气候变化领域集成服务门户(CCPortal): Seasonal asymmetry of equatorial East African rainfall projections: understanding differences between the response of the long rains and the short rains to increased greenhouse gases

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DOI	10.1007/s00382-020-05350-y
	Seasonal asymmetry of equatorial East African rainfall projections: understanding differences between the response of the long rains and the short rains to increased greenhouse gases
	Cook K.H.; Fitzpatrick R.G.J.; Liu W.; Vizy E.K.
发表日期	2020
ISSN	0930-7575
起始页码	1759
结束页码	1777
卷号	55
英文摘要	Ensemble simulations with a regional climate model on a large domain and 30-km resolution are used to understand why projected precipitation changes under greenhouse gas-forcing are asymmetric across seasons in equatorial East Africa, with rainfall increasing during the short rains (October through December) but not during the long rains (March through May). The model captures an accurate simulation of observed East African precipitation improving over coupled GCM simulations. Future simulations are generated by increasing atmospheric CO2 according to the RCP8.5 scenario and adding anomalies to observed SSTs as well as initial and lateral boundary conditions derived from coupled GCM simulations. In November, simulated rainfall rates increase by approximately one-third over much of equatorial East Africa by the mid-twenty-first century, and double by the end of the century. The long rains are not significantly increased. The difference in the seasonal response is attributed to differences in the background state. The East African short rains are greatest in November, more than 1 month after the autumnal equinox, when the climatological basic state is in a solstitial pattern. The well-defined heat low over southern Africa and the South Indian Ocean subtropical high to its east are intensified, leading to enhanced moisture convergence over equatorial East Africa. In contrast, the long rains are near their maximum on the vernal equinox, with a continental thermal low centered near the equator that is insensitive to twenty-first century greenhouse gas-induced changes in the subtropical atmospheric hydrodynamics. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Angola low; East Africa; East Africa precipitation projections; East Africa precipitation trends; East African climate change projections; East African long rains; East African precipitation; East African short rains; Mascarene high; South Indian high; Turkana channel
语种	英语
scopus关键词	asymmetry; atmospheric moisture; carbon dioxide; climate modeling; computer simulation; greenhouse gas; hydrodynamics; precipitation assessment; rainfall; regional climate; seasonal variation; temperature anomaly; East Africa
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/145341
作者单位	Department of Geological Sciences, University of Texas at Austin, Austin, TX, United States; University of California at Davis, Davis, CA, United States
推荐引用方式 GB/T 7714	Cook K.H.,Fitzpatrick R.G.J.,Liu W.,et al. Seasonal asymmetry of equatorial East African rainfall projections: understanding differences between the response of the long rains and the short rains to increased greenhouse gases[J],2020,55.
APA	Cook K.H.,Fitzpatrick R.G.J.,Liu W.,&Vizy E.K..(2020).Seasonal asymmetry of equatorial East African rainfall projections: understanding differences between the response of the long rains and the short rains to increased greenhouse gases.Climate Dynamics,55.
MLA	Cook K.H.,et al."Seasonal asymmetry of equatorial East African rainfall projections: understanding differences between the response of the long rains and the short rains to increased greenhouse gases".Climate Dynamics 55(2020).