This paper reports the studies of the relationship between ambient NOx concentration and meteorological parameters like temperature, humidity, wind speed and wind direction. Based on this aspect the present study has been conducted with the monitoring of NOx level twice in a weak along with meteorological parameters of highly polluted zone of the city. To correlate meteorological condition with NOx level of selected area pearson correlation coefficient has been determine. It is found that wind speed and temperature are the main parameters which affect the NOx concentration in the ambient air. The wind direction with respect to different seasons is shown in wind rose diagram along with meteorological parameters such as temperature, wind speed. Wind rose diagram predict that pre-monsoon and post-monsoon was predominated by wind westerly where as monsoon period was predominated by west of north west (WNW) wind. Results of Pearson correlation coefficient shows the highest +ve significant correlation between concentration of NOx v/s temperature(r= 0.204) and concentration of NOx v/s wind speed r=0.117 and negative significant correlation was between concentration of NOx v/s relative humidity r=0.658.
KEYWORDS: Air Pollution, Statistical, Correlation Coefficient, Meteorological Parameters, Wind Rose Diagram.
In recent years, the deterioration of air quality in urban areas has been caused by continuous industrial and commercial development, population growth and an increase in energy consumption (Banerjee et. al., 2011, Turaliolu et. al., 2005). The concentration of air pollutants varies depending on meteorological factors, the source of pollutants and the local topography. However, of these three factors, the one which most strongly influences variations in the ambient concentration of air pollutants with the meteorological factors (Banerjee et. al., 2009). Although the relationships between synoptic meteorology and air pollution shave been investigated for pollutants such as ozone (Krupa et. al., 2003), S[O.sub.2] (Kalkstein et. al., 1986), N[O.sub.2] (Perez and Trier 2001), and even of visibility by (Sequeria R. and Lai, 1998). This study examines the relationship between meteorological parameters and urban air pollutants specially NOx concentration.
N[O.sub.x] represent a family of seven compounds. Actually, EPA regulates only nitrogen dioxide (N[O.sub.2]) as a surrogate for this family of compounds because it is the most prevalent form of N[O.sub.x] in the atmosphere that is generated by anthropogenic (human) activities. N[O.sub.2] is not only an important air pollutant by itself, but also reacts in the atmosphere to form ozone ([O.sub.3]) and acid rain. The release of oxides of nitrogen (nitrogen oxides and nitrogen dioxides) reacts with volatile organic compounds in the presence of sunlight to produce ground-level ozone, the primary ingredient in smog. Nitrogen oxide also...