Variations of Carbon Monoxide Concentrations in the Megacity of São Paulo from 2000 to 2015 in Different Time Scales

José Rozante,Júlio Barboza Chiquetto,Antônio Ocimar Manzi,Demerval Moreira,Vinícius Rozante,Monica Siqueira D’Amelio,Débora Souza Alvim

doi:10.3390/atmos8050081

Abstract

Air pollution is an important public health issue. High levels of carbon monoxide in the atmosphere are hazardous to human health. Studies regarding the concentration of this and other gases in the atmosphere allow political actions to manage and reduce the emission of pollutants. In this context, this paper studied the annual, seasonal, weekly and daily variations of carbon monoxide (CO) concentration for the Metropolitan Region of São Paulo (MRSP). We studied three sites in the MRSP, two of them are located in areas under the influence of heavy vehicle traffic (Osasco and Congonhas) and the third one in a city park (Ibirapuera Park). The results showed high influence of gasoline vehicles on CO emission. In the annual scale, CO concentration decreased due to improvements in emission technology, despite the increasing number of vehicles. CO emission showed a seasonal, weekly and diurnal cycle associated to meteorological conditions and emission patterns. The highest values of mean concentration were observed in June/July for Osasco (2.20 ppm), Congonhas (2.04 ppm) and Ibirapuera (1.04 ppm), during the morning, due to weak dispersion of the polluting gases and higher emission from the rush hours.

Highlights

Urban atmospheric pollution has increased due to an increment in automobiles and industrial emissions, which worsen air quality and promote hazardous conditions for people, plants and animal life
The main carbon monoxide (CO) sources are combustion processes related to energy, heating, vehicle transport, biomass burning, the oxidation of methane and volatile organic compounds (VOCs)
We concluded that in terms of annual variations, CO concentrations decreased in all studied sites, in 0.114, 0.086 and

Summary

Introduction

Urban atmospheric pollution has increased due to an increment in automobiles and industrial emissions, which worsen air quality and promote hazardous conditions for people, plants and animal life. According to the Environmental Agency of the State of São Paulo (CETESB), about 97% of Carbon Monoxide (CO) concentrations are originated by vehicle emissions [2]. CO is a colorless, tasteless and odorless gas, flammable and dangerous to human health due to its toxicity and for promoting chemical asphyxiation. The main CO sources are combustion processes related to energy, heating, vehicle transport, biomass burning, the oxidation of methane and volatile organic compounds (VOCs). Its natural sources are volcanic activity, electrical discharge and natural gas emissions. CO is produced by chemical reactions in the atmosphere between the hydroxyl radical

Methods

Results

Conclusion