Eddy response to Southern Ocean climate modes
International audience Interannual variations in Southern Ocean eddy kinetic energy (EKE) are investigated using 16 years of altimetric data. Circumpolar averages show a peak in EKE from 2000 to 2002, 2-3 years after the peak in the Southern Annular Mode (SAM) index. Although the SAM forcing is in p...
Published in: | Journal of Geophysical Research: Oceans |
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Main Authors: | , , , |
Other Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2010
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Online Access: | https://hal.science/hal-00798759 https://hal.science/hal-00798759/document https://hal.science/hal-00798759/file/jgrc11594.pdf https://doi.org/10.1029/2009JC005894 |
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Open Polar |
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Institut national des sciences de l'Univers: HAL-INSU |
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English |
topic |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
spellingShingle |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere Morrow, Rosemary Ward, Marshall Hogg, Andrew Mcc. Pasquet, S. Eddy response to Southern Ocean climate modes |
topic_facet |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
description |
International audience Interannual variations in Southern Ocean eddy kinetic energy (EKE) are investigated using 16 years of altimetric data. Circumpolar averages show a peak in EKE from 2000 to 2002, 2-3 years after the peak in the Southern Annular Mode (SAM) index. Although the SAM forcing is in phase around the circumpolar band, we find the EKE response varies regionally. The strongest EKE is in the Pacific, with energy peaks occurring progressively later toward the east. We suggest that this is due to the presence of two climate modes: SAM and ENSO. When strong positive SAM events coincide with La Niña periods, as in 1999, anomalous meridional wind forcing is enhanced in the South Pacific Ocean, contributing to the observed increase in EKE 2-3 years later. When positive SAM events coincide with El Niño periods, as in 1993, the climate modes are in opposition in the South Pacific, leading to a weak EKE response during the mid-1990s. Numerical modeling supports these observations. By applying different combinations of SAM and ENSO, we can reproduce both the elevated Pacific EKE response to SAM as well as an additional amplification/suppression of EKE during La Niña/El Niño. In general, we find that the EKE response depends on the interplay between wind forcing, topography, and mean flow and produces a strongly heterogeneous distribution in the Southern Ocean. |
author2 |
Océan du Large et Variabilité Climatique (OLVAC) Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) Research School of Earth Sciences Canberra (RSES) Australian National University (ANU) |
format |
Article in Journal/Newspaper |
author |
Morrow, Rosemary Ward, Marshall Hogg, Andrew Mcc. Pasquet, S. |
author_facet |
Morrow, Rosemary Ward, Marshall Hogg, Andrew Mcc. Pasquet, S. |
author_sort |
Morrow, Rosemary |
title |
Eddy response to Southern Ocean climate modes |
title_short |
Eddy response to Southern Ocean climate modes |
title_full |
Eddy response to Southern Ocean climate modes |
title_fullStr |
Eddy response to Southern Ocean climate modes |
title_full_unstemmed |
Eddy response to Southern Ocean climate modes |
title_sort |
eddy response to southern ocean climate modes |
publisher |
HAL CCSD |
publishDate |
2010 |
url |
https://hal.science/hal-00798759 https://hal.science/hal-00798759/document https://hal.science/hal-00798759/file/jgrc11594.pdf https://doi.org/10.1029/2009JC005894 |
geographic |
Pacific Southern Ocean |
geographic_facet |
Pacific Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
ISSN: 0148-0227 EISSN: 2156-2202 Journal of Geophysical Research https://hal.science/hal-00798759 Journal of Geophysical Research, 2010, 115 (C10), pp.C10030. ⟨10.1029/2009JC005894⟩ |
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op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2009JC005894 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
115 |
container_issue |
C10 |
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1785575201955643392 |
spelling |
ftinsu:oai:HAL:hal-00798759v1 2023-12-17T10:50:24+01:00 Eddy response to Southern Ocean climate modes Morrow, Rosemary Ward, Marshall Hogg, Andrew Mcc. Pasquet, S. Océan du Large et Variabilité Climatique (OLVAC) Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) Research School of Earth Sciences Canberra (RSES) Australian National University (ANU) 2010-10 https://hal.science/hal-00798759 https://hal.science/hal-00798759/document https://hal.science/hal-00798759/file/jgrc11594.pdf https://doi.org/10.1029/2009JC005894 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2009JC005894 hal-00798759 https://hal.science/hal-00798759 https://hal.science/hal-00798759/document https://hal.science/hal-00798759/file/jgrc11594.pdf doi:10.1029/2009JC005894 info:eu-repo/semantics/OpenAccess ISSN: 0148-0227 EISSN: 2156-2202 Journal of Geophysical Research https://hal.science/hal-00798759 Journal of Geophysical Research, 2010, 115 (C10), pp.C10030. ⟨10.1029/2009JC005894⟩ [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere info:eu-repo/semantics/article Journal articles 2010 ftinsu https://doi.org/10.1029/2009JC005894 2023-11-22T17:23:32Z International audience Interannual variations in Southern Ocean eddy kinetic energy (EKE) are investigated using 16 years of altimetric data. Circumpolar averages show a peak in EKE from 2000 to 2002, 2-3 years after the peak in the Southern Annular Mode (SAM) index. Although the SAM forcing is in phase around the circumpolar band, we find the EKE response varies regionally. The strongest EKE is in the Pacific, with energy peaks occurring progressively later toward the east. We suggest that this is due to the presence of two climate modes: SAM and ENSO. When strong positive SAM events coincide with La Niña periods, as in 1999, anomalous meridional wind forcing is enhanced in the South Pacific Ocean, contributing to the observed increase in EKE 2-3 years later. When positive SAM events coincide with El Niño periods, as in 1993, the climate modes are in opposition in the South Pacific, leading to a weak EKE response during the mid-1990s. Numerical modeling supports these observations. By applying different combinations of SAM and ENSO, we can reproduce both the elevated Pacific EKE response to SAM as well as an additional amplification/suppression of EKE during La Niña/El Niño. In general, we find that the EKE response depends on the interplay between wind forcing, topography, and mean flow and produces a strongly heterogeneous distribution in the Southern Ocean. Article in Journal/Newspaper Southern Ocean Institut national des sciences de l'Univers: HAL-INSU Pacific Southern Ocean Journal of Geophysical Research: Oceans 115 C10 |