Response of East Asian Summer Precipitation to Intermediate SST Anomalies while El Niño Decays and Dependence on Type of Events

• Published in: Journal of Climate
• Main Authors: Wen, Na, Li, Laurent, Hao, Yongsheng
• Other Authors: Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDU]Sciences of the Universe [physics]; Pacific; Indian; North Atlantic
• Online Access: https://insu.hal.science/insu-03726890; https://insu.hal.science/insu-03726890/document; https://insu.hal.science/insu-03726890/file/clim-JCLI-D-21-0335.1.pdf; https://doi.org/10.1175/JCLI-D-21-0335.1

International audience Impacts of El Niño on the following summer East Asian precipitation are dependent on its peak-time characteristics. Three types are identified and denoted as eastern Pacific (EP), mixed-type Pacific (MP), and central Pacific (CP) El Niño. For EP, excessive rainfall occurs in the Yangtze River valley, in relation to an anomalous anticyclone over the western tropical Pacific. For MP, a dipolar precipitation with anomalous wet conditions in northern China and dry conditions in east-central China is mainly due to an anomalous cyclone over Northeast Asia and a weak anticyclone over the Sea of Japan. For the case of CP El Niño, wetness along the Yangtze-Huaihe River valley and dryness in Southeast China are ascribed to an anomalous cyclone in Northeast China and a strong anticyclone over the western tropical Pacific. It is also revealed that the precipitation anomalies are fundamentally caused by different intermediate sea surface temperature (SST) anomalies from other basins while El Niño decays in the following summer. In the case of EP El Niño, the joint action from warm SST in the tropical Indian Ocean, the Niño-1.2 region, and the North Atlantic is responsible for the delayed effect of El Niño. For MP, the main delayed effect comes from warm SST in the northeast subtropical Pacific, developing La Niña, and cold SST in the southern tropical Atlantic. Finally, CP El Niño exerts its delayed influence through warm SST in the northern tropical Atlantic.