Observational and Modeling Studies of the Structure and Dynamics of Jet Streaks

喷射条纹结构和动力学的观测和建模研究

• 批准号: 9818088
• 负责人: Daniel Keyser
• 金额: $ 32.18万
• 依托单位: SUNY at Albany
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9818088&HistoricalAwards=false
• 关键词: Observational; Modeling; Studies; Structure; Dynamics

Jet streaks, small areas of accelerated flow embedded in the broader rapidly moving jet streams of the upper troposphere, are associated with rapid cyclogenesis, heavy precipitation, and severe convective storms; hence, are of major interest for weather forecasting. The principal investigator, Dr. Keyser, will explore the nature of jet streaks, looking at their three-dimensional structure using observational and diagnostic analyses and employing several models - a quasi-geostrophic and primitive equation channel models. He hypothesizes that polar-front jets often result from the superposition of upper level monopolar or dipolar vortices of sub-synoptic dimensions on the large-scale jet stream. The vortices "induce" jet streaks. The investigation will focus on the three-dimensional structure of the jet streaks, along with the associated rotational and divergent ageostrophic circulations and vertical motions.

急流条纹是嵌入在对流层上部更广泛的快速移动急流中的加速流动的小区域，与快速气旋生成、强降水和强对流风暴有关；因此，对天气预报具有重要意义。首席研究员凯瑟博士将探索喷流条纹的本质，使用观测和诊断分析来观察其三维结构，并使用几种模型--准地转通道模型和原始方程通道模型。他假设，极锋急流通常是由次天气尺度的高层单极或偶极涡旋在大尺度急流上叠加而成的。涡流“诱导”喷流条纹。研究将集中在急流条纹的三维结构，以及与之相关的旋转和发散的非地转环流和垂直运动。