9613979 Arakawa This award provides continued support for a research project devoted to the improving the representation of the physical processes relating to humidity and cloud fields in numerical models of the global atmosphere. In large part, the new research represents a continuation of activities and involves a broad range of topics. Among them are the development of a global version of a hybrid vertical coordinate model which will be used to simulate frontal clouds ; assessing the impact of including ice phase processes in a cloud updraft/downdraft model; improvement, based on cloud ensemble model results , of the cumulus parameterization; a statistical analysis of observations with a view to cumulus parameterizability; formulation of the decaying process for ice clouds; improving the formulation of the planetary boundary layer moisture budget; and the development of the parameterization of orographic gravity waves. Dr. Arakawa is acknowledged to be one of the great leaders in the field of numerical modeling of the atmosphere and continues to be quite productive. This project is supported jointly by the NSF through this award and NASA through a separate award. ***
