Studies in Ocean-Land-Atmosphere Interaction

整个热带地区的降雨分布对数十亿人有着生死攸关的影响。随着地球仪变暖，热带降雨量可能会发生变化，但全球气候模型对这些变化的影响却没有达成一致。热带降雨受大尺度大气环流与小尺度对流之间以及大尺度环流与陆地表面和海洋边界层之间的复杂相互作用的控制。Neelin和他的团队将使用一系列数值模型，从完整的全球气候模型到热带大气的理想化模型，再到简单的诊断模型，以及以前未充分使用的观测数据，以解决热带降雨的四个重要基本问题：i）全球变暖下热带降雨如何变化？ii）他的准平衡假说在解释热带大气结构方面的可靠性如何，以及这一假说对大尺度环流的影响如何？iii）湿能量在热带大气中是如何传输的，是什么决定了大气对流的稳定性？（iv）潮湿大气的环流如何将信息从一个地区传递到另一个地区？这项研究的更广泛影响在于它有可能改进用于预测热带天气和气候的模型，改进对热带降水如何随着气候变化而变化的预测，并培训研究生和博士后研究科学家。

The distribution of rainfall across the tropics has life-or-death implications for billions of people. Tropical rainfall may change as the globe warms, but there is a little agreement among global climate models as to what these changes will be. Tropical rainfall is governed by complex interactions between the large-scale atmospheric circulation and small-scale convection and between the large-scale circulation and the land surface and marine boundary layer. Neelin and his group will use a hierarchy of numerical models, ranging from full global climate models, to idealized models of the tropical atmosphere, to simple diagnostic models, together with formerly under-used observational data to address four fundamental problems important for tropical rainfall: i) how does tropical rainfall change under global warming? ii) how reliable is his quasi-equilibrium hypothesis for explaining the structure of the tropical atmosphere, and what are the implications of this hypothesis for the large-scale circulation? iii) how is moist energy transported in the tropical atmosphere, and what determines the stability of the atmosphere to convection? iv) how does the circulation of a moist atmosphere transmit information from one region to another?Broader impacts of this research are in its potential to improve models used to forecast tropical weather and climate, in leading to improved projections of how tropical precipitation will change as climate changes, and in training graduate students and post-doctoral research scientists.