Northeast Pacific warm blobs sustained via extratropical atmospheric teleconnections

• Published in: Nature Communications
• Main Authors: Shi, Jian, Huang, Hao, Fedorov, Alexey, Holbrook, Neil J., Zhang, Yu, Ding, Ruiqiang, Luo, Yongyue, Wang, Shengpeng, Chen, Jiajie, Hu, Xi, Liu, Qinyu, Huang, Fei, Lin, Xiaopei
• Other Authors: Ocean University of China (OUC), Department of Earth and Planetary Sciences New Haven, Yale University New Haven, Océan et variabilité du climat (LOCEAN-VARCLIM), 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), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-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), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-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)), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institute for Marine and Antarctic Studies Hobart (IMAS), University of Tasmania Hobart (UTAS), State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University (BNU), Laoshan Laboratory
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2024
• Subjects: [SDU]Sciences of the Universe [physics]; Pacific; North Atlantic
• Online Access: https://insu.hal.science/insu-04725893; https://insu.hal.science/insu-04725893v1/document; https://insu.hal.science/insu-04725893v1/file/s41467-024-47032-x.pdf; https://doi.org/10.1038/s41467-024-47032-x

International audience Large-scale marine heatwaves in the Northeast Pacific (NEP), identified here and previously as `warm blobs', have devastating impacts on regional ecosystems. An anomalous atmospheric ridge over the NEP is known to be crucial for maintaining these warm blobs, also causing abnormally cold temperatures over North America during the cold season. Previous studies linked this ridge to teleconnections from tropical sea surface temperature anomalies. However, it was unclear whether teleconnections from the extratropics could also contribute to the ridge. Here we show that planetary wave trains, triggered by increased rainfall and latent heat release over the Mediterranean Sea accompanied by decreased rainfall over the North Atlantic, can transport wave energy to the NEP, guided by the westerly jet, and induce a quasi-barotropic ridge there. Our findings provide insights into extratropical teleconnections sustaining the NEP ridge, offering a source of potential predictability for the warm blobs and temperature fluctuations over North America.