The cumulus cloud events of the Florida peninsula that were observed during a 19-day period of photoreconnaissance in August and September 1957 are described and illustrated. The associated meteorological and rainfall events are also described and the intercorrelations among the various observations are pointed out. The study findings revealed that the principal factors governing the cloud and rainfall situations of the different days were (1) the low-level advection of water vapor into the peninsula from the oceanic surroundings, (2) the wind transport, into the heated peninsula from the oceans during the daytime, of pre -existing cumulus populations containing appreciable liquid water, (3) the low-level convergence, and associated updraft motion, engendered by the synoptic situation and the peninsula sea breezes, and (4) the precipitable water content of the lower Florida air mass. (Author)

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.

Of prime interest are the radiation data from that portion of the infrared spectrum known as the atmospheric water-vapor window, ranging from about 8 to 12 microns. Infrared signals received by weather satellites and aircraft depend, in clear air, on surface temperature, atmospheric interference and surface emissivity. For the latter, very different data in literature are found for clouds, water, rocks, etc. In this report correct emissivity data were sought in three ways: (1) Reflectivity of polished rock samples was tested in an infrared spectrograph for 5-16 microns wavelength. Using Kirchhoff's law this method yielded emissivities for near normal incidence. (2) Using an 8-13 microns sensitive radiometer and an aggregate, called emissivity box, the emissivity of many surfaces was measured directly. (3) A summer noon time flight of Tiros over the Mediterranean and the Sahara was evaluated.