Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier
Warm Modified Circumpolar Deep Water (MCDW) from the Southern Ocean drives rapid basal melt of the Totten Ice Shelf on the Sabrina Coast (East Antarctica), affecting the mass balance of the grounded Totten Glacier. Recent observations show that MCDW intrudes onto the continental shelf through a depr...
Published in: | Journal of Geophysical Research: Oceans |
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Language: | English |
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Wiley-Blackwell Publishing Inc.
2019
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Online Access: | https://eprints.utas.edu.au/30939/ https://eprints.utas.edu.au/30939/1/133777%20-%20Seasonality%20of%20Warm%20Water%20Intrusions%20Onto%20theContinental%20Shelf.pdf |
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ftunivtasmania:oai:eprints.utas.edu.au:30939 2023-05-15T13:31:53+02:00 Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier Silvano, A Rintoul, SR Kusahara, K Pena-Molino, B van Wijk, E Gwyther, DE Williams, GD 2019 application/pdf https://eprints.utas.edu.au/30939/ https://eprints.utas.edu.au/30939/1/133777%20-%20Seasonality%20of%20Warm%20Water%20Intrusions%20Onto%20theContinental%20Shelf.pdf en eng Wiley-Blackwell Publishing Inc. https://eprints.utas.edu.au/30939/1/133777%20-%20Seasonality%20of%20Warm%20Water%20Intrusions%20Onto%20theContinental%20Shelf.pdf Silvano, A, Rintoul, SR orcid:0000-0002-7055-9876 , Kusahara, K orcid:0000-0003-4067-7959 , Pena-Molino, B orcid:0000-0003-1587-1696 , van Wijk, E, Gwyther, DE orcid:0000-0002-7218-2785 and Williams, GD orcid:0000-0003-1769-8356 2019 , 'Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier' , Journal of Geophysical Research: Oceans, vol. 124, no. 6 , pp. 4272-4289 , doi:10.1029/2018JC014634 <http://dx.doi.org/10.1029/2018JC014634>. Antarctica oceanography Totten Moscow University East Antarctica Circumpolar Deep Water basal melting sea level rise Article PeerReviewed 2019 ftunivtasmania https://doi.org/10.1029/2018JC014634 2021-09-13T22:20:09Z Warm Modified Circumpolar Deep Water (MCDW) from the Southern Ocean drives rapid basal melt of the Totten Ice Shelf on the Sabrina Coast (East Antarctica), affecting the mass balance of the grounded Totten Glacier. Recent observations show that MCDW intrudes onto the continental shelf through a depression at the shelf break. Here we investigate such intrusions by combining (1) new oceanographic and bathymetric observations collected for two consecutive years by profiling floats in the depression south of the shelf break, (2) oceanographic measurements collected by conductivity‐temperature‐depth‐instrumented seals on continental slope, and (3) an ocean model. The depression provides a pathway for persistent inflow of warm (0‐1°C) MCDW to the inner shelf. In austral autumn and early winter MCDW intrusions were up to 0.5°C warmer and were are ~75 m thicker than in spring and summer. The seasonality of the flow on the continental slope explains the seasonality of the intrusions. The MCDW layer on the continental slope is warmer and thicker to the east of the depression than to the west. In autumn and early winter a strong, top‐to‐bottom westward current (Antarctic Slope Current) transports the warmer and thicker MCDW layer along the slope and is diverted poleward at the eastern entrance of the depression. A bottom‐intensified eastward current (Antarctic Slope Undercurrent) develops in other months, allowing cooler and thinner intrusions to enter the depression from the west. Our study illustrates how circulation on the Antarctic slope regulates the ocean heat delivery to the continental shelf and ultimately to the ice shelves. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Shelf Ice Shelves Southern Ocean Totten Glacier Totten Ice Shelf University of Tasmania: UTas ePrints Antarctic Southern Ocean The Antarctic East Antarctica Austral Totten Glacier ENVELOPE(116.333,116.333,-66.833,-66.833) Sabrina Coast ENVELOPE(118.550,118.550,-67.000,-67.000) Eastern Entrance ENVELOPE(-132.987,-132.987,69.458,69.458) Journal of Geophysical Research: Oceans 124 6 4272 4289 |
institution |
Open Polar |
collection |
University of Tasmania: UTas ePrints |
op_collection_id |
ftunivtasmania |
language |
English |
topic |
Antarctica oceanography Totten Moscow University East Antarctica Circumpolar Deep Water basal melting sea level rise |
spellingShingle |
