Multi-scale Analysis of Congo Basin Precipitation: Understanding the Regional Rainfall Climatology and the Potential for Change

刚果盆地降水的多尺度分析：了解区域降雨气候学和变化潜力

• 批准号: 1939880
• 负责人: Kerry Cook
• 金额: $ 82.27万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-15 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1939880&HistoricalAwards=false
• 关键词: Multi; scale; Analysis; Congo; Basin

The Congo Basin rain forest is known around the world for its biodiversity and rich cultural heritage. But the rains that provide water resources to the people and ecosystems of the forest are understudied and fundamental aspects of their behavior have not been fully documented. One challenge to understanding rainfall in the basin is lack of observations, as economic hardship and political instability have hampered development of weather observing networks. Another challenge is that much of the rainfall comes from mesoscale convective systems (MCSs), intense propagating thunderstorms like the ones seen over the central US in summer, which are difficult to observe in detail.Research performed under this award seeks to characterize the rain-bearing weather systems of the Congo Basin, including their seasonality, connections to the large-scale atmospheric circulation, moisture distribution, and the extent to which evaporation and transpiration from the vegetated land surface serves as a moisture source for rainfall. The work takes advantage of recent datasets that make up for the lack of ground-based observations through satellites and global atmospheric data assimilation systems. The datasets have high enough resolution to track MCSs and determine their formation regions, propagation paths, total contribution to precipitation, and interaction with the large-scale environment.Further research is conducted using the Weather Research and Forecasting (WRF) model, a regional model which can capture MCS dynamics. Here WRF is applied in a triply nested configuration over Central Africa with boundary forcing from reanalysis products, which ensure that the large-scale features of the simulations mimic their real-world counterparts. In some simulations the boundary forcing is modified to represent the effects of future climate change based on output from global climate models. The impact of simulated future precipitation change on the rain forest is assessed using a Potential Vegetation Model.The work is of societal as well as scientific interest given the vulnerable population of the region and its importance as a biodiversity hotspot. In addition, the Principal Investigators conduct local outreach through the Jackson School's GeoForce program, which introduces students from rural and inner-city schools to geoscience by conducting field trips and other activities. Geology has been the primary focus of GeoForce, and outreach efforts under this award bring weather and climate into the mix of topics addressed in the program. The project also supports two graduate students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

刚果盆地雨林以其生物多样性和丰富的文化遗产而闻名于世。 但是，为人类和森林生态系统提供水资源的雨水却没有得到充分的研究，它们行为的基本方面也没有得到充分的记录。 由于经济困难和政治不稳定阻碍了天气观测网络的发展，因此缺乏观测是了解该流域降雨量的一个挑战。 另一个挑战是，大部分降雨来自中尺度对流系统（MCS），即像美国中部夏季那样的强烈传播雷暴，很难详细观察。该奖项下进行的研究旨在描述刚果盆地的降雨天气系统，包括其季节性，与大尺度大气环流的联系，水分分布，以及从植被覆盖的陆地表面蒸发和蒸腾作为降雨的水分来源的程度。 这项工作利用了最近的数据集，弥补了通过卫星和全球大气数据同化系统进行地面观测的不足。该数据集具有足够高的分辨率来跟踪MCS，并确定其形成区域，传播路径，降水的总贡献，以及与大尺度环境的相互作用。 在这里，WRF被应用在一个三重嵌套配置在中部非洲与边界强迫再分析产品，这确保了模拟的大规模功能模仿他们的现实世界的同行。 在一些模拟中，边界强迫被修改以代表基于全球气候模式输出的未来气候变化的影响。模拟未来降水变化对雨林的影响是使用潜在植被模型进行评估的。考虑到该地区脆弱的人口及其作为生物多样性热点的重要性，这项工作具有社会和科学意义。 此外，主要研究人员通过杰克逊学校的GeoForce计划进行当地推广，该计划通过进行实地考察和其他活动向来自农村和市中心学校的学生介绍地球科学。 地质学一直是GeoForce的主要重点，该奖项下的外联工作将天气和气候纳入该计划中解决的主题组合。 该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Hydrodynamics of regional and seasonal variations in Congo Basin precipitation

• DOI: 10.1007/s00382-021-06066-3
• 发表时间: 2021-09
• 期刊: Climate Dynamics
• 影响因子: 4.6
• 作者: K. Cook;E. Vizy