Assessment of Exceedances of Tropospheric Ozone Standards in São Paulo State from 2014 to 2019

Abstract

In this study, an analysis was performed using the air quality monitoring data for stations with exceedances of the ozone, aiming to characterize the spatial distribution and temporal variation of this pollutant, in the main regions of the State of São Paulo between the years 2014 to 2019. Ozone is a secondary pollutant and depends on the presence of its precursors in the atmosphere: nitrogen oxides and volatile organic compounds. The Metropolitan Region of São Paulo (MRSP) presents the greatest number of the Air Quality Standard (AQS) exceedances, mainly due to a greater precursor emission, a total of 875 exceedances from 2014 to 2019. The countryside presents 331 exceedances and the Metropolitan Region of Baixada Santista (MRBS) presents 24 exceedances in the same period. The years with the most number of exceedances are 2014 and 2019 for the MRSP, in the summer and spring, 2014 and 2017 for the countryside, mainly during spring, and 2014, 2015, and 2016 for the MRBS, mainly during summer. The peaks of exceedances are associated with favorable conditions for ozone formation: low precipitation rates, low nebulosity, high temperatures, and high solar radiation incidence. A possible alternative suggests that decreases in vehicular emissions should be considered.

Keywords
tropospheric ozone; air quality; metropolitan region of São Paulo; Estado de São Paulo; metropolitan region of Baixada Santista