气候变化领域集成服务门户(CCPortal): Differences between decadal decreases of boreal summer rainfall in southeastern and southwestern China in the early 2000s

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DOI	10.1007/s00382-018-4408-8
	Differences between decadal decreases of boreal summer rainfall in southeastern and southwestern China in the early 2000s
	Ha Y.; Zhong Z.; Hu Y.; Zhu Y.; Zang Z.; Zhang Y.; Yao Y.; Sun Y.
发表日期	2019
ISSN	0930-7575
起始页码	3533
结束页码	3552
卷号	52 期号:2020-05-06
英文摘要	On decadal time scale, the boreal summer (June–August) rainfall over southern China significantly decreased during the epoch 2003–2012 compared to that in the preceding epoch 1993–2002. This study investigates different processes involved in the decadal decreases in summer rainfall over southeastern China (SEC) and southwestern China (SWC) since the early 2000s. Possible mechanisms for these changes are also explored. Results show that the daily total amount of rainfall in light, moderate and heavy (light and moderate) grades during 2003–2012 is significantly lower than that in the preceding period 1993–2002 by 14.4% (8.2%) over SEC (SWC) region. The epochal rainfall change caused by changes in the light, moderate and heavy (light and moderate) grades accounts for 90% (86%) of total summer rainfall difference between the epoch 1993–2002 and 2003–2012 over SEC (SWC). Based on regression and composite analyses, it is found that the reasons for decadal changes in summer rainfall in the early 2000s are different for the two regions. The rainfall decrease over SEC is attribute to reduced moisture transport by the southwesterly flow from the South China Sea, which is caused by the northward-shift of the western Pacific subtropical high (WPSH) in association with the sea surface temperature (SST) cooling over the western North Pacific (WNP) to the east of Japan. The rainfall decrease over SWC can be explained by reduced moisture transported by the southwesterly/westerly from the Bay of Bengal, which induced by the weakened South Asian monsoon since the early 2000s that is plausibly related to SST warming over the northern Indian Ocean (NIO). Furthermore, the anomalous anticyclonic circulations connected to the NIO warming and WNP cooling make a southwest-northeast-oriented high pressure band. WPSH shifts northward, extending from east of Japan to the Bay of Bengal. SEC and SWC are located along the southern flank of the “dumbbell-shaped” subtropical high band, where the northeasterly prevails. As a result, moisture transports from the South China Sea and the Bay of Bengal to SEC and SWC both decrease on the decadal time scale since 2003. Although different physical-dynamical processes are involved in rainfall changes over the two different regions, the summer rainfall decreases on the decadal time scale are closely related to the shifts in SSTA pattern and background atmospheric circulation on global-scale that occurred in the early 2000s. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Early 2000s; Interdecadal/decadal change; North Indian Ocean; Northward-shifting Western Pacific tropical high; Southeast China; Southwest China; Summer rainfall; Western North Pacific
语种	英语
scopus关键词	atmospheric circulation; decadal variation; moisture transfer; precipitation intensity; regression analysis; sea surface temperature; summer; warming; westerly; China; Indian Ocean; Indian Ocean (North); Pacific Ocean; Pacific Ocean (North); Pacific Ocean (West)
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146439
作者单位	College of Meteorology and Oceanography, National University of Defense Technology, No. 60, Shuanglong Road, Nanjing, 211101, China; Key Laboratory of Meteorological Disaster of Ministry of Education, and Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Sciences and Technology, Nanjing, China; Jiangsu Collaborative Innovation Center for Climate Change and School of Atmospheric Sciences, Nanjing University, Nanjing, China
推荐引用方式 GB/T 7714	Ha Y.,Zhong Z.,Hu Y.,et al. Differences between decadal decreases of boreal summer rainfall in southeastern and southwestern China in the early 2000s[J],2019,52(2020-05-06).
APA	Ha Y..,Zhong Z..,Hu Y..,Zhu Y..,Zang Z..,...&Sun Y..(2019).Differences between decadal decreases of boreal summer rainfall in southeastern and southwestern China in the early 2000s.Climate Dynamics,52(2020-05-06).
MLA	Ha Y.,et al."Differences between decadal decreases of boreal summer rainfall in southeastern and southwestern China in the early 2000s".Climate Dynamics 52.2020-05-06(2019).