A seasonal climatology of the upper ocean pycnocline
International audience Climatologies of the mixed layer depth (MLD) have been provided using several definitions based on temperature/density thresholds or hybrid approaches. The upper ocean pycnocline (UOP) that sits below the mixed layer base remains poorly characterized, though this transition la...
Published in: | Frontiers in Marine Science |
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Format: | Article in Journal/Newspaper |
Language: | English |
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2023
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ftunivbrest:oai:HAL:insu-04155082v1 2024-04-14T08:04:07+00:00 A seasonal climatology of the upper ocean pycnocline Sérazin, Guillaume Tréguier, Anne Marie de Boyer Montégut, Clément Laboratoire d'Océanographie Physique et Spatiale (LOPS) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS) 2023-03-14 https://insu.hal.science/insu-04155082 https://insu.hal.science/insu-04155082/document https://insu.hal.science/insu-04155082/file/fmars-10-1120112.pdf https://doi.org/10.3389/fmars.2023.1120112 en eng HAL CCSD Frontiers Media info:eu-repo/semantics/altIdentifier/doi/10.3389/fmars.2023.1120112 insu-04155082 https://insu.hal.science/insu-04155082 https://insu.hal.science/insu-04155082/document https://insu.hal.science/insu-04155082/file/fmars-10-1120112.pdf doi:10.3389/fmars.2023.1120112 http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess ISSN: 2296-7745 Frontiers in Marine Science https://insu.hal.science/insu-04155082 Frontiers in Marine Science, 2023, 10, ⟨10.3389/fmars.2023.1120112⟩ upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability [SDU]Sciences of the Universe [physics] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2023 ftunivbrest https://doi.org/10.3389/fmars.2023.1120112 2024-03-21T16:22:40Z International audience Climatologies of the mixed layer depth (MLD) have been provided using several definitions based on temperature/density thresholds or hybrid approaches. The upper ocean pycnocline (UOP) that sits below the mixed layer base remains poorly characterized, though this transition layer is an ubiquitous feature of the ocean surface layer. Available hydrographic profiles provide near-global coverage of the world’s ocean and are used to build a seasonal climatology of UOP properties – intensity, depth, thickness – to characterize the spatial and seasonal variations of upper ocean stratification. The largest stratification values O (10 −3 s −2 ) are found in the intertropical band, where seasonal variations of the UOP are also very small. The deepest (> 200 m) and least stratified O (10 −6 s −2 ) UOPs are found in winter along the Antarctic Circumpolar Current (ACC) and at high latitudes of the North Atlantic. The UOP thickness has a median value of 23 m with limited seasonal and spatial variations; only a few regions have UOP thicknesses exceeding 35 m. The UOP properties allow the characterization of the upper ocean restratification that generally occurs in early spring and is generally associated with large variability. Depending on the region, this restratification may happen gradually as around the Rockall plateau or abruptly as in the Kuroshio Extension. The UOP is also likely to merge intermittently with the permanent pycnocline in winter. The upper edge of the UOP is eventually close to MLD estimates, except in a few notable regions such as in the Pacific Warm Pool where barrier layers are important, and during wintertime at high latitudes of the North Pacific. Article in Journal/Newspaper Antarc* Antarctic North Atlantic Université de Bretagne Occidentale: HAL Antarctic Pacific Rockall Plateau ENVELOPE(-18.833,-18.833,56.333,56.333) The Antarctic Frontiers in Marine Science 10 |
institution |
Open Polar |
collection |
Université de Bretagne Occidentale: HAL |
op_collection_id |
ftunivbrest |
language |
English |
topic |
upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability [SDU]Sciences of the Universe [physics] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability [SDU]Sciences of the Universe [physics] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Sérazin, Guillaume Tréguier, Anne Marie de Boyer Montégut, Clément A seasonal climatology of the upper ocean pycnocline |
topic_facet |
upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability upper ocean stratification mixed layer depth boundary layer air-sea exchanges seasonal variability [SDU]Sciences of the Universe [physics] [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience Climatologies of the mixed layer depth (MLD) have been provided using several definitions based on temperature/density thresholds or hybrid approaches. The upper ocean pycnocline (UOP) that sits below the mixed layer base remains poorly characterized, though this transition layer is an ubiquitous feature of the ocean surface layer. Available hydrographic profiles provide near-global coverage of the world’s ocean and are used to build a seasonal climatology of UOP properties – intensity, depth, thickness – to characterize the spatial and seasonal variations of upper ocean stratification. The largest stratification values O (10 −3 s −2 ) are found in the intertropical band, where seasonal variations of the UOP are also very small. The deepest (> 200 m) and least stratified O (10 −6 s −2 ) UOPs are found in winter along the Antarctic Circumpolar Current (ACC) and at high latitudes of the North Atlantic. The UOP thickness has a median value of 23 m with limited seasonal and spatial variations; only a few regions have UOP thicknesses exceeding 35 m. The UOP properties allow the characterization of the upper ocean restratification that generally occurs in early spring and is generally associated with large variability. Depending on the region, this restratification may happen gradually as around the Rockall plateau or abruptly as in the Kuroshio Extension. The UOP is also likely to merge intermittently with the permanent pycnocline in winter. The upper edge of the UOP is eventually close to MLD estimates, except in a few notable regions such as in the Pacific Warm Pool where barrier layers are important, and during wintertime at high latitudes of the North Pacific. |
author2 |
Laboratoire d'Océanographie Physique et Spatiale (LOPS) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Sérazin, Guillaume Tréguier, Anne Marie de Boyer Montégut, Clément |
author_facet |
Sérazin, Guillaume Tréguier, Anne Marie de Boyer Montégut, Clément |
author_sort |
Sérazin, Guillaume |
title |
A seasonal climatology of the upper ocean pycnocline |
title_short |
A seasonal climatology of the upper ocean pycnocline |
title_full |
A seasonal climatology of the upper ocean pycnocline |
title_fullStr |
A seasonal climatology of the upper ocean pycnocline |
title_full_unstemmed |
A seasonal climatology of the upper ocean pycnocline |
title_sort |
seasonal climatology of the upper ocean pycnocline |
publisher |
HAL CCSD |
publishDate |
2023 |
url |
https://insu.hal.science/insu-04155082 https://insu.hal.science/insu-04155082/document https://insu.hal.science/insu-04155082/file/fmars-10-1120112.pdf https://doi.org/10.3389/fmars.2023.1120112 |
long_lat |
ENVELOPE(-18.833,-18.833,56.333,56.333) |
geographic |
Antarctic Pacific Rockall Plateau The Antarctic |
geographic_facet |
Antarctic Pacific Rockall Plateau The Antarctic |
genre |
Antarc* Antarctic North Atlantic |
genre_facet |
Antarc* Antarctic North Atlantic |
op_source |
ISSN: 2296-7745 Frontiers in Marine Science https://insu.hal.science/insu-04155082 Frontiers in Marine Science, 2023, 10, ⟨10.3389/fmars.2023.1120112⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3389/fmars.2023.1120112 insu-04155082 https://insu.hal.science/insu-04155082 https://insu.hal.science/insu-04155082/document https://insu.hal.science/insu-04155082/file/fmars-10-1120112.pdf doi:10.3389/fmars.2023.1120112 |
op_rights |
http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.3389/fmars.2023.1120112 |
container_title |
Frontiers in Marine Science |
container_volume |
10 |
_version_ |
1796300503844388864 |