Experimental determination of Raman lidar geometric form factor combining Raman and elastic return

A straightforward method is presented for the determination of the geometric form factor in Raman–Mie lidar by using elastic backscatter signal from different altitudes and derived particle backscatter coefficients. The theory is briefly described. The error of this method is discussed and a comparison with the method proposed by Wandinger and Ansmann indicates the improved accuracy of the new method. The effect of the determined geometric form factor error on aerosol extinction coefficient retrieval is further discussed. The results of the experiment show that the derived aerosol extinction coefficient profile is less affected by the geometric form factor error when the atmospheric aerosol concentration is higher.