气候变化领域集成服务门户(CCPortal): Impact of potential vorticity anomalies around the eastern Tibetan Plateau on quasi-biweekly oscillations of summer rainfall within and south of the Yangtze Basin in 2016

CCPortal

DOI	10.1007/s00382-020-05505-x
	Impact of potential vorticity anomalies around the eastern Tibetan Plateau on quasi-biweekly oscillations of summer rainfall within and south of the Yangtze Basin in 2016
	Zhang G.; Mao J.; Wu G.; Liu Y.
发表日期	2020
ISSN	0930-7575
英文摘要	Six persistent heavy rainfall events that occurred mostly over Hubei–Anhui–Jiangxi (HAJ) provinces within and south of the middle–lower Yangtze Basin during the summer of 2016 were regulated by the 10–20-day quasi-biweekly oscillation (QBWO). The characteristics and mechanisms of the QBWO associated with the HAJ rainfall events were examined using ERA-Interim reanalysis data. Composite analysis shows that during a QBWO cycle, the extreme wet (dry) phase of the HAJ rainfall was characterized by the strongest ascending (descending) motion associated with an anomalous upper-tropospheric saddle-shaped circulation field resulting from an eastward-propagating middle–high latitude wave train and westward-migrating tropical potential vorticity (PV) anomalies. The wet (dry) phase was preceded by the corridor establishment of significant anomalous poleward-directed (equatorward-directed) moisture transport over southern China on the northwestern side of the western North Pacific subtropical high in the lower troposphere. The corridor-related moisture convergence (divergence) over the HAJ tended to intensify as an anomalous anticyclone (cyclone) propagated northwestward to the northern South China Sea, in conjunction with the eastward-propagating mid-latitude wave train. The QBWO of the HAJ rainfall was closely linked with upstream PV anomalies generated over the eastern slope of the Tibetan Plateau (TP) due to topographic lateral friction. The PV budget analysis demonstrates that the horizontal PV advection and subsequent topographic friction with a four-day phase-lag between them dictated the QBWO of PV anomalies around the eastern TP. The TP-generated PV anomalies then migrate downstream to facilitate the development of the anomalous circulation over the HAJ. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Potential vorticity; Quasi-biweekly oscillation; Summer yangtze rainfall; Tibetan Plateau; Topographic friction
语种	英语
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/145669
作者单位	State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences, P.O. Box 9804, Beijing, 100029, China; University of Chinese Academy of Sciences, Beijing, 100049, China
推荐引用方式 GB/T 7714	Zhang G.,Mao J.,Wu G.,et al. Impact of potential vorticity anomalies around the eastern Tibetan Plateau on quasi-biweekly oscillations of summer rainfall within and south of the Yangtze Basin in 2016[J],2020.
APA	Zhang G.,Mao J.,Wu G.,&Liu Y..(2020).Impact of potential vorticity anomalies around the eastern Tibetan Plateau on quasi-biweekly oscillations of summer rainfall within and south of the Yangtze Basin in 2016.Climate Dynamics.
MLA	Zhang G.,et al."Impact of potential vorticity anomalies around the eastern Tibetan Plateau on quasi-biweekly oscillations of summer rainfall within and south of the Yangtze Basin in 2016".Climate Dynamics (2020).