Characterization of Lighting which Produces Mesospheric Transient Luminous Events (Sprites and Elves)

Fma Research, Inc., Fort Collins CO

Investigators

Abstract

Transient luminous events (TLEs) such as red sprites, blue jets, and elves are newly discovered phenomena that link tropospheric electrical activity with the stratosphere and mesosphere. These phenomena are almost always associated with positive cloud-to-ground lightning, which occurs less frequently than negatively charged lightning. Two major storm types are known to produce positive lightning, namely supercell storms and nocturnal mesoscale convective systems. The STEPS project (SevereThunderstorm Electrification and Precipitation Study), conducted in western Kansas in the early summer of 2000, will provide extensive information on these storm types, including dual-Doppler and polarimetric radar observations, aircraft microphysical measurements, high-resolution lightning maps, and balloon-borne measurements of the electrical field. This research project contributes to STEPS by documenting and characterizing TLEs above the storms using optical, acoustical, and radio methods. The goal is to determine the physical differences between storms that produce TLEs and those that do not. The data will also be used to determine to what extent Schumann resonance measurements at sites far away can detect sprites and elves.