Analysis of Aerosol Optical Properties in Dunhuang Area Based on CE318 Data
Based on the observation data of CE318 sun photometer,the aerosol optical depth(AOD),wavelength index(α)and turbidity coefficient(β)in Dunhuang City in the past four years were retrieved and calculated,and their annual,seasonal and diurnal variation characteristics were analyzed.The results showed that:(1)Compared with the eastern coastal area,the AOD in Dunhuang area was lower and the pollution was lighter overall.The annual average value of α was 0.2,indicating that the air pollution was mainly composed of coarse dust particles,which was a representative dust aerosol mode and the air condition was relatively clean throughout the year.(2)The aerosol showed obvious seasonal variation characteristics.AOD reached the maximum value of 0.67 from March to May in spring,showed a decreasing trend in summer and a slightly increasing trend in autumn,and reached the minimum value of 0.1 from December to February the next year.Meanwhile,the distribution of turbidity coefficient was positively correlated with AOD.(3)There were significant seasonal differences in the daily fluctuation of AOD,α and β.In spring,the fluctuation was more obvious,with the values of AOD,α and β being lowest before sunrise,reaching the peak at 11 o'clock every day,and then slowly falling and tending to be stable.In winter,the daily fluctuation was small and the values only increased slightly after sunrise,which was related to the stability of the atmospheric field in winter,and human production activities had little impact on it.To sum up,the atmospheric aerosols in Dunhuang area were mainly from natural sources,which were affected by frequent sandstorms in spring and autumn,especially in spring.The aerosol particles were larger and air pollutions were more serious in those two seasons.Dust storm was also the main factor affecting the change of aerosol in Dunhuang area.
万方数据
维普
