Midlatitude Storm Track Dynamics on a Cloudy Earth

多云地球上的中纬度风暴路径动力学

基本信息

批准号：
1760402
负责人：
Tapio Schneider
金额：
$ 59.93万
依托单位：
California Institute of Technology
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-05-15 至 2021-04-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1760402&HistoricalAwards=false
关键词：
Midlatitude Storm Track Dynamics Cloudy

项目摘要

Large-scale wind storms in the extratropics occur preferentially in regions known as storm tracks. In the Northern Hemisphere, storm tracks span the North Pacific and North Atlantic, and the storms in them shape the regional weather, for example, in the Pacific Northwest, the eastern United States, and Europe. Because storm tracks are the principal conduit through which energy and moisture are transported in the climate system, they are also crucially important for controlling climatic features such as the global distributions of rainfall and surface temperature. Recent observations and simulations with numerical atmosphere models have revealed that climate changes modulate various aspects of storm tracks. For example, storm tracks generally shift poleward as the climate warms and equatorward as the climate cools. However, fundamental questions about the structure and variability of storm tracks and their response to climate changes remain unanswered. For example, it is unclear what controls where storm tracks terminate over the North Pacific and North Atlantic, what their observed low-frequency variations depend on, and how these and other aspects respond to climate changes. Answering such questions requires an improved understanding of how storm tracks interact with stationary weather patterns, such as the Aleutian Low, and how they interact with clouds which on one hand are products of storms and on the other hand modify, through their absorption/reflections/emission, the environments where storm tracks operate. This project aims to answer such questions, using observational data and targeted experiments with idealized atmosphere models that serve as a computational laboratory. The project will examine the processes responsible for controlling storm tracks by analyzing observations and simulations with an atmosphere model that is simplified in some respects (e.g., it may simplify or eliminate continental effects altogether) but contains relatively sophisticated representations of clouds. The goal is study the fundamental processes controlling the structure and variability of storm tracks and their interactions clouds, culminating in theories and conceptual models of storm track dynamics. This research will bridge the gap between state-of-the-art comprehensive climate models and fundamental physical understanding. The conceptual models to be developed under this project will provide a framework for assessing weather forecasting and climate models and will suggest ways for improving them. The project will assess and potentially enhance predictability of major weather hazards in mid-latitudes, including extreme storms, droughts, and floods, on sub-seasonal and longer timescales. It will also train a new generation of scientists who are fluent in the use of the full breadth of state-of-the-art tools in atmosphere and climate dynamics, from theory to comprehensive numerical models. This will be achieved by directly funding a postdoctoral scholar, who, by the end of this project, will be ready to commence her independent career in climate and large-scale dynamics; by partially funding a graduate student at the start of his or her research career; and by disseminating results through publications, conference presentations, colloquia, and classroom teaching. The research project will also broaden the range of available research tools by making the program code of models used and developed in this research publicly available.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.

气流中的大规模风暴优先发生在称为风暴轨道的地区。在北半球，风暴轨道跨越了北太平洋和北大西洋，其中的风暴塑造了区域天气，例如，在太平洋西北，美国东部和欧洲。由于风暴轨道是在气候系统中运输能量和水分的主要导管，因此它们对于控制气候特征（例如雨水和表面温度的全球分布）也至关重要。使用数值大气模型的最新观察和模拟表明，气候变化调节了风暴轨迹的各个方面。例如，随着气候的温暖和赤道，风暴轨道通常会向极移动。但是，关于风暴轨迹的结构和可变性及其对气候变化的反应的基本问题尚未得到解答。例如，目前尚不清楚哪些控制风暴跟踪在北太平洋和北大西洋上终止的地方，他们观察到的低频变化依赖于什么，以及这些方面和其他方面对气候变化的反应。回答此类问题需要对风暴跟踪如何与固定天气模式（例如Aleutian Low）相互作用，以及它们如何与云的相互作用，一方面是风暴产物，另一方面通过其吸收/反射/排放来修改，风暴轨迹轨迹的环境进行了修改。该项目旨在使用观察数据和具有理想化气氛模型的目标实验来回答此类问题，这些模型是计算实验室。该项目将通过分析具有大气模型的观测值和模拟来检查负责控制风暴轨道的过程，该模型在某些方面简化了（例如，它可能完全简化或消除大陆效应），但包含云的相对复杂的表示。目的是研究控制风暴轨迹及其相互作用云的结构和可变性的基本过程，最终导致风暴轨道动态的理论和概念模型。这项研究将弥合最新的全面气候模型与基本的物理理解之间的差距。在此项目下要开发的概念模型将为评估天气预测和气候模型提供一个框架，并将提出改善它们的方法。该项目将评估并有可能增强中期中期和较长时间尺度上的极端风暴，干旱和洪水在内的主要天气危害的可预测性。它还将培训新一代的科学家，他们能够精通大气和气候动态中最新工具的全部广度，从理论到全面的数值模型。这将通过直接为博士后学者提供资金来实现，后者在该项目结束时将准备开始在气候和大规模动态方面的独立职业。通过在其研究生涯开始时部分资助研究生；并通过出版物，会议演讲，座谈会和课堂教学来传播结果。该研究项目还将通过公开提供本研究中使用和制定的计划模型守则来扩大可用的研究工具的范围。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响评估标准，被认为值得通过评估来获得支持。