C OO eee SS- ce bt al ese Ie 4 \ C material into t:.e 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 were ajected from the Katmai Volcano in 1912. Some of these volcanic eruptions lasted over a period of days or weeks with variations in the intensity of explosions, There is no doubt that large volcanoes eject much more total mass into the atmosphere as compared to any man made explosion, since even megaton weapons could not eject more than a small fraction of one cubic mile of material high into the atmosphere. 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 any persistent lowering of the intensity of solar radiation reaching the surface of the earth, volcanoes must throw out high into the atmosphere (20 to 30 miles high) fine volcanie ash particles that will not settle out over a period of several years. Hence a comparison of the total mass ejected by volcanoes as compared to that ejected by Super-weapons may not be significant, It is more important to determine the heights reached by such particles, and if possible, the particle size distribution of the. dust reaching such heights. There is practically no information concerning the amount of dust that may be ejected aloft as a result of exploding superweapons on the surface or underground, According to references (8) and (8a), the cloud produced by 320,000 lbs, of TNT explosion weighed approximately 46,000 lbs. and had a yolume of 1 x 10/9 cubic feet. gives the c..ud density as 4.6 x 107° lbs/cu.ft. This However, when a particles size analysis was made, it was determined that there were very few if any particles greater than 3 microns in the cloud sampled and 40% to 70% of the particles collected were below 0.8 micron in size, This means that the 46,C00 3, weight refers to the stabilized cloud and it certainly refers to the weight of very small particles in the cloud, Actually very little reliable data exists on the pro “em and the whole method of measuring particle sizes is dependent upor and also upon the method of ana. particle size distribution during x2e methods used to collect the samples 3. For example, in studying the >eration Jangle (2) it was found that. the median particle diameter for gross samples was 0.22 micron when measured under the electron microscope whose limit of resolution is probably two orders of magnitude greater than the 0.5 micron resolving power of the optical microscope, and the median particle diameter of radioactive samples as measured by the optical microscope was 1.4 microns. Reference (8) gives the particle concentrations for the cloug from 1.0, 0.5 0.2 scale TNT shots as 2300 particles/cm?, 6700/cm? and spectively, and 2565/em re- It is assumed from this information that particle concentration in TNT explosion clouds is a function of the total amount of explosive used at scaled depths. It should be noted that 1.0 scale refers to 320,000 lbs. of TNT exploded 35 ft. underground, 0.5 scale refers to 40,000 lbs. TNT exploded 17 ft. underground and 0,2 scale refers to 2560 lbs, exploded 7 ft. underground, 500482 5 These charges and depths of explosion are scaled so that x 02-38529