American Meteorological Society, Journal of the Atmospheric Sciences, 12(78), p. 3909-3924, 2021
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AbstractThis study employed a parallel-plate capacitor model by which the electrostatic energy of lightning flashes could be estimated by considering only their physical dimensions and breakdown electric fields in two simulated storms. The capacitor model has previously been used to approximate total storm electrostatic energy but is modified here to use the geometry of individual lightning flashes to mimic the local charge configuration where flashes were initiated. The energy discharged may then be diagnosed without context of a storm’s entire charge structure. The capacitor model was evaluated using simulated flashes from two storms modeled by the National Severe Storms Laboratory’s Collaborative Model for Multiscale Atmospheric Simulation (COMMAS). Initial capacitor model estimates followed the temporal evolution of the flash discharge energy of COMMAS for each storm but demonstrated the need to account for an adjustment factor μc to represent the fraction of energy a flash dissipates, as this model assumes the entire preflash energy is discharged by a flash. Individual values of μc were obtained simply by using the ratio of the COMMAS flash to capacitor energy. Median values were selected to represent the flash populations for each storm, and were in range of . Application of aligned the magnitudes of the capacitor model discharge energy estimates to those of COMMAS and to those estimated in previous studies. Therefore, by considering a μc within range of , application of the capacitor model for observed lightning datasets is suggested.