The Dynamics of Weather Regime Transitions

在改进数值扩展范围天气预报的努力中，一个紧迫的问题是更好地预测持续天气制度的建立和破坏。虽然人们花了很多精力来研究这些制度的维持，但对它们的生命周期却知之甚少。首席研究员将在国家大气研究中心的社区气候模式（CCM）第2版中对天气状态转变进行全面的诊断研究。具体地说，PI将试图确定负责中纬度地区政权转变的动力和物理机制。第一个任务将是验证CCM2扩展集成中持续大尺度流动异常的统计、结构和时间演变。然后将模拟事件的特征与观测分析进行比较。使用模式“数据”可以使PI避免观测研究中固有的问题，如模式中明确知道的非保守过程和二次循环，并且在稀疏或不确定的观测中没有困难。＊＊＊

A pressing problem in efforts to improve numerical extended range weather forecasts is to better predict the establishment and breakdown of persistent weather regimes. While much effort has been devoted to studying the maintenance of these regimes, less is known about their life cycles. The principal investigator will conduct a comprehensive diagnostic study of weather regime transitions in version 2 of the Community Climate Model (CCM) of the National Center for Atmospheric Research. Specifically, the PI will attempt to identify the dynamical and physical mechanisms responsible for regime transitions in the midlatitudes. The first task will be to validate the statistics, structure and time evolution of persistent large-scale flow anomalies occurring in extended integrations of the CCM2. Characteristics of the simulated events then will be compared with observational analyses. Using model "data" allows the PI to avoid the problems inherent in observational studies as nonconservative processes and secondary circulations which are known explicitly in the model and there are no difficulties with sparse or uncertain observations. ***