Prediction of Ozone Concentration at Selected Coastal Sites in Peninsular Malaysia Using Probability Distribution

Abstract

Generally, high ground-level ozone concentration can affect human health, agriculture and materials. The aim and objectives of this study is to determine the monsoonal variability of ozone concentration in selected sites (Kemaman, S1; Pulau Langkawi, S2; Kuala Terengganu, S3; Universiti Sains Malaysia, S4; Tanjong Malim, S5) accompanied with prediction via statistical distribution. Four different parent distributions such as gamma, Laplace, Rayleigh and log-logistic were applied in order to achieve second and third objectives. Matrix Laboratory version 2014 (MATLAB R2014a) was used to estimate the maximum likelihood estimation (MLE) and method of moment (MOM) distribution parameters; thus obtaining probability density function (PDF), cumulative distribution function (CDF) and performance indicator. Five selected performance indicator used in this study were mean biased error (MBE), normalized absolute error (NAE), prediction accuracy (PA), index of agreement (IA) and coefficient of determinant (R2). The hourly ozone concentrations that exceed 100 ppb (Malaysia Ambient Air Quality Guideline, MAAQG) are considered exceedances event. The exceedance probability that exceeded MAAQG line in CDF plot was later used in achieving the third objective.