Optical and Electromagnetic Investigations of Cloud-to-Ground Lightning in the Context of In-Cloud Discharge Processes

云内放电过程中云地闪电的光学和电磁研究

• 批准号: 0721119
• 负责人: William Beasley
• 金额: $ 40.37万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-06-15 至 2012-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0721119&HistoricalAwards=false
• 关键词: Optical; Electromagnetic; Investigations; Cloud; Ground

This project will establish a new program of close-range optical and electromagnetic observations of cloud-to-ground (CG) lightning, to be obtained simultaneously with longer-range observations of entire in-cloud discharge processes that occur before, during, and after CG flashes. The primary scientific goal is to determine how various characteristics of the CG component of lightning flashes, observed with high time resolution, relate to the entire in-cloud discharge process. To accomplish this goal, a cost-effective long-term observing capability will be established in the observatory at the new National Weather Center Building on the campus of the University of Oklahoma in Norman, OK. Cloud-to-ground flashes will be observed by means of a streak-film camera, a photodiode array, and broadband electric-field-change ("slow" and "fast") antennas. The work will take advantage of several existing operational facilities for lightning and severe-storm research in central Oklahoma. These include the Oklahoma Lightning Mapping Array, and existing optical observing systems on loan from the University of Florida. In addition, there will be collaboration with colleagues at the Los Alamos National Laboratory. They operate the Los Alamos Sferics Array, an extended research-grade lightning location and characterization system that covers central Oklahoma, and the FORTE satellite, with optical lightning detectors on board, which periodically passes over the region.The establishment of this unique long-term observing capability will provide an unprecedented opportunity to study lightning in a variety of storms in all seasons over a relatively long period of time. This program of research will document and enhance quantitative understanding of CG lightning flashes by providing new detailed and coordinated observations of various features of flashes that have been reported anecdotally and qualitatively by previous lightning observers. In the future, whenever observational thunderstorm field campaigns are undertaken in central Oklahoma, high-quality optical and electromagnetic CG lightning observations will be possible at little additional cost to these future programs. Finally, the project will take advantage of ongoing National Weather Center outreach and education programs to engage in mentorship of undergraduate and high-school students, with a special effort to involve Native American students.

该项目将建立一个新的云对地（CG）闪电的近距离光学和电磁观测计划，与CG闪电之前，期间和之后发生的整个云内放电过程的长距离观测同时获得。 主要的科学目标是确定以高时间分辨率观测到的闪电CG分量的各种特征与整个云内放电过程的关系。 为了实现这一目标，将在俄克拉荷马州诺曼市俄克拉荷马州大学校园内新的国家气象中心大楼的观测站建立具有成本效益的长期观测能力。 云对地闪光将通过条纹胶片照相机、光电二极管阵列和宽带电场变化（“慢”和“快”）天线来观测。 这项工作将利用俄克拉荷马州中部现有的几个闪电和严重风暴研究设施。 其中包括俄克拉荷马州闪电测绘阵列，以及从佛罗里达大学借来的现有光学观测系统。 此外，还将与洛斯阿拉莫斯国家实验室的同事合作。 他们操作着洛斯阿拉莫斯天电阵列，这是一个覆盖俄克拉荷马州中部的扩展的研究级闪电定位和定性系统，还操作着载有光学闪电探测器的FORTE卫星，该卫星定期经过该地区，这种独特的长期观测能力的建立将提供一个前所未有的机会，在一个相对较长的时期内研究所有季节各种风暴中的闪电。 该研究计划将通过提供对以前闪电观察员报告的轶事和定性的闪电的各种特征的新的详细和协调的观察来记录和增强对CG闪电的定量理解。 在未来，每当观测雷暴场运动进行中俄克拉荷马州，高质量的光学和电磁CG闪电观测将有可能在这些未来的计划很少的额外费用。最后，该项目将利用正在进行的国家气象中心外展和教育计划，为本科生和高中生提供指导，并特别努力让美洲原住民学生参与其中。