Author(s)

S. Shiba, Y. Hirata & S. Yagi

Abstract

A new model has been developed to estimate the equilibrium cloud droplet size, temperature and saturation ratio precisely based on physicochemical consideration, taking account of the variations of the water vapor content and the temperature in the air parcel. The variations are not considered in the traditional K¨ohler model. The numerical simulations with the new model reveal that the equilibrium droplet size varies considerably, depending upon both the number density of cloud condensation nuclei (CCN) and the initial saturation ratio. Although the temperature variation is too small to affect the droplet size, it is large enough to bring about the statical instability in the atmospheric boundary layer. Keywords:

Keywords