Lightning and Thunderstorm Studies

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The five-year program of studies is a continuation of ongoing research aimed at improving our understanding of lightning discharges and discharge processes, and of the processes by which thunderstorms become highly electrified. Toward this end, a GPS-based system has been developed for mapping lightning discharges in three spatial dimensions and time, called the Lightning Mapping Array or LMA. The LMA observations show the total lightning activity in a storm and have proven to be valuable not only for scientific studies but also for meteorological applications, as an indicator of the convective strength and potential severity of storms.The research involves both scientific studies of lightning and storm electrification, and continued development and advancement of the lightning mapping observations for meteorological and related applications. The intellectual merit of the proposed research will result primarily from the scientific investigations, topics of which include further studies of storms that develop inverted-polarity electrical structures, studies of the new and different lightning types that have been found both in anomalous- and normal-polarity storms (e.g., inverted-polarity intracloud flashes, convective surge lightning, and short-duration energetic discharges), lightning initiation studies, and the use of lightning mapping observations to study the electrical structure of storms and evolution of the structure with time. The research is conducted in collaboration with other investigators using observations from already conducted field campaigns both in the Great Plains and in New Mexico, and will be expanded to include highly-detailed observations of individual lightning discharges from a compact network of closely-spaced mapping stations being set up at Langmuir Laboratory in central New Mexico. Broader impacts of the proposed activity result from further development of the lightning mapping technique as a useful technology, and the continued involvement of graduate and undergraduate students both in the scientific and applied aspects of the research. The research team works with mapping networks that have been provided to NASA in northern Alabama and to the University of Oklahoma and National Severe Storms Laboratory in central Oklahoma, and with a third network that is becoming operational at White Sands Missile Range in New Mexico. The NASA group has been supplying real-time lightning data to the National Weather Service for nowcasting applications, and the same will be done with real-time data from the Oklahoma and White Sands networks.