Measurement of Ground Level Ozone at Different Locations

Abstract

Problem statement: Ground level ozone is the most important index substance of photochemical smog. Photochemical smog is now observed in many urban and industrial centers around the world and it has become a common phenomenon in many large cities. Ozone is a most harmful pollutant for humans, in addition it plays an important role in damaging vegetation and materials. Therefore it becomes important to measure the ground level ozone at different locations especially in the center of cities. Approach: The ground level ozone concentration at different locations in Baghdad city was identified. Five different sites have been chosen to identify the ground level ozone concentration. Two sites were chosen as areas contained point source (power plant station) in addition to high traffic load and the other three sites were chosen as areas containing heavy traffic only (line source). The measurement focuses on spring and fall because these periods display favorable meteorology to ozone formation. Results: During the research period the maximum values (peaks) for ground level ozone concentration were observed in the fall: at Al-Za’afarania area 101ppb as an average, at Al-Dora 87 ppb as an average (which represent the point sources) and at line source areas 48 ppb as an average. In spring, the peaks of ozone concentration observed to be at the same height, about 50 ppb for all sites. Conclusion: The results show that the effect of power plant stations in forming ozone is larger than traffic load. The comparison between the ground level ozone concentrations that measured during the research period in spring and fall and the Ambient Air Quality Standards (AAQS) shows that: (1) No exceeded levels were observed in spring for all sites. (2) In the fall, the AAQS for ozone was exceeded in Al-Za’afarania area at 12: PM, 1: PM, 2: PM and 3: PM and in Al-Dora at 2: PM.