Aerosol Impacts on Storm Electrification and Lightning Discharges Under Different Thermodynamic Environments

Abstract

The impacts of aerosol and thermodynamics on electrification and lightning activities have been investigated in detail using the Weather Research and Forecasting Model coupled with a double-moment microphysics parameterization and an explicit electrification lightning scheme. To obtain a varied combination of convective available potential energy (CAPE) values and aerosol concentrations, a sounding was modified consistently and initiated with five sets of aerosol concentrations that served as cloud condensation nuclei. The simulated electric processes respond to the varying dynamical and microphysical characteristics associated with the different CAPE and aerosol conditions. Under high CAPE circumstances, the augmentation of ice-phase particle leads to the enhancement of non-inductive charging primarily through the dynamic processes. Increased aerosol content further invigorates the electrification through microphysical processes. Elevated aerosol loading under low CAPE conditions increases cloud droplet and ice crystal numbers. Larger graupel particle size further leads to the enhanced electric intensity and lightning discharges.