Seasonal and Spatial Zoning of Air Quality Index and Ambient Air Pollutants by Arc-GIS for Tabriz City and Assessment of the Current Executive Problem

Air pollution threatens the health of urban dwellers. Tabriz city is among the seven megacities of Iran with air pollution dilemma. The aim of study was to survey and characterize air pollution in the city of Tabriz regarding air quality parameters and administrative problems.
This is a descriptive- analytic study which Tabriz ambient air was the study area. The data obtained from five air pollution monitoring stations was used in this study in the period of 2012-2013. Air quality data and meteorological characteristics were integrated to demonstrate spatial and temporal variations of air quality. Approximately, at 30 to 50% of the times, the data has not been recorded at the monitoring stations. Inverse Distance Weighting (IDW) method was used to analyze allocation of air pollution at other parts of the city.
The highest concentration of PM10 was related to summer and winter seasons with about 117 µg/l which mostly were excessive than the air quality limits. Carbon monoxide was at the highest amount of 7.66 µg/l at the cold months and brought about unhealthy condition. Concentrations of O3, NO2 and SO2 mostly were less than the permissible limits and at about 5% of the events led to initiate unhealthy conditions. Estimations show that the numbers of monitoring stations are not sufficient and additional 21 stations are required.
PM10 and CO are attribute to the main pollutants of air in Tabriz city and the most events of air pollution take place at cold seasons. Increasing the number of monitoring stations and establishing appropriate daily measurement systems of pollutants is one of the important management measures to control air pollution in Tabriz.