Descriptive Analysis of Air Pollution and Meteorological Trends Across Peninsular Malaysia: Insights from Air Monitoring Stations

The study investigates the relationship and descriptive tabulation of meteorological parameters and air pollutant variables in air quality monitoring in Peninsular Malaysia from 2017 to 2022. The main objective is to understand how the different weather conditions and pollutant variables are distributed across all monitoring stations in Peninsular Malaysia to provide insights for environmental monitoring and public health policy. Approximately 111,345 daily averages were collected from continuous air quality monitoring stations in Peninsular Malaysia (CAQMS) under the supervision of the Department of Environment (DOE), Malaysia. Key meteorological parameters such as wind direction (WD), wind speed (WS), relative humidity (RH), solar radiation (SR) and ambient temperature were analysed together with air pollutant variables such as nitrogen oxide (NOx), nitric oxide (NO), nitrogen dioxide (NO₂), ozone (O₃), carbon monoxide (CO) and particulate matter (PM10 & PM2.5). Statistical analysis was performed using Spearman’s correlation to identify significant predictors of air quality monitoring. In the descriptive analysis, all CAQMS were compared with each other, including the mean. Boxplots were shown to describe the meteorological parameters, and correlation amongst the parameters and variables were done to investigate relationships. Results showed that PM2.5 mean value exceeded the WHO guideline of 15μg/m³ and some CAQMS showed higher mean values especially in the central region (Selangor and Nilai, Negeri Sembilan). Carbon monoxide exhibits moderate correlation to certain air pollutant variables including PM2.5 which is a significant air pollution indicator in peninsular of Malaysia.