Low Frequency Variability in the Extratropical Atmosphere

该奖项为Robinson博士对温带大气低频变率的持续研究提供了支持，该研究采用了观测分析、环流模式输出分析和简单数值模式的混合分析。首席研究员将专注于三项任务。第一个是发展和应用一种广义正压模式，用于低频变率的诊断和过程研究，无论是观测到的还是一般环流模式（GCMs）。这是PI的一项新工作，涉及一种新的创造性方法，该方法采用PI的经验推导出的势涡和流函数之间关系的公式。另外两个任务是以前支持的工作的延续。一是对控制全球环流输出和观测中的纬向指数的动力学以及纬向指数的可预测性进行一系列诊断性研究。另一个主要领域涉及对纬向不对称基本态的正压不稳定性的非线性行为的分析研究，这种不稳定性被认为是造成大气低频变率的原因。所有这些研究对于提高对大气动力学过程的理解是重要的，这对改进扩展范围预测是至关重要的。＊＊＊

9628850 Robinson This award provides support for Dr. Robinson's continuing research on the low frequency variability of the extratropical atmosphere and employs a mix of observational analyses, analyses of general circulation model output, and simple numerical models. The principal investigator will focus on three tasks. The first is the development and application of a generalized barotropic model to be used for diagnostic and process studies of low frequency variability, both observed and in general circulation models (GCMs). This is a new undertaking by the PI and involves a new, creative approach that employs the PI's empirically derived formulation of the relationship between potential vorticity and the streamfunction. The other two tasks represent continuations of previously supported work. One is a series of diagnostic studies of the dynamics governing the zonal index in GCM output and in observations, and of the predictability of the zonal index. The other major area involves analytical studies of the nonlinear behavior of the barotropic instability of zonally asymmetric basic states which is believed to contribute to the low frequency variability in the atmosphere. All of these studies are important for advancing understanding of atmospheric dynamic processes that are critical to improved extended range prediction. ***