气候变化领域集成服务门户(CCPortal): Diagnostics of westward propagating East Asian monsoon low-pressure systems that reach the Indian monsoon region

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DOI	10.1007/s00382-019-05041-3
	Diagnostics of westward propagating East Asian monsoon low-pressure systems that reach the Indian monsoon region
	Shi X.; Kiladis G.; Wen M.
发表日期	2020
ISSN	0930-7575
起始页码	987
结束页码	1005
卷号	54 期号:2020-01-02
英文摘要	The East Asian monsoon low-pressure systems (MLPSs) are important rain-producing weather disturbances in East Asia during the summer (June, July and August). After formation, they primarily move westward and impact southern China and the Indochina Peninsula. We analyzed the climate distribution characteristics of generation locations and frequency of different intensity events in westward East Asian MLPSs during the summers of 1979–2012. The East Asian and the Indian MLPSs are relatively independent weather systems and the Indochina Peninsula area separates them. The westward East Asian monsoon low-pressure system (MLPS) rarely moves to the Indian monsoon region (IMR). When an East Asian MLPS crosses the boundary between the East Asian monsoon region (EAMR) and the IMR, the potential vorticity (PV) axis near the low-pressure center remains vertical with height, while the PV axis near the center of the East Asian MLPSs that do not cross the boundary shifts to the northeast with height. The East Asian MLPSs that reach the IMR are stronger before crossing the boundary than the MLPSs that do not cross the boundary. The strength of the MLPS that approach the boundary gradually weakens during the westward movement. The middle and high-level PV center shifts to the northeast of the low-pressure center, which causes the MLPS to turn and fail to cross the boundary between EAMR and IMR. Variation of the PV budget at 500 hPa over time showed that a strong positive PV tendency forms on the north side of low-pressure center mainly due to horizontal adiabatic PV advection. The PV center gradually shifts to the north and the MLPS turns. The PV budget at 500 hPa for the East Asian MLPS that reach the IMR shows that the horizontal and vertical adiabatic advection PV transport has a strong positive tendency on the northwest side of the low-pressure center, causing the MLPS to continue moving northwestward and eventually cross the boundary to reach the IMR. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	East Asian monsoon low pressure system; India monsoon region; Potential vorticity (PV); PV budget
语种	英语
scopus关键词	adiabatic process; advection; atmospheric dynamics; low pressure system; monsoon; potential vorticity; pressure field; Far East; India; Indochina
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/145740
作者单位	State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing, 100081, China; NOAA Earth System Research Laboratory, Boulder, CO, United States; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing, 210044, China
推荐引用方式 GB/T 7714	Shi X.,Kiladis G.,Wen M.. Diagnostics of westward propagating East Asian monsoon low-pressure systems that reach the Indian monsoon region[J],2020,54(2020-01-02).
APA	Shi X.,Kiladis G.,&Wen M..(2020).Diagnostics of westward propagating East Asian monsoon low-pressure systems that reach the Indian monsoon region.Climate Dynamics,54(2020-01-02).
MLA	Shi X.,et al."Diagnostics of westward propagating East Asian monsoon low-pressure systems that reach the Indian monsoon region".Climate Dynamics 54.2020-01-02(2020).