COMPARISON OF THE SOURCE LOCATIONS AND SEASONAL PATTERNS FOR ACIDIC SPECIES IN PRECIPITATION AND AMBIENT PARTICLES IN SOUTHERN ONTARIO, CANADA

The Potential Source Contribution Function (PSCF) is a probability fun ction based on the air parcel trajectory data coupled with information regarding the nature of the contaminants measured in that air parcel. The PSCF value is the ratio of the probability of a contaminated air parcel having traversed a 1-degrees latitude by 1-degrees longitude ar ea to the probability that any air parcel traversed that area. Regions with high PSCF values thus have a higher probability of contributing pollutants to the measured concentrations at the receptor site. Previo usly, PSCF analysis has been used on precipitation chemistry data obta ined from the Acidic Precipitation in Ontario Study (APIOS) to locate the sources of the acidic precipitation. In this present study, the me thodology has been applied to both precipitation samples and particula te samples collected by the APIOS network. Analyses have been performe d separately for the winter and summer seasons so that the comparison between particles and precipitation and/or winter and summer can be ma de. From these results it is possible to identify the possible source locations for the observed constituents and at the same time, derive i nformation on atmospheric process by this study.