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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ftdoajarticles:oai:doaj.org/article:3c9275f16bd243419250f50ad74bb63f 2023-05-15T16:21:28+02:00 Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry N. Steiger K. H. Nisancioglu H. Åkesson B. de Fleurian F. M. Nick 2018-07-01T00:00:00Z https://doi.org/10.5194/tc-12-2249-2018 https://doaj.org/article/3c9275f16bd243419250f50ad74bb63f EN eng Copernicus Publications https://www.the-cryosphere.net/12/2249/2018/tc-12-2249-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-2249-2018 1994-0416 1994-0424 https://doaj.org/article/3c9275f16bd243419250f50ad74bb63f The Cryosphere, Vol 12, Pp 2249-2266 (2018) Environmental sciences GE1-350 Geology QE1-996.5 article 2018 ftdoajarticles https://doi.org/10.5194/tc-12-2249-2018 2022-12-31T04:38:57Z 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. Article in Journal/Newspaper glacier Greenland Jakobshavn Jakobshavn isbræ Sea ice The Cryosphere Directory of Open Access Journals: DOAJ Articles Greenland Jakobshavn Isbræ ENVELOPE(-49.917,-49.917,69.167,69.167) The Cryosphere 12 7 2249 2266 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 N. Steiger K. H. Nisancioglu H. Åkesson B. de Fleurian F. M. Nick Simulated retreat of Jakobshavn Isbræ since the Little Ice Age controlled by geometry |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
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. |
format |
Article in Journal/Newspaper |
author |
N. Steiger K. H. Nisancioglu H. Åkesson B. de Fleurian F. M. Nick |
author_facet |
N. Steiger K. H. Nisancioglu H. Åkesson B. de Fleurian F. M. Nick |
author_sort |
N. Steiger |
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 |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-2249-2018 https://doaj.org/article/3c9275f16bd243419250f50ad74bb63f |
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, Vol 12, Pp 2249-2266 (2018) |
op_relation |
https://www.the-cryosphere.net/12/2249/2018/tc-12-2249-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-2249-2018 1994-0416 1994-0424 https://doaj.org/article/3c9275f16bd243419250f50ad74bb63f |
op_doi |
https://doi.org/10.5194/tc-12-2249-2018 |
container_title |
The Cryosphere |
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12 |
container_issue |
7 |
container_start_page |
2249 |
op_container_end_page |
2266 |
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1766009468550643712 |