Electrification and Lightning in Convective and Mesoscale Precipitation

对流和中尺度降水中的带电和闪电

• 批准号: 1010657
• 负责人: Steven Rutledge
• 金额: $ 70.21万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1010657&HistoricalAwards=false
• 关键词: Electrification; Lightning; Convective; Mesoscale; Precipitation

This award will allow the research team an opportunity to expand on their investigations into atmospheric convection, cloud electrification, and lightning. The three main areas of work are (1) the statistical analysis of regional differences in storm structure and lightning and their potential relationships to environmental parameters and aerosols, (2) the relationship between mesoscale precipitation systems and transient luminous events (TLEs), and (3) the meteorology surrounding large impulse charge moment changes (iCMCs). In order to perform the statistical analyses required, the research group will use a recently developed algorithm that ingests and synthesizes radar, lightning, environmental, and aerosol data. The algorithm would be used with selected data sets to run basic statistical tests on different parameter populations in order to answer questions about the relationships of lightning with convective structure, the meteorological environment, and aerosols. For the second task, the group will analyze a number of case studies of TLE-producing events and compare them to prior case studies to address hypotheses relating to the production of TLEs in mesoscale convective systems (MCSs). They will focus on the stratiform charge layer, embedded convection in stratiform precipitation, and regional differences in MCS structure. For the third task, the researchers will study iCMCs, which are the products of the charge magnitude lowered to ground and the height above ground from which the charge is lowered, over the first 2 ms of a cloud-to-ground lightning strike. iCMCs can be measured by a recently developed instrument, and the researchers will use the observational data to place large iCMC observations in meteorological context to see what types of weather situations may produce these large charge moment changes.The intellectual merit of the work includes the improved understanding of the relationships between storm structure and lightning behavior, and the influence of the environment on convection and lightning. Both topics will be enhanced by a greater amount of data, larger geographic reach, and additional instrumentation available for this work. The research will also help to improve knowledge about the connections between MCSs and TLEs and determine what information iCMC events can tell us.The broader impacts of the research include the involvement of multiple graduate and undergraduate students and citizen scientists, widespread dissemination of results and data, and better understanding of high-impact convection and lightning.

这一奖项将使研究小组有机会扩大他们对大气对流、云带电和闪电的研究。工作的三个主要领域是(1)风暴结构和闪电的区域差异及其与环境参数和气溶胶的潜在关系的统计分析；(2)中尺度降水系统与瞬变发光事件(TLE)的关系；(3)围绕大冲量电荷矩变化(IMMC)的气象学。为了执行所需的统计分析，研究小组将使用最近开发的一种算法，该算法可以摄取和合成雷达、闪电、环境和气溶胶数据。该算法将与选定的数据集一起用于对不同参数总体进行基本统计检验，以回答有关闪电与对流结构、气象环境和气溶胶的关系的问题。对于第二项任务，该小组将分析一些TLE产生事件的案例研究，并将它们与先前的案例研究进行比较，以解决与中尺度对流系统(MCSs)中TLE产生有关的假设。他们将关注层状电荷层、层状降水中的对流以及MCS结构的区域差异。对于第三项任务，研究人员将研究iCMCs，这是在云对地闪电袭击的前2毫秒内，降低到地面的电荷量和电荷从地面上降低的高度的乘积。最近开发的一种仪器可以测量iCMCs，研究人员将使用观测数据将ICMC的大型观测放在气象背景下，看看什么类型的天气情况可能会产生这些大电荷时刻变化。这项工作的智力价值包括更好地理解风暴结构和闪电行为之间的关系，以及环境对对流和闪电的影响。这两个主题都将通过更多的数据、更大的地理范围和这项工作可用的额外工具来增强。这项研究还将有助于提高对MCS和TLE之间联系的了解，并确定ICMC事件可以告诉我们什么信息。研究的更广泛影响包括多个研究生和本科生以及公民科学家的参与，结果和数据的广泛传播，以及对高冲击对流和闪电的更好理解。