Wednesday, 14 January 2009: 4:30 PM
Development of the coupled 2-way WRF-CMAQ system
Room 127A (Phoenix Convention Center)
A 2-way coupled meteorology and air quality modeling system composed of the Weather Research and Forecasting (WRF) model and Community Multiscale Air Quality (CMAQ) model is being developed to enable simulation of multiple interactions between meteorological and chemical atmospheric processes. The coupled system includes direct effects of aerosol concentration, size distribution, and composition on short wave radiation. Simultaneous execution of meteorology and chemistry allows for high frequency data exchange that is necessary for high resolution modeling. Preliminary model results comparing simulations with and without aerosol feedback demonstrate significant impact of aerosol scattering and absorption on solar radiation, ground and near-surface air temperature, and PBL height. The direct aerosol feedback effects also lead to changes in atmospheric chemistry fields such as ozone and PM2.5. These preliminary results suggest that the largest effects on air quality come from changes in cloud fields caused by meteorology changes due to direct aerosol effects. Model development work is continuing to include indirect aerosol effects on cloud microphysics and the direct effects of tropospheric ozone on long wave radiation.