气候变化领域集成服务门户(CCPortal): Influence of Indian Ocean SST regionality on the East African short rains

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DOI	10.1007/s00382-020-05265-8
	Influence of Indian Ocean SST regionality on the East African short rains
	Liu W.; Cook K.H.; Vizy E.K.
发表日期	2020
ISSN	0930-7575
起始页码	4991
结束页码	5011
卷号	54
英文摘要	Three sub-regions of the Indian Ocean in which SSTs significantly influence the equatorial East African short rains on interannual timescales are identified, and the physical processes of this influence are studied using regional climate model simulations from the Weather Research and Forecasting model (WRF). Five 20-year ensemble integrations are generated to represent a control climate and to simulate the individual and combined effects of SSTAs in the influential regions. SSTAs in the western Indian Ocean exert a stronger influence on the equatorial East African short rains than central and eastern Indian Ocean SSTAs both in terms of the coverage of significantly-changed precipitation and the magnitude of the precipitation response. Positive western Indian Ocean SSTAs significantly increase the short rains over 95% of the equatorial East Africa domain (30°–40°E, 5°S–5°N), while only 30% of the region responds to central and eastern Indian Ocean SSTAs. Evidence of an influential Indian Ocean dipole mode does not emerge from the analysis. The mechanisms of this influence are diagnosed using atmospheric moisture budget and moist static energy analyses, with reference to Kelvin and Rossby wave generation as in the Gill model, but in the presence of complicated topography and nonzero background flows. Wind convergence anomalies in a moist environment primarily support precipitation anomalies in all cases, while changes in atmospheric instability are largely controlled by low-level moisture. Central and eastern Indian Ocean SSTAs change circulations and precipitation locally, but the remote influence on East Africa is weaker than that of the western Indian Ocean SSTAs. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	East african precipitation; Greater horn of africa; Indian ocean dipole; Interannual variability; Kenya precipitation; Short rains; SST forcing; Tropical africa rainfall; WRF
语种	英语
scopus关键词	annual variation; climate modeling; Indian Ocean Dipole; precipitation (climatology); rainfall; regional climate; sea surface temperature; East Africa; 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/145461
作者单位	Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, 1 University Station C1100, Austin, TX, United States
推荐引用方式 GB/T 7714	Liu W.,Cook K.H.,Vizy E.K.. Influence of Indian Ocean SST regionality on the East African short rains[J],2020,54.
APA	Liu W.,Cook K.H.,&Vizy E.K..(2020).Influence of Indian Ocean SST regionality on the East African short rains.Climate Dynamics,54.
MLA	Liu W.,et al."Influence of Indian Ocean SST regionality on the East African short rains".Climate Dynamics 54(2020).