Relationship Analysis of Air Pollution of Tehran with Traffic and Atmospheric Conditions for Hazards Mitigation

Air pollution is one of the most important environmental hazards in Tehran metropolitan that with understanding and cognition of factors which affecting pollution can reduce adverce effects of it. In order to reduce these effects, accurate studies on the basis of effective factors on pollutant is essential. The goal of this research is to analysis variation of air quality index(AQI) in relation to atmospheric conditions and traffic in Tehran. The Pearson correlation coefficient and regression analysis were used in order to compute the relationship between air quality indices(average and maximum) with traffic and meteorological variables. This study was done during 60 days (November,6th to January 5th) for the 2010 to 2012 years. The results revealed that atmospheric unstability index (ki-index) has the most impact on air pollution variations. Multiple linear regression  models for the year 2011 was the most accurate model to estimate maximum air quality index with the least relative deviation, RD (RD of -0.05 for first model and -0.1 for second one). An important achievement of this study was indirect correlation between number of vehicle and air quality index which is not happened to the reality. It seems that pollutant production in two cases including car’s movement or stop are quite different from each other and should be investigated using other methods.