Simulation of air pollution from mobile source emissions in the city of Rio de Janeiro

A simple trajectory model and the chemical mechanism, including the chemist ry of ethanol and methyl-tert-butyl ether (MTBE), were used to simulate ozo ne concentrations at Avenida Brasil, a busy expressway in the city of Rio d e Janeiro where emissions from mobile sources are considered to be the majo r source of air pollution. The calculated ozone maximum of 22.4 ppb at 14:5 7 h is in good agreement with experimental measurements. Ozone isopleth dia grams were calculated based on the meteorological and emission scenario of that expressway, showing that ozone concentrations in Rio de Janeiro are a consequence of the high levels of NOx.