Short-Range Ensemble Forecasting of Quantitative Precipitation

定量降水的短程集合预报

• 批准号: 9612487
• 负责人: Steven Mullen
• 金额: $ 25万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-15 至 2001-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9612487&HistoricalAwards=false
• 关键词: Short; Range; Ensemble; Forecasting; Quantitative

9612487 Mullen The U.S. Weather Research Program (USWRP) is an interagency activity designed to perform and implement the research necessary to improve the delivery of weather services to the nation. Under this Program, the National Science Foundation and the National Oceanic and Atmospheric Administration are jointly evaluating and supporting research of high priority to the USWRP. It is well known that the atmosphere is a chaotic system. As a consequence, small errors in the initial conditions of any numerical weather prediction model amplify as the forecast evolves. Because the atmospheric state can never be measured exactly, initial conditions will always contain errors whose magnitude and structure can only be estimated. Hence an infinite spectrum of plausible initial conditions exists, all of which are consistent with analysis uncertainty. A procedure for defining the scope of forecasting uncertainty and improving forecasts is known as ensemble forecasting (EF). EF involves running multiple forecasts starting at the same time, but from different, equally-likely initial conditions. The Principal Investigator will address four fundamental aspects of short-range EF of quantitative precipitation forecasting (QPF) at the mesoscale: Estimate limits of predictability for QPF by current operational forecast models; Investigate minimum number of ensembles needed to robustly estimate forecast evolution of probability density function of QPF; For QPF forecasts, determine relative importance of model differences verses uncertainties in initial conditions; Determine the relative merit of using short range ensemble forecast at a lower resolution verses a single, high resolution deterministic forecast. The Principal Investigator will collaborate in this effort with scientists within the National Oceanic and Atmospheric Administration. Successful completion of this research could lead to substantial improvements in abili ty to forecast precipitation. ***

9612487 Mullen美国天气研究计划（USWRP）是一项跨部门活动，旨在执行和实施必要的研究，以改善向国家提供的天气服务。根据该计划，美国国家科学基金会和国家海洋和大气管理局将共同评估和支持USWRP的高优先级研究。众所周知，大气是一个混沌系统。因此，任何数值天气预报模式在初始条件下的小误差都会随着预报的发展而扩大。由于大气状态永远无法精确测量，初始条件总是包含误差，其大小和结构只能估计。因此，存在无限谱似是而非的初始条件，它们都与分析不确定性相一致。定义预报不确定性范围和改进预报的程序称为集合预报。EF包括同时运行多个预测，但从不同的、相同可能的初始条件开始。首席研究员将讨论中尺度定量降水预报（QPF）的短期EF的四个基本方面：当前业务预报模式对QPF可预测性的估计极限；研究了稳健估计QPF概率密度函数预测演化所需的最小集合数；对于QPF预测，确定模型差异与初始条件下不确定性的相对重要性；确定较低分辨率的短期集合预报与单一的高分辨率确定性预报的相对优点。首席研究员将在这项工作中与国家海洋和大气管理局的科学家合作。这项研究的成功完成将大大提高预报降水的能力。＊＊＊