UHF WIND PROFILERS - A NEW TOOL FOR DIAGNOSING TROPICAL CONVECTIVE CLOUD SYSTEMS

Uncertainty in the magnitude and distribution of diabatic heating asso ciated with precipitating cloud systems is one of the major factors gi ving rise to uncertainty in the simulation of large-scale atmospheric circulations in numerical models of the atmosphere. A major internatio nal effort is under way to develop an improved parameterization of the hydrological cycle within numerical models. Progress will require bet ter observations of the distribution of the diabatic heating associate d with cloud systems in the Tropics. In this paper new observations ar e presented demonstrating the potential of UHF profilers for diagnosin g the vertical structure of convective systems in the Tropics. These p reliminary results indicate that while mesoscale convective systems ar e prevalent in the Tropics them are important contributions to rainfal l from smaller-scale warm rain systems that do not extend above the fr eezing level. They also show that extensive regions of upper-troposphe ric precipitating clouds often exist at times when no rain is detected at the surface. These observations provide important information that should prove useful in developing improved methods for estimating pre cipitation from satellite observations.