Analysis of Chemical Components of Aerosols for Dust and Non-dust Cases during 1993-2002

Chemical components in aerosols at Gosan(Jeju in Korea) were analyzed for dust and non-dust cases from 1993 to 2002 through the backward trajectory analysis. The data are divided in five groups according to the pathway of air mass, and two groups(dust and non-dust). Mass concentration gradually increased yearly, and most components in aerosols have a large concentration at sector Ⅱ and Ⅲ(northern and southern China). Although the total mass concentration in the dust case is much greater than in the non-dust case, Ti, Mn, and V have similar proportions both sector Ⅱ and Ⅲ. The concentrations of the metallic components are greater in the dust case than in the non-dust case. Especially, the concentrations of Ti, Mn, and V in the dust case are about four times greater than in the non-dust case. The dominant ion component of aerosol is non-sea-salt sulfate(nss-$SO_42-$) in both cases. The concentrations of $Na^+$, $CI^-$, $NO_3-$, and nss-$Ca^2^+$ are about two times greater in the dust case than in the non-dust case. The mass concentration of $NO_3-$ in the dust case increased gradually, while the mass concentration of nss-$SO_42-$ in the dust case gradually increased at sector Ⅲ. As a result, the equivalent concentration ratio of$NO_3-$ to nss-$SO_42-$ increased since 1994, while the equivalent concentration ratio of nss-$Ca^2^+$ to nss-$SO_42-$ increased. The equivalent concentration ratio of $NO_3-$ to nss-$SO_42-$ was found to be larger in the dust cases. The result of this study means that the air mass flowing into Gosan has been polluted since 1993, especially the one from China. In the dust case the air mass has more pollutants than in the non-dust case.