Retrieval of microphysical properties of aerosol particles from one-wavelength Raman lidar and multiwavelength Sun photometer observations

Abstract

Aerosol Raman lidar observations of particle extinction and backscatter coefficients at 532 nm are combined with Sun photometer observations of the particle optical depth at six wavelengths from 381–1044 nm to derive column-integrated microphysical properties of boundary-layer aerosol such as volume and surface concentrations, effective radius, refractive index, and single scattering albedo. The method is based on our well-tested lidar inversion algorithm and is applied to observations carried out in the heavily polluted Pearl River Delta (PRD), in South China. Different data sets consisting of six extinction coefficients and two backscatter coefficients (measured at 532 nm, estimated at 381 nm), and alternatively, of five extinction coefficients only are used in the inversion retrieval. The results are discussed and compared with ground-based in situ observations of aerosol microphysical properties. Volume concentration, effective radius, real and imaginary part of the refractive index of the particles are determined with a relative uncertainty of 30%, 40%, 10%, and 70%, respectively.