Analysis of Stratospheric Ozone and Nitrogen Dioxide over Mid-Brazil for a Period from 2005 to 2020

This study analyses the stratospheric concentrations of ozone (O3) and nitrogen dioxide (NO2) over a 16-year period (2005 to 2020) over central Brazil using satellite data with the aim of determining the influence of NO2 on ozone distribution and the impact of fires and volcanic eruptions on these gases. The analysis shows that ozone and NO2 follow seasonal patterns, with the highest concentrations occurring in September and October and the lowest from January to June. A positive correlation was found between the concentrations of ozone and NO2, and the results of the Fourier analysis indicate semi-annual and annual cycles in the concentrations of these gases. Although there was an increase in the number of fires in the last 11 years of the study, this increase did not lead to significant changes in ozone or NO2 concentrations, indicating the stability of these parameters in the observed area. It is presumed that the reason for the lack of changes is lower intensity of fires despite their increased number. Regarding wind patterns, it is observed that they do not differ much either which is in accordance with the fact that the monitored area is fairly close to the equator.