Quantifying Radiation Belt Electron Precipitation and Its Effect on Atmosphereand Ionosphere

In this study, we quantify the radiation belt electron loss through precipitation into the atmosphere, and simulate the electron impact on atmospheric composition and ionospheric conductance. While the influence of auroral electrons on the atmosphere and ionosphere have been studied extensively, the radiation belt electrons' contribution is not well known. This work combines measurements from Van Allen Probes near the equator and FIREBIRD CubeSat at low-Earth orbit during conjunctions, to estimate the precipitation flux and energy spectrum of radiation belt electrons in energies between 200 keV and 1 MeV. The electron flux within the loss cone is highly variable and the precipitation could change the atmospheric composition and ionospheric conductance at 50 - 120 km. To quantify the contribution of radiation belt electrons to the atmosphere, we use a global climate simulation (WACCM) to calculate the production of HOx and NOx, and the reduction in O3. Then, we calculate the ionospheric conductance caused by radiation belt electrons using a comprehensive ionosphere-thermosphere model (TIE-GCM) and a climate simulation with thermosphere and ionosphere extension (WACCM-X). The preliminary WACCM result shows a substantial reduction of O3 (30%) at 70 km caused by a moderate radiation belt electron precipitation event.