Secondary Circulations on the Potential Vorticity Staircase: A Theory of Atmospheric Transport

位涡阶梯上的二次环流：大气输送理论

• 批准号: 1333029
• 负责人: Richard Scott
• 金额: $ 61.16万
• 依托单位: NorthWest Research Associates, Incorporated
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-12-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1333029&HistoricalAwards=false
• 关键词: Secondary; Circulations; Potential; Vorticity; Staircase

The goal of this project is to examine interactions between two fundamental and distinct types of atmospheric circulation: primary circulations, consisting of zonal, east-west directed jets together with their embedded Rossby waves and Rossby-wave critical layers; and the slower but persistent secondary circulations, which are driven to a large extent by the eddy mixing associated with the jets and waves of the primary circulations, and which control long-term meridional transport throughout the atmosphere. Although primary circulations drive secondary ones, the latter also modify the former though the transport both of momentum and of radiatively active chemical species, notably carbon dioxide, water vapor, and ozone. The work builds extensively on previous NSF-supported research on the "potential vorticity staircase" and the nature of atmospheric zonal jets. A key theme will involve a consideration of the influence of inhomogeneous eddy mixing on the distribution of secondary circulations in height and latitude; and, in turn, the steepening of chemical tracer and potential vorticity gradients by the differential vertical motions of the secondary circulations. Theoretical investigations into the importance of non-trivial vertical structure and the role of eddy-driven secondary circulations in the potential vorticity staircase will be complemented by applications to topical issues in stratosphere-troposphere and tropical-polar dynamical coupling and the transport of chemical tracers throughout the atmosphere.

该项目的目的是检查两种基本和不同类型的大气循环之间的相互作用：主要的循环，由Zonal，East Witch的指向喷气机组成，以及它们的嵌入式Rossby Wave和Rossby-Wave临界层；以及较慢但持续的二次循环，这些循环在很大程度上由与主要循环的喷气机和波浪相关的涡流混合，并控制整个大气中的长期子午运输。尽管主要循环驱动了次要循环，但后者也可以修改前者，但既有动量和辐射活性化学物种的运输，尤其是二氧化碳，水蒸气和臭氧。这项工作广泛建立在先前关于“潜在涡度楼梯”和大气区域喷气机的性质的研究基础上。一个关键主题将涉及考虑不均匀涡流混合对高度和纬度次级循环的影响的影响；然后，通过二级循环的差异垂直运动，化学示踪剂和潜在的涡度梯度陡峭。对非平凡垂直结构的重要性以及涡流二次循环在潜在的涡度楼梯中的作用的理论研究将得到对局部问题的应用以及在整个大气层整个大气层中的局部问题和热带极性动力学耦合以及化学示踪剂的运输。