Observation And Study Of China's Eastern Region Aerosol Optical Properties

Measurments were made continuously for up to four months at three sites to study the aerosol optical properties in 2003. The sites were Lin'an regional GAW(Global Atmosphere Watch) station, Shangdianzi regional GAW station, Beiing Atmosphere Observation Station(BAOS). data of PM10 and PM2.5 were also collected separately at BAOS and Shangdianzi. The variation characteristics of aerosol scattering coefficient (δsp), absorption coefficient (δap)and single scattering albedo(SSA) were analysed based on the results of Lin'an and Shangdianzi regional GAW station. Meteorological data were used in the discussion on the correlation of δsp with visibility, relative humidity. The effect of local wind transportation on δsp and δap was analysed. In addition, the correlation of mass concentration and δsp was discussed. The results showed that δap at UV and shorter wavelengths were high than those at longer wavelengths. The values of δsp and δap measured at Lin'an were higher than those at Shangdianzi. Good correlations of δsp with PM2.5 and PM10 mass concentrations were found, where the correlations of δsP with PM2.5 were more significant. A negative correlation existed between δsp and visibility for all three sites. Local wind showed different effects on the δsp and δap at different sites. In Shangdianzi, a southwest wind contributed significantly to high δsp and δap, but northeast wind to low δsp and δap. This phenomenon at Shangdianzi can be well explained by the transportation of emission from Beijng urban area. The mean values(standard deviation) of SSA in Lin'an and Shangdianzi are 0.719(0.07) and 0.847(0.06) respectively . The diurnal variation of SSA is different remarkably from δsp and δap. .In noontime, high value distribution of SSA was found. Compared with SSA measured by foreign scientists, the values of SSA in Lin'an and Shangdianzi are lower.