Variations in Mixing Ratios of Ambient Ammonia, Nitric Oxide and Nitrogen Dioxide in Different Environments of India

Abstract

° 38'N, 77 ° 10'E; 220m m.s.l.), India (Figure 1) during July 2009. Delhi, the capital city of India, located in the northern part of India. It is one of the ten most polluted cities of the world and third most polluted city of the country having numerous industries in and around the city. The total number of registered vehicles in the city Abstract Mixing ratios of ambient NH3, NO and NO2 were measured over three different environments viz Delhi, Dibrugarh and Thiruvananthapuram during 2009-10 to study their diurnal variations, concentration and source strength. The average mixing ratio of NH 3 over Delhi, Dibrugarh and Thiruvananthapuram were recorded as 13.24 ± 0.39, 13.46 ± 2.52 and 12.65 ± 1.51 ppb respectively. The average mixing ratio of NO2 was recorded as 12.69 ± 0.39 with maxima of 20.22 ppb and minima of 0.75 ppb over Delhi whereas, the mixing ratio of ambient NO 2 ranges from 0.65 to 3.65 ppb and 0.83 to 3.02 over Dibrugarh and Thiruvananthapuram respectively. The mixing ratio of NO and NO2 varying significantly at all the three locations except NH 3 might be due to source strength and meteorological conditions of the locations. Result reveals that the mixing ratio of ambient NH 3 is positively correlated with ambient temperature (r 2 = 0.872) and NO2 (r 2 = 0.975) over Delhi whereas non-significant at other locations.