Correlation between smoke and tropospheric ozone concentration in Cuiaba during Smoke, Clouds, and Radiation-Brazil (SCAR-B)

Ozone soundings launched from Cuiaba between August 16 and September 10, 19 95, during the Smoke, Clouds, and Radiation-Brazil (SCAR-B) experiment show an enrichment of tropospheric ozone when compared with average wet season values and also present a great variability in concentrations depending on the dominant circulation pattern. Smoke tracers, such as aerosol optical th ickness, measured from a Sun photometer installed at the Institute Nacional de Pesquisas Espaciais-Cuiaba site, and black carbon ground measurements, also show an enhancement of smoke during the same period. Although there is a connection between the enrichment of the tropospheric ozone around Cuiab a during the dry season and smoke from biomass burning, the correlation bet ween ozone and smoke indicates different behavior in different periods. Tra jectory analyses suggest that the strong ozone peak measured in the period between August 26 and 29, 1995, may be associated not only with direct biom ass-burning emissions but also with urban/industrial emissions from big cit ies on the coast of Brazil and recirculation of old smoke. This view is con firmed by measurements made from the Cloud Lidar System instrument aboard t he ER-2 aircraft.