Cloud and convective systems play important roles in the energy and water cycles in the atmosphere and are thereby important in a wide range of problems related to climate and large-scale atmospheric variability on shorter time scales. My research deals with the interactions between processes on the scales of clouds and convective systems and large-scale atmospheric flows. Several methods are used to study the effects of clouds and convective systems on the thermal, moisture, and radiative fields which characterize the large-scale flows in which these systems develop. A primary application of this research is the development of parameterizations for clouds and convective systems for use in general circulation models.
      Recent research has centered on ice clouds and deep cumulus convection. The factors which determine the distribution of atmospheric ice and its consequences for climate are under examination. A unified procedure for treating the thermodynamics, hydrological and radiative interactions between deep convective systems and large-scale flows has been developed. Both of these problems are important in assessing the role of clouds in climate and climate change. General circulation models and high-resolution, limited-area cloud-system models are used in these studies, and data from satellite observations and field experiments are also employed. Some issues related to the role of cumulus convection in atmospheric chemical transport and transformation have also been addressed.