“…However, it is not feasible to achieve the detailed spatial and temporal distribution of aerosols because of the scarcity of the direct observational data of aerosols. Hence, in addition to enhancement of field observation campaign, many scientists have made great effort to derive aerosol information from long history of other recorded meteorological data, such as solar radiation [King et al, 1978;Vasilyev et al, 1995;dacovides et al, 1996;Qiu, 1997;Marenco et al, 1997;Qiu, 1998;Gueyrnard, 1998]. Considering that large-scale direct aerosol observation is infeasible at present and even in the near future, indirectly retrieving aerosol information from other data is quite practicable.…”