Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations
International audience Both deepwater formation and the obduction processes converting dense deepwater to lighter surface water are the engine for the global meridional overturning circulation (MOC). Their spatio‐temporal variations effectively modify the ocean circulation and related carbon cycle,...
Published in: | Paleoceanography and Paleoclimatology |
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Online Access: | https://hal.science/hal-03079059 https://hal.science/hal-03079059/document https://hal.science/hal-03079059/file/870257_2_merged_1602519769_small.pdf https://doi.org/10.1029/2019PA003845 |
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ftanrparis:oai:HAL:hal-03079059v1 2023-12-17T10:22:06+01:00 Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations Zhang, Yurui Grima, Nicolas Huck, Thierry 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) Interdisciplinary Graduate School for the Blue planet ANR-17-EURE-0015,ISBlue,Interdisciplinary Graduate School for the Blue planet(2017) 2021 https://hal.science/hal-03079059 https://hal.science/hal-03079059/document https://hal.science/hal-03079059/file/870257_2_merged_1602519769_small.pdf https://doi.org/10.1029/2019PA003845 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2019PA003845 hal-03079059 https://hal.science/hal-03079059 https://hal.science/hal-03079059/document https://hal.science/hal-03079059/file/870257_2_merged_1602519769_small.pdf doi:10.1029/2019PA003845 info:eu-repo/semantics/OpenAccess ISSN: 2572-4525 EISSN: 1944-9186 Paleoceanography and Paleoclimatology https://hal.science/hal-03079059 Paleoceanography and Paleoclimatology, 2021, 36 (1), pp.e2019PA003845. ⟨10.1029/2019PA003845⟩ [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDE.MCG]Environmental Sciences/Global Changes info:eu-repo/semantics/article Journal articles 2021 ftanrparis https://doi.org/10.1029/2019PA003845 2023-11-18T22:34:03Z International audience Both deepwater formation and the obduction processes converting dense deepwater to lighter surface water are the engine for the global meridional overturning circulation (MOC). Their spatio‐temporal variations effectively modify the ocean circulation and related carbon cycle, which affects climate evolution throughout geological time. Using early‐Eocene bathymetry and enhanced atmospheric CO2 concentration, the IPSL‐CM5A2 climate model has simulated a well‐ventilated Southern Ocean associated with a strong anticlockwise MOC.To trace the fates of these paleo Antarctic Bottom Water (paleo‐AABW), we conducted Lagrangian analyses using these IPSL‐CM5A2 model results and tracking virtual particles released at the lower limb of the MOC, defined as an initial section at 60°S below 1900m depth. Diagnostic analysis of these particles trajectories reveals that most paleo‐AABW circulates back to the Southern Ocean through either the initial section (43%) or the section above (31%); the remaining (>25%) crossing the base of the mixed layer mostly in tropical regions (up to half). The majority of water parcels ending in the mixed layer experience negative density transformations, intensified in the upper 500m and mostly occurring in tropical upwelling regions, with a spatial pattern consistent with the wind‐driven Ekman pumping, largely determined by the Eocene wind stress and continental geometry.In the same way as present‐day North Atlantic Deep Water upwells in the Southern Ocean, our results suggest that the strong tropical and equatorial upwelling during the Eocene provides an efficient pathway from the abyss to the surface, but at much higher temperature, with potential implications for the oceanic carbon cycle. Article in Journal/Newspaper Antarc* Antarctic North Atlantic Deep Water North Atlantic Southern Ocean Portail HAL-ANR (Agence Nationale de la Recherche) Antarctic Southern Ocean Paleoceanography and Paleoclimatology 36 1 |
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Open Polar |
collection |
Portail HAL-ANR (Agence Nationale de la Recherche) |
op_collection_id |
ftanrparis |
language |
English |
topic |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDE.MCG]Environmental Sciences/Global Changes |
spellingShingle |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDE.MCG]Environmental Sciences/Global Changes Zhang, Yurui Grima, Nicolas Huck, Thierry Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations |
topic_facet |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDE.MCG]Environmental Sciences/Global Changes |
description |
International audience Both deepwater formation and the obduction processes converting dense deepwater to lighter surface water are the engine for the global meridional overturning circulation (MOC). Their spatio‐temporal variations effectively modify the ocean circulation and related carbon cycle, which affects climate evolution throughout geological time. Using early‐Eocene bathymetry and enhanced atmospheric CO2 concentration, the IPSL‐CM5A2 climate model has simulated a well‐ventilated Southern Ocean associated with a strong anticlockwise MOC.To trace the fates of these paleo Antarctic Bottom Water (paleo‐AABW), we conducted Lagrangian analyses using these IPSL‐CM5A2 model results and tracking virtual particles released at the lower limb of the MOC, defined as an initial section at 60°S below 1900m depth. Diagnostic analysis of these particles trajectories reveals that most paleo‐AABW circulates back to the Southern Ocean through either the initial section (43%) or the section above (31%); the remaining (>25%) crossing the base of the mixed layer mostly in tropical regions (up to half). The majority of water parcels ending in the mixed layer experience negative density transformations, intensified in the upper 500m and mostly occurring in tropical upwelling regions, with a spatial pattern consistent with the wind‐driven Ekman pumping, largely determined by the Eocene wind stress and continental geometry.In the same way as present‐day North Atlantic Deep Water upwells in the Southern Ocean, our results suggest that the strong tropical and equatorial upwelling during the Eocene provides an efficient pathway from the abyss to the surface, but at much higher temperature, with potential implications for the oceanic carbon cycle. |
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) Interdisciplinary Graduate School for the Blue planet ANR-17-EURE-0015,ISBlue,Interdisciplinary Graduate School for the Blue planet(2017) |
format |
Article in Journal/Newspaper |
author |
Zhang, Yurui Grima, Nicolas Huck, Thierry |
author_facet |
Zhang, Yurui Grima, Nicolas Huck, Thierry |
author_sort |
Zhang, Yurui |
title |
Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations |
title_short |
Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations |
title_full |
Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations |
title_fullStr |
Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations |
title_full_unstemmed |
Fates of paleo Antarctic Bottom Water during the early Eocene ― based on a Lagrangian analysis of IPSL‐CM5A2 climate model simulations |
title_sort |
fates of paleo antarctic bottom water during the early eocene ― based on a lagrangian analysis of ipsl‐cm5a2 climate model simulations |
publisher |
HAL CCSD |
publishDate |
2021 |
url |
https://hal.science/hal-03079059 https://hal.science/hal-03079059/document https://hal.science/hal-03079059/file/870257_2_merged_1602519769_small.pdf https://doi.org/10.1029/2019PA003845 |
geographic |
Antarctic Southern Ocean |
geographic_facet |
Antarctic Southern Ocean |
genre |
Antarc* Antarctic North Atlantic Deep Water North Atlantic Southern Ocean |
genre_facet |
Antarc* Antarctic North Atlantic Deep Water North Atlantic Southern Ocean |
op_source |
ISSN: 2572-4525 EISSN: 1944-9186 Paleoceanography and Paleoclimatology https://hal.science/hal-03079059 Paleoceanography and Paleoclimatology, 2021, 36 (1), pp.e2019PA003845. ⟨10.1029/2019PA003845⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2019PA003845 hal-03079059 https://hal.science/hal-03079059 https://hal.science/hal-03079059/document https://hal.science/hal-03079059/file/870257_2_merged_1602519769_small.pdf doi:10.1029/2019PA003845 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2019PA003845 |
container_title |
Paleoceanography and Paleoclimatology |
container_volume |
36 |
container_issue |
1 |
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1785543185255104512 |