Development of global aerosol forecasting system at NCEP

A module for tropospheric aerosols (the Goddard Chemistry, Aerosol, Radiation, and Transport model, GOCART) has been implemented into Global Forecast System (GFS). The new on-line aerosol forecast system extends current data assimilation and forecast capabilities for numerical weather prediction at National Centers for Environmental Prediction (NCEP). It is currently being evaluated with aerosol observations taken from various platforms (the pre-operational phase). At the end, the new system will enable NCEP to produce global short-range chemical weather forecasts, provide lateral boundary conditions for regional air quality forecast system, and create aerosol information needed for atmospheric corrections in satellite retrievals. In addition, the inclusion of prognostic aerosols in GFS provides a first step toward an aerosol data assimilation capability at NCEP. Since GFS is the AGCM of NCEP’s Climate Forecast System (CFS), the new aerosol element will allow NCEP to explore aerosol-chemistry-climate interactions in the climate system. This presentation will present online simulations of global aerosol distributions in the NCEP GFS and the comparisons to ground-based and space-borne aerosol optical observations.