ATMOSPHERIC POLLUTION ASSOCIATED WITH PARTICULATE MATTER IN THE STATE OF SÃO PAULO: AN ANALYSIS FROM SATELLITE DATA

Abstract

Air pollution generated by anthropic activities affects both climate balance and air quality. Particulate matter (PM) is recognized as one of the air pollutants with the greatest impact on human health. In the state of São Paulo, the main anthropogenic sources of PM that affect air quality are vehicular emissions,
in urban region, and biomass burning, in rural areas. In order to mitigate pollution in rural areas, in 2007 the Agro-Environmental Protocol was signed between the State of São Paulo and the sugar and alcohol sector, which deals with the reduction and gradual elimination of the use of burning as a sugarcane harvesting practice until 2017. The analysis of the trend in the levels particular of pollutants in the state is fundamental for the evaluation of the results of the protocol. However, despite having the largest air quality monitoring network in Brazil, São Paulo still has most of its municipalities without any monitoring. In this context, aiming to evaluate the impact of the Agro-Environmental Protocol, the present study analyzed the spatial
and temporal distribution of the aerosol optical depth (AOD) in the state, an optical indicator of the abundance of MP in the atmosphere, derived from the spectral radiance measurements of the MODIS sensor on board the Terra satellite between the years 2007, when the protocol was signed, and 2017. The results revealed that when the influence of smoke transport from the North and Center-West regions of Brazil is removed, the satellite data adequately identifies the most polluted regions in the state, that are, the metropolitan areas of São Paulo, Campinas and Baixada Santista and the central and northern portions of the state, dominated by sugarcane plantations. In relation to the pollution trend, in the west and northwest areas of the state, where there has been an expansion of sugarcane cultivation in recent years, despite
the limitations imposed for burning by the Agro-Environmental Protocol, there was a significant tendency for an increase in pollution. In the areas of traditional sugarcane cultivation, in the central and northern portions of the state, although there was a tendency to reduce pollution associated with PM, this was not significant.