Scavenging of sea-salt aerosols by rain events over Arabian Sea during ARMEX

Scavenging coefficients are obtained for sea-salt particles at rainfall intensity of 5, 10, 15, 20 and 45 mm h −1. Evolutions of size distributions for sea-salt particles by precipitation scavenging are simulated using theoretically estimated scavenging coefficients. Results indicate that below-cloud scavenging affects mainly sea-salt particles in coarse mode. Observed concentrations of Na + and Cl − in rainwater increased with rainfall intensity and aerosol size. Comparison of predicted concentrations of Na + and Cl − in rainwater with observed ionic concentrations of short-timed wet-only samples collected during rain events on 2 August 2002 over Arabian Sea (ARMEX-2002) supports the model result.