气候变化领域集成服务门户(CCPortal): South Asian monsoon response to weakening of Atlantic meridional overturning circulation in a warming climate

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DOI	10.1007/s00382-020-05180-y
	South Asian monsoon response to weakening of Atlantic meridional overturning circulation in a warming climate
	Sandeep N.; Swapna P.; Krishnan R.; Farneti R.; Prajeesh A.G.; Ayantika D.C.; Manmeet S.
发表日期	2020
ISSN	0930-7575
起始页码	3507
结束页码	3524
卷号	54
英文摘要	Observational records and climate model projections reveal a considerable decline in the Atlantic Meridional Overturning Circulation (AMOC). Changes in the AMOC can have a significant impact on the global climate. Sustained warming due to increased greenhouse gas emissions is projected to weaken the AMOC, which in turn can lead to changes in the location of Inter-tropical convergence zone (ITCZ), oceanic and atmospheric large-scale circulation, tropical precipitation and regional monsoons. Using proxy records, observations and CMIP6 simulations of IITM Earth System Model (IITM-ESM), we investigate the changes in the AMOC and associated changes in the large-scale circulation and precipitation patterns over the South Asian monsoon region. Transient CO2 simulation and additional model sensitivity experiments with realistic surface heat and freshwater perturbation anomalies under the experimental protocol of Flux Anomaly Forcing Model Intercomparison Project (FAFMIP) performed with IITM-ESM reveal a decline in the strength of AMOC. The weakening of AMOC is associated with enhanced heat and freshwater forcing in the North Atlantic resulting in the reduction of northward oceanic heat transport and an enhanced northward atmospheric heat transport. Changes in AMOC lead to weakening of large-scale north–south temperature gradient and regional land-sea thermal gradient, which in turn weaken the regional Hadley circulation and, monsoon circulation over the South Asian region. Both the FAFMIP and transient CO2 experiments reveal consistent results of weakening South Asian Monsoon circulation with a decline of AMOC, while precipitation exhibits contrasting responses as precipitation changes are dominated by the thermodynamic response. The suite of observational and numerical analysis provides a mechanistic hypothesis for the weakening of South Asian monsoon circulation concomitant with a weakening of AMOC in a warming climate. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Atlantic meridional overturning circulation; Global warming; Heat transport; South Asian monsoon; Weakening of circulation
语种	英语
scopus关键词	carbon dioxide; climate modeling; CMIP; global climate; greenhouse gas; Hadley cell; heat flow; intertropical convergence zone; meridional circulation; monsoon; overturn; precipitation (climatology); regional climate; Atlantic Ocean; Atlantic Ocean (North); South Asia
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/145528
作者单位	Centre for Climate Change Research, Indian Institute of Tropical Meteorology, Pune, 411008, India; Department of Atmospheric and Space Sciences, Savitribai Phule Pune University, Pune, India; Earth System Physics Section, International Centre for Theoretical Physics, Trieste, Italy
推荐引用方式 GB/T 7714	Sandeep N.,Swapna P.,Krishnan R.,et al. South Asian monsoon response to weakening of Atlantic meridional overturning circulation in a warming climate[J],2020,54.
APA	Sandeep N..,Swapna P..,Krishnan R..,Farneti R..,Prajeesh A.G..,...&Manmeet S..(2020).South Asian monsoon response to weakening of Atlantic meridional overturning circulation in a warming climate.Climate Dynamics,54.
MLA	Sandeep N.,et al."South Asian monsoon response to weakening of Atlantic meridional overturning circulation in a warming climate".Climate Dynamics 54(2020).