Atmospheric Electricity Induced In-Cloud Scavenging Changes: New Parameterizations of Electro-Scavenging and Electro-Anti-Scavenging

Effects of electric charge on rate coefficients for scavenging of aerosol particles, which can act as cloud condensation nuclei and ice-forming nuclei, are obtained by trajectory simulations, for nuclei of radii 0.004 microns to 2 microns in collisions with droplets of radii 6 microns and 15 microns. The simulations include weight, intercept effect, phoretic forces and diffusion along with the forces due to typical electric charges on droplets and nuclei. Time scales for depletion of the large CCN by increases in the scavenging rates are evaluated, together with the reduction of the loss of small CCN (otherwise due to phoretic and diffusive scavenging). Effects on contact ice nucleation are also evaluated.