Influence of the North Atlantic subpolar gyre circulation on the 4.2 ka BP event

International audience The 4.2 ka BP event, spanning from ca 4200 to 3900 cal BP, has been documented in numerous archaeological data and continental archives across the Northern Hemisphere as an abrupt shift to dry and cold climate. However, data on synchronous ocean circulation changes are notably...

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Bibliographic Details
Published in:Climate of the Past
Main Authors: Jalali, Bassem, Sicre, Marie-Alexandrine, Azuara, Julien, Pellichero, Violaine, Combourieu-Nebout, Nathalie
Other Authors: 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), Variabilité de l'Océan et de la Glace de mer (VOG), 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)), Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS)
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2019
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Online Access:https://insu.hal.science/insu-02104905
https://insu.hal.science/insu-02104905/document
https://insu.hal.science/insu-02104905/file/Jalali%20et%20al.%20CP2019.pdf
https://doi.org/10.5194/cp-15-701-2019
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Summary:International audience The 4.2 ka BP event, spanning from ca 4200 to 3900 cal BP, has been documented in numerous archaeological data and continental archives across the Northern Hemisphere as an abrupt shift to dry and cold climate. However, data on synchronous ocean circulation changes are notably lacking, thus preventing us from getting a full insight into the physical mechanisms responsible for this climate deterioration. Here, we present two high-resolution (5-20 years) sea surface temperature (SST) records from the subpolar gyre and off north Iceland in the vicinity of the polar front obtained from alkenone paleo-thermometry and compare them with proxy data from the western Mediterranean Sea to gain information on regional temperature and precipitation patterns. Our results are evidence of a temperature dipole pattern which, combined with other paleo-oceanographic records of the North Atlantic, suggests a weakening of the subpolar gyre possibly associated with atmospheric blocked regimes.