él. Machta, Lester METEOROLOGICAL FACTORS AFFECTING SPREAD OF RADIOACTIVITY FROM NUCLEAR BOMBS. dourne)oftheWashingtonAcadeny ofSciences &7, 169-79 - (1957). erations for local dispersement, accounted for in a day or less, are: (1) relative time of fall, as a function of altitude, used to predict downward transfer of fall- out, (2) turbulent diffusion causing significant gravie tation fallout velocity at rate of 0.1-0.01 mile/hr. of particles of specific gravity 2.5 and 50 + » diameter, and (3) precipitation usually caused by moisture entrain- ed in the fireball and condensing upon cooling. Interemediate fallout, extending a day to a month, usually originates in the troposphere and rarely penetrates the tropopause unless the fireball is from a high-yield detonation. Transversal displacement of debris is computed to be predominantly cumulative in the same latitude as characterized by the motion of atmosphere determined by air masses carried zonally or latitudinally. However, anomalous situations can spread the debris to an entirely K ee eee ete ne Bh. . Meteorological considerations accounting for atmospheric dispersal of all types of radioactive particulate debris caused by a nuclear explosion are explored on local, intermediate, and delayed dispersement phases. Consid- new and spearate area; therefore, apportionment of fallout in the intermediate stage suggests newer and more efficlent methods of determining radioactive fallout are of immediate concern. Stratospheric sampling holds the key to residence time and removal rate of radioactive debris. The distribution in time and space may allow predictions roroggter quantitative interpretation of residence time of Sr 62. Marei, A. N. EVALUATION OF SR’~ 90 AS CONTAMINATING FACTOR. Badiojogy 2, 89-95 (1957). 63. (In Russian). Medical Miyake, Y.; and Saruhashi, K. WORLD-WIDE STRONTIUM 90 DEPOSITION DURING THE PERIOD FROM 1951 TO THE FALL OF 1955. physics 8, 21-4 (1957). MeteorologyandGeo- * Miyake, Y.; Sugiura, Y.; Saruhashi, K.; and Kanazawa, T. ESTIMATION OF THE AMOUNT OF SR-90 DEPOSITION AND THE EXTERNAL INFINITE GAMMA DOSE IN JAPAN DUE TO MAN-MADE RADIOACTICITY. (1957). MeteorologyandGeophysics 9, 222-231

Select target paragraph3