A photoreconnaissance technique for conducting time-lapse studies of the development and motions of cumulus cloud populations and systems

Tests of the technique were conducted over the Florida peninsula on four days in October 1965 using a U-2 aircraft that was flown continuously in a circle on autopilot at 66,000 ft altitude for sortie duration periods of 3 to 4 hr. Each circle was completed in approximately 4 min time. Photographs taken with a radial scan-type camera were acquired from numerous, equally-spaced points around the circles and were used to construct mosaic disks, one for each circle, which provided a photographic record of the underlying cloud coverage throughout 360 degrees of azimuth angle, from horizon to horizon. The time series of mosaics revealed the spatial, temporal, and motion events that occurred within the fields of cumulus activity. The errors and uncertainties of the technique which were indicated by the tests are discussed. Examples are presented of the data acquired on the four test days and of their relation to conventional weather map, satellite, and radar information.