Development and application of a parallelized version of the advanced modeling system for transport, emissions, reactions and deposition of atmospheric matter (AMSTERDAM): 2. Source region contributions

The Advanced Modeling System for Transport, Emissions, Reactions and Deposition of Atmospheric Matter (AMSTERDAM) is an adaptation of the Community Multiscale Air Quality Model (CMAQ) that includes an advanced Plume–in–Grid (PinG) Treatment for resolving sub–grid scale processes associated with emissions from elevated point sources. A companion paper describes the parallelization of AMSTERDAM to make it a practical tool for PinG treatment of a large number of point sources, and the performance evaluation of the model for summer and winter periods in 2002. In this paper, we describe how the PinG treatment for large coal–fired Electric Generating Units (EGUs) affects model predictions of the ozone, particulate matter and sulfur and nitrogen deposition impacts from these sources using a number of emission control scenarios. The study examines the regional contributions of EGUs and non–EGU anthropogenic emissions from a “pseudo–state” source region defined around the center of the modeling domain. The pseudo–state region contribution studies are useful to understand inter–state and long–range transport of both primary and secondary pollutants. The results from these model applications show substantial differences between the PinG and non–PinG configurations of AMSTERDAM in their predictions of the magnitudes and spatial extents of EGU contributions to ambient ozone and PM2.5 concentrations. They also show that non–EGU anthropogenic emissions are the key contributors to ozone and PM2.5 concentrations and nitrogen deposition in neighboring states.