Interrelationship between Diurnal ozone (O3) and the precursors at two industrial sites in Peninsular Malaysia: A functional data analysis approach

• Main Authors: Nazaran, Nur Afiqah Mohd, Shaadan, Norshahida, Shahri, Nur Huda Nabihan Md
• Format: Conference Proceeding
• Language: English
• Subjects: Data analysis; Emission analysis; Humidity; Mathematical analysis; Nitrogen dioxide; Ozone; Pollutants; Precursors; Standard deviation
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0115627

Investigating the complex interaction between air pollutants and the precursors helps to increase understanding of the emission sources. This study highlights the advantage of Functional Data Analysis (FDA) in the application for Ozone (O3) air pollutants and its association with several precursors; Nitrogen Dioxide (NO2), Carbon Oxide (CO) and meteorological variables; temperature and humidity for revealing new insights and theory. The data from the year 2009 until 2017 of two industrial sites; Petaling Jaya and Perai located in Peninsular Malaysia were obtained for the study analysis. FDA enables the identification of the average diurnal O3 pattern using functional median, the diurnal variability pattern using functional standard deviation and the temporal interaction pattern between O3 with the precursors and meteorological variables using functional correlation. The results have shown that, the average diurnal O3 and temperature pattern are similar at both sites with a single peak at 3.00 pm. Meanwhile, the pattern was dissimilar for CO, NO2 and humidity with multiple peaks. Indicated by the functional standard deviation, all variables particularly CO and NO2 level is higher and more volatile in Petaling Jaya than Perai. Functional correlation between O3 and the precursors suggests the Ozonation process is divided into four important phases; the pra-process, photochemical generation process, destruction process and post-process within 24 hours day period at both sites.