Análise das concentrações de poluentes atmosféricos de Porto Alegre e correlação com fatores meteorológicos.

Abstract

The air is an efficient means to the dispersion of atmospheric pollutants and its behavior depends on the atmospheric movements that occur in the troposphere. In this work, we studied the behavior of the daily concentration of the atmospheric pollutants, in Porto Alegre City – RS, analyzing the weather factors that can influence in its concentration. Porto Alegre is a city where there is an intense traffic and a concentration of industries that can be responsible for the atmospheric emissions. In this city, there is a constant monitoring, based on the actual environmental legislation, and this control is necessary to the life quality of the population, enabling the immediate action taking. To the data analysis, we used the descriptive statistical techniques, linear correlation, variance and multiple regression analysis. The data were supplied by Fundação Estadual de Proteção Ambiental Henrique Luiz Roessler – RS (FEPAM) and by Instituto Nacional de Metereologia (INMET). Through the analysis we concluded that: a) to the national air quality standards, the concentration of all analyzed pollutants, measured every day at 4 p.m., did not surpass the secondary and primary patterns; b) the highest monthly average of the ozone concentration (O3) was observed from September to January; c) the weather elements that influenced the most were the absence of humidity and the presence of solar radiation; d) the weather elements that influenced the concentration of Inhalable coarse particles were: the average daily temperature at 4 p.m. with positive relation; the daily average temperature of the dew point, the daily average wind speed and the daily average radiation, all at 4 p.m., with negative relations. We concluded, therefore, that the factors that contribute to the highest Inhalable coarse particles concentration (PM10) are the hot, with little wind and cloudy days; e) the wind direction that contribute significantly to the increase of the Inhalable coarse particles concentration are North and Northeast and the ones that contribute significantly to the diminishing of the concentrations in the places measured are East and Southeast.