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Brazil has an important role in the biomass burning, with the detection of approximately 100,000 burning spots
in a single year (2007). Most of these spots occur in the southern part of the Amazon basin during the dry season
(from August to november) and these emissions reach the southeast of the country, a highly populated region
and with serious urban air pollution problems. With the growing demand on biofuels, sugarcane is considerably
expanding in the state of Sao Paulo, being a strong contributor to the bad air quality in this region. In the state
of Sao Paulo, the main land use are pasture and sugarcane crop, that covers around 50% and 10% of the total
area, respectively. Despite the aerosol from sugarcane burning having reduced atmospheric residence time, from
a few days to some weeks, they might get together with those aerosol which spread over long distances (hundreds
to thousands of kilometers). In the period of June through February 2010 a LIDAR observation campaign
was carried in the state of Sao Paulo, Brazil, in order to observe and characterize optically the aerosols from
two distinct sources, namely, sugar cane biomass burning and industrial emissions. For this purpose 2 LIDAR
systems were available, one mobile and the other placed in a laboratory, both working in the visible (532 nm)
and additionally the mobile system had a Raman channel available (607 nm). Also this campaign counted with
a SODAR, a meteorological RADAR specially set up to detect aerosol "echoes" and gas-particle analyzers. To
guarantee a good regional coverage 4 distinct sites were available to deploy the instruments, 2 in the near field of
biomass burning activities (Rio Claro and Bauru), one for industrial emissions (Cubatao) and others from urban
sources (Sao Paulo). The whole campaign provide the equivalent of 30 days of measurements which allowed us
to get aerosol optical properties such as backscattering/extinction coefficients, scatter and LIDAR ratios, those
were used to correlate with air quality and meteorological indicators and quantities. In this paper we should
focus on the preliminary results of the Raman LIDAR system and its derived aerosol optical quantities.
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