Circulation and melting beneath George VI Ice Shelf, Antarctica
Introduction George VI Ice Shelf, sandwiched between the western coast of Palmer Land and the eastern coast of Alexander Island, is the largest and most studied of the west Antarctic Peninsula ice shelves. It covers an area of approximately 25,000 km2 and is underlain by Circumpolar Deep Water (CDW)...
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ftnerc:oai:nora.nerc.ac.uk:15748 2023-05-15T13:15:21+02:00 Circulation and melting beneath George VI Ice Shelf, Antarctica Jenkins, Adrian Jacobs, Stan 2007 http://nora.nerc.ac.uk/id/eprint/15748/ http://folk.uib.no/ngfso/FRISP/Rep17/jenkins06.pdf unknown University of Bergen Jenkins, Adrian orcid:0000-0002-9117-0616 Jacobs, Stan. 2007 Circulation and melting beneath George VI Ice Shelf, Antarctica. Forum for Research into Ice Shelf Processes (FRISP). Report, 17. 55-66. Glaciology Publication - Article NonPeerReviewed 2007 ftnerc 2023-02-04T19:30:05Z Introduction George VI Ice Shelf, sandwiched between the western coast of Palmer Land and the eastern coast of Alexander Island, is the largest and most studied of the west Antarctic Peninsula ice shelves. It covers an area of approximately 25,000 km2 and is underlain by Circumpolar Deep Water (CDW), with temperatures in excess of 1ºC, giving rise to rapid basal melting (Bishop and Walton, 1981; Lennon et al., 1982). The maximum ice thickness of about 500 m occurs about 70 km from the southern ice front, where a ridge of thick ice extends across George VI Sound (near 70ºW, see Figure 1) effectively dividing the upper water column into northern and southern regions. The northern ice front, which faces Marguerite Bay, appears to be near the geographical limit of ice shelf viability and has undergone a gradual retreat in recent decades (Lucchitta and Rosanova, 1998), a timeframe over which much of the nearby Wordie Ice Shelf disintegrated (Doake and Vaughan, 1991). There is extensive surface melting over the northern parts of the ice shelf and much of the ice column near the northern ice front appears to be temperate (Paren and Cooper, 1986). Conditions in the south, where the ice front faces into Ronne Entrance, are colder and the ice front position appears to be steady. The vast majority of the flow into the ice shelf comes from Palmer Land, but basal melting is sufficient to remove most of this, so that the ice is derived almost exclusively from local accumulation by the time it reaches the ice fronts (Potter et al., 1984). There is some evidence at the margins of the ice shelf to suggest that it may have disappeared completely during the early Holocene before reforming (Sugden and Clapperton, 1981; Bentley et al., 2005). Article in Journal/Newspaper Alexander Island Antarc* Antarctic Antarctic Peninsula Antarctica George VI Ice Shelf Ice Shelf Ice Shelves Palmer Land Ronne Entrance Wordie Ice Shelf Natural Environment Research Council: NERC Open Research Archive Alexander Island ENVELOPE(-69.895,-69.895,-71.287,-71.287) Antarctic Antarctic Peninsula George VI Ice Shelf ENVELOPE(-67.840,-67.840,-71.692,-71.692) George VI Sound ENVELOPE(-68.000,-68.000,-71.000,-71.000) Marguerite ENVELOPE(141.378,141.378,-66.787,-66.787) Marguerite Bay ENVELOPE(-68.000,-68.000,-68.500,-68.500) Palmer Land ENVELOPE(-65.000,-65.000,-71.500,-71.500) Paren’ ENVELOPE(163.156,163.156,62.416,62.416) Ronne Entrance ENVELOPE(-74.500,-74.500,-72.583,-72.583) Wordie ENVELOPE(-67.500,-67.500,-69.167,-69.167) Wordie Ice Shelf ENVELOPE(-67.750,-67.750,-69.250,-69.250) |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Glaciology |
spellingShingle |
Glaciology Jenkins, Adrian Jacobs, Stan Circulation and melting beneath George VI Ice Shelf, Antarctica |
topic_facet |
Glaciology |
description |
