One of the most promising methods to test the representation of cloud processes used in climate models is to use observations together with cloud resolving models (CRMs). The CRMs use more sophisticated and realistic representations of cloud microphysical processes, and they can reasonably well resolve the time evolution, structure, and life cycles of clouds and cloud systems (size about 2–200 km). The CRMs also allow explicit interaction between outgoing longwave (cooling) and incoming solar (heating) radiation with clouds. Observations can provide the initial conditions and validation for CRM results.

The Goddard Cumulus Ensemble (GCE) model, a cloud-resolving model, has been developed and improved at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center over the past two decades. Dr. Joanne Simpson played a central role in GCE modeling developments and applications. She was the lead author or coauthor on more than 40 GCE modeling papers. In this paper, a brief discussion and review of the application of the GCE model to 1) cloud interactions and mergers, 2) convective and stratiform interaction, 3) mechanisms of cloud–radiation interaction, 4) latent heating profiles and TRMM, and 5) responses of cloud systems to large-scale processes are provided. Comparisons between the GCE model's results, other cloud resolving model results, and observations are also examined.