São Paulo (23°33'5, 46\ub044'W, 780 m ASL) is one of the most polluted cities in the world, Tegardirlg atmospheric air quality, (CO, suspended aerosol particles). In this paper, we present the first aerosols obscrvations perfomed by an elastic back.scatter lidar sysltm, over the city of São Paulo. The lidar- measurements concerned the retrieval of the vertical profile or the aerosol backscatter coefficient at 532 nm, using the Klett inversion technique. in the Planetary Boundary Layér (PBL) and me adjacent lower free troposphere. Systematic aerosols observations to be performed during the year 2001, wiIl enable the characterization of the various tropospheric layers, ând hclp to dcsign an efficient air pollution abatement strategy in thc city of São Paulo.Pages: 8407-840
