice rises as a climate archive, necessitates a better understanding of the transition between ice rise and ice rumple, their evolution in response to a change in sea level, and their dynamic interaction with the surrounding ice shelf. We investigate this behaviour using a three-dimensional full Stokes ice flow model with idealised ice rises and ice rumples. The simulations span end-member basal friction scenarios of almost stagnant and fully sliding ice at the ice–bed interface. We analyse the coupling with the surrounding ice shelf by comparing the deviations between the non-local full Stokes surface velocities and the local shallow ice approximation (SIA). Deviations are generally high at the ice divides and small on the lee sides. On the stoss side, where ice rise and ice shelf have opposing flow directions, deviations can be significant. Differences are negligible in the absence of basal sliding where the corresponding steady-state ice rise is larger and develops a fully independent flow regime that is well described by SIA. When sea level is increased, and a transition from ice rise to ice rumple is approached, the divide migration is more abrupt the higher the basal friction. In each scenario, the transition occurs after the stoss-side grounding line has moved over the bed high and is positioned on a retrograde slope. We identify a hysteretic response of ice rises and ice rumples to changes in sea level, with grounded area being larger in a ... |
format |
Article in Journal/Newspaper |
author |
A. C. J. Henry R. Drews C. Schannwell V. Višnjević |
author_facet |
A. C. J. Henry R. Drews C. Schannwell V. Višnjević |
author_sort |
A. C. J. Henry |
title |
Hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
title_short |
Hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
title_full |
Hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
title_fullStr |
Hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
title_full_unstemmed |
Hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
title_sort |
hysteretic evolution of ice rises and ice rumples in response to variations in sea level |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://doi.org/10.5194/tc-16-3889-2022 https://doaj.org/article/9d749e37fd1348fe94a2dd612e1a2d4e |
genre |
Antarc* Antarctica Ice Shelf Ice Shelves The Cryosphere |
genre_facet |
Antarc* Antarctica Ice Shelf Ice Shelves The Cryosphere |
op_source |
The Cryosphere, Vol 16, Pp 3889-3905 (2022) |
op_relation |
https://tc.copernicus.org/articles/16/3889/2022/tc-16-3889-2022.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-16-3889-2022 1994-0416 1994-0424 https://doaj.org/article/9d749e37fd1348fe94a2dd612e1a2d4e |
op_doi |
https://doi.org/10.5194/tc-16-3889-2022 |
container_title |
The Cryosphere |
container_volume |
16 |
container_issue |
9 |
container_start_page |
3889 |
op_container_end_page |
3905 |
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1766265790155194368 |