Home – Home – Jornals – Atmospheric and Oceanic Optics 2016 number 1

The article is devoted to the methodology of obtaining the spatial distributions of respirable fractions of aerosol in the atmosphere from multifrequency lidar sounding data without the use of additional optical and microphysical aerosol parameters on the path under study. For this purpose, it has been suggested to replace the spectral values of the aerosol extinction coefficient involved in lidar equations by the linearly independent parameters of their approximation, and retrieve the spatial distributions of these parameters from the numerical solution of the system of equations created from all spectral-temporal readings of lidar signals. As a result, the number of unknowns in the system of equations, which are solved, is significantly reduced, and its matrix becomes well-conditioned that can be used to select physically reasonable values of backscatter-extinction aerosol ratio at the operating lidar wavelengths. The assumption that there are two segments with the similar profiles of aerosol extinctions coefficients is used to determine the calibration constants of lidar. The algorithm for searching such segments from the spectral-temporal structure of lidar signal is suggested. The inverse problem of aerosol light scattering is solved on the basis of stable regression relations between the concentrations of respirable aerosol fractions and approximation parameters of its extinction spectrum. The tolerance of the technique developed to the calibration errors and the spatial variations in backscatter-extinction aerosol ratio is shown from numerical experiment on laser sounding of aerosol.