HR: 1400h
AN: A33A-01    [Abstracts]
TI: Preliminary Estimations of the Photostationary Parameter and Peroxy Radicals for the Atmosphere of São Paulo
AU: * Carbone, S
EM: samara@model.iag.usp.br
AF: University of São Paulo, Atmospheric Sciences Department - DCA/IAG/USP, Rua do Matão, 1226, São Paulo, SP 05508090, Brazil
AU: Galichio, W
EM: galichio@model.iag.usp.br
AF: University of São Paulo, Atmospheric Sciences Department - DCA/IAG/USP, Rua do Matão, 1226, São Paulo, SP 05508090, Brazil
AU: Fornaro, A
EM: fornaro@model.iag.usp.br
AF: University of São Paulo, Atmospheric Sciences Department - DCA/IAG/USP, Rua do Matão, 1226, São Paulo, SP 05508090, Brazil
AB: The Metropolitan Area of São Paulo (MASP) is a megacity with more than 17 million inhabitants and presents severe problems of the air quality, affecting the people health. In order to evaluate air quality of MASP, ozone was analyzed and the photostationary state (PSS) parameter and peroxy radicals concentrations were calculated using environmental measurements of ozone and nitrogen oxides. They were estimated from 09:00 to 18:00 h, local time. This preliminary analysis was first performed for four days at Ibirapuera Park, which has an official air quality monitoring station. Three of the chosen days, in spite of being cloudless, presented ozone values much higher than the standard air quality value (160 mg/m3). The fourth was a cloudless day, but was observed lower ozone concentration. The days with high ozone levels presented the PSS parameter higher than the unity almost all day long; sometimes it was higher than three times. These maximum values were observed from noon up to two in the afternoon and indicated the presence of other oxidants besides ozone at São Paulo. The day with low ozone levels presented PSS parameter values around the unity without maximum values, probably due to small amount of oxidants. The peroxy radicals oscillated between 5 and 701 pptv for the analyzed days and can be an indication of the high oxidant power in the troposphere of São Paulo.
DE: 0317 Chemical kinetic and photochemical properties
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly