Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry
Rapid retreat of Greenland's marine-terminating glaciers coincides with regional warming trends, which have broadly been used to explain these rapid changes. However, outlet glaciers within similar climate regimes experience widely contrasting retreat patterns, suggesting that the local fjord g...
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Online Access: | https://hdl.handle.net/1956/19295 https://doi.org/10.5194/tc-12-2249-2018 |
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ftunivbergen:oai:bora.uib.no:1956/19295 2023-05-15T16:21:27+02:00 Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry Steiger, Nadine Nisancioglu, Kerim Hestnes Åkesson, Henning de Fleurian, Basile Nick, Faezeh M. 2018-07-12T09:45:52Z application/pdf https://hdl.handle.net/1956/19295 https://doi.org/10.5194/tc-12-2249-2018 eng eng European Geosciences Union https://doi.org/10.5194/tc-12-2249-2018 Notur/NorStore: NN4659K Norges forskningsråd: 229788 Norges forskningsråd: 246929 EC/FP7: 610055 urn:issn:1994-0424 urn:issn:1994-0416 https://hdl.handle.net/1956/19295 cristin:1596879 Attribution CC BY http://creativecommons.org/licenses/by/4.0/ Copyright The Author(s) 2018 The Cryosphere Peer reviewed Journal article 2018 ftunivbergen https://doi.org/10.5194/tc-12-2249-2018 2023-03-14T17:44:47Z Rapid retreat of Greenland's marine-terminating glaciers coincides with regional warming trends, which have broadly been used to explain these rapid changes. However, outlet glaciers within similar climate regimes experience widely contrasting retreat patterns, suggesting that the local fjord geometry could be an important additional factor. To assess the relative role of climate and fjord geometry, we use the retreat history of Jakobshavn Isbræ, West Greenland, since the Little Ice Age (LIA) maximum in 1850 as a baseline for the parameterization of a depth- and width-integrated ice flow model. The impact of fjord geometry is isolated by using a linearly increasing climate forcing since the LIA and testing a range of simplified geometries. We find that the total length of retreat is determined by external factors – such as hydrofracturing, submarine melt and buttressing by sea ice – whereas the retreat pattern is governed by the fjord geometry. Narrow and shallow areas provide pinning points and cause delayed but rapid retreat without additional climate warming, after decades of grounding line stability. We suggest that these geometric pinning points may be used to locate potential sites for moraine formation and to predict the long-term response of the glacier. As a consequence, to assess the impact of climate on the retreat history of a glacier, each system has to be analyzed with knowledge of its historic retreat and the local fjord geometry. publishedVersion Article in Journal/Newspaper glacier Greenland Jakobshavn Jakobshavn isbræ Sea ice The Cryosphere University of Bergen: Bergen Open Research Archive (BORA-UiB) Greenland Jakobshavn Isbræ ENVELOPE(-49.917,-49.917,69.167,69.167) The Cryosphere 12 7 2249 2266 |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
description |
Rapid retreat of Greenland's marine-terminating glaciers coincides with regional warming trends, which have broadly been used to explain these rapid changes. However, outlet glaciers within similar climate regimes experience widely contrasting retreat patterns, suggesting that the local fjord geometry could be an important additional factor. To assess the relative role of climate and fjord geometry, we use the retreat history of Jakobshavn Isbræ, West Greenland, since the Little Ice Age (LIA) maximum in 1850 as a baseline for the parameterization of a depth- and width-integrated ice flow model. The impact of fjord geometry is isolated by using a linearly increasing climate forcing since the LIA and testing a range of simplified geometries. We find that the total length of retreat is determined by external factors – such as hydrofracturing, submarine melt and buttressing by sea ice – whereas the retreat pattern is governed by the fjord geometry. Narrow and shallow areas provide pinning points and cause delayed but rapid retreat without additional climate warming, after decades of grounding line stability. We suggest that these geometric pinning points may be used to locate potential sites for moraine formation and to predict the long-term response of the glacier. As a consequence, to assess the impact of climate on the retreat history of a glacier, each system has to be analyzed with knowledge of its historic retreat and the local fjord geometry. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Steiger, Nadine Nisancioglu, Kerim Hestnes Åkesson, Henning de Fleurian, Basile Nick, Faezeh M. |
spellingShingle |
Steiger, Nadine Nisancioglu, Kerim Hestnes Åkesson, Henning de Fleurian, Basile Nick, Faezeh M. Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
author_facet |
Steiger, Nadine Nisancioglu, Kerim Hestnes Åkesson, Henning de Fleurian, Basile Nick, Faezeh M. |
author_sort |
Steiger, Nadine |
title |
Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
title_short |
Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
title_full |
Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
title_fullStr |
Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
title_full_unstemmed |
Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
title_sort |
simulated retreat of jakobshavn isbræ since the little ice age controlled by geometry |
publisher |
European Geosciences Union |
publishDate |
2018 |
url |
https://hdl.handle.net/1956/19295 https://doi.org/10.5194/tc-12-2249-2018 |
long_lat |
ENVELOPE(-49.917,-49.917,69.167,69.167) |
geographic |
Greenland Jakobshavn Isbræ |
geographic_facet |
Greenland Jakobshavn Isbræ |
genre |
glacier Greenland Jakobshavn Jakobshavn isbræ Sea ice The Cryosphere |
genre_facet |
glacier Greenland Jakobshavn Jakobshavn isbræ Sea ice The Cryosphere |
op_source |
The Cryosphere |
op_relation |
https://doi.org/10.5194/tc-12-2249-2018 Notur/NorStore: NN4659K Norges forskningsråd: 229788 Norges forskningsråd: 246929 EC/FP7: 610055 urn:issn:1994-0424 urn:issn:1994-0416 https://hdl.handle.net/1956/19295 cristin:1596879 |
op_rights |
Attribution CC BY http://creativecommons.org/licenses/by/4.0/ Copyright The Author(s) 2018 |
op_doi |
https://doi.org/10.5194/tc-12-2249-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
7 |
container_start_page |
2249 |
op_container_end_page |
2266 |
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1766009451973705728 |