The thermodynamics of saturated air: A contribution to the classical theory

Abstract The temperature attained in the reversible and pseudo‐adiabatic expansion of air saturated with respect to liquid water is taken as a reference; the temperatures attained in the following expansions from the same initial state are then compared with it: (a) the ice‐saturation pseudo‐adiabatic process (b) the water‐saturation adiabatic process (c) the ice‐saturation adiabatic process. The results of these comparisons are summarized in Figs. 1 to 5 of this paper. Similarly, the cloud virtual temperature, the virtual temperature adjusted for the weight of suspended particles, attained in water‐saturation adiabatic expansion, is compared with that attained in water‐saturation pseudo‐adiabatic expansion; Fig. 6. The implications of these calculations for the properties and behaviour of cumulus are commented upon.