Inversion of the lidar data in investigations of the optical characteristics of weakly turbid atmosphere

摘要

The problems, to which the single-frequency lidars are applied, can be conditionally divided in two types. The first type of problems is related to investigations of aerosol pollution: estimation of the mass concentration of industrial emissions and mapping of the spatial distribution of aerosol inhomogeneities. The principal peculiarity of this type of problems is the presence of optically dense anthropogenic aerosol cloud, that makes it possible to consider the laser sounding equation (LSE) for a single-component medium. The most outstanding and the most often used method for solving LSE in this case in the Klett method. The main problem, as at sounding of optically dense water clouds and fogs, lies in setting a boundary value. There are a number of papers devoted to the methods for estimating the boundary value σ(Z_0) under conditions of a priori uncertainty. Variability of the lidar ratio and neglecting the molecular scattering makes significantly less error in determining σ(z) in the problem of this type because of the greater optical density of aerosol formations. Application of the lidar to investigation of spatial and temporal dynamics of natural aerosol is related to the second type of problems. The problems of interpretation of the data, as at sounding of crystal clouds, lies in inverting LSE for a two-component medium relatively to β_(aer) using the Fernald method. Apart from the errors related to the a priori uncertainty in setting the boundary value, setting the profile S_a is necessary here. The purpose of this paper is determination of the method for stable reconstruction of the parameters of natural aerosol under conditions of a priori uncertainty.