Northwest China Aerosol Optical Depth And Wavelength Index Observation Data Analysis And Research

The aerosols optical depth and Angstrom exponent for 2002-2003 were derived from CE-318 sun/sky photometer observations carried out at Tazhong, Hetian, Minqin and Dunhuang, which are located in the typical source regions of mineral aerosols in China. The statistic properties of the observed mineral aerosols were presented. The diurnal and monthly variations of aerosol properties were given for each of the above-mentioned observational site. It is also analyzed that the effects of meteorological parameters, such as wind and relative humidity, on aerosol optical depth. Finally, the conclusion is that being the mineral aerosol belonging to non-hygroscopic aerosol is dominant aerosol type in northwest china, the correlation between AOD and RH is not obvious, but the surface wind speed has the evident correlation with AOD; The highest AOD always appear during noontime and afternoon that is corresponding to the higher surface wind speed and stronger convection current in whole day; the AOD of Taklamakan desert is higher than in Hexi corridor region especially in the spring and summer, but, with the AOD increasing from spring to autumn, the trend of AOD in four stations is similar each other ; in terms of AE, although the monthly value of Taklamakan desert is smaller than Hexi corridor region, the monthly fluctuation of AE in Taklamakan desert is smoother than Hexi corridor region; the main statistic character of AOD in northwest china is that the value of 0. 71+0. 043, 0. 65 ±0. 039 0. 33 ±0. 034 are of average value in spring, summer and autumn, respectively. The value of AOD is decreasing with the season change from spring to autumn. As to that of AE, the data of 0. 092 + 0. 012, 0. 158±0. 016, 0. 208 + 0. 021 are the average value in spring, summer and autumn, separately, the data of AE increase from spring to autumn.