Nishanth.T and M K Satheesh Kumar
Diurnal variations of surface ozone and NOx* (oxides of nitrogen) at Kannur University campus (12.26N, 75.39E), a rural location and at Kannur Town, an urban location in Kannur (11.86N, 75.35E), a tropical coastal site in India have been studied during winter months in 2009 and 2010. The study revealed that surface ozone abundance is high at Kannur University campus than at Kannur Town. The maximum mixing ratios of surface ozone during winter at rural and urban sites were found to be (44.01±3.1) ppbv and (36.3±5.4) ppbv respectively, which is a clear indication of the air quality over these two locations during the season. Likewise, the ozone production is higher in the afternoon in winter months which in turn reveal the finger print of photolysis of NO2 * over these locations. The NOx mixing ratio shows a strong diurnal variability which substantiates the production of ozone from NOx.
