Air pollution Inversion Levels in Tehran city

The purpose of the present study was to investigate the levels of temperature inversion and the effects it causes on the air pollution of Tehran. To this aim, 100 days from 2005 to 2009 which had the highest pollution levels were chosen from five stations. The inversion levels for these days were investigated through Skew-T graphs and the earth pressure plans in the levels of 900 to 300 hecto pascal. The results showed that between 73 to 85.5 percent of the air pollution in the Tehran stations are due to pressure systems and the high level of radiance from earth surface. The level of CO, PM10, SO2, was highest in Azadi station. The level of CO2 was highest in Rey station. The level of O3 was highest in Rey station. Although, the direction of the wind is from west to east but due to invergen as well as the low speed of wind, the wind flow does not influence the weather condition. Also, the spatial distribution of the weather pollution of Tehran showed that the amount of pollution is higher in center and west. In addition, from north to south the level of NO2 and O3 increase and the levels of CO, PM10, and SO2, decrease.