Effects of Changing Power Plant Emissions on Ozone and Particulates in the Eastern United States

The impact of recent decreases in NOx emissions from many US power plants due to the implementation of control technologies was studied. Based on the EPA 1999 National Emission Inventory (NEI99) as a reference emission data set, selected power plant NOx and SO2 emissions were updated to their 2003 summer levels using Continuous Emission Monitoring System (CEMS) measurements. The validity of the CEMS data was established by comparison to observations made on the NOAA WP-3 aircraft as part of the New England Air Quality Study during the summer of 2004. The impacts of these emission changes on O3 and particulates were investigated using the WRF-Chem regional chemical-transport model. The significant decrease in power plant NOx emissions could make substantial improvements to air quality during typical summer high pollution episodes.