Simulating the Laurentide Ice Sheet of the Last Glacial Maximum
In the last decades, great effort has been made to reconstruct the Laurentide Ice Sheet (LIS) during the Last Glacial Maximum (LGM; ca. 21 000 years before present, 21 kyr ago). Uncertainties underlying its modelling have led to notable differences in fundamental features such as its maximum elevati...
Published in: | The Cryosphere |
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Language: | English |
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2023
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ftpotsdamik:oai:publications.pik-potsdam.de:item_29053 2024-01-07T09:43:57+01:00 Simulating the Laurentide Ice Sheet of the Last Glacial Maximum Moreno-Parada, D. Alvarez-Solas, J. Blasco, J. Montoya, M. Robinson, A. 2023-05-25 application/pdf https://publications.pik-potsdam.de/pubman/item/item_29053 https://publications.pik-potsdam.de/pubman/item/item_29053_1/component/file_29069/29053oa.pdf eng eng info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-17-2139-2023 https://publications.pik-potsdam.de/pubman/item/item_29053 https://publications.pik-potsdam.de/pubman/item/item_29053_1/component/file_29069/29053oa.pdf info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by/4.0/ The Cryosphere info:eu-repo/semantics/article 2023 ftpotsdamik https://doi.org/10.5194/tc-17-2139-2023 2023-12-11T00:45:02Z In the last decades, great effort has been made to reconstruct the Laurentide Ice Sheet (LIS) during the Last Glacial Maximum (LGM; ca. 21 000 years before present, 21 kyr ago). Uncertainties underlying its modelling have led to notable differences in fundamental features such as its maximum elevation, extent and total volume. As a result, the uncertainty in ice dynamics and thus in ice extent, volume and ice stream stability remains large. We herein use a higher-order three-dimensional ice sheet model to simulate the LIS under LGM boundary conditions for a number of basal friction formulations of varying complexity. Their consequences for the Laurentide ice streams, configuration, extent and volume are explicitly quantified. Total volume and ice extent generally reach a constant equilibrium value that falls close to prior LIS reconstructions. Simulations exhibit high sensitivity to the dependency of the basal shear stress on the sliding velocity. In particular, a regularised Coulomb friction formulation appears to be the best choice in terms of ice volume and ice stream realism. Pronounced differences are found when the basal friction stress is thermomechanically coupled: the base remains colder, and the LIS volume is lower than in the purely mechanical friction scenario counterpart. Thermomechanical coupling is fundamental for producing rapid ice streaming, yet it leads to a similar ice distribution overall. Article in Journal/Newspaper Ice Sheet The Cryosphere Publication Database PIK (Potsdam Institute for Climate Impact Research) The Cryosphere 17 5 2139 2156 |
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Open Polar |
collection |
Publication Database PIK (Potsdam Institute for Climate Impact Research) |
op_collection_id |
ftpotsdamik |
language |
English |
description |
In the last decades, great effort has been made to reconstruct the Laurentide Ice Sheet (LIS) during the Last Glacial Maximum (LGM; ca. 21 000 years before present, 21 kyr ago). Uncertainties underlying its modelling have led to notable differences in fundamental features such as its maximum elevation, extent and total volume. As a result, the uncertainty in ice dynamics and thus in ice extent, volume and ice stream stability remains large. We herein use a higher-order three-dimensional ice sheet model to simulate the LIS under LGM boundary conditions for a number of basal friction formulations of varying complexity. Their consequences for the Laurentide ice streams, configuration, extent and volume are explicitly quantified. Total volume and ice extent generally reach a constant equilibrium value that falls close to prior LIS reconstructions. Simulations exhibit high sensitivity to the dependency of the basal shear stress on the sliding velocity. In particular, a regularised Coulomb friction formulation appears to be the best choice in terms of ice volume and ice stream realism. Pronounced differences are found when the basal friction stress is thermomechanically coupled: the base remains colder, and the LIS volume is lower than in the purely mechanical friction scenario counterpart. Thermomechanical coupling is fundamental for producing rapid ice streaming, yet it leads to a similar ice distribution overall. |
format |
Article in Journal/Newspaper |
author |
Moreno-Parada, D. Alvarez-Solas, J. Blasco, J. Montoya, M. Robinson, A. |
spellingShingle |
Moreno-Parada, D. Alvarez-Solas, J. Blasco, J. Montoya, M. Robinson, A. Simulating the Laurentide Ice Sheet of the Last Glacial Maximum |
author_facet |
Moreno-Parada, D. Alvarez-Solas, J. Blasco, J. Montoya, M. Robinson, A. |
author_sort |
Moreno-Parada, D. |
title |
Simulating the Laurentide Ice Sheet of the Last Glacial Maximum |
title_short |
Simulating the Laurentide Ice Sheet of the Last Glacial Maximum |
title_full |
Simulating the Laurentide Ice Sheet of the Last Glacial Maximum |
title_fullStr |
Simulating the Laurentide Ice Sheet of the Last Glacial Maximum |
title_full_unstemmed |
Simulating the Laurentide Ice Sheet of the Last Glacial Maximum |
title_sort |
simulating the laurentide ice sheet of the last glacial maximum |
publishDate |
2023 |
url |
https://publications.pik-potsdam.de/pubman/item/item_29053 https://publications.pik-potsdam.de/pubman/item/item_29053_1/component/file_29069/29053oa.pdf |
genre |
Ice Sheet The Cryosphere |
genre_facet |
Ice Sheet The Cryosphere |
op_source |
The Cryosphere |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-17-2139-2023 https://publications.pik-potsdam.de/pubman/item/item_29053 https://publications.pik-potsdam.de/pubman/item/item_29053_1/component/file_29069/29053oa.pdf |
op_rights |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.5194/tc-17-2139-2023 |
container_title |
The Cryosphere |
container_volume |
17 |
container_issue |
5 |
container_start_page |
2139 |
op_container_end_page |
2156 |
_version_ |
1787425257982787584 |