The global concentration of fine particulate matter (PM2.5) is experiencing an upward trend. This study investigates the utilization of space-time cubes to visualize and interpret PM2.5 data in South Africa over multiple temporal intervals spanning from 1998 to 2022. The findings indicated that the mean PM2.5 concentrations in Gauteng Province were the highest, with a value of 53 μg/m3 in 2010, whereas the lowest mean PM2.5 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 PM2.5 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 PM2.5 concentrations over the previous decade. Nevertheless, the issue of PM2.5 remains a large reason for apprehension. The study also forecasts South Africa's PM2.5 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 PM2.5 trends underscores the necessity for varied models and evaluation tools.
Citation: Tabaro H. Kabanda. Investigating PM2.5 pollution patterns in South Africa using space-time analysis[J]. AIMS Environmental Science, 2024, 11(3): 426-443. doi: 10.3934/environsci.2024021
The global concentration of fine particulate matter (PM2.5) is experiencing an upward trend. This study investigates the utilization of space-time cubes to visualize and interpret PM2.5 data in South Africa over multiple temporal intervals spanning from 1998 to 2022. The findings indicated that the mean PM2.5 concentrations in Gauteng Province were the highest, with a value of 53 μg/m3 in 2010, whereas the lowest mean PM2.5 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 PM2.5 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 PM2.5 concentrations over the previous decade. Nevertheless, the issue of PM2.5 remains a large reason for apprehension. The study also forecasts South Africa's PM2.5 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 PM2.5 trends underscores the necessity for varied models and evaluation tools.
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