Parameterization of the cloud droplet–sulfate relationship

Cloud droplet number and cloud-water sulfate ion concentration data were compiled from several in-cloud studies at elevated marine and continental sites. Log–log relationships between droplet concentration and clear air equivalent non-sea-salt sulfate (NSS) concentration in the droplets were derived. The slope of the clear air equivalent (CAE) NSS concentration–droplet number concentration relationship presented here is higher than those determined in most previous studies and the relationship is log–log-linear over a wide range of CAE sulfate concentrations.