Global Coupled Atmosphere/Ocean Modeling for Seasonal Forecast Applications at NOAA/ESRL
The atmospheric model uses column physics from the U.S. Weather Service's GFS/CFS. Initial results showed large regional biases in cloud cover, and hence shortwave radiative flux, in both coupled and uncoupled (AMIP style) global simulations. In an attempt to reduce these biases, we have modified the model to use the Grell-Freitas scheme for shallow and deep convection. A number of 1-year AMIP tests at different horizontal and vertical resolutions have been performed exploring the sensitivity to these changes/parameters.
Results of these tests and an optimal configuration of the FIM-iHYCOM coupled model are presented. We will evaluate MJO patterns and other model performance indicators on seasonal time scales against observations and model output from CFSv2.