I. GENERAL A. In September 1952 a preliminary report was prepared on this subject. When the preliminary study was made there was considerable doubt whether the cloud from thermonuclear weapons could pierce the tropopause and rise significantly against the isothermal or inversion lapse rate of the stratosphere. Since practically all of the mushroom of the IVY-MIKE shot penetrated the tropopause and the maximum height reached was 134,000 ft. msl for the plume anc 125,000 ft. for the top of the mushroom, there is no longer any doubt that man made explosions can carry aloft to the required heights a considerable quantity of soil debris. The preliminary report used the Rayleigh equations for diffuse reflection and random scatter of radiation by dust particles, Upon further analysis of the problem it is,now realized that since a majority of the dust particles under consideretion are in the size range as the wave length of visible light, the simple inverse fourth power of the wave length function developec by Rayleigh for radiation scatter must be discarded for the more complete theory developed by Mie (5). In the preliminary report the amount of dust required aloft was divided by the fourth power of the ratio of the wave lengths of terrestrial to solar radiation. It is now realized that such a procedure was not justified. Much of the data contained in the preliminary report will be included in this second study. This may be repetitious, but it will have the advantage of putting the required information in one report. B. From a study of the reddish-brown corona observed around the sun for two or three years after the volcanic eruptions of Krakatoa in 1883, Mont Pelee and Santa Maria in 1902 and Katmai in 1912, astronomers observed ‘a significant reduction in solar radiation (10 to 297) due to a dust layer aloft. Humphreys (1) calculated that if 1.734 x 10“* spherical particles of 1.85 micron diameter are uniformly distributed throughout the isothermal region of the etmosphere, there would be a significant reduction in solar radiation. If this is continued over ae period of time, the surface temperature of the earth would be reduced by several degrees centigrade and this would lead to a general cooling of the earth's climate. Humphreys aiso maintained that if major volcanic eruptions occur once a year, or even once every two yeers over a period of time, the snow line may be depressed significantly possibly leading to a moderate ice age. Ina recent article I H. Wexler of the U. S. Weather Bureau (3) states that Humphreys volcanic Theory of Climates has considerable merit as compared to the other climatic variation theories, II, PURPOSE Determine whether it is possible for superweapons exploded on the surface or underground to eject a sufficient quantity of just into the stratosphere so ae to reduce insolation by 10% to 208. IIIT. JHE TOTAL QUANTITY OF SOJL EJ ALOFT BY SUPERWEAPONS If a simple comparison is made between the amount of material ejected ~— 500! : a9] oh — a . r ” poe » a from the major volcanoes and that from atomic bombs or even from thermonuclear bombs it is at once evident that volcanoes eject far more total —~ 6238529