WtHH?’r’ The Ohief of the U. S. Weather Bureau provided the services of Pad & Humphrey, %3, who vae ordered to t~ortiy duty with the Air Forces for further ~ssignment to the meteorologicalstaff of J!l!I-7.Mr. Bumphrey, formerly, Lieute~t WHR, ~ served w assist~t staff SerologicalOff- icer for Operation CROSSROADS. He provided liaieon with the U. S. Weather Bureau where, in collaborationwith the Air Force, initial cllmatic studies of wind, weather end air trajectorieswere prep~ed and ueed for operational Plming purposes. A scieutfficprogram vae plamned and included documentationof all meteorologicalreports, observationson the rate of rise and height of the atomic cloud, volume of the cloud, microbarographobservationsIM order to obtain preliminary estimates of the bomb energy, energy estimates of the bomb from thermodynamicconsiderations,cloud trajectorycalculation, atmospheric turbulent diffision,