气候变化领域集成服务门户(CCPortal): Subseasonal intensity variation of the South Asian high in relationship to diabatic heating: observation and CMIP5 models

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DOI	10.1007/s00382-018-4266-4
	Subseasonal intensity variation of the South Asian high in relationship to diabatic heating: observation and CMIP5 models
	Shang W.; Ren X.; Huang B.; Cubasch U.; Yang X.-Q.
发表日期	2019
ISSN	0930-7575
起始页码	2413
结束页码	2430
卷号	52 期号:2020-03-04
英文摘要	This study investigates the subseasonal intensity variation of South Asian high (SAH) and the dynamic linkage with precipitation induced diabatic heating during the summer of 1979–2005, based on the observation and 18 models from the Coupled Model Intercomparison Project (CMIP5). The SAH’s intensity variation with a period of approximately 10–36 days is identified both in the observation and 18 models, by performing an empirical orthogonal function (EOF) analysis on the standardized subseasonal anomalies in geopotential height at 100 hPa over the SAH’s main body region. With the observed strengthening of the SAH, an enhanced rainfall belt between 70°–120°E migrates northward from the equatorial region. The northward propagating rainfall belt occupies almost the whole Indian subcontinent, Indochina Peninsula and subtropical east Asian regions between 20°–40°N when the SAH reaches the strongest. The relative vorticity diagnosis reveals the dynamical linkage between the subseasonal SAH’s intensity variation and the precipitation anomalies over the Asian monsoon region: (1) The observed northward propagating rainfall band forms a horizontal gradient of diabatic heating, favoring an enhancement of the SAH over its southern part; (2) When the rainfall band approaches the regions of South and East Asia between 20°–40°N, the increased vertical gradient of diabatic heating in the upper level contributes significantly to the intensification of the SAH; (3) The horizontal advection process favors the westward expansion of the SAH. The observation-to-model comparisons indicate that the model’s capacity to reproduce the SAH’s intensity variation is highly associated with simulations of the anomalous rainfall band and its northward propagation. A realistic reproduction of precipitation anomalies is fundamental to simulating the dynamical processes related to diabatic heating, and thus the simulation of the SAH’s subseasonal intensity variation. © 2018, The Author(s).
英文关键词	CMIP5; Diabatic heating; South Asian high; Subseasonal intensity variation
语种	英语
scopus关键词	anticyclone; climate modeling; CMIP; diabatic process; heating; monsoon; precipitation (climatology); rainband; rainfall; seasonal variation; 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/146521
作者单位	CMA-NJU Joint Laboratory for Climate Prediction Studies, School of Atmospheric Sciences, Nanjing University, Nanjing, 210023, China; Industrial Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim, Norway; Institute of Meteorology, Freie Universität Berlin, Berlin, Germany
推荐引用方式 GB/T 7714	Shang W.,Ren X.,Huang B.,et al. Subseasonal intensity variation of the South Asian high in relationship to diabatic heating: observation and CMIP5 models[J],2019,52(2020-03-04).
APA	Shang W.,Ren X.,Huang B.,Cubasch U.,&Yang X.-Q..(2019).Subseasonal intensity variation of the South Asian high in relationship to diabatic heating: observation and CMIP5 models.Climate Dynamics,52(2020-03-04).
MLA	Shang W.,et al."Subseasonal intensity variation of the South Asian high in relationship to diabatic heating: observation and CMIP5 models".Climate Dynamics 52.2020-03-04(2019).