Aerosol and cloud optical properties measured by a Raman lidar

摘要

This paper describes one Raman lidar system for measurements of optical parameters for tropospheric aerosol and cirrus at Hefei (31.9°E/117.17°E) station. Typical extinction and backscatter coefficients profiles of tropospheric aerosol and cloud are presented. Many observation cases show the positive relationship between aerosol optical parameters and water vapor distribution. Some aerosol distributions were captured for dust storm by this Raman lidar in the spring of year 2001～2002. Angstrom coefficient profiles of aerosol are derived in the free troposphere by combining two-wavelength Raman-elastic scattering channels, those values indicate smaller for dust aerosols. Optical thickness and scattering ratio profile of cirrus are obtained by this Raman lidar. The values of extinction to backscatter ratios are frequently found between 20 sr and 70 sr for free tropospheric aerosol, but less than 20 sr for cirrus clouds.