Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event
Cook Glacier drains a large proportion of the Wilkes Subglacial Basin in East Antarctica, a region thought to be vulnerable to marine ice sheet instability and with potential to make a significant contribution to sea level. Despite its importance, there have been very few observations of its longer-...
Published in: | The Cryosphere |
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Copernicus Publications
2018
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Online Access: | https://doi.org/10.5194/tc-12-3123-2018 https://www.the-cryosphere.net/12/3123/2018/tc-12-3123-2018.pdf https://doaj.org/article/b5585a2394e14b04a30af48c76817f55 |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:b5585a2394e14b04a30af48c76817f55 2023-05-15T13:52:49+02:00 Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event B. W. J. Miles C. R. Stokes S. S. R. Jamieson 2018-10-01 https://doi.org/10.5194/tc-12-3123-2018 https://www.the-cryosphere.net/12/3123/2018/tc-12-3123-2018.pdf https://doaj.org/article/b5585a2394e14b04a30af48c76817f55 en eng Copernicus Publications doi:10.5194/tc-12-3123-2018 1994-0416 1994-0424 https://www.the-cryosphere.net/12/3123/2018/tc-12-3123-2018.pdf https://doaj.org/article/b5585a2394e14b04a30af48c76817f55 undefined The Cryosphere, Vol 12, Pp 3123-3136 (2018) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2018 fttriple https://doi.org/10.5194/tc-12-3123-2018 2023-01-22T18:11:33Z Cook Glacier drains a large proportion of the Wilkes Subglacial Basin in East Antarctica, a region thought to be vulnerable to marine ice sheet instability and with potential to make a significant contribution to sea level. Despite its importance, there have been very few observations of its longer-term behaviour (e.g. of velocity or changes at its ice front). Here we use a variety of satellite imagery to produce a time series of ice front position change from 1947 to 2017 and ice velocity from 1973 to 2017. Cook Glacier has two distinct outlets (termed East and West), and we observe the near-complete loss of the Cook West Ice Shelf at some time between 1973 and 1989. This was associated with a doubling of the velocity of Cook West Glacier, which may also be linked to previously published reports of inland thinning. The loss of the Cook West Ice Shelf is surprising given that the present-day ocean climate conditions in the region are not typically associated with catastrophic ice shelf loss. However, we speculate that a more intense ocean climate forcing in the mid-20th century may have been important in forcing its collapse. Since the loss of the Cook West Ice Shelf, the presence of landfast sea ice and mélange in the newly formed embayment appears to be important in stabilizing the glacier front and enabling periodic advances. We also show that the last calving event at the larger Cook East Ice Shelf resulted in the retreat of its ice front into a dynamically important portion of the ice shelf and observe a short-lived increase in velocity of Cook East between 2006 and 2007, which we link to the drainage of subglacial Lake Cook. Taken together, these observations suggest that the velocity, and hence discharge, of Cook Glacier is highly sensitive to changes at its terminus, but a more detailed process-based analysis of this potentially vulnerable region requires further oceanic and bathymetric data. Article in Journal/Newspaper Antarc* Antarctica Cook Glacier East Antarctica Ice Sheet Ice Shelf Sea ice The Cryosphere West Ice Shelf Unknown Cook Glacier ENVELOPE(-36.191,-36.191,-54.446,-54.446) East Antarctica West Ice Shelf ENVELOPE(85.000,85.000,-67.000,-67.000) Wilkes Subglacial Basin ENVELOPE(145.000,145.000,-75.000,-75.000) The Cryosphere 12 10 3123 3136 |
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English |
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geo envir |
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geo envir B. W. J. Miles C. R. Stokes S. S. R. Jamieson Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event |
topic_facet |
geo envir |
description |
Cook Glacier drains a large proportion of the Wilkes Subglacial Basin in East Antarctica, a region thought to be vulnerable to marine ice sheet instability and with potential to make a significant contribution to sea level. Despite its importance, there have been very few observations of its longer-term behaviour (e.g. of velocity or changes at its ice front). Here we use a variety of satellite imagery to produce a time series of ice front position change from 1947 to 2017 and ice velocity from 1973 to 2017. Cook Glacier has two distinct outlets (termed East and West), and we observe the near-complete loss of the Cook West Ice Shelf at some time between 1973 and 1989. This was associated with a doubling of the velocity of Cook West Glacier, which may also be linked to previously published reports of inland thinning. The loss of the Cook West Ice Shelf is surprising given that the present-day ocean climate conditions in the region are not typically associated with catastrophic ice shelf loss. However, we speculate that a more intense ocean climate forcing in the mid-20th century may have been important in forcing its collapse. Since the loss of the Cook West Ice Shelf, the presence of landfast sea ice and mélange in the newly formed embayment appears to be important in stabilizing the glacier front and enabling periodic advances. We also show that the last calving event at the larger Cook East Ice Shelf resulted in the retreat of its ice front into a dynamically important portion of the ice shelf and observe a short-lived increase in velocity of Cook East between 2006 and 2007, which we link to the drainage of subglacial Lake Cook. Taken together, these observations suggest that the velocity, and hence discharge, of Cook Glacier is highly sensitive to changes at its terminus, but a more detailed process-based analysis of this potentially vulnerable region requires further oceanic and bathymetric data. |
format |
Article in Journal/Newspaper |
author |
B. W. J. Miles C. R. Stokes S. S. R. Jamieson |
author_facet |
B. W. J. Miles C. R. Stokes S. S. R. Jamieson |
author_sort |
B. W. J. Miles |
title |
Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event |
title_short |
Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event |
title_full |
Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event |
title_fullStr |
Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event |
title_full_unstemmed |
Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event |
title_sort |
velocity increases at cook glacier, east antarctica, linked to ice shelf loss and a subglacial flood event |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-3123-2018 https://www.the-cryosphere.net/12/3123/2018/tc-12-3123-2018.pdf https://doaj.org/article/b5585a2394e14b04a30af48c76817f55 |
long_lat |
ENVELOPE(-36.191,-36.191,-54.446,-54.446) ENVELOPE(85.000,85.000,-67.000,-67.000) ENVELOPE(145.000,145.000,-75.000,-75.000) |
geographic |
Cook Glacier East Antarctica West Ice Shelf Wilkes Subglacial Basin |
geographic_facet |
Cook Glacier East Antarctica West Ice Shelf Wilkes Subglacial Basin |
genre |
Antarc* Antarctica Cook Glacier East Antarctica Ice Sheet Ice Shelf Sea ice The Cryosphere West Ice Shelf |
genre_facet |
Antarc* Antarctica Cook Glacier East Antarctica Ice Sheet Ice Shelf Sea ice The Cryosphere West Ice Shelf |
op_source |
The Cryosphere, Vol 12, Pp 3123-3136 (2018) |
op_relation |
doi:10.5194/tc-12-3123-2018 1994-0416 1994-0424 https://www.the-cryosphere.net/12/3123/2018/tc-12-3123-2018.pdf https://doaj.org/article/b5585a2394e14b04a30af48c76817f55 |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-12-3123-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
10 |
container_start_page |
3123 |
op_container_end_page |
3136 |
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1766257583746711552 |