气候变化领域集成服务门户(CCPortal): Future changes in rainfall associated with ENSO; IOD and changes in the mean state over Eastern Africa

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DOI	10.1007/s00382-018-4239-7
	Future changes in rainfall associated with ENSO; IOD and changes in the mean state over Eastern Africa
	Endris H.S.; Lennard C.; Hewitson B.; Dosio A.; Nikulin G.; Artan G.A.
发表日期	2019
ISSN	0930-7575
起始页码	2029
结束页码	2053
卷号	52 期号:2020-03-04
英文摘要	This study examines the projected changes in the characteristics of the El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) in terms of mean state, intensity and frequency, and associated rainfall anomalies over eastern Africa. Two regional climate models driven by the same four global climate models (GCMs) and the corresponding GCM simulations are used to investigate projected changes in teleconnection patterns and East African rainfall. The period 1976–2005 is taken as the reference for present climate and the far-future climate (2070–2099) under Representative Concentration Pathway 8.5 (RCP8.5) is analyzed for projected change. Analyses of projections based on GCMs indicate an El Niño-like (positive IOD-like) warming pattern over the tropical Pacific (Indian) Ocean. However, large uncertainties remain in the projected future changes in ENSO/IOD frequency and intensity with some GCMs show increase of ENSO/IOD frequency and intensity, and others a decrease or no/small change. Projected changes in mean rainfall over eastern Africa based on the GCM and RCM data indicate a decrease in rainfall over most parts of the region during JJAS and MAM seasons, and an increase in rainfall over equatorial and southern part of the region during OND, with the greatest changes in equatorial region. During ENSO and IOD years, important changes in the strength of the teleconnections are found. During JJAS, when ENSO is an important driver of rainfall variability over the region, both GCM and RCM projections show an enhanced La Niña-related rainfall anomaly compared to the present period. Although the long rains (MAM) have little association with ENSO in the reference period, both GCMs and RCMs project stronger ENSO teleconnections in the future. On the other hand, during the short rains (OND), a dipole future change in rainfall teleconnection associated with ENSO and IOD is found, with a stronger ENSO/IOD related rainfall anomaly over the eastern part of the domain, but a weaker ENSO/IOD signal over the southern part of the region. This signal is consistent and robust in all global and regional model simulations. The projected increase in OND rainfall over the eastern horn of Africa might be linked with the mean changes in SST over Indian and Pacific Ocean basins and the associated Walker circulations. © 2018, The Author(s).
英文关键词	CMIP5; CORDEX; Eastern Africa; Rainfall; RCM; Teleconnections
语种	英语
scopus关键词	anomaly; climate modeling; El Nino-Southern Oscillation; future prospect; Indian Ocean Dipole; rainfall; sea surface temperature; teleconnection; uncertainty analysis; Walker circulation; weather forecasting; East Africa; Indian Ocean; Indian Ocean (Tropical); Pacific Ocean; Pacific Ocean (Tropical)
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/146544
作者单位	IGAD Climate Prediction and Applications Centre (ICPAC), Nairobi, Kenya; Climate System Analysis Group, University of Cape Town, Cape Town, South Africa; European Commission Joint Research Centre, Ispra, Italy; Rossby Centre, Swedish Meteorological and Hydrological Institute, Norrköping, Sweden
推荐引用方式 GB/T 7714	Endris H.S.,Lennard C.,Hewitson B.,et al. Future changes in rainfall associated with ENSO; IOD and changes in the mean state over Eastern Africa[J],2019,52(2020-03-04).
APA	Endris H.S.,Lennard C.,Hewitson B.,Dosio A.,Nikulin G.,&Artan G.A..(2019).Future changes in rainfall associated with ENSO; IOD and changes in the mean state over Eastern Africa.Climate Dynamics,52(2020-03-04).
MLA	Endris H.S.,et al."Future changes in rainfall associated with ENSO; IOD and changes in the mean state over Eastern Africa".Climate Dynamics 52.2020-03-04(2019).