Kinematic first-order calving law implies potential for abrupt ice-shelf retreat
Recently observed large-scale disintegration of Antarctic ice shelves has moved their fronts closer towards grounded ice. In response, ice-sheet discharge into the ocean has accelerated, contributing to global sea-level rise and emphasizing the importance of calving-front dynamics. The position of t...
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2012
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ftleibnizopen:oai:oai.leibnizopen.de:CvVD-IYBdbrxVwz6ftg3 2023-05-15T13:44:08+02:00 Kinematic first-order calving law implies potential for abrupt ice-shelf retreat Levermann, A. Albrecht, T. Winkelmann, R. Martin, M.A. Haseloff, M. Joughin, I. 2012 application/pdf https://doi.org/10.34657/1061 https://oa.tib.eu/renate/handle/123456789/681 eng eng München : European Geopyhsical Union CC BY 3.0 Unported https://creativecommons.org/licenses/by/3.0/ The Cryosphere, Volume 6, Issue 2, Page 273-286 discharge equation glacier retreat grounding line ice mechanics ice shelf iceberg calving kinematics mass transfer parameterization stress field 550 article Text 2012 ftleibnizopen https://doi.org/10.34657/1061 2023-03-20T00:14:02Z Recently observed large-scale disintegration of Antarctic ice shelves has moved their fronts closer towards grounded ice. In response, ice-sheet discharge into the ocean has accelerated, contributing to global sea-level rise and emphasizing the importance of calving-front dynamics. The position of the ice front strongly influences the stress field within the entire sheet-shelf-system and thereby the mass flow across the grounding line. While theories for an advance of the ice-front are readily available, no general rule exists for its retreat, making it difficult to incorporate the retreat in predictive models. Here we extract the first-order large-scale kinematic contribution to calving which is consistent with large-scale observation. We emphasize that the proposed equation does not constitute a comprehensive calving law but represents the first-order kinematic contribution which can and should be complemented by higher order contributions as well as the influence of potentially heterogeneous material properties of the ice. When applied as a calving law, the equation naturally incorporates the stabilizing effect of pinning points and inhibits ice shelf growth outside of embayments. It depends only on local ice properties which are, however, determined by the full topography of the ice shelf. In numerical simulations the parameterization reproduces multiple stable fronts as observed for the Larsen A and B Ice Shelves including abrupt transitions between them which may be caused by localized ice weaknesses. We also find multiple stable states of the Ross Ice Shelf at the gateway of the West Antarctic Ice Sheet with back stresses onto the sheet reduced by up to 90 % compared to the present state. publishedVersion Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Iceberg* Ross Ice Shelf The Cryosphere LeibnizOpen (The Leibniz Association) Antarctic West Antarctic Ice Sheet Ross Ice Shelf |
institution |
Open Polar |
collection |
LeibnizOpen (The Leibniz Association) |
op_collection_id |
ftleibnizopen |
language |
English |
topic |
discharge equation glacier retreat grounding line ice mechanics ice shelf iceberg calving kinematics mass transfer parameterization stress field 550 |
spellingShingle |
discharge equation glacier retreat grounding line ice mechanics ice shelf iceberg calving kinematics mass transfer parameterization stress field 550 Levermann, A. Albrecht, T. Winkelmann, R. Martin, M.A. Haseloff, M. Joughin, I. Kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
topic_facet |
discharge equation glacier retreat grounding line ice mechanics ice shelf iceberg calving kinematics mass transfer parameterization stress field 550 |
description |
Recently observed large-scale disintegration of Antarctic ice shelves has moved their fronts closer towards grounded ice. In response, ice-sheet discharge into the ocean has accelerated, contributing to global sea-level rise and emphasizing the importance of calving-front dynamics. The position of the ice front strongly influences the stress field within the entire sheet-shelf-system and thereby the mass flow across the grounding line. While theories for an advance of the ice-front are readily available, no general rule exists for its retreat, making it difficult to incorporate the retreat in predictive models. Here we extract the first-order large-scale kinematic contribution to calving which is consistent with large-scale observation. We emphasize that the proposed equation does not constitute a comprehensive calving law but represents the first-order kinematic contribution which can and should be complemented by higher order contributions as well as the influence of potentially heterogeneous material properties of the ice. When applied as a calving law, the equation naturally incorporates the stabilizing effect of pinning points and inhibits ice shelf growth outside of embayments. It depends only on local ice properties which are, however, determined by the full topography of the ice shelf. In numerical simulations the parameterization reproduces multiple stable fronts as observed for the Larsen A and B Ice Shelves including abrupt transitions between them which may be caused by localized ice weaknesses. We also find multiple stable states of the Ross Ice Shelf at the gateway of the West Antarctic Ice Sheet with back stresses onto the sheet reduced by up to 90 % compared to the present state. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Levermann, A. Albrecht, T. Winkelmann, R. Martin, M.A. Haseloff, M. Joughin, I. |
author_facet |
Levermann, A. Albrecht, T. Winkelmann, R. Martin, M.A. Haseloff, M. Joughin, I. |
author_sort |
Levermann, A. |
title |
Kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
title_short |
Kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
title_full |
Kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
title_fullStr |
Kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
title_full_unstemmed |
Kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
title_sort |
kinematic first-order calving law implies potential for abrupt ice-shelf retreat |
publisher |
München : European Geopyhsical Union |
publishDate |
2012 |
url |
https://doi.org/10.34657/1061 https://oa.tib.eu/renate/handle/123456789/681 |
geographic |
Antarctic West Antarctic Ice Sheet Ross Ice Shelf |
geographic_facet |
Antarctic West Antarctic Ice Sheet Ross Ice Shelf |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Iceberg* Ross Ice Shelf The Cryosphere |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Iceberg* Ross Ice Shelf The Cryosphere |
op_source |
The Cryosphere, Volume 6, Issue 2, Page 273-286 |
op_rights |
CC BY 3.0 Unported https://creativecommons.org/licenses/by/3.0/ |
op_doi |
https://doi.org/10.34657/1061 |
_version_ |
1766198040745476096 |