Variability of the supersaturation in cumulus clouds

Abstract

The supersaturation values in 147 cloud regions averaged near 0%, with standard deviations in the (10-m average) supersaturation values that ranged from 0.1% in unmixed regions to about 0.4% in regions about 80% diluted by entrainment. The Lagrangian characteristic times for supersaturation were estimated to be about 50 s for mixed regions but substantially larger for some regions with strong updrafts. The observed variability in supersaturation is comparable to that needed to account for typical dispersions in droplet size spectra. -from Authors