Scales and Characteristics of Convective Processes in Orographic Precipitation

地形降水对流过程的规模和特征

• 批准号: 0121963
• 负责人: Sandra Yuter
• 金额: $ 40.44万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0121963&HistoricalAwards=false
• 关键词: Scales; Characteristics; Convective; Processes; Orographic

Orographic precipitation is important both economically and from a public safety (flash flooding) standpoint. In this research, the Principal Investigator will investigate the physical processes that control orographic precipitation. Four questions to be addressed:1. What are the relative contributions of coalescence and riming to accretional growth of precipitation in storms that extend several km above the freezing level?2. Is there a significant difference in precipitation growth due to coalescence between storms that do and do not extend above the freezing level?3. What is the size distribution of and spacing between precipitating convective elements that contribute to the observed small-scale variability of precipitation?4. Is there a significant difference in the characteristics of the raindrop size distribution within fallstreaks and between fallstreaks?The study will be observationally based and will utilize data collected from two completed field programs - the Mesoscale Alpine Programme and the Pacific Landfalling Jets Experiment. The answers to the above questions will contribute to improvement of parameterized and explicit descriptions of cloud microphysics within numerical models of orographic precipitation and to better characterization of sampling and beam filling errors for satellite remote sensing applications.

从经济和公共安全（山洪暴发）的角度来看，地形降水都很重要。在这项研究中，首席研究员将调查控制地形降水的物理过程。需要解决的四个问题：1。在冰点以上延伸数公里的风暴中，聚结和环结对降水的增加增长有什么相对贡献？在降水增长方面是否存在显著的差异，这是由于在冰点以上和不在冰点以上延伸的风暴之间的合并造成的？对观测到的降水小尺度变率有贡献的降水对流要素的大小分布和间距是什么？雨点大小分布的特征在雨点内和雨点之间是否有显著差异？该研究将以观测为基础，并将利用从两个已完成的实地项目收集的数据-中尺度高山项目和太平洋降落喷气机实验。上述问题的答案将有助于改进地形降水数值模式中云微物理的参数化和明确描述，并有助于更好地表征卫星遥感应用的采样和波束填充误差。