Air Quality Forecast over Northeastern U.S. with 3 domain configurations

This study investigates the impact of model domain extent on the forecast quality of air pollution constituents in a specific region of interest. The Eta-CMAQ modeling system has been providing experimental air quality forecast for the Northeastern region of the U.S. for the summers of 2003 and 2004. The model domain has been extended twice recently to accommodate a larger geographical coverage. The first extension was made to include the Eastern U.S., while the second was made to include the entire continental U.S. There are numerous insights about the impact of such extensions when the evaluation of the model performance is evaluated with respect to a specific region of interest; namely, the Northeastern U.S. Among the obvious major contributors of these impacts are the inclusion of a more detailed treatment of emission sources outside the immediate domain of interest, and the distancing of the lateral boundary conditions for the various precursor species. A qualitative analysis of these impacts has been summarized by investigating ozone episodes of similar synoptic weather patterns of the past 3 summers.