Driving forces of carbon dioxide emissions in China’s cities: An empirical analysis based on the geodetector method

Reducing carbon dioxide (CO₂) emissions is an important strategy used to curb global warming. Notably, urban areas contribute to the majority of global CO₂ emissions. The exploration of spatial differences and their impacts on CO₂ emissions in cities serves an essential role in formulating regional carbon emission reduction strategies. Therefore, combining spatial autocorrelation analysis with a geographical detector model could help understanding how CO₂ emissions are spatially distributed in cities and the mechanisms responsible for their distribution. By analyzing China’s prefecture-level cities as spatial unit, the spatial distribution features of CO₂ emissions were investigated, and their main drivers in 2005 and 2012 were identified. The results indicates that CO₂ emissions increased by 60.35% from 2005 to 2012. The higher CO₂ emissions in cities were mainly located in the east and north regions of China. CO₂ emissions had a significant positive spatial autocorrelation and an obvious phenomenon of stratification appeared in 2005 and 2012. The degree of spatial agglomeration among cities with low and high CO₂ emissions both increased. Gross domestic product (GDP), research and development (R&D), foreign direct investment (FDI), and urban built-up area were major factors affecting CO₂ emissions. Increased population density was associated with decreased CO₂ emissions, while the effect of climate types increased from 2005 to 2012. The interactions of GDP with share_ industry (the share of labour in the secondary industry), population density, and urbanization had a stronger influence on CO₂ emissions in 2005, while the interactions of GDP with FDI, climate types, and share_ industry were stronger in 2012. However, the influence of share_ industry and climate types on CO₂ emissions were only important when certain economic levels were met. The findings provide a reference for decision-makers to develop more accurate and detailed policies to reduce CO₂ emissions in Chinese cities.