Quantifying and evaluating the effect of urban expansion on the fine particulate matter (PM2.5) emissions from fossil fuel combustion in China

There is no consensus on the effect of China’s rapid urban expansion on the fine particulate matter (PM2.5) emissions from fossil fuel combustion (PC). Previous studies usually focused on the environmental effect of urban expansion from a single mode (e.g., spatial expansion). However, studies that simultaneously considered and compared the effect from spatial and socioeconomic modes are still lacking. Thus, we combined multiple data sources (e.g., nighttime light data, urban land datasets, and PC) and econometric methods to evaluate the effect of urban expansion on PC within different regions from spatial and socioeconomic modes. The results show that China’s urban socioeconomic expansion (UE) and urban spatial expansion (US) increased from 68.50% and 11.81 × 10−4, respectively, in 1992 to 72.23% and 66.86 × 10−4, respectively in 2012. The UE is the Granger cause of the increased PC in China. Through variance decomposition analysis, we also found that the UE contributed much more to the PC in China than the US. When comparing the different regions, we recognized that the UE was the key factor in explaining the increase in the PC in the eastern and northeastern regions, and the US could effectively explain the changes in the PC in the central region. The study provides a novel perspective for quantifying the effect of urban intensive and extensive development on haze pollution.