An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier.
Seasonal variations in ice motion have been observed at several polythermal ice masses across the High Arctic, including the Greenland Ice Sheet. However, such variations in ice motion and their possible driving mechanisms are rarely incorporated in models of the response of High Arctic ice masses t...
Published in: | Journal of Geophysical Research |
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American Geophysical Union
2008
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ftnerc:oai:nora.nerc.ac.uk:3726 2023-05-15T14:25:49+02:00 An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. Bingham, Robert G. Hubbard, Alun L. Nienow, Peter W. Sharp, Martin J. 2008 text http://nora.nerc.ac.uk/id/eprint/3726/ https://nora.nerc.ac.uk/id/eprint/3726/1/2007JF000832_bingham.pdf http://www.agu.org/pubs/crossref/2008/2007JF000832.shtml https://doi.org/10.1029/2007JF000832 en eng American Geophysical Union https://nora.nerc.ac.uk/id/eprint/3726/1/2007JF000832_bingham.pdf Bingham, Robert G.; Hubbard, Alun L.; Nienow, Peter W.; Sharp, Martin J. 2008 An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. Journal of Geophysical Research, 113 (F2), F02006. 13, pp. https://doi.org/10.1029/2007JF000832 <https://doi.org/10.1029/2007JF000832> Glaciology Publication - Article PeerReviewed 2008 ftnerc https://doi.org/10.1029/2007JF000832 2023-02-04T19:22:26Z Seasonal variations in ice motion have been observed at several polythermal ice masses across the High Arctic, including the Greenland Ice Sheet. However, such variations in ice motion and their possible driving mechanisms are rarely incorporated in models of the response of High Arctic ice masses to predicted climate warming. Here we use a three-dimensional finite difference flow model, constrained by field data, to investigate seasonal variations in the distribution of basal sliding at polythermal John Evans Glacier, Ellesmere Island, Canada. Our results suggest that speedups observed at the surface during the melt season result directly from changes in rates of basal motion. They also suggest that stress gradient coupling is ineffective at transmitting basal motion anomalies to the upper part of the glacier, in contrast to findings from an earlier flow line study at the same glacier. We suggest that stress gradient coupling is limited through the effect of high drag imposed by a partially frozen bed and friction induced by valley walls and significant topographic pinning points. Our findings imply that stress gradient coupling may play a limited role in transmitting supraglacially forced basal motion anomalies through Arctic valley and outlet glaciers with complex topographic settings and highlight the importance of dynamically incorporating basal motion into models predicting the response of the Arctic's land ice to climate change. Article in Journal/Newspaper Arctic Arctic Climate change Ellesmere Island glacier glacier* Greenland Ice Sheet Natural Environment Research Council: NERC Open Research Archive Arctic Ellesmere Island Canada Greenland John Evans Glacier ENVELOPE(-74.079,-74.079,79.646,79.646) Journal of Geophysical Research 113 F2 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Glaciology |
spellingShingle |
Glaciology Bingham, Robert G. Hubbard, Alun L. Nienow, Peter W. Sharp, Martin J. An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. |
topic_facet |
Glaciology |
description |
Seasonal variations in ice motion have been observed at several polythermal ice masses across the High Arctic, including the Greenland Ice Sheet. However, such variations in ice motion and their possible driving mechanisms are rarely incorporated in models of the response of High Arctic ice masses to predicted climate warming. Here we use a three-dimensional finite difference flow model, constrained by field data, to investigate seasonal variations in the distribution of basal sliding at polythermal John Evans Glacier, Ellesmere Island, Canada. Our results suggest that speedups observed at the surface during the melt season result directly from changes in rates of basal motion. They also suggest that stress gradient coupling is ineffective at transmitting basal motion anomalies to the upper part of the glacier, in contrast to findings from an earlier flow line study at the same glacier. We suggest that stress gradient coupling is limited through the effect of high drag imposed by a partially frozen bed and friction induced by valley walls and significant topographic pinning points. Our findings imply that stress gradient coupling may play a limited role in transmitting supraglacially forced basal motion anomalies through Arctic valley and outlet glaciers with complex topographic settings and highlight the importance of dynamically incorporating basal motion into models predicting the response of the Arctic's land ice to climate change. |
format |
Article in Journal/Newspaper |
author |
Bingham, Robert G. Hubbard, Alun L. Nienow, Peter W. Sharp, Martin J. |
author_facet |
Bingham, Robert G. Hubbard, Alun L. Nienow, Peter W. Sharp, Martin J. |
author_sort |
Bingham, Robert G. |
title |
An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. |
title_short |
An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. |
title_full |
An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. |
title_fullStr |
An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. |
title_full_unstemmed |
An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. |
title_sort |
investigation into the mechanisms controlling seasonal speedup events at a high arctic glacier. |
publisher |
American Geophysical Union |
publishDate |
2008 |
url |
http://nora.nerc.ac.uk/id/eprint/3726/ https://nora.nerc.ac.uk/id/eprint/3726/1/2007JF000832_bingham.pdf http://www.agu.org/pubs/crossref/2008/2007JF000832.shtml https://doi.org/10.1029/2007JF000832 |
long_lat |
ENVELOPE(-74.079,-74.079,79.646,79.646) |
geographic |
Arctic Ellesmere Island Canada Greenland John Evans Glacier |
geographic_facet |
Arctic Ellesmere Island Canada Greenland John Evans Glacier |
genre |
Arctic Arctic Climate change Ellesmere Island glacier glacier* Greenland Ice Sheet |
genre_facet |
Arctic Arctic Climate change Ellesmere Island glacier glacier* Greenland Ice Sheet |
op_relation |
https://nora.nerc.ac.uk/id/eprint/3726/1/2007JF000832_bingham.pdf Bingham, Robert G.; Hubbard, Alun L.; Nienow, Peter W.; Sharp, Martin J. 2008 An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier. Journal of Geophysical Research, 113 (F2), F02006. 13, pp. https://doi.org/10.1029/2007JF000832 <https://doi.org/10.1029/2007JF000832> |
op_doi |
https://doi.org/10.1029/2007JF000832 |
container_title |
Journal of Geophysical Research |
container_volume |
113 |
container_issue |
F2 |
_version_ |
1766298279427964928 |