Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations
Calving is a major means of ice discharge of the Antarctic and Greenland Ice Sheets. The breaking off of icebergs changes the ice front configuration of marine terminating glaciers, which affects the stress regime of their upstream areas. Recent observations show the close correlation between the ic...
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COPERNICUS GESELLSCHAFT MBH
2015
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ftawi:oai:epic.awi.de:38877 2023-05-15T13:40:27+02:00 Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations Bondzio, Johannes Heinrich Seroussi, Helene Morlighem, Mathieu Kleiner, Thomas Rückamp, Martin Humbert, Angelika Larour, Eric 2015-10-01 application/pdf https://epic.awi.de/id/eprint/38877/ https://epic.awi.de/id/eprint/38877/1/tcd-9-5485-2015.pdf https://doi.org/10.5194/tcd-9-5485-2015 https://hdl.handle.net/10013/epic.46147 https://hdl.handle.net/10013/epic.46147.d001 unknown COPERNICUS GESELLSCHAFT MBH https://epic.awi.de/id/eprint/38877/1/tcd-9-5485-2015.pdf https://hdl.handle.net/10013/epic.46147.d001 Bondzio, J. H. , Seroussi, H. , Morlighem, M. , Kleiner, T. orcid:0000-0001-7825-5765 , Rückamp, M. orcid:0000-0003-2512-7238 , Humbert, A. and Larour, E. (2015) Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations , The Cryosphere Discussions, 9 (5), pp. 5485-5520 . doi:10.5194/tcd-9-5485-2015 <https://doi.org/10.5194/tcd-9-5485-2015> , hdl:10013/epic.46147 EPIC3The Cryosphere Discussions, COPERNICUS GESELLSCHAFT MBH, 9(5), pp. 5485-5520, ISSN: 1994-0440 Article notRev 2015 ftawi https://doi.org/10.5194/tcd-9-5485-2015 2021-12-24T15:40:48Z Calving is a major means of ice discharge of the Antarctic and Greenland Ice Sheets. The breaking off of icebergs changes the ice front configuration of marine terminating glaciers, which affects the stress regime of their upstream areas. Recent observations show the close correlation between the ice front position and the behaviour of many outlet glaciers. However, modelling of a glacier subject to calving poses various challenges. No universal calving rate parametrisation is known, and tracking of a moving ice front and the related boundary conditions in two or three spatial dimensions is non-trivial. Here, we present the theoretical and technical framework for a Level-Set Method, an implicit boundary tracking scheme, which we implemented into the Ice Sheet System Model (ISSM). The scheme allows us to study the dynamic response of a drainage basin to user-defined front ablation rates. We apply the method in a suite of experiments to Jakobshavn Isbræ, a major marine terminating outlet glacier of the western Greenland Ice Sheet. The model robustly reproduces the high sensitivity of the glacier to frontal ablation in form of calving. We find that enhanced calving is able to trigger significant acceleration of the ice stream. Upstream acceleration is sustained through a combination of various feedback mechanisms. However, lateral stress and ice influx into the trough are able to stabilise the ice stream. This study contributes to the present discussion on causes and effects of the continued changes occurring at Jakobshavn Isbræ, and emphasises that the incorporation of seasonal calving and dynamic lateral effects is key for realistic model projections of future global sea level rise on centennial time scales. Article in Journal/Newspaper Antarc* Antarctic glacier Greenland Ice Sheet Iceberg* Jakobshavn Jakobshavn isbræ The Cryosphere The Cryosphere Discussions Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic The Antarctic Greenland Jakobshavn Isbræ ENVELOPE(-49.917,-49.917,69.167,69.167) |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Calving is a major means of ice discharge of the Antarctic and Greenland Ice Sheets. The breaking off of icebergs changes the ice front configuration of marine terminating glaciers, which affects the stress regime of their upstream areas. Recent observations