气候变化领域集成服务门户(CCPortal): Synoptic-Scale Circulation Precursors of Extreme Precipitation Events Over Southwest China During the Rainy Season

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DOI	10.1029/2021JD035134
	Synoptic-Scale Circulation Precursors of Extreme Precipitation Events Over Southwest China During the Rainy Season
	Nie Y.; Sun J.
发表日期	2021
ISSN	2169-897X
卷号	126 期号:13
英文摘要	This study analyzes the synoptic-scale circulation patterns favorable for regional extreme precipitation events over southwest China (SWC) from 1979 to 2018 occurring during the rainy seasons. The whole SWC is regionalized into two subregions, western SWC and eastern SWC, according to the spatial distribution of two extreme precipitation indices. Furthermore, the atmospheric patterns associated with the independent regional extreme precipitation events (REPEs) that occurred over the two subregions are categorized into two types using k-means clustering. For type 1, a Rossby wave train originating from the Northeast Atlantic almost a week before REPEs leads to an anomalous low over the eastern Tibetan Plateau (TP), inducing upper-troposphere divergence and ascending motion over SWC. Moreover, anomalous convective activities over India and the Bay of Bengal (the enhanced and westward-extended western Pacific subtropical high) are critical precursors of REPEs over western (eastern) SWC. For type 2, an anomalous high is developed over the Ural Mountains at least a week prior to REPEs. The subsequent anomalous low over Lake Baikal and eastward-shifted South Asian high are conducive to forming updrafts over SWC. An anomalous anticyclone at the middle-to-lower troposphere south of the TP is the main moisture contributor. Discrepancies in the zonal location of the Lake Baikal low and the strength of the Ural Mountain high, as well as the intensity of atmospheric circulation anomalies at low latitudes, are the major differences between the type 2 events occurring in western and eastern SWC. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	atmospheric circulation; extreme precipitation events; k-means clustering; rainy season; southwest China
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/237140
作者单位	Nansen-Zhu International Research Center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China; National Institute of Natural Hazards, Ministry of Emergency Management of China, Beijing, China
推荐引用方式 GB/T 7714	Nie Y.,Sun J.. Synoptic-Scale Circulation Precursors of Extreme Precipitation Events Over Southwest China During the Rainy Season[J],2021,126(13).
APA	Nie Y.,&Sun J..(2021).Synoptic-Scale Circulation Precursors of Extreme Precipitation Events Over Southwest China During the Rainy Season.Journal of Geophysical Research: Atmospheres,126(13).
MLA	Nie Y.,et al."Synoptic-Scale Circulation Precursors of Extreme Precipitation Events Over Southwest China During the Rainy Season".Journal of Geophysical Research: Atmospheres 126.13(2021).