The monograph describes the concentrations of ambient NH3 and other trace gases (NO, NO2, SO2, O3 and CO) and its interaction over Delhi, NCR, IGP, Himalayan region and Bay of Bengal of India. The average concentrations of ambient NH3, NO, NO2, SO2 and CO were recorded as 21.2 5.4 ppb, 19.5 4.9 ppb, 17.4 1.4 ppb, 1.7 0.5 ppb and 1.6 0.7 ppm respectively during winter, whereas the average concentrations of ambient NH3, NO, NO2, SO2 and CO were recorded as 20.8 4.7 ppb, 21.7 6.3 ppb, 16.8 3.1 ppb, 2.2 0.8 ppb and 1.8 0.9 ppm respectively during summer at Delhi. The results emphasized that the...