A Modelling and Empirical Study of the Climate of the Lake Victoria Basin of Eastern Africa

该项目旨在研究东非中部地区降雨分布中的干-湿-干-湿维多利亚湖盆地波浪结构（LVB-WS）。这是维多利亚湖盆地 (LVB) 气候的最主要特征。此前很少有研究致力于调查详细的气候学和年际变率、对气候变化的响应以及这种气候特征的原因。研究人员将弥补这一知识差距，开展以下补充性研究活动：(i) LVB-WS 气候学和年际变率：结合基于现场和卫星数据集的分析，对 LVB-WS 的气候学和年际变率进行改进和详细描述；(ii) LVB-WS 对气候变化的响应：执行和分析与普林斯顿海洋模型 (RegCM3-POM) 区域相结合的社区区域气候模型版本 3在当前和未来的气候情景下对LVB进行气候模型模拟，以推断LVB-WS的气候变化预测，并了解造成预测变化的物理过程的相对作用；（iii）负责LVB-WS发展和演化的物理机制：基于区域RegCM3-POM湖泊-大气耦合模型进行机理数值模拟，以确定LVB-WS的成因。这些机制包括区域山脊的作用、维多利亚湖主要气候模式的环流和热力学的作用，以及与区域气候系统大范围背景环流变化相关的气候效应。拟议研究的更广泛影响是教育性的，并有可能增进我们对维多利亚湖水动力和流域气候耦合变化的认识和理解。该项目将为与 LVB 相关的多项备受瞩目的气候计划和活动做出贡献，例如国际努力 CORDEX（协调区域降尺度实验）和下一次政府间气候变化专门委员会 (IPCC) 第五次评估报告 (AR5) 评估。与非洲气候中心和其他国际组织的合作将促进气候信息产品的改进，为 LVB 地区的政策决策提供信息。

The project aims to study the dry-wet-dry-wet Lake Victoria Basin Wave Structure (LVB-WS) in the distribution of rainfall across the central region of East Africa. This is the most dominant feature of the climate over Lake Victoria basin (LVB). Very few studies have previously been devoted to investigate the detailed climatology and interannual variability, the response to climate change and the causes of this climatic feature. The investigators will address this knowledge gap to perform the following complementally research activities:(i) LVB-WS Climatology & interannual variability: Produce improved and detailed description of the climatology and interannual variability of the LVB-WS using a combination of analyses based on in-situ and satellite data sets;(ii) Response of the LVB-WS to climate change: Perform and analyse the community Regional Climate Model-version 3 coupled to the Princeton Ocean Model (RegCM3-POM) regional climate model simulations over LVB under present and future climate scenarios to infer climate change projections of the LVB-WS and understand the relative role of the physical processes responsible for the projected changes;(iii) Physical mechanisms responsible for the development & evolution of the LVB-WS: Conduct mechanistic numerical simulations based on the regional RegCM3-POM lake-atmosphere coupled model to determine the causes of the LVB-WS. These mechanisms include the role of regional mountain ridges, the role of the dominant climatic modes of circulation and thermodynamics of Lake Victoria, and climatic effects associated with changes in the large-scale background circulation of the regional climate system.Broader impacts of the proposed research are educational and in the potential to advance our knowledge and understanding of the coupled variability of Lake Victoria hydrodynamics and the basin-wide climate. The project will contribute to several high profile climate programs and activities related to LVB such as the international effort CORDEX (Coordinated Regional Downscaling Experiment) and the next Intergovernmental Panel on Climate Change (IPCC) 5th assessment report (AR5) assessment. Collaboration with African climate centers and other international organizations will promote improvement of climate information products to inform policy decisions in the LVB region.