气象2025，Vol.51Issue(5)：618-627,10.DOI:10.7519/j.issn.1000-0526.2024.121701
La Niña事件海温异常对2022年9月北太平洋热带气旋活动异常的影响
The Impact of La Niña Related Sea Surface Temperature Anomalies on the Abnormal Activities of Tropical Cyclones over the North Pacific in September 2022
摘要
Abstract
The three consecutive La Niña events that occurred from 2020 to 2023 have been widespread con-cerned,and they also led to various global weather and climate anomalies.By statistically analyzing the tropical cyclone datasets from the National Meteorological Centre of China Meteorological Administration and the National Hurricane Center of the United States,we find that the number of tropical cyclones gen-erated in the North Pacific in September 2022 was far more than the historical average over the same period,with the number of tropical cyclones in the Northeast Pacific reaching a new high in the past 70 years.Based on the reanalysis data and the analysis of the dynamic genesis potential index,it is found that the vertical motion in the middle troposphere made a great contribution to the increased number of tropical cyclones in the North Pacific.Further analysis suggests that during the La Niña events,the temperature of warm pool in the Northwest Pacific continued to rise,convective activity near the Philippines enhanced and the southwesterlies over maritime continent strengthened,which forced the subtropical high over the Northwest Pacific to shift northward.The emergence of low-level cyclonic circulation developing from the anticyclonic circulation in the active tropical cyclone area of the Northwest Pacific enhanced the ascending motion of the middle troposphere,which was favorable for the genesis of tropical cyclones.At the same time,the La Niña events led to continuous increase in the meridional temperature gradient over the North-east Pacific and the meridional Hadley cell got intensified,so the upward movement over the middle and low latitudes strengthened.As the subtropical high located in western Mexico moved eastward,the num-ber of active tropical cyclones in the Northeast Pacific increased.关键词
热带气旋/La Niña/北太平洋/大尺度环流Key words
tropical cyclone/La Niña/North Pacific/large-scale circulation分类
大气科学引用本文复制引用
刘达,董林,向纯怡..La Niña事件海温异常对2022年9月北太平洋热带气旋活动异常的影响[J].气象,2025,51(5):618-627,10.基金项目
国家自然科学基金项目(42205068)、国家重点研发计划(2023YFC3107092)、中国气象局气象能力提升联合研究专项(24NLTSZ004)和中国气象局上海台风研究所台风基金项目(TFJJ202407)共同资助 （42205068）
