气候变化领域集成服务门户(CCPortal): Significant changes in the ENSO-monsoon relationship and associated circulation features on multidecadal timescale

CCPortal

DOI	10.1007/s00382-019-05071-x
	Significant changes in the ENSO-monsoon relationship and associated circulation features on multidecadal timescale
	Seetha C.J.; Varikoden H.; Babu C.A.; Kuttippurath J.
发表日期	2020
ISSN	0930-7575
起始页码	1491
结束页码	1506
卷号	54
英文摘要	We observe significant changes in the ENSO–Indian summer monsoon rainfall (ISMR) relationship in past three multidecadal epochs (early epoch: 1931–1960, middle epoch: 1961–1990, and recent epoch: 1991–2015) based on consistent correlation. The rainfall during early epoch was above normal, however, in other two epochs it was relatively dry. The ENSO–ISMR relationship and its changes are mostly pronounced in the monsoon core zone. During the early epoch, the effect of La Niña was more dominant by accounting higher number of La Niña events with higher values of Niño 3.4 index, which can be attributed to the surplus rainfall over most regions of India. The rainfall during the consecutive two multidecadal epochs is below normal and this may be attributed to the strong El Niño events. The dryness in the northeast region cannot be linked with ENSO events as it has insignificant relationship with the rainfall over this region. The weakening of Low Level Jet during the recent epoch can be a reason to reduce monsoon rainfall during recent periods. It is evident that the reduced moisture transport also accounts for the reduced precipitation. The changes in equatorial Walker and regional Hadley circulations during the three epochs show the same mode of variability and in phase with the changes in rainfall and other circulation related parameters. This study emphasizes the basin mode warming of world oceans and the increased frequency of El Nino events during the recent epochs linked to the climate change and its impact of ISMR. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Circulation; ENSO; ISMR; Moisture flux; Multidecadal variability
语种	英语
scopus关键词	climate change; El Nino-Southern Oscillation; Hadley cell; moisture flux; monsoon; rainfall; timescale; Walker circulation; India
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/145643
作者单位	Department of Atmospheric Sciences, Cochin University of Sciences and Technology, Kochi, 682016, India; Indian Institute of Tropical Meteorology, Pashan, Pune, 411008, India; CORAL, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
推荐引用方式 GB/T 7714	Seetha C.J.,Varikoden H.,Babu C.A.,et al. Significant changes in the ENSO-monsoon relationship and associated circulation features on multidecadal timescale[J],2020,54.
APA	Seetha C.J.,Varikoden H.,Babu C.A.,&Kuttippurath J..(2020).Significant changes in the ENSO-monsoon relationship and associated circulation features on multidecadal timescale.Climate Dynamics,54.
MLA	Seetha C.J.,et al."Significant changes in the ENSO-monsoon relationship and associated circulation features on multidecadal timescale".Climate Dynamics 54(2020).