Analysis of Cirrus Clouds and Atmospheric Humidity with Cloud Resolving Numerical Model Calculations

利用云解析数值模型计算分析卷云和大气湿度

• 批准号: 1417659
• 负责人: Stephan Fueglistaler
• 金额: $ 44.31万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1417659&HistoricalAwards=false
• 关键词: Analysis; Cirrus; Clouds; Atmospheric; Humidity

Clouds pose a major challenge for global climate models, and uncertainties remain from process level understanding of cloud formation to processes that control the global cloud distribution. This project provides high-resolution numerical model simulations that will advance our theoretical understanding of the dominant factors controlling the genesis and global distribution of cirrus clouds, their impact on atmospheric water vapor, and the radiative impact of the combined cloud/vapor system. The role of cirrus clouds in dehydration of the upper troposphere remains not well quantified. The project's focus is on the importance of the interaction between cirrus clouds and the environment, and aims to bridge the gap in numerical modeling between the detailed study of individual cirrus clouds and the full domain-wide properties of the cloud field. The objectives of this project are (i) to determine the relative importance of nucleation processes (traditionally a focus of cirrus research) to post-nucleation processes (such as gravitational redistribution of condensate) on the cloud's microphysical properties; (ii) to quantify the impact of the cloud microphysical properties on the domain-wide moisture field (which in turn may feed back onto cloud formation) and domain-wide cloud field properties (such as occurrence frequency and ice water path); and (iii) to put the results from (i) and (ii) in context with the dynamical constraints on conditions favorable for cloud formation. The project focuses specifically on the role of cirrus in the tropical tropopause layer (TTL). Results from the project will contribute to improved understanding of the role of cirrus clouds for the regulation of water vapor in the TTL and stratosphere (with important consequences for the radiative forcing of climate, and stratospheric chemistry). The TTL is also in several ways ideal to study cirrus clouds and their interaction with the environment as both the dynamical conditions favoring in-situ cirrus cloud formation, as well as the large-scale structure of the TTL, can be reasonably well idealized.The objectives of the project are addressed with a wide range of numerical experiments with a cloud-resolving model that is scalable from very high resolution simulations at cloud scale to simulations of the entire tropics.Intellectual Merit :Insights from this project will help to improve parameterizations for general circulation models, leading to improved climate predictions.Broader Impacts :This project will help to reduce uncertainties in climate predictions, providing policy makers with more accurate information on future climate. The project will support a designated post-doctoral researcher with excellent reputation and a graduate student, thus training the next generation of cloud modeling specialists. Further, the PI will actively promote involvement of undergraduate students (in the form of Junior and Senior Theses) at Princeton University, thereby providing a first-hand experience and better understanding of climate science to a body of students that frequently follows careers in industry, finance and government.

云对全球气候模型构成了重大挑战，不确定性从对云形成的过程水平理解到控制全球云分布的过程。该项目提供了高分辨率的数值模型模拟，这些模拟将提高我们对控制卷云的起源和全球分布的主要因素的理论理解，它们对大气水蒸气的影响以及云/蒸气系统的辐射影响。卷云在对流层上部脱水中的作用仍未得到很好的量化。该项目的重点是卷云与环境之间相互作用的重要性，并旨在在单个卷心云的详细研究与云场的整个域范围内的详细研究之间弥合差距。该项目的目标是（i）确定成核过程（传统上是卷心核研究的重点）对核后过程（例如冷凝物重新分布）在云的微物理特性上的相对重要性； （ii）量化云微物理特性对域范围湿度场的影响（又可能反馈到云层形成）和范围范围的云场特性（例如出现频率和冰水路径）； （iii）将（i）和（ii）的结果与有利于云形成的条件的动态约束相同。该项目专门关注卷心在热带热带层（TTL）中的作用。该项目的结果将有助于提高人们对卷云在调节TTL和平流层调节水蒸气中的作用的理解（对气候的辐射强迫以及平流层化学的辐射强度带来了重要影响）。 TTL在几种方面也是研究卷云及其与环境的相互作用的理想选择热带优点：该项目的见解将有助于改善一般流通模型的参数化，从而改善气候预测。Broader的影响：该项目将有助于减少气候预测中的不确定性，从而为决策者提供更准确的对未来气候的信息。该项目将为指定的博士后研究人员提供良好的声誉和研究生，从而培训下一代云建模专家。此外，PI将积极促进普林斯顿大学的本科生（以大三和高级论文的形式）参与，从而为一群经常跟随行业，金融和政府职业的学生提供第一手经验，并更好地了解气候科学。

项目成果

Mechanism of Fast Atmospheric Energetic Equilibration Following Radiative Forcing by CO 2

CO 2 辐射强迫后的快速大气能量平衡机制

• DOI: 10.1002/2017ms001116
• 发表时间: 2017
• 期刊: Journal of Advances in Modeling Earth Systems
• 影响因子: 6.8
• 作者: Dinh, T.;Fueglistaler, S.
• 通讯作者: Fueglistaler, S.