Comparison of Air Pollutants Between Kolkata and Siliguri, India, and Its Relationship to Temperature Change

摘要

The rapid pace of economic growth and urbanization in Kolkata affects both the people and places. As the city grows physically, it counters several environmental degradations including air pollution. Siliguri, the gateway to north-eastern India, is also under deplorable environmental conditions with a growing industrial sector and rapid urbanization. This study aims to portray the current air pollution situation with seasonal variation in three zones (two from Kolkata and one from Siliguri) as it evaluates the present level of different air pollutants like particulate matter (PM), carbon monoxide, nitrogen dioxide, and sulfur dioxide. The result of the seasonal analysis shows the critical level of air pollutants, especially PM2.5 and PM10, has reached its highest concentration during the post-monsoon season in the Rabindra Bharati University zone (363.5 and 295.4 mu g/m(3) respectively during the daytime) of Kolkata, and thereafter, monthly characteristics of the most variant seasonal pollutants were examined in the studied areas. These seasonal fluctuations of pollutants reflect the impact of meteorological conditions, as such pollutants coming out from different sources are also raising temperatures. Therefore, this work also tries to justify the environmental pollution scenario using Spearman's rank correlation coefficient method between the average temperature of a day (degrees C) and the level of air pollutants (mu g/m(3)) like PM2.5 and CO, separately. Positive values of correlations may indicate the contemporary status of the air quality, as well as the environmental state, that will be an important basis for further regional studies on air quality and distribution of sources.