Variations of ground level ozone in urbanized

Abstract

This study focused on ground level ozone concentration in 3 selected urbanized areas that are Shah Alam, Ipoh, and Malacca. Statistical Package of Social Science (SPSS) and Microsoft Excel were used in order to get the descriptive statistic of ozone concentration, air pollutant and meteorological parameters. The objective of this study is to observe the characteristics of ground level ozone in Ipoh, Malacca, and Shah Alam, evaluation of the correlation between the surface ozone concentration and its precursors (NOx and NMHC) and evaluation of the correlation between surface ozone concentrations with the meteorological parameters. The result of this study show that the ozone concentrations are below the limit (0.1 ppm) while only concentration of particulate matter size 10 μm (50 μg/m3) exceeded the Malaysian Ambient Air Quality Guideline permissible level. The diurnal variation of ozone in all selected urbanized area is found out to be low concentration during early morning and late night and high concentration during day time whereas NOx and NMHC show opposite pattern to ozone. It can be seen when ozone concentration begins to increase, and they peak around 15.00 – 16.00. During the night, the concentration of ozone appeared as a weaker peak. The correlation coefficient between ozone and the various meteorological parameters were weak except for certain pollutant in all selected urbanized area that resulted high emissions from common source such as vehicle exhaust, hence, enhanced the ozone formation.