show the close correlation between the ice front position and the behaviour of many outlet glaciers. However, modelling of a glacier subject to calving poses various challenges. No universal calving rate parametrisation is known, and tracking of a moving ice front and the related boundary conditions in two or three spatial dimensions is non-trivial. Here, we present the theoretical and technical framework for a Level-Set Method, an implicit boundary tracking scheme, which we implemented into the Ice Sheet System Model (ISSM). The scheme allows us to study the dynamic response of a drainage basin to user-defined front ablation rates. We apply the method in a suite of experiments to Jakobshavn Isbræ, a major marine terminating outlet glacier of the western Greenland Ice Sheet. The model robustly reproduces the high sensitivity of the glacier to frontal ablation in form of calving. We find that enhanced calving is able to trigger significant acceleration of the ice stream. Upstream acceleration is sustained through a combination of various feedback mechanisms. However, lateral stress and ice influx into the trough are able to stabilise the ice stream. This study contributes to the present discussion on causes and effects of the continued changes occurring at Jakobshavn Isbræ, and emphasises that the incorporation of seasonal calving and dynamic lateral effects is key for realistic model projections of future global sea level rise on centennial time scales. |
format |
Article in Journal/Newspaper |
author |
Bondzio, Johannes Heinrich Seroussi, Helene Morlighem, Mathieu Kleiner, Thomas Rückamp, Martin Humbert, Angelika Larour, Eric |
spellingShingle |
Bondzio, Johannes Heinrich Seroussi, Helene Morlighem, Mathieu Kleiner, Thomas Rückamp, Martin Humbert, Angelika Larour, Eric Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations |
author_facet |
Bondzio, Johannes Heinrich Seroussi, Helene Morlighem, Mathieu Kleiner, Thomas Rückamp, Martin Humbert, Angelika Larour, Eric |
author_sort |
Bondzio, Johannes Heinrich |
title |
Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations |
title_short |
Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations |
title_full |
Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations |
title_fullStr |
Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations |
title_full_unstemmed |
Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations |
title_sort |
modelling the dynamic response of jakobshavn isbræ, west greenland, to calving rate perturbations |
publisher |
COPERNICUS GESELLSCHAFT MBH |
publishDate |
2015 |
url |
https://epic.awi.de/id/eprint/38877/ https://epic.awi.de/id/eprint/38877/1/tcd-9-5485-2015.pdf https://doi.org/10.5194/tcd-9-5485-2015 https://hdl.handle.net/10013/epic.46147 https://hdl.handle.net/10013/epic.46147.d001 |
long_lat |
ENVELOPE(-49.917,-49.917,69.167,69.167) |
geographic |
Antarctic The Antarctic Greenland Jakobshavn Isbræ |
geographic_facet |
Antarctic The Antarctic Greenland Jakobshavn Isbræ |
genre |
Antarc* Antarctic glacier Greenland Ice Sheet Iceberg* Jakobshavn Jakobshavn isbræ The Cryosphere The Cryosphere Discussions |
genre_facet |
Antarc* Antarctic glacier Greenland Ice Sheet Iceberg* Jakobshavn Jakobshavn isbræ The Cryosphere The Cryosphere Discussions |
op_source |
EPIC3The Cryosphere Discussions, COPERNICUS GESELLSCHAFT MBH, 9(5), pp. 5485-5520, ISSN: 1994-0440 |
op_relation |
https://epic.awi.de/id/eprint/38877/1/tcd-9-5485-2015.pdf https://hdl.handle.net/10013/epic.46147.d001 Bondzio, J. H. , Seroussi, H. , Morlighem, M. , Kleiner, T. orcid:0000-0001-7825-5765 , Rückamp, M. orcid:0000-0003-2512-7238 , Humbert, A. and Larour, E. (2015) Modelling the dynamic response of Jakobshavn Isbræ, West Greenland, to calving rate perturbations , The Cryosphere Discussions, 9 (5), pp. 5485-5520 . doi:10.5194/tcd-9-5485-2015 <https://doi.org/10.5194/tcd-9-5485-2015> , hdl:10013/epic.46147 |
op_doi |
https://doi.org/10.5194/tcd-9-5485-2015 |
_version_ |
1766134698511171584 |