Physical, Chemical, and Optical Properties of Aerosols in Korea: Long-range Transport from Asian Continent

East Asia is an important source region of all major tropospheric aerosols. The fast economic development, the large area of desert and loess plateau, and the intensive forest and agriculture fires in this region contribute to 1/4 to 1/3 of global emissions of SO2, organic matter, soot, and dust. To reduce the uncertainty in the calculation of aerosol radiative forcing, it is necessary to understand the physical, chemical, and optical properties of aerosols on regional and global scale. Aerosol size distribution, chemical composition, and optical properties such as optical depth, scattering and absorption coefficient were made during the period from March 1998 to December 1999 in Korea. The characteristics of physical, chemical, and optical properties of aerosol were compared with air mass trajectories and meteorological conditions. The result shows that the long-range transport of aerosols from Asian continent is frequently occurred in Spring, especially accompanied by migratory anticyclone or passage of frontal system. In case study of Asian dust storm which is called as Yellow Sand in Korea, number concentration of coarse particle was rapidly increased. Sulfate, nitrate, and calcium ion concentration were also increased. Spectral aerosol optical depth in the air column during dust episode was 5 to 9 times higher than that of normal day. Aerosol extinction coefficient and single scattering albedo were also investigated to assess the radiative effect of aerosols by long-range transport from Asian continent.