Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea
The dense water outflow from the Antarctic continental shelf is closely associated with the strength and position of the Antarctic Slope Front. This study explores the short-term and spatial variability of the Antarctic Slope Front system and the mechanisms that regulate cross-slope exchange using h...
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American Meteorological Society
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ftcaltechauth:oai:authors.library.caltech.edu:84079 2023-05-15T14:01:44+02:00 Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea Azaneu, Marina Heywood, Karen J. Queste, Bastien Y. Thompson, Andrew F. 2017-12 application/pdf https://authors.library.caltech.edu/84079/ https://authors.library.caltech.edu/84079/1/jpo-d-17-0030.1.pdf https://resolver.caltech.edu/CaltechAUTHORS:20180104-124655892 en eng American Meteorological Society https://authors.library.caltech.edu/84079/1/jpo-d-17-0030.1.pdf Azaneu, Marina and Heywood, Karen J. and Queste, Bastien Y. and Thompson, Andrew F. (2017) Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea. Journal of Physical Oceanography, 47 (12). pp. 2977-2997. ISSN 0022-3670. doi:10.1175/JPO-D-17-0030.1. https://resolver.caltech.edu/CaltechAUTHORS:20180104-124655892 <https://resolver.caltech.edu/CaltechAUTHORS:20180104-124655892> cc_by CC-BY Article PeerReviewed 2017 ftcaltechauth https://doi.org/10.1175/JPO-D-17-0030.1 2021-11-18T18:44:40Z The dense water outflow from the Antarctic continental shelf is closely associated with the strength and position of the Antarctic Slope Front. This study explores the short-term and spatial variability of the Antarctic Slope Front system and the mechanisms that regulate cross-slope exchange using highly temporally and spatially resolved measurements from three ocean gliders deployed in 2012. The 22 sections along the eastern Antarctic Peninsula and west of the South Orkney Islands are grouped regionally and composited by isobaths. There is consistency in the front position around the Powell Basin, varying mostly between the 500- and 800-m isobaths. In most of the study area the flow is bottom intensified. The along-slope transport of the Antarctic Slope Current (upper 1000 m) varies between 0.2 and 5.9 Sv (1 Sv ≡ 10^6 m^3 s^(−1)) and does not exhibit a regional pattern. The magnitude of the velocity field shows substantial variability, up to twice its mean value. Higher eddy kinetic energy (0.003 m^2 s^(−2)) is observed in sections with dense water, possibly because of baroclinic instabilities in the bottom layer. Distributions of potential vorticity show an increase toward the shelf along isopycnals and also in the dense water layer. Glider sections located west of the South Orkney Islands indicate a northward direction of the flow associated with the Weddell Front, which differs from previous estimates of the mean circulation. This study provides some of the first observational confirmation of the high-frequency variability associated with an active eddy field that has been suggested by recent numerical simulations in this region. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula South Orkney Islands Weddell Sea Caltech Authors (California Institute of Technology) Antarctic Antarctic Peninsula Powell Basin ENVELOPE(-49.500,-49.500,-62.250,-62.250) South Orkney Islands ENVELOPE(-45.500,-45.500,-60.583,-60.583) The Antarctic Weddell Weddell Sea Journal of Physical Oceanography 47 12 2977 2997 |
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Open Polar |
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Caltech Authors (California Institute of Technology) |
op_collection_id |
ftcaltechauth |
language |
English |
description |
The dense water outflow from the Antarctic continental shelf is closely associated with the strength and position of the Antarctic Slope Front. This study explores the short-term and spatial variability of the Antarctic Slope Front system and the mechanisms that regulate cross-slope exchange using highly temporally and spatially resolved measurements from three ocean gliders deployed in 2012. The 22 sections along the eastern Antarctic Peninsula and west of the South Orkney Islands are grouped regionally and composited by isobaths. There is consistency in the front position around the Powell Basin, varying mostly between the 500- and 800-m isobaths. In most of the study area the flow is bottom intensified. The along-slope transport of the Antarctic Slope Current (upper 1000 m) varies between 0.2 and 5.9 Sv (1 Sv ≡ 10^6 m^3 s^(−1)) and does not exhibit a regional pattern. The magnitude of the velocity field shows substantial variability, up to twice its mean value. Higher eddy kinetic energy (0.003 m^2 s^(−2)) is observed in sections with dense water, possibly because of baroclinic instabilities in the bottom layer. Distributions of potential vorticity show an increase toward the shelf along isopycnals and also in the dense water layer. Glider sections located west of the South Orkney Islands indicate a northward direction of the flow associated with the Weddell Front, which differs from previous estimates of the mean circulation. This study provides some of the first observational confirmation of the high-frequency variability associated with an active eddy field that has been suggested by recent numerical simulations in this region. |
format |
Article in Journal/Newspaper |
author |
Azaneu, Marina Heywood, Karen J. Queste, Bastien Y. Thompson, Andrew F. |
spellingShingle |
Azaneu, Marina Heywood, Karen J. Queste, Bastien Y. Thompson, Andrew F. Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea |
author_facet |
Azaneu, Marina Heywood, Karen J. Queste, Bastien Y. Thompson, Andrew F. |
author_sort |
Azaneu, Marina |
title |
Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea |
title_short |
Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea |
title_full |
Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea |
title_fullStr |
Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea |
title_full_unstemmed |
Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea |
title_sort |
variability of the antarctic slope current system in the northwestern weddell sea |
publisher |
American Meteorological Society |
publishDate |
2017 |
url |
https://authors.library.caltech.edu/84079/ https://authors.library.caltech.edu/84079/1/jpo-d-17-0030.1.pdf https://resolver.caltech.edu/CaltechAUTHORS:20180104-124655892 |
long_lat |
ENVELOPE(-49.500,-49.500,-62.250,-62.250) ENVELOPE(-45.500,-45.500,-60.583,-60.583) |
geographic |
Antarctic Antarctic Peninsula Powell Basin South Orkney Islands The Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Antarctic Peninsula Powell Basin South Orkney Islands The Antarctic Weddell Weddell Sea |
genre |
Antarc* Antarctic Antarctic Peninsula South Orkney Islands Weddell Sea |
genre_facet |
Antarc* Antarctic Antarctic Peninsula South Orkney Islands Weddell Sea |
op_relation |
https://authors.library.caltech.edu/84079/1/jpo-d-17-0030.1.pdf Azaneu, Marina and Heywood, Karen J. and Queste, Bastien Y. and Thompson, Andrew F. (2017) Variability of the Antarctic Slope Current System in the Northwestern Weddell Sea. Journal of Physical Oceanography, 47 (12). pp. 2977-2997. ISSN 0022-3670. doi:10.1175/JPO-D-17-0030.1. https://resolver.caltech.edu/CaltechAUTHORS:20180104-124655892 <https://resolver.caltech.edu/CaltechAUTHORS:20180104-124655892> |
op_rights |
cc_by |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1175/JPO-D-17-0030.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
47 |
container_issue |
12 |
container_start_page |
2977 |
op_container_end_page |
2997 |
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1766271774734942208 |