Geometric controls of tidewater glacier dynamics
Retreat of marine outlet glaciers often initiates depletion of inland ice through dynamic adjustments of the upstream glacier. The local topography of a fjord may promote or inhibit such retreat, and therefore fjord geometry constitutes a critical control on ice sheet mass balance. To quantify the p...
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Online Access: | https://hdl.handle.net/11250/2984317 https://doi.org/10.5194/tc-16-581-2022 |
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ftunivbergen:oai:bora.uib.no:11250/2984317 2023-05-15T16:40:37+02:00 Geometric controls of tidewater glacier dynamics Frank, Thomas Åkesson, Henning Fleurian, Basile de Morlighem, M. Nisancioglu, Kerim Hestnes 2022 application/pdf https://hdl.handle.net/11250/2984317 https://doi.org/10.5194/tc-16-581-2022 eng eng Copernicus Publications Notur/NorStore: nn4659k Norges forskningsråd: 302458 Norges forskningsråd: 287206 Notur/NorStore: ns4659k Notur/NorStore: nn9635k Notur/NorStore: ns9635k urn:issn:1994-0416 https://hdl.handle.net/11250/2984317 https://doi.org/10.5194/tc-16-581-2022 cristin:2003311 The Cryosphere. 2022, 16 (2), 581-601. Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright Author(s) 2022 The Cryosphere 581-601 16 2 Journal article Peer reviewed 2022 ftunivbergen https://doi.org/10.5194/tc-16-581-2022 2023-03-14T17:41:08Z Retreat of marine outlet glaciers often initiates depletion of inland ice through dynamic adjustments of the upstream glacier. The local topography of a fjord may promote or inhibit such retreat, and therefore fjord geometry constitutes a critical control on ice sheet mass balance. To quantify the processes of ice–topography interactions and enhance the understanding of the dynamics involved, we analyze a multitude of topographic fjord settings and scenarios using the Ice-sheet and Sea-level System Model (ISSM). We systematically study glacier retreat through a variety of artificial fjord geometries and quantify the modeled dynamics directly in relation to topographic features. We find that retreat in an upstream-widening or upstream-deepening fjord does not necessarily promote retreat, as suggested by previous studies. Conversely, it may stabilize a glacier because converging ice flow towards a constriction enhances lateral and basal shear stress gradients. An upstream-narrowing or upstream-shoaling fjord, in turn, may promote retreat since fjord walls or bed provide little stability to the glacier where ice flow diverges. Furthermore, we identify distinct quantitative relationships directly linking grounding line discharge and retreat rate to fjord topography and transfer these results to a long-term study of the retreat of Jakobshavn Isbræ. These findings offer new perspectives on ice–topography interactions and give guidance to an ad hoc assessment of future topographically induced ice loss based on knowledge of the upstream fjord geometry. publishedVersion Article in Journal/Newspaper Ice Sheet Jakobshavn Jakobshavn isbræ The Cryosphere Tidewater University of Bergen: Bergen Open Research Archive (BORA-UiB) Jakobshavn Isbræ ENVELOPE(-49.917,-49.917,69.167,69.167) The Cryosphere 16 2 581 601 |
institution |
Open Polar |
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University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
description |
Retreat of marine outlet glaciers often initiates depletion of inland ice through dynamic adjustments of the upstream glacier. The local topography of a fjord may promote or inhibit such retreat, and therefore fjord geometry constitutes a critical control on ice sheet mass balance. To quantify the processes of ice–topography interactions and enhance the understanding of the dynamics involved, we analyze a multitude of topographic fjord settings and scenarios using the Ice-sheet and Sea-level System Model (ISSM). We systematically study glacier retreat through a variety of artificial fjord geometries and quantify the modeled dynamics directly in relation to topographic features. We find that retreat in an upstream-widening or upstream-deepening fjord does not necessarily promote retreat, as suggested by previous studies. Conversely, it may stabilize a glacier because converging ice flow towards a constriction enhances lateral and basal shear stress gradients. An upstream-narrowing or upstream-shoaling fjord, in turn, may promote retreat since fjord walls or bed provide little stability to the glacier where ice flow diverges. Furthermore, we identify distinct quantitative relationships directly linking grounding line discharge and retreat rate to fjord topography and transfer these results to a long-term study of the retreat of Jakobshavn Isbræ. These findings offer new perspectives on ice–topography interactions and give guidance to an ad hoc assessment of future topographically induced ice loss based on knowledge of the upstream fjord geometry. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Frank, Thomas Åkesson, Henning Fleurian, Basile de Morlighem, M. Nisancioglu, Kerim Hestnes |
spellingShingle |
Frank, Thomas Åkesson, Henning Fleurian, Basile de Morlighem, M. Nisancioglu, Kerim Hestnes Geometric controls of tidewater glacier dynamics |
author_facet |
Frank, Thomas Åkesson, Henning Fleurian, Basile de Morlighem, M. Nisancioglu, Kerim Hestnes |
author_sort |
Frank, Thomas |
title |
Geometric controls of tidewater glacier dynamics |
title_short |
Geometric controls of tidewater glacier dynamics |
title_full |
Geometric controls of tidewater glacier dynamics |
title_fullStr |
Geometric controls of tidewater glacier dynamics |
title_full_unstemmed |
Geometric controls of tidewater glacier dynamics |
title_sort |
geometric controls of tidewater glacier dynamics |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://hdl.handle.net/11250/2984317 https://doi.org/10.5194/tc-16-581-2022 |
long_lat |
ENVELOPE(-49.917,-49.917,69.167,69.167) |
geographic |
Jakobshavn Isbræ |
geographic_facet |
Jakobshavn Isbræ |
genre |
Ice Sheet Jakobshavn Jakobshavn isbræ The Cryosphere Tidewater |
genre_facet |
Ice Sheet Jakobshavn Jakobshavn isbræ The Cryosphere Tidewater |
op_source |
The Cryosphere 581-601 16 2 |
op_relation |
Notur/NorStore: nn4659k Norges forskningsråd: 302458 Norges forskningsråd: 287206 Notur/NorStore: ns4659k Notur/NorStore: nn9635k Notur/NorStore: ns9635k urn:issn:1994-0416 https://hdl.handle.net/11250/2984317 https://doi.org/10.5194/tc-16-581-2022 cristin:2003311 The Cryosphere. 2022, 16 (2), 581-601. |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright Author(s) 2022 |
op_doi |
https://doi.org/10.5194/tc-16-581-2022 |
container_title |
The Cryosphere |
container_volume |
16 |
container_issue |
2 |
container_start_page |
581 |
op_container_end_page |
601 |
_version_ |
1766031016896495616 |