Surface Boundary Forcing and Sahelian Climate Variability and Anomalies

非洲萨赫勒是半干旱的热带稀树草原地区，北部与撒哈拉沙漠接壤，南部是更肥沃的地区，统称为苏丹。这一过渡生态区容易受到温度和降雨量的强烈季节性变化的影响。从20世纪60年代末S观察到的萨赫勒长期干旱，数百万人遭受饥荒和流离失所，以及1980年代S的部分恢复，被认为是受到海表面温度异常的显著影响，但也受到该地区在20世纪末发生的重大土地利用和土地覆盖变化的影响。加州大学洛杉矶分校的研究人员将进行一系列数值气候模拟实验，以更好地评估不同(日、季、年际和更长)时间尺度上海温、陆地表面强迫和陆地-大气耦合强度的相对作用。大气环流模型、区域气候模型、生物圈和动态植被模型将结合在一起，以探索这些潜在因素之间的反馈循环和变化。建模研究将包括对最近的卫星图像和非洲季风多学科运动(AMMA)的观测数据进行比较，以便更好地预测这一重要区域潜在的人类导致的气候变化。这项工作将支持一名博士后研究人员和一名研究生的研究和教育。

The African Sahel is the semi-arid tropical savanna region bordered by the Sahara in the north and more fertile regions to the south, collectively known as the Sudan. This transitional ecoregion is subject to strong seasonal variations in temperature and rainfall. A long running drought in the Sahel observed from the late 1960's, which afflicted millions by famine and dislocation, and a partial recovery in the 1980's has been believed to be significantly influenced by sea surface temperature (SST) anomalies, but also by significant land use and land cover changes taken place in the region during the late 20th century. UCLA investigators will conduct a series of numerical climate modeling simulation experiments to better evaluate the relative roles of SST, land surface forcings and land-atmosphere coupling strength over different (diurnal, seasonal, interannual and longer) time scales. General circulation models, regional climate models, biosphere and dynamic vegetation models will be coupled to explore feedback loops and changes amongst these potential factors. The modeling studies will include comparisons of recent satellite imagery and observational data from the African Monsoon Multidisciplinary (AMMA) campaign, in order to better project potential human-induced climate change in this significant region.The work will support the research and education of a post-doctoral researcher and a graduate student.