A particle’s surface is treated as a continuum of ice nucleation sites with a Gaussian distribution of freezing ability to predict particle-induced freezing of cloud droplets. This does not require prescribing the size or number of active sites. Analysis of droplet freezing data revealed a critical total surface area threshold, above which the variability of active site ability saturates. Below this threshold an apparently higher ice active site density (ns) is retrieved for the same system.
