Investigating PM_2.5 pollution patterns in South Africa using space-time analysis

Abstract

<abstract> <p>The global concentration of fine particulate matter (PM_2.5) is experiencing an upward trend. This study investigates the utilization of space-time cubes to visualize and interpret PM_2.5 data in South Africa over multiple temporal intervals spanning from 1998 to 2022. The findings indicated that the mean PM_2.5 concentrations in Gauteng Province were the highest, with a value of 53 μg/m³ in 2010, whereas the lowest mean PM_2.5 concentrations were seen in the Western Cape Province, with a value of 6.59 μg/m³ in 1999. In 2010, there was a rise in the average concentration of PM_2.5 across all provinces. The increase might be attributed to South Africa being the host nation for the 2010 FIFA World Cup. In most provinces, there has been a general trend of decreasing PM_2.5 concentrations over the previous decade. Nevertheless, the issue of PM_2.5 remains a large reason for apprehension. The study also forecasts South Africa's PM_2.5 levels until 2029 using simple curve fitting, exponential smoothing and forest-based models. Spatial analysis revealed that different areas require distinct models for accurate forecasts. The complexity of PM_2.5 trends underscores the necessity for varied models and evaluation tools.</p> </abstract>