Introduction George VI Ice Shelf, sandwiched between the western coast of Palmer Land and the eastern coast of Alexander Island, is the largest and most studied of the west Antarctic Peninsula ice shelves. It covers an area of approximately 25,000 km2 and is underlain by Circumpolar Deep Water (CDW), with temperatures in excess of 1ºC, giving rise to rapid basal melting (Bishop and Walton, 1981; Lennon et al., 1982). The maximum ice thickness of about 500 m occurs about 70 km from the southern ice front, where a ridge of thick ice extends across George VI Sound (near 70ºW, see Figure 1) effectively dividing the upper water column into northern and southern regions. The northern ice front, which faces Marguerite Bay, appears to be near the geographical limit of ice shelf viability and has undergone a gradual retreat in recent decades (Lucchitta and Rosanova, 1998), a timeframe over which much of the nearby Wordie Ice Shelf disintegrated (Doake and Vaughan, 1991). There is extensive surface melting over the northern parts of the ice shelf and much of the ice column near the northern ice front appears to be temperate (Paren and Cooper, 1986). Conditions in the south, where the ice front faces into Ronne Entrance, are colder and the ice front position appears to be steady. The vast majority of the flow into the ice shelf comes from Palmer Land, but basal melting is sufficient to remove most of this, so that the ice is derived almost exclusively from local accumulation by the time it reaches the ice fronts (Potter et al., 1984). There is some evidence at the margins of the ice shelf to suggest that it may have disappeared completely during the early Holocene before reforming (Sugden and Clapperton, 1981; Bentley et al., 2005). |
format |
Article in Journal/Newspaper |
author |
Jenkins, Adrian Jacobs, Stan |
author_facet |
Jenkins, Adrian Jacobs, Stan |
author_sort |
Jenkins, Adrian |
title |
Circulation and melting beneath George VI Ice Shelf, Antarctica |
title_short |
Circulation and melting beneath George VI Ice Shelf, Antarctica |
title_full |
Circulation and melting beneath George VI Ice Shelf, Antarctica |
title_fullStr |
Circulation and melting beneath George VI Ice Shelf, Antarctica |
title_full_unstemmed |
Circulation and melting beneath George VI Ice Shelf, Antarctica |
title_sort |
circulation and melting beneath george vi ice shelf, antarctica |
publisher |
University of Bergen |
publishDate |
2007 |
url |
http://nora.nerc.ac.uk/id/eprint/15748/ http://folk.uib.no/ngfso/FRISP/Rep17/jenkins06.pdf |
long_lat |
ENVELOPE(-69.895,-69.895,-71.287,-71.287) ENVELOPE(-67.840,-67.840,-71.692,-71.692) ENVELOPE(-68.000,-68.000,-71.000,-71.000) ENVELOPE(141.378,141.378,-66.787,-66.787) ENVELOPE(-68.000,-68.000,-68.500,-68.500) ENVELOPE(-65.000,-65.000,-71.500,-71.500) ENVELOPE(163.156,163.156,62.416,62.416) ENVELOPE(-74.500,-74.500,-72.583,-72.583) ENVELOPE(-67.500,-67.500,-69.167,-69.167) ENVELOPE(-67.750,-67.750,-69.250,-69.250) |
geographic |
Alexander Island Antarctic Antarctic Peninsula George VI Ice Shelf George VI Sound Marguerite Marguerite Bay Palmer Land Paren’ Ronne Entrance Wordie Wordie Ice Shelf |
geographic_facet |
Alexander Island Antarctic Antarctic Peninsula George VI Ice Shelf George VI Sound Marguerite Marguerite Bay Palmer Land Paren’ Ronne Entrance Wordie Wordie Ice Shelf |
genre |
Alexander Island Antarc* Antarctic Antarctic Peninsula Antarctica George VI Ice Shelf Ice Shelf Ice Shelves Palmer Land Ronne Entrance Wordie Ice Shelf |
genre_facet |
Alexander Island Antarc* Antarctic Antarctic Peninsula Antarctica George VI Ice Shelf Ice Shelf Ice Shelves Palmer Land Ronne Entrance Wordie Ice Shelf |
op_relation |
Jenkins, Adrian orcid:0000-0002-9117-0616 Jacobs, Stan. 2007 Circulation and melting beneath George VI Ice Shelf, Antarctica. Forum for Research into Ice Shelf Processes (FRISP). Report, 17. 55-66. |
_version_ |
1766268138899374080 |