Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up
The floating ice shelves and glacier tongues which fringe the Antarctic continent are important because they help buttress ice flow from the ice sheet interior. Dynamic feedbacks associated with glacier calving have the potential to reduce buttressing and subsequently increase ice flow into the ocea...
Published in: | The Cryosphere |
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Language: | English |
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Copernicus Publications
2017
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Online Access: | https://doi.org/10.5194/tc-11-427-2017 http://www.the-cryosphere.net/11/427/2017/tc-11-427-2017.pdf https://doaj.org/article/f4e74b87ce794560927864e063cd77e2 |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:f4e74b87ce794560927864e063cd77e2 2023-05-15T14:00:08+02:00 Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up B. W. J. Miles C. R. Stokes S. S. R. Jamieson 2017-02-01 https://doi.org/10.5194/tc-11-427-2017 http://www.the-cryosphere.net/11/427/2017/tc-11-427-2017.pdf https://doaj.org/article/f4e74b87ce794560927864e063cd77e2 en eng Copernicus Publications 1994-0416 1994-0424 doi:10.5194/tc-11-427-2017 http://www.the-cryosphere.net/11/427/2017/tc-11-427-2017.pdf https://doaj.org/article/f4e74b87ce794560927864e063cd77e2 undefined The Cryosphere, Vol 11, Iss 1, Pp 427-442 (2017) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2017 fttriple https://doi.org/10.5194/tc-11-427-2017 2023-01-22T19:35:19Z The floating ice shelves and glacier tongues which fringe the Antarctic continent are important because they help buttress ice flow from the ice sheet interior. Dynamic feedbacks associated with glacier calving have the potential to reduce buttressing and subsequently increase ice flow into the ocean. However, there are few high temporal resolution studies on glacier calving, especially in East Antarctica. Here we use ENVISAT ASAR wide swath mode imagery to investigate monthly glacier terminus change across six marine-terminating outlet glaciers in Porpoise Bay (76° S, 128° E), Wilkes Land (East Antarctica), between November 2002 and March 2012. This reveals a large near-simultaneous calving event in January 2007, resulting in a total of ∼ 2900 km2 of ice being removed from glacier tongues. We also observe the start of a similar large near-simultaneous calving event in March 2016. Our observations suggest that both of these large calving events are driven by the break-up of the multi-year sea ice which usually occupies Porpoise Bay. However, these break-up events appear to have been driven by contrasting mechanisms. We link the 2007 sea ice break-up to atmospheric circulation anomalies in December 2005 weakening the multi-year sea ice through a combination of surface melt and a change in wind direction prior to its eventual break-up in January 2007. In contrast, the 2016 break-up event is linked to the terminus of Holmes (West) Glacier pushing the multi-year sea ice further into the open ocean, making the sea ice more vulnerable to break-up. In the context of predicted future warming and the sensitivity of sea ice to changes in climate, our results highlight the importance of interactions between landfast sea ice and glacier tongue stability in East Antarctica. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelves Sea ice The Cryosphere Wilkes Land Unknown Antarctic Asar ENVELOPE(134.033,134.033,68.667,68.667) Buttress ENVELOPE(-57.083,-57.083,-63.550,-63.550) East Antarctica Porpoise Bay ENVELOPE(128.667,128.667,-66.750,-66.750) The Antarctic Wilkes Land ENVELOPE(120.000,120.000,-69.000,-69.000) The Cryosphere 11 1 427 442 |
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Open Polar |
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English |
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spellingShingle |
geo envir B. W. J. Miles C. R. Stokes S. S. R. Jamieson Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up |
topic_facet |
geo envir |
description |
The floating ice shelves and glacier tongues which fringe the Antarctic continent are important because they help buttress ice flow from the ice sheet interior. Dynamic feedbacks associated with glacier calving have the potential to reduce buttressing and subsequently increase ice flow into the ocean. However, there are few high temporal resolution studies on glacier calving, especially in East Antarctica. Here we use ENVISAT ASAR wide swath mode imagery to investigate monthly glacier terminus change across six marine-terminating outlet glaciers in Porpoise Bay (76° S, 128° E), Wilkes Land (East Antarctica), between November 2002 and March 2012. This reveals a large near-simultaneous calving event in January 2007, resulting in a total of ∼ 2900 km2 of ice being removed from glacier tongues. We also observe the start of a similar large near-simultaneous calving event in March 2016. Our observations suggest that both of these large calving events are driven by the break-up of the multi-year sea ice which usually occupies Porpoise Bay. However, these break-up events appear to have been driven by contrasting mechanisms. We link the 2007 sea ice break-up to atmospheric circulation anomalies in December 2005 weakening the multi-year sea ice through a combination of surface melt and a change in wind direction prior to its eventual break-up in January 2007. In contrast, the 2016 break-up event is linked to the terminus of Holmes (West) Glacier pushing the multi-year sea ice further into the open ocean, making the sea ice more vulnerable to break-up. In the context of predicted future warming and the sensitivity of sea ice to changes in climate, our results highlight the importance of interactions between landfast sea ice and glacier tongue stability in East Antarctica. |
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 |
Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up |
title_short |
Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up |
title_full |
Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up |
title_fullStr |
Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up |
title_full_unstemmed |
Simultaneous disintegration of outlet glaciers in Porpoise Bay (Wilkes Land), East Antarctica, driven by sea ice break-up |
title_sort |
simultaneous disintegration of outlet glaciers in porpoise bay (wilkes land), east antarctica, driven by sea ice break-up |
publisher |
Copernicus Publications |
publishDate |
2017 |
url |
https://doi.org/10.5194/tc-11-427-2017 http://www.the-cryosphere.net/11/427/2017/tc-11-427-2017.pdf https://doaj.org/article/f4e74b87ce794560927864e063cd77e2 |
long_lat |
ENVELOPE(134.033,134.033,68.667,68.667) ENVELOPE(-57.083,-57.083,-63.550,-63.550) ENVELOPE(128.667,128.667,-66.750,-66.750) ENVELOPE(120.000,120.000,-69.000,-69.000) |
geographic |
Antarctic Asar Buttress East Antarctica Porpoise Bay The Antarctic Wilkes Land |
geographic_facet |
Antarctic Asar Buttress East Antarctica Porpoise Bay The Antarctic Wilkes Land |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelves Sea ice The Cryosphere Wilkes Land |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelves Sea ice The Cryosphere Wilkes Land |
op_source |
The Cryosphere, Vol 11, Iss 1, Pp 427-442 (2017) |
op_relation |
1994-0416 1994-0424 doi:10.5194/tc-11-427-2017 http://www.the-cryosphere.net/11/427/2017/tc-11-427-2017.pdf https://doaj.org/article/f4e74b87ce794560927864e063cd77e2 |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-11-427-2017 |
container_title |
The Cryosphere |
container_volume |
11 |
container_issue |
1 |
container_start_page |
427 |
op_container_end_page |
442 |
_version_ |
1766269122529722368 |