Addressing Problems in Tropical Atmospheric Dynamics Using Idealized Global Climate Models

我们对气候系统知识的持续空白出现在热带大气中，在那里，在非常小的空间尺度上的运动在热量和水的垂直输送中扮演着超大的角色。这些运动很难纳入全球气候模型，导致气候模拟的不确定性。该项目旨在促进我们对热带气候的关键基本特征的理解，并解决将这些运动纳入其中的不同建模方法如何影响这些关键特征。研究战略需要创建不同复杂性的气候模型，并在热辐射和水蒸气之间建立现实的相互作用。在这些模拟中，研究人员将研究热带降雨的时间平均分布和热带降雨在不同频率和空间尺度上的组织，以及随着气候变暖热带风和降雨突然重组的可能性。研究任务将帮助培养研究生和早期职业科学家。该项目遵循一种独特的气候理论方法，通过剥离连续的复杂性层来构建和分析气候模型的系统层次。研究的热带动力学包括Hadley环流的位置和结构、对流耦合波、Madden-Julian振荡以及热带地区对超旋转的敏感性。与传统观点不同的是，该项目最初将专注于模拟，不对垂直热量和水分通量进行额外处理，补充该模型基于通常用于气候预测的水平分辨率本身可以产生的结果。这一战略将提供一个基准，以促进研究不同通量处理或网格尺寸小得多的模式模拟的多样性。然后，该项目将构建一个比以前更灵活地处理这些垂直通量的模型。在向公众传达气候理论和气候变化的基本概念方面，层次化方法具有很大的教学价值。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A persistent gap in our knowledge of the climate system occurs in the tropical atmosphere where motions on very small spatial scales play an outsized role in the vertical transport of heat and water. These motions are very difficult to incorporate into global climate models, resulting in uncertainty in climate simulations. This project aims to advance our understanding of key fundamental features of the tropical climate and address how different modeling approaches to incorporate those motions affect these key features. The research strategy entails creating climate models of differing complexity and with realistic interaction between thermal radiation and water vapor. In these simulations, the investigators will examine the time-averaged tropical rainfall distribution and the organization of tropical rainfall on different frequencies and spatial scales, as well as the potential for abrupt reorganization of the tropical winds and rainfall as the climate warms. The research tasks will help train graduate students and early career scientists.The project follows a distinctive approach to climate theory involving the construction and analysis of a systematic hierarchy of climate models by peeling off successive layers of complexity. The examined tropical dynamics include the position and structure of the Hadley Circulation, convectively coupled waves, the Madden-Julian Oscillation, and the susceptibility of the tropics to super-rotate. Deviating from conventional wisdom, the project will initially concentrate on simulations with no additional treatment of vertical heat and moisture fluxes, supplementing what the model can produce on its own based on a horizontal resolution commonly used for climate projections. This strategy will provide a benchmark to facilitate the study of the diversity of model simulations with differing treatments of fluxes or with much smaller grid size. The project will then construct a model with greater flexibility in handling these vertical fluxes than previously possible. The hierarchy approach with accessible results can have great pedagogical values in communicating the fundamental concepts in climate theory and climate change to the public.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.