Interrelation between variations of condensation nuclei concentration and cloud spectrum

Abstract

The characteristics are studied of warm cloud mediums (size spectra, concentration, etc.) formed in the cloud chamber of the volume of 3200 m 3 at adiabatic expansion of the humid air and at the variations of condensation nuclei concentration within the limits of 50-500 times from the initial one. To remove the nuclei, the volume electrostatic technique was used not requiring the ventilators. By means of the decrease in the cloud condensation nuclei concentration to the order of 100 cm -3 and less, it was succeeded for the first time to prevent the formation of clouds and fogs at adiabatic cooling of the humid air with equivalent speed of less than U z = 28 cm/s. At U z = 28-35 cm/s and nuclei concentration of 50-200 cm -3 , it becomes possible to simulate the fine-droplet hazes and fogs with monomodal spectra at average droplet diameter of 4-6 mm. At small and moderate rate U z = 11-100 cm/s and active nuclei concentration of 300-700 cm -3 , one can simulate the convective clouds with wide polymodal spectra. The potential of modern models of cloud spectra formation and the prospects of application of the technique of ion-stimulated variations of condensation nuclei concentration are discussed.