Development of Efficient Models of Streamer to Leader Transition in the Earth's Atmosphere

This grant will allow research to continue on streamer-to-spark modeling, with a main goal of developing an efficient and accurate air heating model to study streamer-to-leader transition in lightning and air heating processes in transient luminous events (TLEs). New observations of events like gigantic jets and space leaders in lightning show the need for the development of streamer-to-leader transition models capable of simulating leader formation and propagation in a broader range of values of leader electrical current and ambient air pressure. The research aims of the award are to answer questions about: the scaling of streamer-to-leader transition with pressure, parameterization of channel decay time, polarity asymmetries in positive and negative leader formation and propagation, possibility of air heating in sprites, and long persistency of bead structures in sprites.

The broader impacts of the research include the education and training of a graduate student and the inclusion of undergraduate students in the research through direct funding and the association with an existing Research Experiences for Undergradutes program. Models developed during the award period would be made available to the community.