Initial Value Problem Theory of Cyclogenesis and the Predictability of Flows

循环发生的初值问题理论和流动的可预测性

• 批准号: 8912432
• 负责人: Brian Farrell
• 金额: $ 27.42万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-15 至 1992-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8912432&HistoricalAwards=false
• 关键词: Initial; Value; Problem; Theory; Cyclogenesis

The overall goal of this project is to better understand the development of synoptic scale weather systems, which may ultimately lead to improved weather forecasts. The principal investigator's previous work has focused how the structure of the flow, or "initial value", contributes to subsequent development of perturbations. He will extend this research along two lines. The first thrust is to continue his investigations into the physical mechanism(s) responsible for cyclogenesis; the other is to explore the predictability of large scale atmospheric flows. Observational evidence suggests that deformation, as well as shear, in the background atmospheric flow plays an important role for certain types of cyclogenesis. The principal investigator already has shown the effect of shear in the background flow on the energetic development of cyclones. He will extend this work to look at the effect of confluence and difluence on perturbations in the flow. While the subject has been studied extensively, theoretical estimates of the predictability of the atmosphere still vary widely as do the results from numerical weather prediction experiments. The reason appears to be variability in the predictability of the flow regimes, that is, certain types of flows are inherently more predictable than others. The principal investigator will explore the growth of error in numerical models and attempt to distinguish between those flows which are predictable and those which are not as a function of flow characteristics.

该项目的总体目标是更好地了解天气尺度天气系统的发展，这最终可能导致天气预报的改进。 首席研究员之前的工作重点是流动结构或“初始值”如何促进扰动的后续发展。 他将沿着两条线扩展这项研究。 第一个目标是继续研究气旋发生的物理机制； 另一个是探索大尺度大气流动的可预测性。 观测证据表明，背景大气流中的变形和剪切对于某些类型的气旋发生起着重要作用。 主要研究者已经展示了背景流中的剪切力对气旋能量发展的影响。 他将扩展这项工作，以研究汇合和分流对流动扰动的影响。 尽管这一主题已得到广泛研究，但大气可预测性的理论估计仍然存在很大差异，数值天气预报实验的结果也是如此。 原因似乎是流态可预测性的可变性，即某些类型的流本质上比其他类型的流更可预测。 首席研究员将探索数值模型中误差的增长，并尝试区分可预测的流量和不可预测的流量特征。