Analysis on Aerosol Optical Property over Northern China from AERONET and SKYNET Observations

Abstract

The column-integrated optical properties of aerosol over northern China and southern Mongolia were investigated based on sun/sky radiometer measurements made at five Aerosol Robotic Network(AERONET)sites and one SKYNET site.Multi-year averaged daily and monthly changes of aerosol optical depth(AOD)andngstrm exponent were presented,and seasonal mean of aerosol volume size distribution,single scattering albedo,and asymmetry factor were also analyzed.The result shows that with the influence of dust storm activity every spring,the annual cycle of AOD show a spring and/or summer maximum,andngstrm exponent exhibited a springtime minimum,as well as the aerosol volume size distributions of coarse/fine mode presented different variation features.In addition,the aerosol optical properties of each station show the different changing trends associated with local anthropogenic pollution and biomass burning.For example,due to the influences of hygroscopic growth of aerosols from relative humidity increases in summer,the annual cycle of aerosol optical depth over Beijing and Xianghe stations show a summer maximum,and the single scattering albedo increase significantly.