Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica
The bed of the West Antarctic Ice Sheet is, in places, more than 1.5 km below sea level(1,2). It has been suggested that a positive ice-loss feedback may occur when an ice sheet's grounding line retreats across a deepening bed(1-3). Applied to the West Antarctic Ice Sheet, this process could po...
Published in: | Nature Geoscience |
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Format: | Article in Journal/Newspaper |
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2012
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Online Access: | https://hdl.handle.net/1983/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd https://research-information.bris.ac.uk/en/publications/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd https://doi.org/10.1038/NGEO1468 http://www.nature.com/ngeo/journal/v5/n6/full/ngeo1468.html |
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ftubristolcris:oai:research-information.bris.ac.uk:publications/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd 2024-05-12T07:52:51+00:00 Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica Ross, Neil Bingham, Robert G. Corr, Hugh F. J. Ferraccioli, Fausto Jordan, Tom A. Le Brocq, Anne Rippin, David M. Young, Duncan Blankenship, Donald D. Siegert, Martin J. 2012-06 https://hdl.handle.net/1983/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd https://research-information.bris.ac.uk/en/publications/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd https://doi.org/10.1038/NGEO1468 http://www.nature.com/ngeo/journal/v5/n6/full/ngeo1468.html eng eng https://research-information.bris.ac.uk/en/publications/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd info:eu-repo/semantics/restrictedAccess Ross , N , Bingham , R G , Corr , H F J , Ferraccioli , F , Jordan , T A , Le Brocq , A , Rippin , D M , Young , D , Blankenship , D D & Siegert , M J 2012 , ' Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica ' , Nature Geoscience , vol. 5 , no. 6 , pp. 393-396 . https://doi.org/10.1038/NGEO1468 article 2012 ftubristolcris https://doi.org/10.1038/NGEO1468 2024-04-17T14:15:14Z The bed of the West Antarctic Ice Sheet is, in places, more than 1.5 km below sea level(1,2). It has been suggested that a positive ice-loss feedback may occur when an ice sheet's grounding line retreats across a deepening bed(1-3). Applied to the West Antarctic Ice Sheet, this process could potentially raise global sea level(4) by more than 3 m. Hitherto, attention has focussed on changes at the Siple Coast(5-7) and Amundsen Sea embayment(8-10) sectors of West Antarctica. Here, we present radio-echo sounding information from the ice sheet's third sector, the Weddell Sea embayment, that reveals a large subglacial basin immediately upstream of the grounding line. The reverse bed slope is steep, with about 400 m of decline over 40 km. The basin floor is smooth and flat, with little small-scale topography that would delay retreat, indicating that it has been covered with marine sediment(5,11) and was previously deglaciated. Upstream of the basin, well-defined glacially carved fjords with bars at their mouths testify to the position of a former ice margin about 200 km inland from the present margin. Evidence so far suggests that the Weddell Sea sector of the West Antarctic Ice Sheet has been stable, but in the light of our data we propose that the region could be near a physical threshold of substantial change. Article in Journal/Newspaper Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Weddell Sea West Antarctica University of Bristol: Bristol Research Amundsen Sea Antarctic Siple ENVELOPE(-83.917,-83.917,-75.917,-75.917) Siple Coast ENVELOPE(-155.000,-155.000,-82.000,-82.000) Weddell Weddell Sea West Antarctic Ice Sheet West Antarctica Nature Geoscience 5 6 393 396 |
institution |
Open Polar |
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University of Bristol: Bristol Research |
op_collection_id |
ftubristolcris |
language |
English |
description |
The bed of the West Antarctic Ice Sheet is, in places, more than 1.5 km below sea level(1,2). It has been suggested that a positive ice-loss feedback may occur when an ice sheet's grounding line retreats across a deepening bed(1-3). Applied to the West Antarctic Ice Sheet, this process could potentially raise global sea level(4) by more than 3 m. Hitherto, attention has focussed on changes at the Siple Coast(5-7) and Amundsen Sea embayment(8-10) sectors of West Antarctica. Here, we present radio-echo sounding information from the ice sheet's third sector, the Weddell Sea embayment, that reveals a large subglacial basin immediately upstream of the grounding line. The reverse bed slope is steep, with about 400 m of decline over 40 km. The basin floor is smooth and flat, with little small-scale topography that would delay retreat, indicating that it has been covered with marine sediment(5,11) and was previously deglaciated. Upstream of the basin, well-defined glacially carved fjords with bars at their mouths testify to the position of a former ice margin about 200 km inland from the present margin. Evidence so far suggests that the Weddell Sea sector of the West Antarctic Ice Sheet has been stable, but in the light of our data we propose that the region could be near a physical threshold of substantial change. |
format |
Article in Journal/Newspaper |
author |
Ross, Neil Bingham, Robert G. Corr, Hugh F. J. Ferraccioli, Fausto Jordan, Tom A. Le Brocq, Anne Rippin, David M. Young, Duncan Blankenship, Donald D. Siegert, Martin J. |
spellingShingle |
Ross, Neil Bingham, Robert G. Corr, Hugh F. J. Ferraccioli, Fausto Jordan, Tom A. Le Brocq, Anne Rippin, David M. Young, Duncan Blankenship, Donald D. Siegert, Martin J. Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica |
author_facet |
Ross, Neil Bingham, Robert G. Corr, Hugh F. J. Ferraccioli, Fausto Jordan, Tom A. Le Brocq, Anne Rippin, David M. Young, Duncan Blankenship, Donald D. Siegert, Martin J. |
author_sort |
Ross, Neil |
title |
Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica |
title_short |
Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica |
title_full |
Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica |
title_fullStr |
Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica |
title_full_unstemmed |
Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica |
title_sort |
steep reverse bed slope at the grounding line of the weddell sea sector in west antarctica |
publishDate |
2012 |
url |
https://hdl.handle.net/1983/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd https://research-information.bris.ac.uk/en/publications/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd https://doi.org/10.1038/NGEO1468 http://www.nature.com/ngeo/journal/v5/n6/full/ngeo1468.html |
long_lat |
ENVELOPE(-83.917,-83.917,-75.917,-75.917) ENVELOPE(-155.000,-155.000,-82.000,-82.000) |
geographic |
Amundsen Sea Antarctic Siple Siple Coast Weddell Weddell Sea West Antarctic Ice Sheet West Antarctica |
geographic_facet |
Amundsen Sea Antarctic Siple Siple Coast Weddell Weddell Sea West Antarctic Ice Sheet West Antarctica |
genre |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Weddell Sea West Antarctica |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Weddell Sea West Antarctica |
op_source |
Ross , N , Bingham , R G , Corr , H F J , Ferraccioli , F , Jordan , T A , Le Brocq , A , Rippin , D M , Young , D , Blankenship , D D & Siegert , M J 2012 , ' Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica ' , Nature Geoscience , vol. 5 , no. 6 , pp. 393-396 . https://doi.org/10.1038/NGEO1468 |
op_relation |
https://research-information.bris.ac.uk/en/publications/613dfad2-c4d7-4e9b-a21c-89e20e03d0fd |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1038/NGEO1468 |
container_title |
Nature Geoscience |
container_volume |
5 |
container_issue |
6 |
container_start_page |
393 |
op_container_end_page |
396 |
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1798838156305367040 |