气候变化领域集成服务门户(CCPortal): A convection-permitting model for the Lake Victoria Basin: evaluation and insight into the mesoscale versus synoptic atmospheric dynamics

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DOI	10.1007/s00382-019-05088-2
	A convection-permitting model for the Lake Victoria Basin: evaluation and insight into the mesoscale versus synoptic atmospheric dynamics
	Van de Walle J.; Thiery W.; Brousse O.; Souverijns N.; Demuzere M.; van Lipzig N.P.M.
发表日期	2020
ISSN	0930-7575
起始页码	1779
结束页码	1799
卷号	54
英文摘要	Aiming for an improved understanding of the different factors that determine the regional climate of the Lake Victoria Basin, the COSMO-CLM regional climate model is set up in a tropical, convection-permitting configuration and is directly nested in a recent reanalysis product (ERA5). The convection-permitting simulation outperforms state-of-the-art climate integrations that rely on convection parametrisations. Yet the domain-averaged model precipitation is larger than in the multi-observational ensemble, but the latter shows large spread. Overestimations of outgoing TOA shortwave and longwave radiation are much reduced compared to the COSMO-CLM CORDEX-Africa integration, but still suggest a general underestimation of the cloud fraction or frequency. Comparing the control with a no-lake simulation, the presence of Lake Victoria implies strong intensification of over-lake rainfall, but it only slightly increases the total domain-averaged precipitation. In addition, the easterly trade winds are shown to largely affect the mesoscale circulation and precipitation patterns. During daytime, fast trades and anabatic slope winds trigger convection at the lee-wind slopes, and subsidence over the basin. Slow trades allow the stationary air to produce spontaneous convective cells and to develop anabatic winds that result in orographic precipitation. During night-time, trade winds curl around the eastern branch of the East African Rift, generating a southerly and northerly evening convergence front entering the Lake Victoria Basin. Thus, our results highlight the key importance of the easterly trade winds and the complex orography in determining the total accumulation and location of precipitation in the Lake Victoria region. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Convection-permitting; Lake Victoria and Precipitation; Mesoscale circulation; Regional climate modelling
语种	英语
scopus关键词	atmospheric convection; atmospheric dynamics; climate modeling; mesoscale meteorology; parameterization; precipitation (climatology); synoptic meteorology; trade wind; East African Lakes; Lake Victoria
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/145629
作者单位	Department of Earth and Environmental Sciences, KU Leuven, Celestijnenlaan 200e, Leuven, Belgium; Department of Hydrology and Hydraulic Engineering, Vrije Universiteit Brussel, Brussels, Belgium; Department of Geography, Ruhr University Bochum, Bochum, Germany
推荐引用方式 GB/T 7714	Van de Walle J.,Thiery W.,Brousse O.,et al. A convection-permitting model for the Lake Victoria Basin: evaluation and insight into the mesoscale versus synoptic atmospheric dynamics[J],2020,54.
APA	Van de Walle J.,Thiery W.,Brousse O.,Souverijns N.,Demuzere M.,&van Lipzig N.P.M..(2020).A convection-permitting model for the Lake Victoria Basin: evaluation and insight into the mesoscale versus synoptic atmospheric dynamics.Climate Dynamics,54.
MLA	Van de Walle J.,et al."A convection-permitting model for the Lake Victoria Basin: evaluation and insight into the mesoscale versus synoptic atmospheric dynamics".Climate Dynamics 54(2020).