Evaluation of Ice Nuclei Generator Systems

Abstract

ARTIFICIAL ice nuclei, generated by combustion of acetone solutions of silver iodide¹, have been used in cloud seeding programmes since the early 1950s, with variable, and sometimes disappointing, results. It is apparent that the ice nuclei disseminated in many field projects have been complexes, or intimate mixtures, of silver iodide and the alkali iodides, their hydrates and decomposition products, rather than silver iodide. Although the basic evidence has been available in the published literature, the possibility that such complexes could function as ice nuclei in a different manner than would uncomplexed silver iodide has been either not understood or largely ignored.