Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum
International audience Ocean circulation plays a central role on climate regulation. The paleoceanographic studies of the last decades have allowed to better document the variations in the production of the North Atlantic Deep Water (NADW). However, the role of intermediate water (IW) masses through...
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HAL CCSD
2022
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Online Access: | https://insu.hal.science/insu-03938191 https://doi.org/10.5194/egusphere-egu22-11399 |
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Aix-Marseille Université: HAL |
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English |
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[SDU]Sciences of the Universe [physics] |
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[SDU]Sciences of the Universe [physics] Pourtout, Solène Sépulcre, Sophie Licari, Laetitia Colin, Christophe Michel, Elisabeth Siani, Giuseppe Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
topic_facet |
[SDU]Sciences of the Universe [physics] |
description |
International audience Ocean circulation plays a central role on climate regulation. The paleoceanographic studies of the last decades have allowed to better document the variations in the production of the North Atlantic Deep Water (NADW). However, the role of intermediate water (IW) masses through time remains to be documented and is highly controversial. Indeed, some studies have highlighted the increased contribution of the Antarctic Intermediate Water (AAIW) in all ocean basins during the cold events recorded in the North Atlantic [1] while others suggest their absence [2]. Moreover, during the last deglaciation, the Southern Ocean played a fundamental role in the Carbon transfer from the deep ocean to the atmosphere via the increased upwelling associated to the AAIW production. In order to reconstruct the dynamics of IW masses, to better understand the relationships between variations in ocean circulation in the Atlantic and in the Southern Ocean, and the impact of these changes on the global carbon cycle during Termination I, we use two marine sediment cores from the Porcupine basin MD01-2461 (1153m) and the Iberian margin SU92-28 (997m). We combine the study of benthic foraminifera assemblages sensitive to variations in their environment (nutrient content, oxygen), and different geochemical proxies such as elemental ratios (Mg/Ca, Sr/Ca, Cd/Ca, Ba/Ca, B/Ca, Li/Ca and U/Ca), stable isotopes (δ18O and δ13C) and Neodymium isotopes records (eNd). On core SU92-28, past changes in the benthic foraminiferal content exhibit strong differences in the paleo-environments, with different ecological conditions from the LGM to the Holocene, as well as during the YD and H1 events. These differences are also observed in the δ13C, oxygen concentrations and elemental ratios records obtained from Uvigerina peregrina (or U.mediterranea), Cibicidoides mundulus and Melonis affinis. Changes in the Nd record allow to distinguish changes in the IW mass sources, reflecting the balance between Northern and Southern ... |
author2 |
Géosciences Paris Saclay (GEOPS) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) |
format |
Conference Object |
author |
Pourtout, Solène Sépulcre, Sophie Licari, Laetitia Colin, Christophe Michel, Elisabeth Siani, Giuseppe |
author_facet |
Pourtout, Solène Sépulcre, Sophie Licari, Laetitia Colin, Christophe Michel, Elisabeth Siani, Giuseppe |
author_sort |
Pourtout, Solène |
title |
Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
title_short |
Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
title_full |
Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
title_fullStr |
Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
title_full_unstemmed |
Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
title_sort |
past changes in atlantic ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum |
publisher |
HAL CCSD |
publishDate |
2022 |
url |
https://insu.hal.science/insu-03938191 https://doi.org/10.5194/egusphere-egu22-11399 |
op_coverage |
Vienne (AUT), Unknown Region |
genre |
Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic Southern Ocean |
genre_facet |
Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic Southern Ocean |
op_source |
EGU General Assembly 2022 https://insu.hal.science/insu-03938191 EGU General Assembly 2022, May 2022, Vienne (AUT), Unknown Region. ⟨10.5194/egusphere-egu22-11399⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/egusphere-egu22-11399 insu-03938191 https://insu.hal.science/insu-03938191 BIBCODE: 2022EGUGA.2411399P doi:10.5194/egusphere-egu22-11399 |
op_doi |
https://doi.org/10.5194/egusphere-egu22-11399 |
_version_ |
1799470721926168576 |
spelling |
ftunivaixmarseil:oai:HAL:insu-03938191v1 2024-05-19T07:32:36+00:00 Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum Pourtout, Solène Sépulcre, Sophie Licari, Laetitia Colin, Christophe Michel, Elisabeth Siani, Giuseppe Géosciences Paris Saclay (GEOPS) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Vienne (AUT), Unknown Region 2022-05-23 https://insu.hal.science/insu-03938191 https://doi.org/10.5194/egusphere-egu22-11399 en eng HAL CCSD info:eu-repo/semantics/altIdentifier/doi/10.5194/egusphere-egu22-11399 insu-03938191 https://insu.hal.science/insu-03938191 BIBCODE: 2022EGUGA.2411399P doi:10.5194/egusphere-egu22-11399 EGU General Assembly 2022 https://insu.hal.science/insu-03938191 EGU General Assembly 2022, May 2022, Vienne (AUT), Unknown Region. ⟨10.5194/egusphere-egu22-11399⟩ [SDU]Sciences of the Universe [physics] info:eu-repo/semantics/conferenceObject Conference papers 2022 ftunivaixmarseil https://doi.org/10.5194/egusphere-egu22-11399 2024-05-02T00:02:47Z International audience Ocean circulation plays a central role on climate regulation. The paleoceanographic studies of the last decades have allowed to better document the variations in the production of the North Atlantic Deep Water (NADW). However, the role of intermediate water (IW) masses through time remains to be documented and is highly controversial. Indeed, some studies have highlighted the increased contribution of the Antarctic Intermediate Water (AAIW) in all ocean basins during the cold events recorded in the North Atlantic [1] while others suggest their absence [2]. Moreover, during the last deglaciation, the Southern Ocean played a fundamental role in the Carbon transfer from the deep ocean to the atmosphere via the increased upwelling associated to the AAIW production. In order to reconstruct the dynamics of IW masses, to better understand the relationships between variations in ocean circulation in the Atlantic and in the Southern Ocean, and the impact of these changes on the global carbon cycle during Termination I, we use two marine sediment cores from the Porcupine basin MD01-2461 (1153m) and the Iberian margin SU92-28 (997m). We combine the study of benthic foraminifera assemblages sensitive to variations in their environment (nutrient content, oxygen), and different geochemical proxies such as elemental ratios (Mg/Ca, Sr/Ca, Cd/Ca, Ba/Ca, B/Ca, Li/Ca and U/Ca), stable isotopes (δ18O and δ13C) and Neodymium isotopes records (eNd). On core SU92-28, past changes in the benthic foraminiferal content exhibit strong differences in the paleo-environments, with different ecological conditions from the LGM to the Holocene, as well as during the YD and H1 events. These differences are also observed in the δ13C, oxygen concentrations and elemental ratios records obtained from Uvigerina peregrina (or U.mediterranea), Cibicidoides mundulus and Melonis affinis. Changes in the Nd record allow to distinguish changes in the IW mass sources, reflecting the balance between Northern and Southern ... Conference Object Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic Southern Ocean Aix-Marseille Université: HAL |