Dynamic response of Antarctic ice shelves to bedrock uncertainty
Accurate and extensive bedrock geometry data is essential in ice sheet modelling. The shape of the bedrock on fine scales can influence ice sheet evolution, for example through the formation of pinning points that alter grounding line dynamics. Here we test the sensitivity of the BISICLES adaptive m...
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ftcopernicus:oai:publications.copernicus.org:tc23672 2023-05-15T13:22:03+02:00 Dynamic response of Antarctic ice shelves to bedrock uncertainty Sun, S. Cornford, S. L. Liu, Y. Moore, J. C. 2018-09-27 application/pdf https://doi.org/10.5194/tc-8-1561-2014 https://tc.copernicus.org/articles/8/1561/2014/ eng eng doi:10.5194/tc-8-1561-2014 https://tc.copernicus.org/articles/8/1561/2014/ eISSN: 1994-0424 Text 2018 ftcopernicus https://doi.org/10.5194/tc-8-1561-2014 2020-07-20T16:25:00Z Accurate and extensive bedrock geometry data is essential in ice sheet modelling. The shape of the bedrock on fine scales can influence ice sheet evolution, for example through the formation of pinning points that alter grounding line dynamics. Here we test the sensitivity of the BISICLES adaptive mesh ice sheet model to small-amplitude height fluctuations on different spatial scales in the bedrock topography provided by Bedmap2 in the catchments of Pine Island Glacier, the Amery Ice shelf and a region of East Antarctica including the Aurora Basin, Law Dome and Totten Glacier. We generate an ensemble of bedrock topographies by adding random noise to the Bedmap2 data with amplitude determined by the accompanying estimates of bedrock uncertainty. We find that the small-amplitude fluctuations result in only minor changes in the way these glaciers evolve. However, lower-frequency noise, with a broad spatial scale (over tens of kilometres) is more important than higher-frequency noise even when the features have the same height amplitudes and the total noise power is maintained. This is cause for optimism regarding credible sea level rise estimates with presently achievable density of thickness measurements. Pine Island Glacier and the region around Totten Glacier and Law Dome undergo substantial retreat and appear to be more sensitive to errors in bed topography than the Amery Ice shelf region which remains stable under the present-day observational data uncertainty. Text Amery Ice Shelf Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelf Ice Shelves Pine Island Pine Island Glacier Totten Glacier Copernicus Publications: E-Journals Amery ENVELOPE(-94.063,-94.063,56.565,56.565) Amery Ice Shelf ENVELOPE(71.000,71.000,-69.750,-69.750) Antarctic East Antarctica Law Dome ENVELOPE(112.833,112.833,-66.733,-66.733) Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Totten Glacier ENVELOPE(116.333,116.333,-66.833,-66.833) The Cryosphere 8 4 1561 1576 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
Accurate and extensive bedrock geometry data is essential in ice sheet modelling. The shape of the bedrock on fine scales can influence ice sheet evolution, for example through the formation of pinning points that alter grounding line dynamics. Here we test the sensitivity of the BISICLES adaptive mesh ice sheet model to small-amplitude height fluctuations on different spatial scales in the bedrock topography provided by Bedmap2 in the catchments of Pine Island Glacier, the Amery Ice shelf and a region of East Antarctica including the Aurora Basin, Law Dome and Totten Glacier. We generate an ensemble of bedrock topographies by adding random noise to the Bedmap2 data with amplitude determined by the accompanying estimates of bedrock uncertainty. We find that the small-amplitude fluctuations result in only minor changes in the way these glaciers evolve. However, lower-frequency noise, with a broad spatial scale (over tens of kilometres) is more important than higher-frequency noise even when the features have the same height amplitudes and the total noise power is maintained. This is cause for optimism regarding credible sea level rise estimates with presently achievable density of thickness measurements. Pine Island Glacier and the region around Totten Glacier and Law Dome undergo substantial retreat and appear to be more sensitive to errors in bed topography than the Amery Ice shelf region which remains stable under the present-day observational data uncertainty. |
format |
Text |
author |
Sun, S. Cornford, S. L. Liu, Y. Moore, J. C. |
spellingShingle |
Sun, S. Cornford, S. L. Liu, Y. Moore, J. C. Dynamic response of Antarctic ice shelves to bedrock uncertainty |
author_facet |
Sun, S. Cornford, S. L. Liu, Y. Moore, J. C. |
author_sort |
Sun, S. |
title |
Dynamic response of Antarctic ice shelves to bedrock uncertainty |
title_short |
Dynamic response of Antarctic ice shelves to bedrock uncertainty |
title_full |
Dynamic response of Antarctic ice shelves to bedrock uncertainty |
title_fullStr |
Dynamic response of Antarctic ice shelves to bedrock uncertainty |
title_full_unstemmed |
Dynamic response of Antarctic ice shelves to bedrock uncertainty |
title_sort |
dynamic response of antarctic ice shelves to bedrock uncertainty |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-8-1561-2014 https://tc.copernicus.org/articles/8/1561/2014/ |
long_lat |
ENVELOPE(-94.063,-94.063,56.565,56.565) ENVELOPE(71.000,71.000,-69.750,-69.750) ENVELOPE(112.833,112.833,-66.733,-66.733) ENVELOPE(-101.000,-101.000,-75.000,-75.000) ENVELOPE(116.333,116.333,-66.833,-66.833) |
geographic |
Amery Amery Ice Shelf Antarctic East Antarctica Law Dome Pine Island Glacier Totten Glacier |
geographic_facet |
Amery Amery Ice Shelf Antarctic East Antarctica Law Dome Pine Island Glacier Totten Glacier |
genre |
Amery Ice Shelf Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelf Ice Shelves Pine Island Pine Island Glacier Totten Glacier |
genre_facet |
Amery Ice Shelf Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelf Ice Shelves Pine Island Pine Island Glacier Totten Glacier |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-8-1561-2014 https://tc.copernicus.org/articles/8/1561/2014/ |
op_doi |
https://doi.org/10.5194/tc-8-1561-2014 |
container_title |
The Cryosphere |
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8 |
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4 |
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1561 |
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1576 |
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1766363030371696640 |