Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean
<jats:title>Abstract</jats:title><jats:p>Seismic reflection images of thermohaline circulation from the Bellingshausen Sea, adjacent to the West Antarctica Peninsula, were acquired during February 2015. This survey shows that bright reflectivity occurs throughout the upper 300 m. B...
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ftunivcam:oai:www.repository.cam.ac.uk:1810/277319 2024-01-14T09:58:57+01:00 Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean Gunn, KL White, NJ Larter, RD Caulfield, CP 2018 application/octet-stream https://www.repository.cam.ac.uk/handle/1810/277319 https://doi.org/10.17863/CAM.24608 eng eng American Geophysical Union (AGU) http://dx.doi.org/10.1029/2018jc013833 Journal of Geophysical Research: Oceans https://www.repository.cam.ac.uk/handle/1810/277319 doi:10.17863/CAM.24608 seismic oceanography Bellingshausen Sea warm-core eddies ice-shelf basal melt Antarctic Slope Front Article 2018 ftunivcam https://doi.org/10.17863/CAM.24608 2023-12-21T23:28:48Z <jats:title>Abstract</jats:title><jats:p>Seismic reflection images of thermohaline circulation from the Bellingshausen Sea, adjacent to the West Antarctica Peninsula, were acquired during February 2015. This survey shows that bright reflectivity occurs throughout the upper 300 m. By calibrating these seismic images with coeval hydrographic measurements, intrusion of warm water features onto the continental shelf at Marguerite and Belgica Troughs is identified and characterized. These features have distinctive lens‐shaped patterns of reflectivity with lengths of 0.75–11.00 km and thicknesses of 100–150 m, suggesting that they are small mesoscale to submesoscale eddies. Abundant eddies are observed along a transect that crosses Belgica Trough. Near Alexander Island Drift, a large, of order <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/jgrc22803-math-0001.png" xlink:title="urn:x-wiley:21699275:media:jgrc22803:jgrc22803-math-0001" /> km<jats:sup>3</jats:sup>, bowl‐like feature, that may represent an anticyclonic Taylor column, is imaged on a pair of orthogonal images. A modified iterative procedure is used to convert seismic imagery into maps of temperature that enable the number and size of eddies being transported onto the shelf to be quantified. Finally, analysis of prestack shot records suggests that these eddies are advecting southward at speeds of <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/jgrc22803-math-0002.png" xlink:title="urn:x-wiley:21699275:media:jgrc22803:jgrc22803-math-0002" /> m s<jats:sup>−1</jats:sup>, consistent with limited legacy hydrographic measurements. Concentration of observed eddies south of the Southern Antarctic Circumpolar Current Front implies they represent both a dominant, and a long‐lived, mechanism of warm‐water transport, especially across Belgica Trough. Our observations suggest that previous estimates of eddy frequency may have been underestimated ... Article in Journal/Newspaper Alexander Island Antarc* Antarctic Antarctica Bellingshausen Sea Ice Shelf Southern Ocean West Antarctica Apollo - University of Cambridge Repository Alexander Island ENVELOPE(-69.895,-69.895,-71.287,-71.287) Antarctic Bellingshausen Sea Marguerite ENVELOPE(141.378,141.378,-66.787,-66.787) Southern Ocean West Antarctica |
institution |
Open Polar |
collection |
Apollo - University of Cambridge Repository |
op_collection_id |
ftunivcam |
language |
English |
topic |
seismic oceanography Bellingshausen Sea warm-core eddies ice-shelf basal melt Antarctic Slope Front |
spellingShingle |
seismic oceanography Bellingshausen Sea warm-core eddies ice-shelf basal melt Antarctic Slope Front Gunn, KL White, NJ Larter, RD Caulfield, CP Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean |
topic_facet |
seismic oceanography Bellingshausen Sea warm-core eddies ice-shelf basal melt Antarctic Slope Front |
description |
<jats:title>Abstract</jats:title><jats:p>Seismic reflection images of thermohaline circulation from the Bellingshausen Sea, adjacent to the West Antarctica Peninsula, were acquired during February 2015. This survey shows that bright reflectivity occurs throughout the upper 300 m. By calibrating these seismic images with coeval hydrographic measurements, intrusion of warm water features onto the continental shelf at Marguerite and Belgica Troughs is identified and characterized. These features have distinctive lens‐shaped patterns of reflectivity with lengths of 0.75–11.00 km and thicknesses of 100–150 m, suggesting that they are small mesoscale to submesoscale eddies. Abundant eddies are observed along a transect that crosses Belgica Trough. Near Alexander Island Drift, a large, of order <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/jgrc22803-math-0001.png" xlink:title="urn:x-wiley:21699275:media:jgrc22803:jgrc22803-math-0001" /> km<jats:sup>3</jats:sup>, bowl‐like feature, that may represent an anticyclonic Taylor column, is imaged on a pair of orthogonal images. A modified iterative procedure is used to convert seismic imagery into maps of temperature that enable the number and size of eddies being transported onto the shelf to be quantified. Finally, analysis of prestack shot records suggests that these eddies are advecting southward at speeds of <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/jgrc22803-math-0002.png" xlink:title="urn:x-wiley:21699275:media:jgrc22803:jgrc22803-math-0002" /> m s<jats:sup>−1</jats:sup>, consistent with limited legacy hydrographic measurements. Concentration of observed eddies south of the Southern Antarctic Circumpolar Current Front implies they represent both a dominant, and a long‐lived, mechanism of warm‐water transport, especially across Belgica Trough. Our observations suggest that previous estimates of eddy frequency may have been underestimated ... |
format |
Article in Journal/Newspaper |
author |
Gunn, KL White, NJ Larter, RD Caulfield, CP |
author_facet |
Gunn, KL White, NJ Larter, RD Caulfield, CP |
author_sort |
Gunn, KL |
title |
Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean |
title_short |
Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean |
title_full |
Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean |
title_fullStr |
Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean |
title_full_unstemmed |
Calibrated Seismic Imaging of Eddy-Dominated Warm-Water Transport Across the Bellingshausen Sea, Southern Ocean |
title_sort |
calibrated seismic imaging of eddy-dominated warm-water transport across the bellingshausen sea, southern ocean |
publisher |
American Geophysical Union (AGU) |
publishDate |
2018 |
url |
https://www.repository.cam.ac.uk/handle/1810/277319 https://doi.org/10.17863/CAM.24608 |
long_lat |
ENVELOPE(-69.895,-69.895,-71.287,-71.287) ENVELOPE(141.378,141.378,-66.787,-66.787) |
geographic |
Alexander Island Antarctic Bellingshausen Sea Marguerite Southern Ocean West Antarctica |
geographic_facet |
Alexander Island Antarctic Bellingshausen Sea Marguerite Southern Ocean West Antarctica |
genre |
Alexander Island Antarc* Antarctic Antarctica Bellingshausen Sea Ice Shelf Southern Ocean West Antarctica |
genre_facet |
Alexander Island Antarc* Antarctic Antarctica Bellingshausen Sea Ice Shelf Southern Ocean West Antarctica |
op_relation |
https://www.repository.cam.ac.uk/handle/1810/277319 doi:10.17863/CAM.24608 |
op_doi |
https://doi.org/10.17863/CAM.24608 |
_version_ |
1788067078359482368 |