Antarctica oceanography Totten Moscow University East Antarctica Circumpolar Deep Water basal melting sea level rise Silvano, A Rintoul, SR Kusahara, K Pena-Molino, B van Wijk, E Gwyther, DE Williams, GD Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier |
topic_facet |
Antarctica oceanography Totten Moscow University East Antarctica Circumpolar Deep Water basal melting sea level rise |
description |
Warm Modified Circumpolar Deep Water (MCDW) from the Southern Ocean drives rapid basal melt of the Totten Ice Shelf on the Sabrina Coast (East Antarctica), affecting the mass balance of the grounded Totten Glacier. Recent observations show that MCDW intrudes onto the continental shelf through a depression at the shelf break. Here we investigate such intrusions by combining (1) new oceanographic and bathymetric observations collected for two consecutive years by profiling floats in the depression south of the shelf break, (2) oceanographic measurements collected by conductivity‐temperature‐depth‐instrumented seals on continental slope, and (3) an ocean model. The depression provides a pathway for persistent inflow of warm (0‐1°C) MCDW to the inner shelf. In austral autumn and early winter MCDW intrusions were up to 0.5°C warmer and were are ~75 m thicker than in spring and summer. The seasonality of the flow on the continental slope explains the seasonality of the intrusions. The MCDW layer on the continental slope is warmer and thicker to the east of the depression than to the west. In autumn and early winter a strong, top‐to‐bottom westward current (Antarctic Slope Current) transports the warmer and thicker MCDW layer along the slope and is diverted poleward at the eastern entrance of the depression. A bottom‐intensified eastward current (Antarctic Slope Undercurrent) develops in other months, allowing cooler and thinner intrusions to enter the depression from the west. Our study illustrates how circulation on the Antarctic slope regulates the ocean heat delivery to the continental shelf and ultimately to the ice shelves. |
format |
Article in Journal/Newspaper |
author |
Silvano, A Rintoul, SR Kusahara, K Pena-Molino, B van Wijk, E Gwyther, DE Williams, GD |
author_facet |
Silvano, A Rintoul, SR Kusahara, K Pena-Molino, B van Wijk, E Gwyther, DE Williams, GD |
author_sort |
Silvano, A |
title |
Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier |
title_short |
Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier |
title_full |
Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier |
title_fullStr |
Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier |
title_full_unstemmed |
Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier |
title_sort |
seasonality of warm water intrusions onto the continental shelf near the totten glacier |
publisher |
Wiley-Blackwell Publishing Inc. |
publishDate |
2019 |
url |
https://eprints.utas.edu.au/30939/ https://eprints.utas.edu.au/30939/1/133777%20-%20Seasonality%20of%20Warm%20Water%20Intrusions%20Onto%20theContinental%20Shelf.pdf |
long_lat |
ENVELOPE(116.333,116.333,-66.833,-66.833) ENVELOPE(118.550,118.550,-67.000,-67.000) ENVELOPE(-132.987,-132.987,69.458,69.458) |
geographic |
Antarctic Southern Ocean The Antarctic East Antarctica Austral Totten Glacier Sabrina Coast Eastern Entrance |
geographic_facet |
Antarctic Southern Ocean The Antarctic East Antarctica Austral Totten Glacier Sabrina Coast Eastern Entrance |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Shelf Ice Shelves Southern Ocean Totten Glacier Totten Ice Shelf |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Shelf Ice Shelves Southern Ocean Totten Glacier Totten Ice Shelf |
op_relation |
https://eprints.utas.edu.au/30939/1/133777%20-%20Seasonality%20of%20Warm%20Water%20Intrusions%20Onto%20theContinental%20Shelf.pdf Silvano, A, Rintoul, SR orcid:0000-0002-7055-9876 , Kusahara, K orcid:0000-0003-4067-7959 , Pena-Molino, B orcid:0000-0003-1587-1696 , van Wijk, E, Gwyther, DE orcid:0000-0002-7218-2785 and Williams, GD orcid:0000-0003-1769-8356 2019 , 'Seasonality of warm water intrusions onto the continental shelf near the Totten Glacier' , Journal of Geophysical Research: Oceans, vol. 124, no. 6 , pp. 4272-4289 , doi:10.1029/2018JC014634 <http://dx.doi.org/10.1029/2018JC014634>. |
op_doi |
https://doi.org/10.1029/2018JC014634 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
124 |
container_issue |
6 |
container_start_page |
4272 |
op_container_end_page |
4289 |
_version_ |
1766021941275131904 |