Particulate Matter Source Apportionment Technology (PSAT) in the CAMx Photochemical Grid Model

Airborne particulate matter (PM) is important because it causes health problems and environmental degradation and accordingly many countries implement programs to control PM pollution (e.g., EPA, 1996). In recent years the emphasis on controlling PM pollution has shifted toward problems associated with fine PM (PM2.5 with particle diameter less than 2.5 μm) because it is more strongly associated with serious health effects than coarse PM. Knowing what sources contribute to fine PM2.5 is essential for developing effective control strategies. Many components of PM2.5 are secondary pollutants and so photochemical models are important tools for PM air quality planning. The Comprehensive Air quality Model with extensions CAMx; (ENVIRON, 2003) is one of the photochemical grid models being used to understand PM pollution and visibility impairment in the US and Europe. The Particulate Matter Source Apportionment Technology (PSAT) has been developed for CAMx to provide geographic and source category specific PM source apportionment. PM source apportionment information from PSAT is useful for: