出版社：Thai Society of Higher Eduction Institutes on Environment
摘要：Hourly air pollutants data and weather parameters over the time period of 2008-2012 were
obtained from the Air Quality Division, Department of Environment (DOE) Malaysia. The
main aim of this study is to examine the variations of ground-level ozone in the west coast of
Peninsular Malaysia. Shah Alam recorded the highest number of hours and days of ozone
concentration above the threshold limit that was suggested by the Recommended Malaysian Air
Quality Guidelines (RMAQG) with a maximum concentration of 0.158 ppm. The highest ozone
concentration recorded in Petaling Jaya and Nilai were 0.12 ppm and 0.115 ppm respectively. The
diurnal pattern shows that the maximum concentration was observed in the afternoon, which
is the peak occurred between 2 p.m. to 4 p.m. and a minimum reading was recorded early in
the morning and night-time. Analysis of ozone concentration and its precursors showed that
the amount of Ultraviolet B (UVB) and the concentration of nitrogen dioxide had impacted the
ozone photochemistry through the titration processes. The results show that there are visible
seasonal patterns in the ground-level ozone among the three stations. The high concentration
of ozone is usually observed between January to April (end of northeast monsoon that bring
hot temperature from Cambodia) whereas the wind direction during different monsoons was
found out to influence the concentration of surface ozone.
