Abstract
Measurements of coarse (>2μm) and fine (≤2μm) particles concentrations in the aerosols of Nagoya urban area were made, and the natural burden to aerosols in urban air was described.
The arithmetic mean concentration of coarse particles except in spring was about 25μg/m3, which was in good agreement with the global background aerosol concentration in Japan. In spring, the yellow sand dust were transported from the Ordos and Gobi deserts, so that the concentration of coarse particles increased to 45μg/m3. The results of the arithmetic mean and coefficient of variation of coarse and fine particles concentrations indicated that the origin of coarse particles in urban air was not an anthropogenic source. From the concentration ratio of coarse particles to total aerosols, it was estimated that the environmental impact from natural sources was 35 to 40% of the total aerosols in the Nagoya urban area, and especially in spring was 50%.
