Analysis of Variability of Atmospheric Pollutants in Ambient Air of Metropolitan City Karachi, and Environmental Sustainability

Abstract

It is well known that, air pollution is a composite phenomenon and intense air pollution events are governed by huge number of consistent factors. In this study, we considered the pollutant parameter (NO2, NO, NOx and CO) concentrations and were measured simultaneously during the period 21/11/2009 to 27/02/2010 in city of Karachi. The estimations were carried out to study the variability of pollutant emissions. Time Series analysis confirms the existence of variation in pollutant with mean daily concentration and the results suggest that the concentrations of pollutant over the interval are slowly declined. The relationships NO2 with NOx, NO with NOx and NO2 vs. CO were modeled with linear regression. The results of the linear regression detected underlying strong relationships among pollutant variables. The application of the regression approach confirmed that the NO2 strongly correlated with other paired pollutants. The study will be helpful to the policy makers to control air pollution and the sustainable environment. It also needs to extend this research to study the nonlinear behavior of atmospheric pollutants in perspective of fractal dimension.

Spatio-temporal variations of lower tropospheric pollutants and their relation with meteorological factors in Karachi, Pakistan

“…The present study reveals that all the nitrogen oxides are closely correlated at all designated sites. Jan et al (2017) found a similar correlation between various nitrogen oxides when analyzing their data of 98 days air quality of Karachi. They also a rmed a signi cant correlation of carbon monoxide (CO) with each oxide of nitrogen.…”

“…Consequently, the developed countries started to monitor ambient air pollution a few decades back (Crippa et al, 2015), followed by the developing countries to address the apprehension regarding urban air pollution (Gulia et al 2020;Zhang et al 2020;Guttikunda et al 2019;Hashmi et al 2018;Jan et al 2017;Wu et al 2017;Chen et al 2007;Barletta et al 2002;Shams and Beg 2001). Many researchers investigated the correlations between meteorological factors and outdoor air pollutants across the globe (Kayes et al, 2019;Zhang et al, 2015;Karagiannidis et al, 2015;Jassim et al, 2018;Kalisa et al, 2018;He et al, 2017;Pearce et al 2011).…”

“…For instance, Barletta et al (2002) investigated the mixing ratios of 72 air pollutants, mainly methane and non-methane hydrocarbons of the city atmosphere. Jan et al (2017) correlated outdoor air pollutants of Karachi, and Hashmi et al (2018) classi ed the study sites of the same city based on their air quality index. Shams and Beg (2001) monitored ambient carbon monoxide in the streets of the metropolitan area.…”