weather modification, particularly hostile weather warfare, was addressed by the "united nations general assembly resolution 31/72, tias 9614 convention on the prohibition of military or any other hostile use of environmental modification techniques." the convention was signed in geneva on may 18, 1977; entered into force on october 5, 1978; ratified by u.s. president jimmy carter on december 13, 1979; and the u.s. ratification deposited at new york january 17, 1980.