long postponement~ day for the mission have occumed before a suitable would have arrived* (b) The wimi conditionsin the Marshall Islscds have a complex structure which tends to ccwplicate the radiologicalsafety pattern. Winds blow fzwn the east fmm . the surface to near 20,000 feet, then shift to the west above this level to heights of 50 or 60,000 feet, end then agaim blow fmm atratoephere. This an easterly direction complex in the upper wind structure,when interpretedinto diffusion of radioactive debfis, requires a readiness for evacuation of personnel by Navy ships for evexy test. (c) l%ere are no known satisfactorymethodologiesfor forecastingin tropical areas. The nature of atmoepherlc prwceeses is Incompletely understood and as a result, the prediction of winds, clouds ad accccplishedwith a reldable rain cannot be accuracy. Further, becaue of the paucity of existing weather stations in the Marshall Ishnds, an undertaking of an atomic bomb experiment in this area requires the support of a very sizeable meteorological force. The existing weather stations require augmentationby pereonml and specializedequipment for making very high level ataoepheric soudings. !lewstations have to be established generalQ on un- inhabited atolls. For the SANDSTONX Operation, approximatelythree SECTION XXI 67