Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity
International audience Primary productivity in the Southern Ocean plays a key role in global biogeochemical cycles. While much focus has been placed on phytoplankton production seasonality, non-seasonal fluctuations exceed the amplitude of the seasonal cycle across large swaths of the Antarctic Circ...
Published in: | Global Biogeochemical Cycles |
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Main Authors: | , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2022
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Online Access: | https://hal.science/hal-03705774 https://hal.science/hal-03705774/document https://hal.science/hal-03705774/file/Prend_etal-submitted3.pdf https://doi.org/10.1029/2022GB007329 |
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Open Polar |
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Portail HAL-ANR (Agence Nationale de la Recherche) |
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ftanrparis |
language |
English |
topic |
[SDE]Environmental Sciences |
spellingShingle |
[SDE]Environmental Sciences Prend, Channing J. Keerthi, Madhavan Girijakumari Lévy, Marina Aumont, Olivier Gille, Sarah T. Talley, Lynne D. Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity |
topic_facet |
[SDE]Environmental Sciences |
description |
International audience Primary productivity in the Southern Ocean plays a key role in global biogeochemical cycles. While much focus has been placed on phytoplankton production seasonality, non-seasonal fluctuations exceed the amplitude of the seasonal cycle across large swaths of the Antarctic Circumpolar Current. This non-seasonal variability comprises a broad range of timescales from sub-seasonal (<3 months) to multi-annual (>1 year), all of which can project onto the annual mean value. However, year-to-year variations of surface chlorophyll (SChl), a proxy for phytoplankton biomass, are typically attributed to ocean circulation changes associated with the Southern Annular Mode (SAM), which implicitly assumes that sub-seasonal variability averages to near-zero over long timescales. Here, we test this assumption by applying a timeseries decomposition method to satellite-derived SChl in order to separate the low-frequency and high-frequency contributions to the non-seasonal variability. We find that throughout most of the Southern Ocean, year-to-year SChl variations are dominated by the sub-seasonal component, which is not strongly correlated with the SAM. The multi-annual component, while correlated with the SAM, only accounts for about 10% of the total SChl variance. This suggests that changes in annual mean SChl are related to intermittent forcing at small scales, rather than low-frequency climate variability, and thus do not remain correlated over large regions. |
author2 |
The Scripps Research Institute La Jolla, San Diego Processus et interactions de fine échelle océanique (PROTEO) Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN) Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) École normale supérieure - Paris (ENS-PSL) Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL) Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) ANR-16-CE01-0014,SOBUMS,Comprendre la réponse du cycle du carbone dans l'océan austral au stress climatique(2016) |
format |
Article in Journal/Newspaper |
author |
Prend, Channing J. Keerthi, Madhavan Girijakumari Lévy, Marina Aumont, Olivier Gille, Sarah T. Talley, Lynne D. |
author_facet |
Prend, Channing J. Keerthi, Madhavan Girijakumari Lévy, Marina Aumont, Olivier Gille, Sarah T. Talley, Lynne D. |
author_sort |
Prend, Channing J. |
title |
Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity |
title_short |
Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity |
title_full |
Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity |
title_fullStr |
Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity |
title_full_unstemmed |
Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity |
title_sort |
sub-seasonal forcing drives year-to-year variations of southern ocean primary productivity |
publisher |
HAL CCSD |
publishDate |
2022 |
url |
https://hal.science/hal-03705774 https://hal.science/hal-03705774/document https://hal.science/hal-03705774/file/Prend_etal-submitted3.pdf https://doi.org/10.1029/2022GB007329 |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
ISSN: 0886-6236 EISSN: 1944-8224 Global Biogeochemical Cycles https://hal.science/hal-03705774 Global Biogeochemical Cycles, 2022, 36 (7), pp.e2022GB007329. ⟨10.1029/2022GB007329⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2022GB007329 hal-03705774 https://hal.science/hal-03705774 https://hal.science/hal-03705774/document https://hal.science/hal-03705774/file/Prend_etal-submitted3.pdf doi:10.1029/2022GB007329 IRD: fdi:010085334 WOS: 000819245500001 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2022GB007329 |
container_title |
Global Biogeochemical Cycles |
container_volume |
36 |
container_issue |
7 |
_version_ |
1799468933424611328 |
spelling |
ftanrparis:oai:HAL:hal-03705774v1 2024-05-19T07:31:05+00:00 Sub-seasonal forcing drives year-to-year variations of Southern Ocean primary productivity Prend, Channing J. Keerthi, Madhavan Girijakumari Lévy, Marina Aumont, Olivier Gille, Sarah T. Talley, Lynne D. The Scripps Research Institute La Jolla, San Diego Processus et interactions de fine échelle océanique (PROTEO) Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN) Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) École normale supérieure - Paris (ENS-PSL) Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL) Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) ANR-16-CE01-0014,SOBUMS,Comprendre la réponse du cycle du carbone dans l'océan austral au stress climatique(2016) 2022-07-22 https://hal.science/hal-03705774 https://hal.science/hal-03705774/document https://hal.science/hal-03705774/file/Prend_etal-submitted3.pdf https://doi.org/10.1029/2022GB007329 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2022GB007329 hal-03705774 https://hal.science/hal-03705774 https://hal.science/hal-03705774/document https://hal.science/hal-03705774/file/Prend_etal-submitted3.pdf doi:10.1029/2022GB007329 IRD: fdi:010085334 WOS: 000819245500001 info:eu-repo/semantics/OpenAccess ISSN: 0886-6236 EISSN: 1944-8224 Global Biogeochemical Cycles https://hal.science/hal-03705774 Global Biogeochemical Cycles, 2022, 36 (7), pp.e2022GB007329. ⟨10.1029/2022GB007329⟩ [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 2022 ftanrparis https://doi.org/10.1029/2022GB007329 2024-04-23T03:07:44Z International audience Primary productivity in the Southern Ocean plays a key role in global biogeochemical cycles. While much focus has been placed on phytoplankton production seasonality, non-seasonal fluctuations exceed the amplitude of the seasonal cycle across large swaths of the Antarctic Circumpolar Current. This non-seasonal variability comprises a broad range of timescales from sub-seasonal (<3 months) to multi-annual (>1 year), all of which can project onto the annual mean value. However, year-to-year variations of surface chlorophyll (SChl), a proxy for phytoplankton biomass, are typically attributed to ocean circulation changes associated with the Southern Annular Mode (SAM), which implicitly assumes that sub-seasonal variability averages to near-zero over long timescales. Here, we test this assumption by applying a timeseries decomposition method to satellite-derived SChl in order to separate the low-frequency and high-frequency contributions to the non-seasonal variability. We find that throughout most of the Southern Ocean, year-to-year SChl variations are dominated by the sub-seasonal component, which is not strongly correlated with the SAM. The multi-annual component, while correlated with the SAM, only accounts for about 10% of the total SChl variance. This suggests that changes in annual mean SChl are related to intermittent forcing at small scales, rather than low-frequency climate variability, and thus do not remain correlated over large regions. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean Portail HAL-ANR (Agence Nationale de la Recherche) Global Biogeochemical Cycles 36 7 |