Timescales for physical processes controlling cloud particle distribution in the atmosphere. For monodisperse distributions, the timescales of collisions are shown for the three driving processes considered: gravitational settling (green), Brownian motion (red), and turbulence (blue). Also shown are the timescales of the other microphysical processes: gravitational settling (τ_sett, cyan), condensational growth (τ_grow, magenta), nucleation (τ_nucl, gold), and mixing (τ_mix, brown). Effective temperatures from top to bottom are T_eff = 2400, 2000, 1800, 1600, 1400 K. Two surface gravities are shown: log₁₀(_g[cm s−²]) = 3.0 (left) and log₁₀(g [cm s⁻²]) = 5.0 (rieht).