Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds
Basal conditions directly control the glacier sliding rate and the dynamic discharge of ice. Recent glacier destabilization events indicate that some marine-terminating glaciers quickly respond to lubricated beds with increased flow speed, but the underlying physics, especially how this vulnerabilit...
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Copernicus Publications
2022
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Online Access: | https://doi.org/10.5194/tc-16-1431-2022 https://tc.copernicus.org/articles/16/1431/2022/tc-16-1431-2022.pdf https://doaj.org/article/5b27d1d942ef46db94a952d0e3325948 |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:5b27d1d942ef46db94a952d0e3325948 2023-05-15T15:06:57+02:00 Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds W. Zheng 2022-04-01 https://doi.org/10.5194/tc-16-1431-2022 https://tc.copernicus.org/articles/16/1431/2022/tc-16-1431-2022.pdf https://doaj.org/article/5b27d1d942ef46db94a952d0e3325948 en eng Copernicus Publications doi:10.5194/tc-16-1431-2022 1994-0416 1994-0424 https://tc.copernicus.org/articles/16/1431/2022/tc-16-1431-2022.pdf https://doaj.org/article/5b27d1d942ef46db94a952d0e3325948 undefined The Cryosphere, Vol 16, Pp 1431-1445 (2022) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2022 fttriple https://doi.org/10.5194/tc-16-1431-2022 2023-01-22T17:50:52Z Basal conditions directly control the glacier sliding rate and the dynamic discharge of ice. Recent glacier destabilization events indicate that some marine-terminating glaciers quickly respond to lubricated beds with increased flow speed, but the underlying physics, especially how this vulnerability relates to glacier geometry and flow characteristics, remains unclear. This paper presents a 1D physical framework for glacier dynamic vulnerability assuming sudden basal lubrication as an initial perturbation. In this new model, two quantities determine the scale and the areal extent of the subsequent thinning and acceleration after the bed is lubricated: Péclet number (Pe) and the product of glacier speed and thickness gradient (dubbed J0 in this study). To validate the model, this paper calculates Pe and J0 using multi-sourced data from 1996 to 1998 for outlet glaciers in the Greenland ice sheet and Austfonna ice cap, Svalbard, and compares the results with the glacier speed change during 1996/1998–2018. Glaciers with lower Pe and J0 are more likely to accelerate during this 20-year span than those with higher Pe and J0, which matches the model prediction. A combined factor of ice thickness, surface slope, and initial flow speed physically determines how much and how fast glaciers respond to lubricated beds in terms of speed, elevation, and terminus change. Article in Journal/Newspaper Arctic Austfonna glacier glacier Greenland Ice cap Ice Sheet Svalbard The Cryosphere Unknown Arctic Austfonna ENVELOPE(24.559,24.559,79.835,79.835) Greenland Svalbard The Cryosphere 16 4 1431 1445 |
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English |
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geo envir |
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geo envir W. Zheng Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds |
topic_facet |
geo envir |
description |
Basal conditions directly control the glacier sliding rate and the dynamic discharge of ice. Recent glacier destabilization events indicate that some marine-terminating glaciers quickly respond to lubricated beds with increased flow speed, but the underlying physics, especially how this vulnerability relates to glacier geometry and flow characteristics, remains unclear. This paper presents a 1D physical framework for glacier dynamic vulnerability assuming sudden basal lubrication as an initial perturbation. In this new model, two quantities determine the scale and the areal extent of the subsequent thinning and acceleration after the bed is lubricated: Péclet number (Pe) and the product of glacier speed and thickness gradient (dubbed J0 in this study). To validate the model, this paper calculates Pe and J0 using multi-sourced data from 1996 to 1998 for outlet glaciers in the Greenland ice sheet and Austfonna ice cap, Svalbard, and compares the results with the glacier speed change during 1996/1998–2018. Glaciers with lower Pe and J0 are more likely to accelerate during this 20-year span than those with higher Pe and J0, which matches the model prediction. A combined factor of ice thickness, surface slope, and initial flow speed physically determines how much and how fast glaciers respond to lubricated beds in terms of speed, elevation, and terminus change. |
format |
Article in Journal/Newspaper |
author |
W. Zheng |
author_facet |
W. Zheng |
author_sort |
W. Zheng |
title |
Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds |
title_short |
Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds |
title_full |
Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds |
title_fullStr |
Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds |
title_full_unstemmed |
Glacier geometry and flow speed determine how Arctic marine-terminating glaciers respond to lubricated beds |
title_sort |
glacier geometry and flow speed determine how arctic marine-terminating glaciers respond to lubricated beds |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://doi.org/10.5194/tc-16-1431-2022 https://tc.copernicus.org/articles/16/1431/2022/tc-16-1431-2022.pdf https://doaj.org/article/5b27d1d942ef46db94a952d0e3325948 |
long_lat |
ENVELOPE(24.559,24.559,79.835,79.835) |
geographic |
Arctic Austfonna Greenland Svalbard |
geographic_facet |
Arctic Austfonna Greenland Svalbard |
genre |
Arctic Austfonna glacier glacier Greenland Ice cap Ice Sheet Svalbard The Cryosphere |
genre_facet |
Arctic Austfonna glacier glacier Greenland Ice cap Ice Sheet Svalbard The Cryosphere |
op_source |
The Cryosphere, Vol 16, Pp 1431-1445 (2022) |
op_relation |
doi:10.5194/tc-16-1431-2022 1994-0416 1994-0424 https://tc.copernicus.org/articles/16/1431/2022/tc-16-1431-2022.pdf https://doaj.org/article/5b27d1d942ef46db94a952d0e3325948 |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-16-1431-2022 |
container_title |
The Cryosphere |
container_volume |
16 |
container_issue |
4 |
container_start_page |
1431 |
op_container_end_page |
1445 |
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1766338528393822208 |