Thunderstorm Intensity & Gamma-ray Emission: A GOES ABI and GLM Analysis of the 2023 ALOFT Campaign

Bursts of gamma radiation observed in growing thunderstorm cells during the Airborne Lightning Observatory for the Fly’s Eye Geostationary Lightning Mapper Simulator and Terrestrial Gamma-ray Flashes (ALOFT) campaign led the team’s forecasters and mission scientists to direct the research aircraft toward storms that had rising lightning flash rates, informed by real-time Geostationary Lightning Mapper (GLM) products such as the NASA SPoRT Lightning Viewer. The production mechanisms and thunderstorm morphology that result in terrestrial gamma-ray flashes (TGFs), which are on the order of tens of megaelectronvolts and hundreds of microseconds to a few milliseconds, is an area of ongoing research. Previous work found that TGFs occur preferentially when lightning flash rates are instead locally falling, and flash amplitudes and areas are higher. Herein we present an analysis of the 12 flights, summing 130 transient events including TGFs, gamma-ray glows on the order of hundreds of seconds, and flickering gamma-ray flashes which are a series of pulses each on the order of hundreds of seconds. Utilizing the Geostationary Operational Environmental Satellites (GOES) Advanced Baseline Imager (ABI) and GLM, time series of the thunderstorms’ evolution through flash rate, flash area, brightness temperature, and extent of cold cloud tops are evaluated in tandem with the incidence of gamma radiation measured by the University of Bergen Bismuth Germanite detector, to further the understanding of its relationship with electrification and intensification processes.