Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin
©2018. American Geophysical Union. All Rights Reserved. Rapid change now underway on Thwaites Glacier (TG) raises concern that a threshold for unstoppable grounding line retreat has been or is about to be crossed. We use a high-resolution ice sheet model to examine the mechanics of TG self-sustained...
Published in: | Geophysical Research Letters |
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Language: | English |
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ftcdlib:qt0s75n929 2023-05-15T16:40:25+02:00 Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin Waibel, MS Hulbe, CL Jackson, CS Martin, DF 809 - 816 2018-01-28 application/pdf http://www.escholarship.org/uc/item/0s75n929 english eng eScholarship, University of California qt0s75n929 http://www.escholarship.org/uc/item/0s75n929 public Waibel, MS; Hulbe, CL; Jackson, CS; & Martin, DF. (2018). Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin. Geophysical Research Letters, 45(2), 809 - 816. doi:10.1002/2017GL076470. Lawrence Berkeley National Laboratory: Retrieved from: http://www.escholarship.org/uc/item/0s75n929 article 2018 ftcdlib https://doi.org/10.1002/2017GL076470 2019-04-12T22:51:51Z ©2018. American Geophysical Union. All Rights Reserved. Rapid change now underway on Thwaites Glacier (TG) raises concern that a threshold for unstoppable grounding line retreat has been or is about to be crossed. We use a high-resolution ice sheet model to examine the mechanics of TG self-sustained retreat by nudging the grounding line just past the point of instability. We find that by modifying surface slope in the region of the grounding line, the rate of the forcing dictates the rate of retreat, even after the external forcing is removed. Grounding line retreats that begin faster proceed more rapidly because the shorter time interval for the grounding line to erode into the grounded ice sheet means relatively thicker ice and larger driving stress upstream of the boundary. Retreat is sensitive to short-duration re-advances associated with reduced external forcing where the bathymetry allows regrounding, even when an instability is invoked. Article in Journal/Newspaper Ice Sheet Thwaites Glacier University of California: eScholarship Thwaites Glacier ENVELOPE(-106.750,-106.750,-75.500,-75.500) Geophysical Research Letters 45 2 809 816 |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
description |
©2018. American Geophysical Union. All Rights Reserved. Rapid change now underway on Thwaites Glacier (TG) raises concern that a threshold for unstoppable grounding line retreat has been or is about to be crossed. We use a high-resolution ice sheet model to examine the mechanics of TG self-sustained retreat by nudging the grounding line just past the point of instability. We find that by modifying surface slope in the region of the grounding line, the rate of the forcing dictates the rate of retreat, even after the external forcing is removed. Grounding line retreats that begin faster proceed more rapidly because the shorter time interval for the grounding line to erode into the grounded ice sheet means relatively thicker ice and larger driving stress upstream of the boundary. Retreat is sensitive to short-duration re-advances associated with reduced external forcing where the bathymetry allows regrounding, even when an instability is invoked. |
format |
Article in Journal/Newspaper |
author |
Waibel, MS Hulbe, CL Jackson, CS Martin, DF |
spellingShingle |
Waibel, MS Hulbe, CL Jackson, CS Martin, DF Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin |
author_facet |
Waibel, MS Hulbe, CL Jackson, CS Martin, DF |
author_sort |
Waibel, MS |
title |
Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin |
title_short |
Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin |
title_full |
Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin |
title_fullStr |
Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin |
title_full_unstemmed |
Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin |
title_sort |
rate of mass loss across the instability threshold for thwaites glacier determines rate of mass loss for entire basin |
publisher |
eScholarship, University of California |
publishDate |
2018 |
url |
http://www.escholarship.org/uc/item/0s75n929 |
op_coverage |
809 - 816 |
long_lat |
ENVELOPE(-106.750,-106.750,-75.500,-75.500) |
geographic |
Thwaites Glacier |
geographic_facet |
Thwaites Glacier |
genre |
Ice Sheet Thwaites Glacier |
genre_facet |
Ice Sheet Thwaites Glacier |
op_source |
Waibel, MS; Hulbe, CL; Jackson, CS; & Martin, DF. (2018). Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin. Geophysical Research Letters, 45(2), 809 - 816. doi:10.1002/2017GL076470. Lawrence Berkeley National Laboratory: Retrieved from: http://www.escholarship.org/uc/item/0s75n929 |
op_relation |
qt0s75n929 http://www.escholarship.org/uc/item/0s75n929 |
op_rights |
public |
op_doi |
https://doi.org/10.1002/2017GL076470 |
container_title |
Geophysical Research Letters |
container_volume |
45 |
container_issue |
2 |
container_start_page |
809 |
op_container_end_page |
816 |
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1766030811677589504 |