Parameterization of Asian dust (Hwangsa) particle-size distributions for use in dust emission models

An improved dust emission model depending on the particle-size distribution constructed by the sum of three log-normal distributions of particle size of different soil types of Gobi, Sand, Loess and Mixed soil in the Asian dust source regions has been developed and implemented to an intense Asian dust event that has been observed in Korea from 2123 March 2002. The model has incorporated the concept of the minimally and fully dispersed parent soil particle-size distribution in the source region. The result indicates that the present emission model yields much better spectral-mass concentration distribution compared to those of previously used models of the power law and the log-normal distributions of particle sizes of the soil sampled from Australia in all spectral ranges, suggesting the usefulness of the present parameterization of the spectral dust emission to forecast the Asian dust event in Korea. It also indicates that the accuracy of the spectral-mass concentration largely depends on the availability of high-quality soil particle-size distribution data in the source region. (C) 2004 Elsevier Ltd. All rights reserved.