Collaborative Research: Convection and Rainfall Enhancement over Mountainous Tropical Islands

热带岛屿上的降雨量比附近的海洋地区多福尔斯。岛屿降雨量的增加有多种原因，包括白天岛屿加热和相关海风以及吹过山区岛屿的风引发雷暴。虽然岛屿降雨看起来像是一个地方性的研究课题，但对它的更好理解有几个好处，可以贯穿全球天气和气候的研究。例如，热带太平洋西部的大岛（如婆罗洲、巴布亚新几内亚和苏门答腊）的降雨量会影响沿着赤道太平洋盆地的风型，影响时间尺度上的天气（几周）和气候（季节）。此外，更深入地了解热带地区的高雷暴仍然是改善天气预报和减少气候变化预测不确定性的主要障碍。与此相关，研究岛屿降雨可能有助于解决以下问题：在潮湿或干燥的土壤上降雨量是否更大，以及为什么;这些问题对于理解洪水和干旱的持续性很重要。最后，了解岛屿降雨如何取决于附近海洋的温度仍然是一个挑战。这种温度依赖性不仅对气候变化中极端降雨的社会影响很重要，而且还因为所有陆地（特别是热带岛屿）径流中发现的溶解矿物质可以在数百万年的时间内调节大气二氧化碳含量和全球温度。该项目的目标是通过使用高分辨率的大气数值模式模拟来研究岛屿增雨如何取决于岛屿环境的多个因素，从而解决这些跨越天气、当前气候和过去气候的问题。这些因素包括附近海洋的温度、岛屿的湿度和高度、撞击岛屿的风的强度以及数值模型中模拟的区域大小。 这一研究项目将通过研究热带对流如何受到岛屿环境局部方面的影响，增进对调节气候的热带对流过程的了解。该研究项目支持一名研究生，他将获得气候动力学方面的培训，并为学术界或商业天气预测的教学和研究事业做好准备，从而维持气候研究卓越所需的人力资源库。将制作公开提供的教学录像，说明与岛屿雷暴和降雨有关的中心概念，包括海风和一天中触发雷暴的模式。将向本科生、研究生和博士后研究人员提供一套工具，用于分析高分辨率大气数值模式产生的输出。

More rain falls over tropical islands than nearby ocean areas. This enhancement of island rainfall occurs for multiple reasons, including triggering of thunderstorms by daytime heating of islands and associated sea breezes, as well as by winds blowing over mountainous islands. Although island rainfall may seem like a local subject of study, an improved understanding of it has several benefits that cut across study of global weather and climate. For example, rainfall over the large islands of the western Tropical Pacific (such as Borneo, Papua New Guinea, and Sumatra) influences wind patterns along the equatorial Pacific basin at both weather (a few weeks) and climate (seasonal) time scales. Also, a deeper understanding of tall thunderstorms in the tropics remains a major obstacle to better weather forecasts and reducing uncertainty in climate change projections. Connected with this, studying island rainfall may help address questions about whether it tends to rain more over wet or dry soils and why; these questions are important for understanding the persistence of floods and droughts. Finally, understanding how island rainfall depends on the temperature of the nearby ocean remains a challenge. This temperature-dependence is important not only for the societal impacts of rainfall extremes in a changing climate, but also because dissolved minerals found in the runoff from all land - but particularly tropical islands - can regulate atmospheric carbon dioxide content and global temperature over periods of millions of years. The goal of this project is to address these questions that cut across weather, current climate, and past climate, by using high-resolution numerical model simulations of the atmosphere to investigate how island rainfall enhancement depends on multiple factors of the island environment. These factors include the temperature of the nearby ocean, the wetness and height of the island, the strength of the winds impinging on the island, and the size of the region simulated in the numerical model. This research project will advance knowledge about the tropical convection processes that regulate the climate, by studying how tropical convections are influenced by local aspects of the island environment. The research project supports a graduate student who will gain training in climate dynamics and preparation for a career in teaching and research in academia or commercial weather prediction, thus sustaining the pool of human resources required for excellence in climate research. Publicly available instructional videos will be produced to illustrate central concepts associated with island thunderstorms and rainfall, including sea-breezes and the pattern of thunderstorm triggering over the day. A set of tools for analyzing the output generated by the high-resolution numerical model of the atmosphere will be made available to undergraduate students, graduate students, and postdoctoral researchers.