气候变化领域集成服务门户(CCPortal): Disentangling sea-surface temperature and anthropogenic aerosol influences on recent trends in South Asian monsoon rainfall

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DOI	10.1007/s00382-018-4251-y
	Disentangling sea-surface temperature and anthropogenic aerosol influences on recent trends in South Asian monsoon rainfall
	Patil N.; Venkataraman C.; Muduchuru K.; Ghosh S.; Mondal A.
发表日期	2019
ISSN	0930-7575
起始页码	2287
结束页码	2302
卷号	52 期号:2020-03-04
英文摘要	Recent studies point to combined effects of changes in regional land-use, anthropogenic aerosol forcing and sea surface temperature (SST) gradient on declining trends in the South Asian monsoon (SAM). This study attempted disentangling the effects produced by changes in SST gradient from those by aerosol levels in an atmospheric general circulation model. Two pairs of transient ensemble simulations were made, for a 40-year period from 1971 to 2010, with evolving versus climatological SSTs and with anthropogenic aerosol emissions fixed at 1971 versus 2010, in each case with evolution of the other forcing element, as well as GHGs. Evolving SST was linked to a widespread feedback on increased surface temperature, reduced land–sea thermal contrast and a weakened Hadley circulation, with weakening of cross-equatorial transport of moisture transport towards South Asia. Increases in anthropogenic aerosol levels (1971 versus 2010), led to an intensification of drying in the peninsular Indian region, through several regional pathways. Aerosol forcing induced north–south asymmetries in temperature and sea-level pressure response, and a cyclonic circulation in the Bay of Bengal, leading to an easterly flow, which opposes the monsoon flow, suppressing moisture transport over peninsular India. Further, aerosol induced decreases in convection, vertically integrated moisture flux convergence, evaporation flux and cloud fraction, in the peninsular region, were spatially congruent with reduced convective and stratiform rainfall. Overall, evolution of SST acted through a weakening of cross-equatorial moisture flow, while increases in aerosol levels acted through suppression of Arabian Sea moisture transport, as well as, of convection and vertical moisture transport, to influence the suppression of SAM rainfall. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Aerosol–cloud–rainfall interaction; Anthropogenic aerosols; ECHAM6-HAM; GCM simulations
语种	英语
scopus关键词	aerosol; air-sea interaction; anthropogenic source; atmospheric general circulation model; moisture transfer; monsoon; rainfall; sea surface temperature; temperature gradient; trend analysis; Arabian Sea; India; Indian Ocean
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/146543
作者单位	Interdiciplinary Program in Climate Studies, Indian Institute of Technology Bombay, Powai, Mumbai, 400 076, India; Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, India; Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, India
推荐引用方式 GB/T 7714	Patil N.,Venkataraman C.,Muduchuru K.,et al. Disentangling sea-surface temperature and anthropogenic aerosol influences on recent trends in South Asian monsoon rainfall[J],2019,52(2020-03-04).
APA	Patil N.,Venkataraman C.,Muduchuru K.,Ghosh S.,&Mondal A..(2019).Disentangling sea-surface temperature and anthropogenic aerosol influences on recent trends in South Asian monsoon rainfall.Climate Dynamics,52(2020-03-04).
MLA	Patil N.,et al."Disentangling sea-surface temperature and anthropogenic aerosol influences on recent trends in South Asian monsoon rainfall".Climate Dynamics 52.2020-03-04(2019).