The research team of Arakawa and Mechoso represents a highly successful and productive collaboration which has made many contributions to the advancement of numerical modeling of the atmosphere over the years. Under this award, they will continue their research, focusing on three topics: (1) the physical and conceptual basis for cumulus cloud parameterization in global models and the development of a cloud model for use in that parameterization, with special attention to role of the cloud's "environment", both above and below; (2) mathematical formulations for moisture advection in their hybrid sigma-theta coordinate model of grid-scale hydrological processes, and (3) the effects of subgrid-scale variations of model lower boundary conditions involving both orographic and non-orographic gravity waves and variations in the thermodynamic properties of the surface. Advances in all of these areas will improve the performance of atmospheric models for research and forecasting purposes.
