Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting
The ocean's internal pycnocline is a layer of elevated stratification that separates the well-ventilated upper ocean from the more slowly renewed deep ocean. Despite its pivotal role in organizing ocean circulation, the processes governing the formation of the internal pycnocline remain little...
Published in: | Journal of Geophysical Research: Oceans |
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Online Access: | https://hdl.handle.net/11250/3084552 https://doi.org/10.1029/2022JC019113 |
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ftnorce:oai:norceresearch.brage.unit.no:11250/3084552 2023-09-05T13:13:11+02:00 Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting Klocker, Andreas Naveira-Garabato, Alberto C Roquet, Fabien de Lavergne, Casimir Rintoul, Steve 2023 application/pdf https://hdl.handle.net/11250/3084552 https://doi.org/10.1029/2022JC019113 eng eng Journal of Geophysical Research (JGR): Oceans. 2023, 128 (3), . urn:issn:2169-9275 https://hdl.handle.net/11250/3084552 https://doi.org/10.1029/2022JC019113 cristin:2137872 Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal http://creativecommons.org/licenses/by-nc-nd/4.0/deed.no © 2023 The Authors Journal of Geophysical Research (JGR): Oceans 128 3 15 Peer reviewed Journal article 2023 ftnorce https://doi.org/10.1029/2022JC019113 2023-08-23T22:49:25Z The ocean's internal pycnocline is a layer of elevated stratification that separates the well-ventilated upper ocean from the more slowly renewed deep ocean. Despite its pivotal role in organizing ocean circulation, the processes governing the formation of the internal pycnocline remain little understood. Classical theories on pycnocline formation have been couched in terms of temperature and it is not clear how the theory applies in the high-latitude Southern Ocean, where stratification is dominated by salinity. Here we assess the mechanisms generating the internal pycnocline at southern high latitudes through the analysis of a high-resolution, realistic, global sea ice–ocean model. We show evidence suggesting that the internal pycnocline's formation is associated with sea ice-ocean interactions in two distinct ice-covered regions, fringing the Antarctic continental slope and the winter sea-ice edge. In both areas, winter-persistent sea-ice melt creates strong, salinity-based stratification at the base of the winter mixed layer. The resulting sheets of high stratification subsequently descend into the ocean interior at fronts of the Antarctic Circumpolar Current, and connect seamlessly to the internal pycnocline in areas further north in which pycnocline stratification is determined by temperature. Our findings thus suggest an important role of localized sea ice-ocean interactions in configuring the vertical structure of the Southern Ocean. publishedVersion Article in Journal/Newspaper Antarc* Antarctic Sea ice Southern Ocean NORCE vitenarkiv (Norwegian Research Centre) Antarctic Southern Ocean The Antarctic Journal of Geophysical Research: Oceans 128 3 |
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Open Polar |
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NORCE vitenarkiv (Norwegian Research Centre) |
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ftnorce |
language |
English |
description |
The ocean's internal pycnocline is a layer of elevated stratification that separates the well-ventilated upper ocean from the more slowly renewed deep ocean. Despite its pivotal role in organizing ocean circulation, the processes governing the formation of the internal pycnocline remain little understood. Classical theories on pycnocline formation have been couched in terms of temperature and it is not clear how the theory applies in the high-latitude Southern Ocean, where stratification is dominated by salinity. Here we assess the mechanisms generating the internal pycnocline at southern high latitudes through the analysis of a high-resolution, realistic, global sea ice–ocean model. We show evidence suggesting that the internal pycnocline's formation is associated with sea ice-ocean interactions in two distinct ice-covered regions, fringing the Antarctic continental slope and the winter sea-ice edge. In both areas, winter-persistent sea-ice melt creates strong, salinity-based stratification at the base of the winter mixed layer. The resulting sheets of high stratification subsequently descend into the ocean interior at fronts of the Antarctic Circumpolar Current, and connect seamlessly to the internal pycnocline in areas further north in which pycnocline stratification is determined by temperature. Our findings thus suggest an important role of localized sea ice-ocean interactions in configuring the vertical structure of the Southern Ocean. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Klocker, Andreas Naveira-Garabato, Alberto C Roquet, Fabien de Lavergne, Casimir Rintoul, Steve |
spellingShingle |
Klocker, Andreas Naveira-Garabato, Alberto C Roquet, Fabien de Lavergne, Casimir Rintoul, Steve Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting |
author_facet |
Klocker, Andreas Naveira-Garabato, Alberto C Roquet, Fabien de Lavergne, Casimir Rintoul, Steve |
author_sort |
Klocker, Andreas |
title |
Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting |
title_short |
Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting |
title_full |
Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting |
title_fullStr |
Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting |
title_full_unstemmed |
Generation of the Internal Pycnocline in the Subpolar Southern Ocean by Wintertime Sea Ice Melting |
title_sort |
generation of the internal pycnocline in the subpolar southern ocean by wintertime sea ice melting |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3084552 https://doi.org/10.1029/2022JC019113 |
geographic |
Antarctic Southern Ocean The Antarctic |
geographic_facet |
Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Sea ice Southern Ocean |
op_source |
Journal of Geophysical Research (JGR): Oceans 128 3 15 |
op_relation |
Journal of Geophysical Research (JGR): Oceans. 2023, 128 (3), . urn:issn:2169-9275 https://hdl.handle.net/11250/3084552 https://doi.org/10.1029/2022JC019113 cristin:2137872 |
op_rights |
Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal http://creativecommons.org/licenses/by-nc-nd/4.0/deed.no © 2023 The Authors |
op_doi |
https://doi.org/10.1029/2022JC019113 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
128 |
container_issue |
3 |
_version_ |
1776203935519866880 |