Basal terraces beneath Totten Glacier, East Antarctica
The Totten Glacier is the primary outlet of the Aurora Subglacial Basin (ASB), draining at least 3.5 m of eustatic sea-level potential into the Sabrina Coast alongside the Moscow University Ice Shelf. Recent work has shown that the ASB has drained and filled many times since large-scale glaciation b...
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ftunivtasecite:oai:ecite.utas.edu.au:116900 2023-05-15T13:49:03+02:00 Basal terraces beneath Totten Glacier, East Antarctica Greenbaum, J Blankenship, D Schroeder, D Gwyther, D Young, D Lindzey, L Roberts, J Warner, RC van Ommen, TD 2016 application/pdf http://ecite.utas.edu.au/116900 en eng . http://ecite.utas.edu.au/116900/1/IGS_Greenbaum_abstract.pdf Greenbaum, J and Blankenship, D and Schroeder, D and Gwyther, D and Young, D and Lindzey, L and Roberts, J and Warner, RC and van Ommen, TD, Basal terraces beneath Totten Glacier, East Antarctica, International Glaciological Society: International Symposium on Interactions of Ice Sheets and Glaciers with the Ocean Abstracts, 10-15 July 2016, La Jolla, California, pp. 74A2127. (2016) [Conference Extract] http://ecite.utas.edu.au/116900 Earth Sciences Oceanography Physical Oceanography Conference Extract NonPeerReviewed 2016 ftunivtasecite 2019-12-13T22:16:24Z The Totten Glacier is the primary outlet of the Aurora Subglacial Basin (ASB), draining at least 3.5 m of eustatic sea-level potential into the Sabrina Coast alongside the Moscow University Ice Shelf. Recent work has shown that the ASB has drained and filled many times since large-scale glaciation began, including evidence that it collapsed during the Pliocene. Steady thinning rates near the grounding line of Totten Glacier are the largest in East Antarctica and the nature of the thinning suggests that it is driven by enhanced basal melting due to ocean processes. Warm modified circumpolar deep water (MCDW), which has been linked to glacier retreat in West Antarctica, has been observed in summer and winter on the Sabrina Coast continental shelf by multiple marine expeditions and recent work has shown that depressions in the seafloor likely make the ice shelf vulnerable to MCDW intrusions that could cause enhanced basal melting. Here we use post-processed, focused airborne radar observations of the Totten Glacier Ice Shelf to delineate multi-kilometer-wide basal channels and flat basal terraces that are associated with high basal reflectivity and specularity anomalies and correspondingly large ice surface depressions that indicate active basal melt processes. Sub-ice-shelf ocean circulation modeling and under ice robotic observations of Pine Island Glacier Ice Shelf in West Antarctica and the Petermann Glacier Ice Shelf in Greenland have shown that basal terraces associated with large basal channels are an indication of rapidly melting ice shelves. Therefore, these new results identify an East Antarctic example of rapid basal melting processes and demonstrate that airborne radar can be used to identify basal characteristics relevant to ice-shelf basal processes. Conference Object Antarc* Antarctic Antarctica East Antarctica glacier Greenland Ice Shelf Ice Shelves Moscow University Ice Shelf Petermann glacier Pine Island Pine Island Glacier Totten Glacier West Antarctica eCite UTAS (University of Tasmania) Antarctic East Antarctica Greenland Moscow University Ice Shelf ENVELOPE(121.000,121.000,-67.000,-67.000) Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Sabrina Coast ENVELOPE(118.550,118.550,-67.000,-67.000) Totten Glacier ENVELOPE(116.333,116.333,-66.833,-66.833) West Antarctica |
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Open Polar |
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eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Oceanography Physical Oceanography |
spellingShingle |
Earth Sciences Oceanography Physical Oceanography Greenbaum, J Blankenship, D Schroeder, D Gwyther, D Young, D Lindzey, L Roberts, J Warner, RC van Ommen, TD Basal terraces beneath Totten Glacier, East Antarctica |
