气候变化领域集成服务门户(CCPortal): The modulation of Indian summer monsoon onset processes during ENSO through equatorward migration of the subtropical jet stream

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DOI	10.1007/s00382-021-05700-4
	The modulation of Indian summer monsoon onset processes during ENSO through equatorward migration of the subtropical jet stream
	Choudhury D.; Nath D.; Chen W.
发表日期	2021
ISSN	0930-7575
起始页码	2153
结束页码	2172
英文摘要	In this study, we demonstrate a new mechanism, on how the warm phase of El Niño and Southern Oscillation (ENSO) delays the Indian Summer Monsoon onset through coupled ocean-atmospheric processes. Strong basin-wide warming is prominent over North Indian Ocean (NIO) during the El Niño years. The warming is intense over the South West Indian Ocean (SWIO) due to the westward propagation of the equatorial Rossby waves from the Pacific Ocean. It increases the convective activities over the southern tropical Indian Ocean (0–10° S), adjacent to the SWIO region. The warming over the SWIO and the NIO strengthens the divergent wind from the Indian Ocean to the sub-tropics via a wind-evaporation-SST feedback mechanism, which causes more upper-level convergence within 30° N latitudes. Besides, a warmer Indian Ocean enhances the upper-level diabatic heating over the southern Arabian Peninsula and Eastern Indian landmass. These factors strengthen but shift the local Hadley circulation over the Indian Ocean more southward, with an ascending branch centered over the SWIO region. The shifting of the local Hadley circulation during the El Niño years causes the Sub Tropical Jet (STJ) to migrate more southward and centered more over the Indian subcontinent. This southward movement of the STJ over the Indian subcontinent in response to the El Niño condition inhibits the establishment and propagation of the tropical easterly jet during the monsoon season, which subsequently hinders the monsoon circulation, thus delays its onset. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
英文关键词	ENSO; Hadley circulation; Indian summer monsoon onset; Subtropical westerly jet; Tropical easterly jet
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/183547
作者单位	Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China; College of Earth and Planetary Science, University of Chinese Academy of Science, Beijing, China; School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai, China; Guandong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Zhuhai, China
推荐引用方式 GB/T 7714	Choudhury D.,Nath D.,Chen W.. The modulation of Indian summer monsoon onset processes during ENSO through equatorward migration of the subtropical jet stream[J],2021.
APA	Choudhury D.,Nath D.,&Chen W..(2021).The modulation of Indian summer monsoon onset processes during ENSO through equatorward migration of the subtropical jet stream.Climate Dynamics.
MLA	Choudhury D.,et al."The modulation of Indian summer monsoon onset processes during ENSO through equatorward migration of the subtropical jet stream".Climate Dynamics (2021).