Studies of Convection and Lightning

这项研究的重点是对流的研究，特别是中尺度对流系统（MCS），这是负责在美国中部的许多地方的温暖季节降水的大部分，除了产生强降雨，他们也产生破坏性的风（包括龙卷风），冰雹和大量的闪电的形式恶劣天气。 与MCS相关的另一种类型的电活动是瞬时发光事件（TLE），被识别为精灵，精灵和蓝色喷流。 这些是发生在MCS顶部上方高空的高层大气中的放电形式，通常似乎是由云层内或云层与地面之间的闪电活动触发的。 这项工作的广泛目标是更好地了解风暴动力学，降水形成，闪电生成和TLE之间的联系。 该研究小组将进行一项大型的、基于天文学的研究，将NEXRAD和研究气象雷达数据与VHF闪电测绘阵列和国家闪电探测网络的可用数据相结合，以进一步了解雷暴中的电荷分离、雷暴中电荷层的组织、闪电和TLE放电的分布，以及这些特征如何与风暴环境的物理特征相关。 这项工作的另一个具体方面是研究弓形回波MCS的，并确定是否有更多的弓的发展和风暴云到地面闪电模式的演变之间的因果关系。 这项工作的智力价值是促进对降水发展过程、云带电和闪电的了解。这项工作的更广泛影响包括确定闪电观测如何揭示对流的物理过程，以及协助分析和预报恶劣天气特征。这项工作也是独一无二的，因为它将为未来的偏振NEXRAD雷达网络与业务闪电测绘系统相结合铺平道路，以提供更好的对流天气实时表征。

This research centers on the study of convection, specifically Mesoscale Convective Systems (MCS's), which are responsible for the bulk of the warm season precipitation in many locations in the central U.S. In addition to producing heavy rainfall, they also produce severe weather in the form of damaging winds (including tornadoes), hail and copious amounts of lightning. Another type of electrical activity associated with MCS's are Transient Luminous Events (TLE's), identified as sprites, elves, and blue jets. These are forms of electrical discharges occurring in the upper atmosphere at great heights above the tops of the MCS's that often appear to be triggered by lightning activity within the cloud, or between cloud and ground. The broad objective of this work is to better understand the linkages between storm dynamics, precipitation formation, lightning generation, and TLE's. The research team will carry out a large, statistically-based study combining NEXRAD and research weather radar data with available data from VHF lightning mapping arrays and the National Lightning Detection Network, to further understand charge separation in thunderstorms, the organization of charge layers in storms, the resulting distribution of lightning and TLE discharges, and how these characteristics may be related to the physical characteristics of the storm environment. Another specific aspect of this work is to study bow echo MCS's and determine if there is more than just a casual relationship between bow development and evolution of storm cloud-to-ground lightning patterns. The intellectual merit of this work is to advance understanding of precipitation development processes, cloud electrification and lightning. Broader impacts of this work include determining how lightning observations may reveal physical processes in convection, as well as assisting in the analysis and nowcasting of severe weather characteristics. This effort is also unique in that it will pave the way for combining the future polarimetric NEXRAD radar network with operational lightning mapping systems to provide better real-time characterization of convective weather.