(1988)
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In their theoretical characterization of cloud microphysics of the giant planets, Carlson et al. (1988) employ the formalism of Rossow (1978) to calculate time constants for droplet condensation within cloudy updrafts (assuming a supersaturation of 10$^{-3}$), droplet coalescence (assuming the mean collision rate is described by particles with a mass ratio of 2), and sedimentation through an atmospheric scale height. From these time constants, estimates are made of the predominant size of cloud particles at cloud base for a number of condensates. For the Jovian ammonia cloud, Carlson et al. estimate a mass-weighted droplet radius of $\sim 10 - 30 \: \mu$m.

Carlson et al. (1988) make no attempt to calculate vertical profiles of condensate mass. For profiles of vapors that condense into multiple forms (such as ammonia, which can also condense onto a cloud of NH$_4$SH below the ammonia cloud), saturation is assumed above the cloud base.

A shortcoming to the approach of Carlson et al. (1988) is that their microphysical time constants strongly depend on a number of uncertain factors, chief among them completely unknown supersaturations, which govern droplet growth rates due to condensation. Supersaturations in a cloudy updraft are determined by balance between the source 