Modelling driving factors of PM2.5 concentrations in port cities of the Yangtze River Delta

PM 2.5 is one of the major air pollutants in port cities of the Yangtze River Delta (YRD) of China. Understanding the driving factors of PM 2.5 is essential to guide air pollution prevention and control. We selected 17 major port cities in YRD to study the driving factors of PM 2.5 in 2019 and 2020. Generalized Additive Models were built to model the non-linear effects of single, multiple and interactions of driving factors on the variations of PM 2.5 . NO 2 , SO 2 and the day of year are most strongly associated with the variation of PM 2.5 concentration when used alone. Anthropogenic emissions play complicated roles in regulating PM 2.5 concentration. Although the effect of cargo throughput (CT) on PM 2.5 concentration is non-monotonic, higher PM 2.5 levels are found to be associated with higher levels of SO 2 and CT. This work can potentially provide a scientific basis for formulating PM 2.5 prevention and control policies in the region.