Investigation of the relationship between atmospheric variables and the concentration of MP 10 and O 3 in the state of São Paulo

Abstract

This study aims to identify the relationship among weather variables, inhalable particulate matter (PM10) and ozone (O 3 ) concentrations registered in the state of São Paulo. Therefore, data from 2005 to 2014 from five air quality monitoring stations were used. The study is based in two methodologies: Principal Component Analysis (PCA) and meteo„rological means. In the PCA, for O 3 concentrations, positive correlations environment of 0.5 and 0.6 were found for air temperature, and negative correlations, of about 0.4 and 0.6 was found for relative air humidity. The contributions of the wind components to the O 3 concentrations differ from one location to another. In Cubatão and Bauru, the relation with southern winds is greater, and in the others the greater contribution is from the zonal component, however, in all these places the correlations are negative with O 3 . For PM10, lower values of correlation were obtained, negative with relative air humidity, and almost null with temperature. Correlations with wind components vary by location. Therefore, it is possible to conclude that MP10 ratios with moisture are more significant and, in the case of O 3 , among all variables, the correlation with temperature is the most important with the local and specific characteristics of each season. The average fields of the atmospheric variables reveal during the high concentrations of PM10 and O 3 the predominance of the South Atlantic Subtropical Anticyclone (ASAS) on the Southeast region of Brazil. In relation to the air temperature, the highest concentrations of ozone occurred on days with high temperatures, and with no significant difference in days of high concentrations of PM10. Finally, the highest concentrations of PM10 and O 3 occurred on dry days and in weak winds.