Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet.
The configuration of subglacial meltwater is a critical control on ice sheet dynamics, and the presence of pressurized water distributed across the bed can induce dynamic instabilities. However, this process can be offset by efficient evacuation of water within large subglacial channels, and drainag...
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Geological Society of America
2014
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Online Access: | http://dro.dur.ac.uk/11724/ http://dro.dur.ac.uk/11724/1/11724.pdf http://dro.dur.ac.uk/11724/2/11724P.pdf https://doi.org/10.1130/G35092.1 |
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ftunivdurham:oai:dro.dur.ac.uk.OAI2:11724 2023-05-15T16:29:36+02:00 Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. Storrar, R.D. Stokes, C.R. Evans, D.J.A. 2014-01-10 application/pdf http://dro.dur.ac.uk/11724/ http://dro.dur.ac.uk/11724/1/11724.pdf http://dro.dur.ac.uk/11724/2/11724P.pdf https://doi.org/10.1130/G35092.1 unknown Geological Society of America dro:11724 issn:0091-7613 issn: 1943-2682 doi:10.1130/G35092.1 http://dro.dur.ac.uk/11724/ http://dx.doi.org/10.1130/G35092.1 http://dro.dur.ac.uk/11724/1/11724.pdf http://dro.dur.ac.uk/11724/2/11724P.pdf © 2014 Geological Society of America. Gold Open Access: This paper is published under the terms of the CC-BY license CC-BY Geology, 2014, Vol.42(3), pp.239-242 [Peer Reviewed Journal] Article PeerReviewed 2014 ftunivdurham https://doi.org/10.1130/G35092.1 2020-08-27T22:21:54Z The configuration of subglacial meltwater is a critical control on ice sheet dynamics, and the presence of pressurized water distributed across the bed can induce dynamic instabilities. However, this process can be offset by efficient evacuation of water within large subglacial channels, and drainage systems beneath alpine glaciers have been shown to become increasingly channelized throughout the melt season in response to the increased production of meltwater. This seasonal evolution has recently been inferred beneath outlet glaciers of the Greenland Ice Sheet, but the extent to which this process occurs across much larger spatial and temporal scales is largely unknown, introducing considerable uncertainty about the evolution of subglacial drainage networks at the ice sheet scale and associated ice sheet dynamics. This paper uses an unprecedented data set of over 20,000 eskers to reconstruct the evolution of channelized meltwater systems during the final deglaciation of the Laurentide Ice Sheet (13–7 kyr B.P.). We demonstrate that eskers become more frequent during deglaciation and that this coincides with periods of increased rates of ice margin recession and climatic warming. Such behavior is reminiscent of the seasonal evolution of drainage systems observed in smaller glaciers and implies that channelized drainage became increasingly important during deglaciation. An important corollary is that the area of the bed subjected to a less efficient pressurized drainage system decreased, which may have precluded dynamic instabilities, such as surging or ice streaming. Article in Journal/Newspaper Greenland Ice Sheet Durham University: Durham Research Online Greenland Geology 42 3 239 242 |
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Open Polar |
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Durham University: Durham Research Online |
op_collection_id |
ftunivdurham |
language |
unknown |
description |
The configuration of subglacial meltwater is a critical control on ice sheet dynamics, and the presence of pressurized water distributed across the bed can induce dynamic instabilities. However, this process can be offset by efficient evacuation of water within large subglacial channels, and drainage systems beneath alpine glaciers have been shown to become increasingly channelized throughout the melt season in response to the increased production of meltwater. This seasonal evolution has recently been inferred beneath outlet glaciers of the Greenland Ice Sheet, but the extent to which this process occurs across much larger spatial and temporal scales is largely unknown, introducing considerable uncertainty about the evolution of subglacial drainage networks at the ice sheet scale and associated ice sheet dynamics. This paper uses an unprecedented data set of over 20,000 eskers to reconstruct the evolution of channelized meltwater systems during the final deglaciation of the Laurentide Ice Sheet (13–7 kyr B.P.). We demonstrate that eskers become more frequent during deglaciation and that this coincides with periods of increased rates of ice margin recession and climatic warming. Such behavior is reminiscent of the seasonal evolution of drainage systems observed in smaller glaciers and implies that channelized drainage became increasingly important during deglaciation. An important corollary is that the area of the bed subjected to a less efficient pressurized drainage system decreased, which may have precluded dynamic instabilities, such as surging or ice streaming. |
format |
Article in Journal/Newspaper |
author |
Storrar, R.D. Stokes, C.R. Evans, D.J.A. |
spellingShingle |
Storrar, R.D. Stokes, C.R. Evans, D.J.A. Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. |
author_facet |
Storrar, R.D. Stokes, C.R. Evans, D.J.A. |
author_sort |
Storrar, R.D. |
title |
Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. |
title_short |
Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. |
title_full |
Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. |
title_fullStr |
Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. |
title_full_unstemmed |
Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. |
title_sort |
increased channelization of subglacial drainage during deglaciation of the laurentide ice sheet. |
publisher |
Geological Society of America |
publishDate |
2014 |
url |
http://dro.dur.ac.uk/11724/ http://dro.dur.ac.uk/11724/1/11724.pdf http://dro.dur.ac.uk/11724/2/11724P.pdf https://doi.org/10.1130/G35092.1 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
Geology, 2014, Vol.42(3), pp.239-242 [Peer Reviewed Journal] |
op_relation |
dro:11724 issn:0091-7613 issn: 1943-2682 doi:10.1130/G35092.1 http://dro.dur.ac.uk/11724/ http://dx.doi.org/10.1130/G35092.1 http://dro.dur.ac.uk/11724/1/11724.pdf http://dro.dur.ac.uk/11724/2/11724P.pdf |
op_rights |
© 2014 Geological Society of America. Gold Open Access: This paper is published under the terms of the CC-BY license |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1130/G35092.1 |
container_title |
Geology |
container_volume |
42 |
container_issue |
3 |
container_start_page |
239 |
op_container_end_page |
242 |
_version_ |
1766019307735613440 |