Compound hot drought events in the Mei-yu region:influences from polar and tropical regions  

梅雨区复合高温干旱事件:极地和热带的影响

作　　者：Huixin Li Bo Sun Zhongshi Zhang Huijun Wang Yeran Zhou Jiani Zeng Botao Zhou 李惠心;孙博;张仲石;王会军;周烨然;曾佳妮;周波涛

机构地区：[1]Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disasters,Ministry of Education/Joint International Research Laboratory of Climate and Environment Change,Nanjing University of Information Science and Technology,Nanjing 210044,China [2]Southern Marine Science and Engineering Guangdong Laboratory,Zhuhai 519000,China [3]Nansen-Zhu International Research Centre,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China [4]Department of Atmospheric Science,School of Environmental Studies,China University of Geosciences,Wuhan 430074,China [5]School of Geographic Science,Nantong University,Nantong 226019,China

出　　处：《Science Bulletin》2025年第2期273-282,共10页科学通报(英文版)

基　　金：supported by the National Natural Science Foundation of China(42088101);the National Key Research and Development Program of China(2022YFF0801704);the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(316323005)。

摘　　要：In the Mei-yu region,there has been noticeable increase in the occurrence of compound hot drought(CHD)events in recent years.However,the underlying causes of these occurrences remain poorly understood.To address this knowledge gap,we conducted a comprehensive study utilizing observational datasets,reanalysis datasets,and four numerical experiments to investigate the associated physical mechanisms.Our findings indicated that the prevalence of CHD events in the Mei-yu region is influenced strongly by two key factors:the decline in Barents Sea ice during February and the presence of a La Ni?alike pattern of sea surface temperature(SST)in April.The decline in Barents Sea ice generates an anomalous Rossby wave in the Arctic that propagates southeastward.The La Ni?a-like SST pattern regulates a Rossby wave over western America,propagating along the subtropical jet stream.These two Rossby waves induce northward movement and strengthened intensity of the subtropical westerly jet in East Asia.The local circulation patterns in the Mei-yu region are influenced by the position and intensity of the subtropical jet,leading to downward motion in accordance with the secondary circulation theory for high-altitude jet streams.Consequently,these local circulation patterns might contribute to occurrence of CHD events.Moreover,our analysis revealed that the impact of Barents Sea ice and the La Nina-like SST pattern can explain approximately two-thirds of the mild CHD events in the Mei-yu region,and that the influence of each is relatively independent.This research underscores influences of polartropical systems on climate extremes in eastern Asia.

关 键 词：Compound hot drought events Mei-yu region June-July Barents Sea ice La Niña-like SST Respective and combined influences 

分 类 号：R54[医药卫生—心血管疾病]