Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms
Basal melting of ice shelves is inherently difficult to quantify through direct observations, yet it is a critical factor controlling Antarctic mass balance and global sea‐level rise. While much research attention is paid to larger ice shelves and those experiencing the most rapid change, many small...
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Online Access: | https://doi.org/10.1029/2019JC015882 http://ecite.utas.edu.au/139536 |
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ftunivtasecite:oai:ecite.utas.edu.au:139536 2023-05-15T13:42:40+02:00 Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms Gwyther, DE Spain, EA King, P Guihen, D Williams, GD Evans, E Cook, S Richter, O Galton-Fenzi, BK Coleman, R 2020 application/pdf https://doi.org/10.1029/2019JC015882 http://ecite.utas.edu.au/139536 en eng Wiley-Blackwell Publishing Inc. http://ecite.utas.edu.au/139536/1/139536 - Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf.pdf http://dx.doi.org/10.1029/2019JC015882 Gwyther, DE and Spain, EA and King, P and Guihen, D and Williams, GD and Evans, E and Cook, S and Richter, O and Galton-Fenzi, BK and Coleman, R, Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms, JGR Oceans, 125, (6) Article e2019JC015882. ISSN 2169-9275 (2020) [Refereed Article] http://ecite.utas.edu.au/139536 Earth Sciences Oceanography Physical oceanography Refereed Article PeerReviewed 2020 ftunivtasecite https://doi.org/10.1029/2019JC015882 2022-08-29T22:17:57Z Basal melting of ice shelves is inherently difficult to quantify through direct observations, yet it is a critical factor controlling Antarctic mass balance and global sea‐level rise. While much research attention is paid to larger ice shelves and those experiencing the most rapid change, many smaller, unstudied ice shelves offer valuable insights. Here, we investigate the oceanographic conditions and melting beneath the Srsdal ice shelf, East Antarctica. We present results from the 2018/2019 Srsdal deployment of the University of Tasmania's autonomous underwater vehicle nupiri muka . Oceanography adjacent to and beneath the ice shelf front shows a cold and relatively saline environment dominated by Winter Water and Dense Shelf Water, while bathymetry measurements show a deep (∼1,200m) trough running into the ice shelf cavity. Two multiyear deployments of Autonomous Phase‐sensitive Radar Echo Sounders on the surface of the ice shelf show weak melt rates (average of 1.6 and 2.3myr −1 ) with low temporal variability. These observations are supported by numerical ocean model and satellite estimates of melting. We speculate that the presence of a ∼825m thick (350m to at least 1,175m) homogeneous layer of cold, dense water blocks access from warmer waters that intrude into Prydz Bay from offshore, resulting in weak melt rates. However, the newly identified trough means that the ice shelf is vulnerable to any decrease in polynya activity that allows warm water to enter the cavity. This could lead to increased basal melting and mass loss through this sector of Antarctica. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Shelf Ice Shelves Prydz Bay eCite UTAS (University of Tasmania) Antarctic East Antarctica Prydz Bay Journal of Geophysical Research: Oceans 125 6 |
institution |
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 Gwyther, DE Spain, EA King, P Guihen, D Williams, GD Evans, E Cook, S Richter, O Galton-Fenzi, BK Coleman, R Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms |
topic_facet |
Earth Sciences Oceanography Physical oceanography |
description |
Basal melting of ice shelves is inherently difficult to quantify through direct observations, yet it is a critical factor controlling Antarctic mass balance and global sea‐level rise. While much research attention is paid to larger ice shelves and those experiencing the most rapid change, many smaller, unstudied ice shelves offer valuable insights. Here, we investigate the oceanographic conditions and melting beneath the Srsdal ice shelf, East Antarctica. We present results from the 2018/2019 Srsdal deployment of the University of Tasmania's autonomous underwater vehicle nupiri muka . Oceanography adjacent to and beneath the ice shelf front shows a cold and relatively saline environment dominated by Winter Water and Dense Shelf Water, while bathymetry measurements show a deep (∼1,200m) trough running into the ice shelf cavity. Two multiyear deployments of Autonomous Phase‐sensitive Radar Echo Sounders on the surface of the ice shelf show weak melt rates (average of 1.6 and 2.3myr −1 ) with low temporal variability. These observations are supported by numerical ocean model and satellite estimates of melting. We speculate that the presence of a ∼825m thick (350m to at least 1,175m) homogeneous layer of cold, dense water blocks access from warmer waters that intrude into Prydz Bay from offshore, resulting in weak melt rates. However, the newly identified trough means that the ice shelf is vulnerable to any decrease in polynya activity that allows warm water to enter the cavity. This could lead to increased basal melting and mass loss through this sector of Antarctica. |
format |
Article in Journal/Newspaper |
author |
Gwyther, DE Spain, EA King, P Guihen, D Williams, GD Evans, E Cook, S Richter, O Galton-Fenzi, BK Coleman, R |
author_facet |
Gwyther, DE Spain, EA King, P Guihen, D Williams, GD Evans, E Cook, S Richter, O Galton-Fenzi, BK Coleman, R |
author_sort |
Gwyther, DE |
title |
Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms |
title_short |
Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms |
title_full |
Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms |
title_fullStr |
Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms |
title_full_unstemmed |
Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms |
title_sort |
cold ocean cavity and weak basal melting of the sorsdal ice shelf revealed by surveys using autonomous platforms |
publisher |
Wiley-Blackwell Publishing Inc. |
publishDate |
2020 |
url |
https://doi.org/10.1029/2019JC015882 http://ecite.utas.edu.au/139536 |
geographic |
Antarctic East Antarctica Prydz Bay |
geographic_facet |
Antarctic East Antarctica Prydz Bay |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Shelf Ice Shelves Prydz Bay |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Shelf Ice Shelves Prydz Bay |
op_relation |
http://ecite.utas.edu.au/139536/1/139536 - Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf.pdf http://dx.doi.org/10.1029/2019JC015882 Gwyther, DE and Spain, EA and King, P and Guihen, D and Williams, GD and Evans, E and Cook, S and Richter, O and Galton-Fenzi, BK and Coleman, R, Cold ocean cavity and weak basal melting of the Sorsdal Ice Shelf revealed by surveys using autonomous platforms, JGR Oceans, 125, (6) Article e2019JC015882. ISSN 2169-9275 (2020) [Refereed Article] http://ecite.utas.edu.au/139536 |
op_doi |
https://doi.org/10.1029/2019JC015882 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
125 |
container_issue |
6 |
_version_ |
1766171142210453504 |