Sensitivity study of the multicomponent aerosol optical properties with various mixture types, refractive index and particle diameter

In this study, the aerosol optical properties for polydispersed size distribution are sensitively tested. Based on the filter sampled chemical composition data which measured in 2006-2007 in Seoul, South Korea, the extinction, scattering and absorption coefficient are calculated seasonally for various types of aerosol mixtures. The mixtures considered in this study are internal mixture, EC/non-EC external mixture and fully external mixture. This study also simulates the aerosol mass extinction, scattering and absorption efficiency for various mixtures as well as for various size distribution and refractive index. The results showed that the extinction coefficient can be mostly accounted for scattering and generally showed a good agreement with each mixture types in this case study. However, the absorption coefficient shows a different tendency for internal and external mixtures. This study also shows that the aerosol optical properties have different values as a function of particle diameter under the same composition and mass concentration. This means that mass extinction, scattering and absorption efficiencies, which used to be as a constant in general, should be reconsidered and more specifically described as a function of particle diameter.