Microphysics Schemes in FV3GFS

It has been shown that there are issues in the precipitation and cloud radiative effects in the operational NCEP Global Forecasting System (GFS). The issues are identified as being related to the Zhao and Carr microphysics scheme. The scheme predicts only total cloud condensate. Some microphysical processes, especially the processes related to ice, are simplified or neglected. Precipitation falls to the surface within a single model time step and is not advected horizontally. As resolution increases this becomes particularly problematic. A few microphysics parameterizations, including the GFDL, Thompson, and Morrison-Gettelman schemes, are among the microphysics schemes being considered to replace Zhao and Carr in the next generation global prediction system (NGGPS) FV3GFS. Experiments have been conducted to test each scheme in this new modeling system. The results in terms of the precipitation skill, cloud properties and their radiative effects, and surface temperature will be presented in this study.