SOURCE CONTRIBUTION OF ATMOSPHERIC AEROSOLS IN JAPAN BY CHEMICAL MASS BALANCE METHOD

The seasonal variation and regional features of source contributions to atmospheric particulates in Japan were investigated using a Chemical Mass Balance (CMB) method. The elemental concentrations of aerosol particles measured at the nine different National Air Surveillance Network from April 1977 to March 1985 were used in this study. Variations of estimated source contributions were also discussed for various analytical conditions regarding the types of release source and chemical species employed in the CMB analysis. When elements other than indicator elements of the assumed source types were added in the analysis by the CMB method, the contributions of some of source types were strongly affected. Soil source contribution was most significant among the five assumed sources at every site and was elevated in spring every year. On the other hand, the contributions of anthropogenic sources had peaks in early winter. © 1990.