A linear decomposition of the Southern Ocean thermohaline structure
The thermohaline structure of the Southern Ocean is deeply influenced by the presence of the Antarctic Circumpolar Current (ACC), where water masses of the World Ocean are advected, transformed, and redistributed to the other basins. It remains a challenge to describe and visualize the complex 3D pa...
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ftnerc:oai:nora.nerc.ac.uk:516295 2023-05-15T13:49:33+02:00 A linear decomposition of the Southern Ocean thermohaline structure Pauthenet, Etienne Roquet, Fabien Madec, Gurvan Nerini, David 2017-01-01 text http://nora.nerc.ac.uk/id/eprint/516295/ https://nora.nerc.ac.uk/id/eprint/516295/1/jpo-d-16-0083%252E1.pdf https://doi.org/10.1175/JPO-D-16-0083.1 en eng https://nora.nerc.ac.uk/id/eprint/516295/1/jpo-d-16-0083%252E1.pdf Pauthenet, Etienne; Roquet, Fabien; Madec, Gurvan; Nerini, David. 2017 A linear decomposition of the Southern Ocean thermohaline structure. Journal of Physical Oceanography, 47 (1). 29-47. https://doi.org/10.1175/JPO-D-16-0083.1 <https://doi.org/10.1175/JPO-D-16-0083.1> Publication - Article PeerReviewed 2017 ftnerc https://doi.org/10.1175/JPO-D-16-0083.1 2023-02-04T19:44:32Z The thermohaline structure of the Southern Ocean is deeply influenced by the presence of the Antarctic Circumpolar Current (ACC), where water masses of the World Ocean are advected, transformed, and redistributed to the other basins. It remains a challenge to describe and visualize the complex 3D pattern of this circulation and its associated tracer distribution. Here, a simple framework is presented to analyze the Southern Ocean thermohaline structure. A functional principal component analysis (PCA) is applied to temperature θ and salinity S profiles to determine the main spatial patterns of their variations. Using the Southern Ocean State Estimate (SOSE), this study determines the vertical modes describing the Southern Ocean thermohaline structure between 5 and 2000 m. The first two modes explain 92% of the combined θ–S variance, thus providing a surprisingly good approximation of the thermohaline properties in the Southern Ocean. The first mode (72% of total variance) accurately describes the north–south property gradients. The second mode (20%) mostly describes salinity at 500 m in the region of Antarctic Intermediate Water formation. These two modes present circumpolar patterns that can be closely related with standard frontal definitions. By projecting any given hydrographic profile onto the SOSE-based modes, it is possible to determine its position relative to the fronts. The projection is successfully applied on the hydrographic profiles of the WOCE SR3 section. The Southern Ocean thermohaline decomposition provides an objective way to define water mass boundaries and their spatial variability and has useful application for comparing model output with observations. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean Natural Environment Research Council: NERC Open Research Archive Antarctic Southern Ocean The Antarctic Journal of Physical Oceanography 47 1 29 47 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
The thermohaline structure of the Southern Ocean is deeply influenced by the presence of the Antarctic Circumpolar Current (ACC), where water masses of the World Ocean are advected, transformed, and redistributed to the other basins. It remains a challenge to describe and visualize the complex 3D pattern of this circulation and its associated tracer distribution. Here, a simple framework is presented to analyze the Southern Ocean thermohaline structure. A functional principal component analysis (PCA) is applied to temperature θ and salinity S profiles to determine the main spatial patterns of their variations. Using the Southern Ocean State Estimate (SOSE), this study determines the vertical modes describing the Southern Ocean thermohaline structure between 5 and 2000 m. The first two modes explain 92% of the combined θ–S variance, thus providing a surprisingly good approximation of the thermohaline properties in the Southern Ocean. The first mode (72% of total variance) accurately describes the north–south property gradients. The second mode (20%) mostly describes salinity at 500 m in the region of Antarctic Intermediate Water formation. These two modes present circumpolar patterns that can be closely related with standard frontal definitions. By projecting any given hydrographic profile onto the SOSE-based modes, it is possible to determine its position relative to the fronts. The projection is successfully applied on the hydrographic profiles of the WOCE SR3 section. The Southern Ocean thermohaline decomposition provides an objective way to define water mass boundaries and their spatial variability and has useful application for comparing model output with observations. |
format |
Article in Journal/Newspaper |
author |
Pauthenet, Etienne Roquet, Fabien Madec, Gurvan Nerini, David |
spellingShingle |
Pauthenet, Etienne Roquet, Fabien Madec, Gurvan Nerini, David A linear decomposition of the Southern Ocean thermohaline structure |
author_facet |
Pauthenet, Etienne Roquet, Fabien Madec, Gurvan Nerini, David |
author_sort |
Pauthenet, Etienne |
title |
A linear decomposition of the Southern Ocean thermohaline structure |
title_short |
A linear decomposition of the Southern Ocean thermohaline structure |
title_full |
A linear decomposition of the Southern Ocean thermohaline structure |
title_fullStr |
A linear decomposition of the Southern Ocean thermohaline structure |
title_full_unstemmed |
A linear decomposition of the Southern Ocean thermohaline structure |
title_sort |
linear decomposition of the southern ocean thermohaline structure |
publishDate |
2017 |
url |
http://nora.nerc.ac.uk/id/eprint/516295/ https://nora.nerc.ac.uk/id/eprint/516295/1/jpo-d-16-0083%252E1.pdf https://doi.org/10.1175/JPO-D-16-0083.1 |
geographic |
Antarctic Southern Ocean The Antarctic |
geographic_facet |
Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_relation |
https://nora.nerc.ac.uk/id/eprint/516295/1/jpo-d-16-0083%252E1.pdf Pauthenet, Etienne; Roquet, Fabien; Madec, Gurvan; Nerini, David. 2017 A linear decomposition of the Southern Ocean thermohaline structure. Journal of Physical Oceanography, 47 (1). 29-47. https://doi.org/10.1175/JPO-D-16-0083.1 <https://doi.org/10.1175/JPO-D-16-0083.1> |
op_doi |
https://doi.org/10.1175/JPO-D-16-0083.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
47 |
container_issue |
1 |
container_start_page |
29 |
op_container_end_page |
47 |
_version_ |
1766251645031677952 |