randomly scattered and as Lord Rayleigh has shown, such scatter is proportional to the inverse fourth power of the wave length of radiation concerned (see Equation 2), Theoretically this would shut out the solar radiation approximately 332,000 times as effectively as it would shut out terrestrial radiation, since 1#/o. 54 = 3.32 x 105. The usefulness of this factor will be discussed in other parts of this report. Wexler is of the opinion that Humphreys' Volcanic Climate Theory #s the correct one because of the striking fact that since 1912 no major volcanic explosion has occurred in the Northern Hemisphere and during this period the winters have been warmer. No other theory of climate can explain this marked warming, and since this trend marched on through three full sunspot cycles, the warming cannot be attributed to changes in the sun. Wexler also points out that volcanic dust particles may reduce the "sunfall" by acting as nuclei for the formation of ice clouds. This hypothesis is based upon the recent discovery that dust particles can act as nuclei to form ice crystals in subfreezing air saturated with water vapor. Astronomers measured a maximum reduction of 20% in the radiation of the sun due to the Katmai volcanic eruption in 1912. From a study of the reddish-brown corona around the sun the diameter of the dust particles was calculated to be 1.85 micron and the total number of particles was calculated to be 1.734 x 10*4, If it is assumed that all these particles are apherical and their density is 3 gm/cm3 then total weight of these particles required aloft is 1.7 x 1013 gm. It should be noted that if the particles are 1.85 micron in diameter it would take approximately two years (1.8 years) for such particles to reach the ground from 100,000 ft. This is based upon Stokes' Law as altered by the Cunningham correction factor. -According to the latest estimates, clouds from megaton yield weapons are expected to reach heights of from 70,000 to 150,000 ft. with some people speculating on the possibility of venting the atmosphere if hundreds of megatons of yield are obtained. If the average particle size is 0.25 micron then Stokes' Law does not apply since this dust would not settle out even in one century, but dust of such small size will be subjected to Brownian motion and of course to atmospheric turbulence. It may be assumed therefore that any dust of 0.2 micron diameter in the isothermal region of the atmosphere will probably remain there except as effected by atmospheric circulation. IV. ~ EFFECT OF SUPERWBAPONS UPON THE CLIMATE OF THS wORLD: If a simple comparison is made between the amount of material ejected from the major volcanoes and that from atomic bombs (even of megaton yields) it is at onceevident that volcanoes eject far more material into the atmosphere, Although no accurate figures exist it has been variously estimated that 13 cubic miles disappeared during Krakatoa, and from 1 to 5 cubic miles of material was ejected from Katmai volcano in 1912. Some of these volcanoes lasted over a period of days or weeks with variations in the intensity of explosions. There is no doubt that large volcanoes eject mich more total mass into the atmosphere as compared to any man made explosion. However, it may be that volcanoes are not efficient in this matter, in that they waste a very large amount of their total output in the lower layers of the atmosphere. It should be noted that to produce major effects on climate the volcano must throw high into the atmosphere (100,000 ft.) fine material (average diameter of 2 microns or less) that 5004813 periods of t A 3 nortee, aetna 02222190 nl? .