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This paper presents results of a study of aerosol pollution distribution and dynamics measured by lidar observations over the city of Athens. The seasonal dynamics of vertical changes in the backscattering coefficient, extinction coefficient and lidar ratio for lower troposphere has been determined.

The paper gives a general inversion algorithm for lidar's data derivation and profiles of the extinction coefficient, backscattering coefficient and lidar ratio for the lower troposphere. To the best of our knowledge these are the first results obtained with this algorithm.

A novel backscattering lidar inversion procedure is presented. This method consists of two steps: the first one is the determination of a preliminary vertical profile of the unit volume extinction coefficient by the iterative Klett's method, and the second one is the determination of the vertical profile of unit volume backscattering coefficient from the previous step --using the relationship between (alpha) (r) and (beta) (r) -- which is given by two independent solutions for both variables. The calculation of the vertical profile of the 'lidar ratio' [determined as: (beta) (r)/(alpha) (r) is automatic ]. The proposed method is applied, in a preliminary case, to several backscatter lidar signals, obtained by a two wavelength backscattering lidar system in Greece. The proposed procedure can be applied for each wavelength of a multiwavelength backscattering lidar system, independently -- which means that the unit volume extinction and backscatterer profile of the atmosphere can be spectrally resolved. The general case of this procedure has not been applied yet, to a computer simulation, while this work is still in progress.