Interrelationships between the ozone and nitrogen dioxide concentrations in the region of Grande Vitória, Espírito Santo, Brazil

ABSTRACT The objective of this paper was to determine the interrelationships between the ozone (O3) and nitrogen dioxide (NO2) concentrations, in the Grande Vitória Region (RGV), Espírito Santo, Brazil, using the methodology VAR and the Granger causality test. The VAR model captures the linear interdependencies between multiple time series. In this context, each variable has an estimated equation that represents its evolution in terms of its own lags and the lags of other variables. Granger causality test is based on a system of bivariate equations to check whether a variable is able to forecast the other. The results showed that the O3 and NO2 concentrations at Laranjeiras station were less affected by concentrations of other stations. The concentrations of Enseada do Suá were significantly affected by other regions, especially Jardim Camburi, IBES and Vitória - Centro. The Ibes ozone concentrations were strongly influenced by the O3 and NO2 concentrations from Enseada do Suá. Furthermore, the O3 and NO2 concentrations of Cariacica had significant impacts of concentrations of the Enseada do Suá, probably due to the prevailing North/Northeast wind direction in the RGV.