SOURCE APPORTIONMENT OF VISIBILITY-DEGRADING AEROSOLS IN THE LOWER FRASER VALLEY, BC

The Lower Fraser Valley of British Columbia (LFV) is currently experie ncing rapid population growth and is perceived to suffer from reduced air quality, specifically, elevated ozone concentrations and impaired visibility. It is necessary to identify the sources of visibility-degr ading aerosols in order to develop strategies to prevent further degra dation and to institute measures to improve air quality in this region . Although chemical mass balance analyses have typically been used in such studies, herein, a P-mode principal component analysis (PCA) is p erformed upon the ambient aerosol species at one polluted site in the LFV, and source profiles are inferred from the resulting component loa dings. The loading coefficients on the five significant components (wh ich account for over 70% of the variance in the fine aerosol speciatio n dataset) are used to assess the contribution of these sources to par ticulate light scattering (b(sp)). Automobile emissions and wood burni ng are found to contribute most to b(sp) at this site.