Comparison of Long‐Term Lightning Activity and Inner Radiation Belt Electron Flux Perturbations. Issue 3 (7th March 2020) - Martinez‐Calderon, C.
Abstract: Lightning discharges are known to inject whistler waves into the inner magnetosphere over a wide region around their source. When a discharge occurs, it radiates electromagnetic energy into the Earth‐ionosphere waveguide, some of which couples into the whistler mode and propagates through the ionospheric plasma away from the Earth. Previous studies have discussed the effects of whistler‐induced electron precipitation and radiation belt losses associated with lightning. However, to date, there has been no research on the long‐term effects of this accumulated impact. Here, we use data from the World Wide Lightning Location Network, which has continuously monitored global lightning activity since 2004, to obtain 1 year of lightning data and categorized them into L‐shell ranges, hemispheres, and magnetic local times. We then use Van Allen Probe's Energetic Particle, Composition, and Thermal Plasma Suite from both satellites (RBSP‐A/B) to measure particle fluxes in the inner belts under the same criteria. We compare these two quantities by calculating the correlation coefficients between selected electron energy channels, including pitch angle distribution, and lightning activity under different conditions. Although we found a weak to moderate relationship between lightning activity and electron flux perturbations, the correlation was not as strong as expected from theoretical predictions. Variations in electron fluxes related to substorm activity were of the same order of magnitude as that from lightning activity, even at low L shells. Key Points: We report moderate correlation between lightning activity and electron fluxes on timescales of a few months to a year The influence of lightning activity on fluxes, even at low L shells, is of the same order as that of the AE index Seasonal variations, AE index, and MLT influence correlation between lightning activity and trapped electron fluxes