Aerosol Optical Properties Study Based On Ground Observation

Atmospheric aerosol is composed of solid and liquid particles suspended in the atmosphere and the atmosphere.The particle diameter is in the range of 0.001?m-100?m.Atmospheric aerosols play an important role in the transmission of atmospheric radiation.Aerosols can absorb solar radiation by scattering,thus affecting their energy reaching the ground.Aerosol can affect visibility and human health as a part of the atmospheric environment.Its concentration and spectral distribution have great changes in both vertical and horizontal directions.The extinction in the real atmosphere has a very complex mechanism,in which aerosol particles play a very important role in the scattering and absorption of atmospheric radiation,which is of great significance to the research fields of climatology,atmospheric radiation transmission,atmospheric exploration,etc.The aerosol particles in the atmosphere have obvious localization,and the optical characteristics of aerosol particles in different regions are very different.Therefore,the study of the optical characteristics of aerosol particles in different regions has certain reference value for the study of aerosol radiation models in different regions and the establishment of aerosol optical models in typical regions of China.The main work of this paper is divided into the following aspects:(1)The direct and scattered solar radiation in spring in Delingha of Qinghai Province,Hefei of Anhui Province and Maoming of Guangdong Province were measured by pom2 solar radiometer.The aerosol optical properties in spring in three regions were obtained by skyrad inversion algorithm,including AOD,AE,spectral distribution,refractive index and single scattering albedo.The results were analyzed.The results show that the concentration of aerosols in Delingha is lower than that in the other two regions;the AOD value increases greatly when the dust weather occurs;the distribution of aerosols in Hefei is relatively complex,and the AOD value in Maoming is concentrated in several regions;the wavelength index in Delingha is relatively small,indicating that the aerosols in this region are dominated by large particles,and the wavelength index of Hefei and Maoming is divided into two parts In a wide range,the wavelength index is relatively large,indicating that the sources of aerosols in these two areas are relatively complex,dominated by small particles.The volume concentration of fine particle mode in Delingha area is significantly lower than that in the other two areas,which indicates that the number of small particles in the atmosphere in this area is relatively small,and the number concentration of coarse particle mode in three areas of coarse particle mode is equivalent,and the concentration of coarse particle mode number in Delingha area is significantly higher than that of fine mode;the real part of refractive index in Delingha area is larger,the imaginary part is smaller,and the single scattering albedo increases with the increase of wavelength;The results of aerosol spectrum distribution and optical thickness change show that a large number of large particles enter the atmosphere during the dust weather,which is the main reason for the increase of aerosol optical thickness.(2)Based on the analysis of the data of solar radiometer and ground-based lidar in several typical areas,the optical thickness of the whole aerosol measured by the solar radiometer is taken as the constraint condition,and the lidar ratio of each area is retrieved.On this basis,the vertical distribution of aerosol is observed and studied.The average LRS of Delingha,Zhangye,Anhui,Hefei and Maoming are 38,62,47 and 17 respectively.Compared with the extinction profile obtained when LR=50,the extinction coefficients of LR obtained by inversion have the same trend with height,but the values of extinction coefficients at different heights are different.The vertical distribution of aerosols in different areas shows different spatial and temporal characteristics.(3)In order to study the optical properties of marine aerosols,the optical thickness,wavelength index,spectral distribution,refractive index,single scattering albedo and elevation of aerosol particles in the marine atmosphere were measured by means of solar radiometer,micro pulse lidar and automatic weather station in Qingdao,South China Sea,East China Sea and South China sea from July to November 2019.The results show that the aerosol optical thickness measured by the shipborne data is smaller than that measured by Qingdao and islands,and the aerosol elevation range is about 0.4-0.7,The diurnal variation is relatively stable,and the distribution of aerosol colloidal product spectrum in the offshore and the open sea has the same change trend.The radius of the coarse mode is about 2.4 ?m-3.6?M.compared with other data,the real part of the refractive index is larger,the imaginary part is.smaller,and the difference in the long wave band is more obvious.The single scattering albedo value basically does not change with the wavelength change.