Lightning Initiation Studies

闪电引发研究

• 批准号: 1532038
• 负责人: Thomas Marshall
• 金额: $ 19.9万
• 依托单位: University of Mississippi
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1532038&HistoricalAwards=false
• 关键词: Lightning; Initiation; Studies

Despite decades of lightning research, there is still much to be learned about the initial sparks of a lightning flash and how lightning creates a path through the sky. This award will provide researchers the opportunity to set up an array of electrical sensors in northern Mississippi to collect important data that can be used to investigate and gain a better understanding of the mechanisms that start a lightning flash. Increased understanding of lightning is important due to significant societal impacts that lightning has on people and property each year. The award will also contribute to the education and training of the next generation of scientists through the support of a postdoctoral researcher and a graduate student.This award will fund the deployment of a suite of electrical sensors at nine different sites across northern Mississippi. Each site will contain an E-charge sensor, a VHF sensor, and a dE/dt sensor. In addition, the PIs will deploy two high speed video cameras, one with the ability to operate at 50,000 frames per second. The instrumentation setup is designed to allow the researchers to address the following questions: 1) What events begin and amplify an initial E-charge (IEC) and how do these events cause the IEC? 2) When and how does the transition from non-conducting air to a hot conducting channel occur? 3) What do initial breakdown pulses of intracloud flashes look like optically and are they similar to initial breakdown pulses of cloud-to-ground flashes? 4) Why do some flashes have multiple sets of IB pulses? 5) Why do some Narrow Bipolar Pulses initiate intracloud flashes while others do not?

尽管对闪电的研究已经进行了几十年，但关于闪电的初始火花以及闪电如何在天空中形成路径，仍然有很多东西需要了解。 该奖项将为研究人员提供机会，在北方密西西比建立一个电传感器阵列，以收集重要数据，这些数据可用于调查和更好地了解引发闪电的机制。 增加对闪电的了解是很重要的，因为闪电每年都会对人类和财产产生重大的社会影响。 该奖项还将通过一名博士后研究员和一名研究生的支持，为下一代科学家的教育和培训做出贡献。该奖项将资助在密西西比州北方的九个不同地点部署一套电传感器。 每个部位将包含一个电子电荷传感器、一个VHF传感器和一个dE/dt传感器。 此外，PI将部署两台高速摄像机，其中一台能够以每秒50，000帧的速度运行。 仪器设置旨在让研究人员解决以下问题：1）什么事件开始和放大初始E电荷（IEC），以及这些事件如何导致IEC？ 2)何时以及如何从非传导性空气转变为热传导通道？ 3)云内闪光的初始击穿脉冲在光学上看起来是什么样的？它们与云地闪光的初始击穿脉冲相似吗？ 4)为什么有些闪光有多组IB脉冲？ 5)为什么有些窄双极脉冲会引发云内闪光，而有些则不会？

项目成果

Groups of narrow bipolar events within thunderstorms

• DOI: 10.1016/j.atmosres.2021.105450
• 发表时间: 2021-04
• 期刊: Atmospheric Research
• 影响因子: 5.5
• 作者: S. Bandara;T. Marshall;S. Karunarathne;M. Stolzenburg

Electric field change and VHF waveforms of Positive Narrow Bipolar Events in Mississippi thunderstorms

• DOI: 10.1016/j.atmosres.2020.105000
• 发表时间: 2020-04
• 期刊: Atmospheric Research
• 影响因子: 5.5
• 作者: S. Bandara;T. Marshall;S. Karunarathne;M. Stolzenburg