topic_facet |
Earth Sciences Oceanography Physical Oceanography |
description |
The Totten Glacier is the primary outlet of the Aurora Subglacial Basin (ASB), draining at least 3.5 m of eustatic sea-level potential into the Sabrina Coast alongside the Moscow University Ice Shelf. Recent work has shown that the ASB has drained and filled many times since large-scale glaciation began, including evidence that it collapsed during the Pliocene. Steady thinning rates near the grounding line of Totten Glacier are the largest in East Antarctica and the nature of the thinning suggests that it is driven by enhanced basal melting due to ocean processes. Warm modified circumpolar deep water (MCDW), which has been linked to glacier retreat in West Antarctica, has been observed in summer and winter on the Sabrina Coast continental shelf by multiple marine expeditions and recent work has shown that depressions in the seafloor likely make the ice shelf vulnerable to MCDW intrusions that could cause enhanced basal melting. Here we use post-processed, focused airborne radar observations of the Totten Glacier Ice Shelf to delineate multi-kilometer-wide basal channels and flat basal terraces that are associated with high basal reflectivity and specularity anomalies and correspondingly large ice surface depressions that indicate active basal melt processes. Sub-ice-shelf ocean circulation modeling and under ice robotic observations of Pine Island Glacier Ice Shelf in West Antarctica and the Petermann Glacier Ice Shelf in Greenland have shown that basal terraces associated with large basal channels are an indication of rapidly melting ice shelves. Therefore, these new results identify an East Antarctic example of rapid basal melting processes and demonstrate that airborne radar can be used to identify basal characteristics relevant to ice-shelf basal processes. |
format |
Conference Object |
author |
Greenbaum, J Blankenship, D Schroeder, D Gwyther, D Young, D Lindzey, L Roberts, J Warner, RC van Ommen, TD |
author_facet |
Greenbaum, J Blankenship, D Schroeder, D Gwyther, D Young, D Lindzey, L Roberts, J Warner, RC van Ommen, TD |
author_sort |
Greenbaum, J |
title |
Basal terraces beneath Totten Glacier, East Antarctica |
title_short |
Basal terraces beneath Totten Glacier, East Antarctica |
title_full |
Basal terraces beneath Totten Glacier, East Antarctica |
title_fullStr |
Basal terraces beneath Totten Glacier, East Antarctica |
title_full_unstemmed |
Basal terraces beneath Totten Glacier, East Antarctica |
title_sort |
basal terraces beneath totten glacier, east antarctica |
publisher |
. |
publishDate |
2016 |
url |
http://ecite.utas.edu.au/116900 |
long_lat |
ENVELOPE(121.000,121.000,-67.000,-67.000) ENVELOPE(-101.000,-101.000,-75.000,-75.000) ENVELOPE(118.550,118.550,-67.000,-67.000) ENVELOPE(116.333,116.333,-66.833,-66.833) |
geographic |
Antarctic East Antarctica Greenland Moscow University Ice Shelf Pine Island Glacier Sabrina Coast Totten Glacier West Antarctica |
geographic_facet |
Antarctic East Antarctica Greenland Moscow University Ice Shelf Pine Island Glacier Sabrina Coast Totten Glacier West Antarctica |
genre |
Antarc* Antarctic Antarctica East Antarctica glacier Greenland Ice Shelf Ice Shelves Moscow University Ice Shelf Petermann glacier Pine Island Pine Island Glacier Totten Glacier West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica glacier Greenland Ice Shelf Ice Shelves Moscow University Ice Shelf Petermann glacier Pine Island Pine Island Glacier Totten Glacier West Antarctica |
op_relation |
http://ecite.utas.edu.au/116900/1/IGS_Greenbaum_abstract.pdf Greenbaum, J and Blankenship, D and Schroeder, D and Gwyther, D and Young, D and Lindzey, L and Roberts, J and Warner, RC and van Ommen, TD, Basal terraces beneath Totten Glacier, East Antarctica, International Glaciological Society: International Symposium on Interactions of Ice Sheets and Glaciers with the Ocean Abstracts, 10-15 July 2016, La Jolla, California, pp. 74A2127. (2016) [Conference Extract] http://ecite.utas.edu.au/116900 |
_version_ |
1766250704669769728 |