气候变化领域集成服务门户(CCPortal): The role of mesoscale convective systems in the diurnal cycle of rainfall and its seasonality over sub-Saharan Northern Africa

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DOI	10.1007/s00382-018-4162-y
	The role of mesoscale convective systems in the diurnal cycle of rainfall and its seasonality over sub-Saharan Northern Africa
	Liu W.; Cook K.H.; Vizy E.K.
发表日期	2019
ISSN	0930-7575
起始页码	729
结束页码	745
卷号	52 期号:2020-01-02
英文摘要	This study evaluates the role of MCSs in the total rainfall distribution as a function of season from a climatological perspective (1998–2014) over sub-Saharan northern Africa and examines how the diurnal cycle of rainfall changes with season. Tropical Rainfall Measuring Mission (TRMM) 3B42V7 rainfall estimates and European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis are used to evaluate the climatology. The percentages of the full TRMM precipitation delivered by MCSs have meridional structures in spring, fall and winter, ranging from 0 to 80% across sub-Saharan northern Africa, while the percentages are homogenous in summer (> 80%). The diurnal cycles of MCS-associated precipitation coincide with the full TRMM rainfall. Attributes of MCSs, including size, count, and intensity, vary synchronously with the diurnal cycle of rainfall. The diurnal peaks are classified into three categories: single afternoon peak, continuous afternoon peak, and nocturnal peak. Single afternoon peaks dominate in spring and fall while continuous afternoon and nocturnal peaks are more common in summer, indicating the seasonality of the diurnal cycle. The continuous afternoon peak combines rainfall from two system types—one locally-generated and one propagating. The seasonality of the diurnal cycle is related to the seasonality of MCS lifetimes, and propagation speeds and directions. The moisture component of the MSE profile contributes to the instability most in summer when convection is more frequent. Low-level temperature, which is related to surface warming and sensible heat fluxes, influences the instability more during winter and spring. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	African easterly waves; African wave disturbances; Diurnal cycle of precipitation; MCS; Moist static energy; SAHEL rainfall; West Africa
语种	英语
scopus关键词	atmospheric dynamics; convective system; diurnal variation; easterly wave; mesoscale meteorology; precipitation (climatology); rainfall; seasonality; thunderstorm; TRMM; Sub-Saharan Africa; West 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/146625
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.. The role of mesoscale convective systems in the diurnal cycle of rainfall and its seasonality over sub-Saharan Northern Africa[J],2019,52(2020-01-02).
APA	Liu W.,Cook K.H.,&Vizy E.K..(2019).The role of mesoscale convective systems in the diurnal cycle of rainfall and its seasonality over sub-Saharan Northern Africa.Climate Dynamics,52(2020-01-02).
MLA	Liu W.,et al."The role of mesoscale convective systems in the diurnal cycle of rainfall and its seasonality over sub-Saharan Northern Africa".Climate Dynamics 52.2020-01-02(2019).