Assessment of Ground Level Ozone Weekend and Weekday Due To Variation in Nitrogen Dioxide Concentration

Ozone is considered as a secondary pollutant as it is a byproduct of photochemical reaction. In normal condition, it will react with NO to form NO2 and O2 but VOCs are more attract to NO, the forward reaction is preferred lead to the creation and buildup of O3. High concentration of ozone and nitrogen dioxide caused by eminent levels of anthropogenic and natural ozone precursors is the one of the main challenges for countries in tropical areas and valuable indicators of possible to health and also environment impacts. The study describes the variations of O3 and NO2 concentrations in weekdays and weekend at selected monitoring stations. This study investigated the variations in O3 and NO2 concentrations at two locations which are SMK Tanjong Chat, Kota Bharu Kelantan and SK Indera Mahkota, Kuantan Pahang using two-year (2013-2014) secondary data obtained from the Department of Environment, Malaysian (DoE) while verified by using primary data at Kota Bharu in 2017. The concentrations of O3 and NO2 during weekdays and weekend were analyzed using descriptive statistic, box and whisker plot, time series plot, diurnal plot and independent t test. The mean of O3 concentration were recorded higher during weekdays (25.87 ppb) and weekend (23.83 ppb) in Kota Bharu 2013 while lower during weekdays (12.04 ppb) and weekend (12.28 ppb) in Kota Bharu 2017. The diurnal patterns of O3 concentration during weekdays and weekend for both locations showed a consistent trend with obviously different magnitude. The maximum level of O3 concentration showed at noontime which is 12 noon to 2 p.m., while the minimum level of O3 concentration showed at nighttime 6 p.m. to 10 p.m. The time series illustrated that the changes of volatility of concentrations may also be due to changes of monthly seasonal throughout the year because its highly related and can effects the pollutants. The result suggest that the concentration of O3 is higher during weekdays than weekend for both place and was still below the maximum permissible values prescribed by the MAAQG.