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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ftsouthampton:oai:eprints.soton.ac.uk:469725 2023-07-30T03:58:21+02:00 Seasonality of warm water intrusions onto the continental shelf near the Totten glacier Silvano, Alessandro Rintoul, Stephen R. Kusahara, Kazuya Peña‐Molino, Beatriz Wijk, Esmee Gwyther, David E. Williams, Guy D. 2019-06-03 https://eprints.soton.ac.uk/469725/ English eng Silvano, Alessandro, Rintoul, Stephen R., Kusahara, Kazuya, Peña‐Molino, Beatriz, Wijk, Esmee, Gwyther, David E. and Williams, Guy D. (2019) Seasonality of warm water intrusions onto the continental shelf near the Totten glacier. Journal of Geophysical Research: Oceans, 124 (6), 4272-4289. (doi:10.1029/2018JC014634 <http://dx.doi.org/10.1029/2018JC014634>). Article PeerReviewed 2019 ftsouthampton https://doi.org/10.1029/2018JC014634 2023-07-09T22:55:06Z 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 ~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 Southampton: e-Prints Soton 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 Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
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 ~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, Alessandro Rintoul, Stephen R. Kusahara, Kazuya Peña‐Molino, Beatriz Wijk, Esmee Gwyther, David E. Williams, Guy D. |
spellingShingle |
Silvano, Alessandro Rintoul, Stephen R. Kusahara, Kazuya Peña‐Molino, Beatriz Wijk, Esmee Gwyther, David E. Williams, Guy D. Seasonality of warm water intrusions onto the continental shelf near the Totten glacier |
author_facet |
Silvano, Alessandro Rintoul, Stephen R. Kusahara, Kazuya Peña‐Molino, Beatriz Wijk, Esmee Gwyther, David E. Williams, Guy D. |
author_sort |
Silvano, Alessandro |
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 |
publishDate |
2019 |
url |
https://eprints.soton.ac.uk/469725/ |
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 |
Silvano, Alessandro, Rintoul, Stephen R., Kusahara, Kazuya, Peña‐Molino, Beatriz, Wijk, Esmee, Gwyther, David E. and Williams, Guy D. (2019) Seasonality of warm water intrusions onto the continental shelf near the Totten glacier. Journal of Geophysical Research: Oceans, 124 (6), 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_ |
1772821180215984128 |