Idealized Models for Tropical Climate Dynamics

热带气候动力学的理想化模型

• 批准号: 1008847
• 负责人: Adam Sobel
• 金额: $ 50.09万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1008847&HistoricalAwards=false
• 关键词: Idealized; Models; Tropical; Climate; Dynamics

This project investigates fundamental questions in tropical climate dynamics through the development and use of idealized models. Simple models are of interest because the chains of cause and effect are less intricate than in sophisticated climate and atmospheric circulation models. The project has two components, the firsts of which is an investigation of the interaction of extratropical baroclinic eddies (essentially frontal weather system) with the Hadley circulation (i.e. the large-scale overturning circulations in the tropics) and the intertropical convergence zones (ITCZs, or zones of enhanced cloudiness and rainfall near the equator). The influence of extratropical eddies on the trade winds and the zonally averaged tropical rainfall distribution will be a primary focus of the research. The second component of the research involves development of methodology for applying the weak temperature gradient (WTG) approximation to single column models (SCM) of the atmosphere. The WTG approximation is a simple representation of the fact that tropical atmospheric temperatures are horizontally homogeneous because of the geostrophic adjustment process, and work conducted here will advance understanding of the implications of the approximation for the behavior of SCMs and the observed tropical atmosphere. In particular, the extent to which the SCM can mimic the dependence of precipitation (a key SCM output) on tropical sea surface temperature, surface wind speed, and horizontal moisture advection in a state-of-the-art climate model.In addition to advancing the science of tropical climate dynamics, the project has broader impacts through the training and education of a graduate student and a postdoctoral research associate. In addition, source code for software developed over the course of the project will be made available online for the use of the research community.

该项目通过开发和使用理想模型来研究热带气候动力学中的基本问题。简单模式之所以令人感兴趣，是因为因果链没有复杂的气候和大气环流模式那么复杂。该项目有两个组成部分，第一部分是调查温带斜压涡旋（本质上是锋面天气系统）与哈德利环流（即热带地区的大规模翻转环流）和热带辐合带（itcz，或赤道附近云量和降雨增强的区域）的相互作用。温带涡旋对信风和纬向平均热带降水分布的影响将是研究的重点。研究的第二个组成部分涉及将弱温度梯度（WTG）近似应用于大气单柱模型（SCM）的方法发展。由于地转调整过程，WTG近似是热带大气温度水平均匀这一事实的简单表示，这里进行的工作将促进对SCMs行为和观测到的热带大气近似含义的理解。特别是，在最先进的气候模式中，SCM可以在多大程度上模拟降水（一个关键的SCM输出）对热带海面温度、地面风速和水平水汽平流的依赖。除了推进热带气候动力学科学之外，该项目还通过培训和教育一名研究生和一名博士后研究助理产生了更广泛的影响。此外，在项目过程中开发的软件源代码将在网上提供给研究社区使用。