Scopus记录号: 2-s2.0-85046897706
论文题名: Disentangling sea-surface temperature and anthropogenic aerosol influences on recent trends in South Asian monsoon rainfall
作者: Patil N. ; Venkataraman C. ; Muduchuru K. ; Ghosh S. ; Mondal A.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2019
卷: 52, 期: 2019-03-04 起始页码: 2287
结束页码: 2302
语种: 英语
英文关键词: Aerosol–cloud–rainfall interaction
; Anthropogenic aerosols
; ECHAM6-HAM
; GCM simulations
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. 资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/122412
Appears in Collections: 气候变化事实与影响
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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
Recommended Citation:
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]. Climate Dynamics,2019-01-01,52(2019-03-04)