Uncertainty in the magnitude and distribution of diabatic heating associated with precipitating cloud systems is one of the major factors giving rise to uncertainty in the simulation of large-scale atmospheric circulations in numerical models of the atmosphere. A major international effort is under way to develop an improved parameterization of the hydrological cycle within numerical models. Progress will require better observations of the distribution of the diabatic heating associated with cloud systems in the Tropics. In this paper new observations are presented demonstrating the potential of UHF profilers for diagnosing the vertical structure of convective systems in the Tropics. These preliminary results indicate that while mesoscale convective systems are prevalent in the Tropics there are important contributions to rainfall from smaller-scale warm rain systems that do not extend above the freezing level. They also show that extensive regions of upper-tropospheric 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 precipitation from satellite observations.
*Aeronomy Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado.
+Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado.