On the basis of measurements accompanying a cloud-seeding experiment in western Victoria in 1979 and 1980, the conclusion is drawn that regions of supercooled water in stratiform clouds are far less prevalent than has previously been believed, and indeed are rare. The concentration of ice crystals in these clouds appears to be determined by the cloud-top temperature; this concentration is so high in clouds with temperatures colder than —18°C that there would be few opportunities for cloud seeding, even if abundant supercooled liquid water were present.
W. D. King (Mon,) studied this question.