Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade
Using an Argo dataset and the ECCOv4 reanalysis, a volume budget was performed to address the main mechanisms driving the volume change of the interior water masses in the Southern Hemisphere oceans between 2006 and 2015. The subduction rates and the isopycnal and diapycnal water-mass transformation...
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fttriple:oai:gotriple.eu:10670/1.av28a1 2023-05-15T13:38:44+02:00 Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade Portela, Esther Kolodziejczyk, Nicolas Maes, Christophe Thierry, Virginie 2020-01-01 https://doi.org/10.1175/JPO-D-19-0128.1 https://archimer.ifremer.fr/doc/00609/72065/70771.pdf https://archimer.ifremer.fr/doc/00609/72065/70772.pdf https://archimer.ifremer.fr/doc/00609/72065/ en eng Amer Meteorological Soc doi:10.1175/JPO-D-19-0128.1 10670/1.av28a1 https://archimer.ifremer.fr/doc/00609/72065/70771.pdf https://archimer.ifremer.fr/doc/00609/72065/70772.pdf https://archimer.ifremer.fr/doc/00609/72065/ Archimer, archive institutionnelle de l'Ifremer Journal Of Physical Oceanography (0022-3670) (Amer Meteorological Soc), 2020-02 , Vol. 50 , N. 2 , P. 361-381 geo envir Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ 2020 fttriple https://doi.org/10.1175/JPO-D-19-0128.1 2023-01-22T17:10:41Z Using an Argo dataset and the ECCOv4 reanalysis, a volume budget was performed to address the main mechanisms driving the volume change of the interior water masses in the Southern Hemisphere oceans between 2006 and 2015. The subduction rates and the isopycnal and diapycnal water-mass transformation were estimated in a density-spiciness (sigma-tau) framework. Spiciness, defined as thermohaline variations along isopycnals, was added to the potential density coordinates to discriminate between water masses spreading on isopycnal layers. The main positive volume trends were found to be associated with the Subantarctic Mode Waters (SAMW) in the South Pacific and South Indian Ocean basins, revealing a lightening of the upper waters in the Southern Hemisphere. The SAMW exhibits a two-layer density structure in which subduction and diapycnal transformation from the lower to the upper layers accounted for most of the upper-layer volume gain and lower-layer volume loss, respectively. The Antarctic Intermediate Waters, defined here between the 27.2 and 27.5 kg m(-3) isopycnals, showed the strongest negative volume trends. This volume loss can be explained by their negative isopyncal transformation southward of the Antarctic Circumpolar Current into the fresher and colder Antarctic Winter Waters (AAWW) and northward into spicier tropical/subtropical Intermediate Waters. The AAWW is destroyed by obduction back into the mixed layer so that its net volume change remains nearly zero. The proposed mechanisms to explain the transformation within the Intermediate Waters are discussed in the context of Southern Ocean dynamics. The sigma-tau decomposition provided new insight on the spatial and temporal water-mass variability and driving mechanisms over the last decade. Text Antarc* Antarctic Southern Ocean Unknown Antarctic Indian Pacific Southern Ocean The Antarctic Journal of Physical Oceanography 50 2 361 381 |
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English |
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geo envir Portela, Esther Kolodziejczyk, Nicolas Maes, Christophe Thierry, Virginie Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade |
topic_facet |
geo envir |
description |
Using an Argo dataset and the ECCOv4 reanalysis, a volume budget was performed to address the main mechanisms driving the volume change of the interior water masses in the Southern Hemisphere oceans between 2006 and 2015. The subduction rates and the isopycnal and diapycnal water-mass transformation were estimated in a density-spiciness (sigma-tau) framework. Spiciness, defined as thermohaline variations along isopycnals, was added to the potential density coordinates to discriminate between water masses spreading on isopycnal layers. The main positive volume trends were found to be associated with the Subantarctic Mode Waters (SAMW) in the South Pacific and South Indian Ocean basins, revealing a lightening of the upper waters in the Southern Hemisphere. The SAMW exhibits a two-layer density structure in which subduction and diapycnal transformation from the lower to the upper layers accounted for most of the upper-layer volume gain and lower-layer volume loss, respectively. The Antarctic Intermediate Waters, defined here between the 27.2 and 27.5 kg m(-3) isopycnals, showed the strongest negative volume trends. This volume loss can be explained by their negative isopyncal transformation southward of the Antarctic Circumpolar Current into the fresher and colder Antarctic Winter Waters (AAWW) and northward into spicier tropical/subtropical Intermediate Waters. The AAWW is destroyed by obduction back into the mixed layer so that its net volume change remains nearly zero. The proposed mechanisms to explain the transformation within the Intermediate Waters are discussed in the context of Southern Ocean dynamics. The sigma-tau decomposition provided new insight on the spatial and temporal water-mass variability and driving mechanisms over the last decade. |
format |
Text |
author |
Portela, Esther Kolodziejczyk, Nicolas Maes, Christophe Thierry, Virginie |
author_facet |
Portela, Esther Kolodziejczyk, Nicolas Maes, Christophe Thierry, Virginie |
author_sort |
Portela, Esther |
title |
Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade |
title_short |
Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade |
title_full |
Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade |
title_fullStr |
Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade |
title_full_unstemmed |
Interior Water-Mass Variability in the Southern Hemisphere Oceans during the Last Decade |
title_sort |
interior water-mass variability in the southern hemisphere oceans during the last decade |
publisher |
Amer Meteorological Soc |
publishDate |
2020 |
url |
https://doi.org/10.1175/JPO-D-19-0128.1 https://archimer.ifremer.fr/doc/00609/72065/70771.pdf https://archimer.ifremer.fr/doc/00609/72065/70772.pdf https://archimer.ifremer.fr/doc/00609/72065/ |
geographic |
Antarctic Indian Pacific Southern Ocean The Antarctic |
geographic_facet |
Antarctic Indian Pacific Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
Archimer, archive institutionnelle de l'Ifremer Journal Of Physical Oceanography (0022-3670) (Amer Meteorological Soc), 2020-02 , Vol. 50 , N. 2 , P. 361-381 |
op_relation |
doi:10.1175/JPO-D-19-0128.1 10670/1.av28a1 https://archimer.ifremer.fr/doc/00609/72065/70771.pdf https://archimer.ifremer.fr/doc/00609/72065/70772.pdf https://archimer.ifremer.fr/doc/00609/72065/ |
op_doi |
https://doi.org/10.1175/JPO-D-19-0128.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
50 |
container_issue |
2 |
container_start_page |
361 |
op_container_end_page |
381 |
_version_ |
1766110536969224192 |