A systematic assessment of provincial-level synergy between air pollution control and carbon mitigation in China

Synergistic governance of air pollution control (AP) and carbon mitigation (CM) is a pivotal strategy for China. This study evaluates provincial-level AP-CM synergistic governance performance from 2013 to 2020, using an indicator evaluation system and a coupling coordination degree model. To understand the spatially varying relationships underlying these dynamics, it compares three models’ performance, including OLS (Ordinary Least Squares), GWR (Geographically Weighted Regression), and MGWR (Multi-scale Geographically Weighted Regression). The results indicate that China’s synergistic governance performance improved significantly over the study period, primarily driven by stringent environmental policies and enhanced coordination mechanisms. Spatially, a distinct gradient was observed, where the eastern, central, and southern regions demonstrated higher synergy levels, while western regions exhibited lower levels. This evolution was shaped by the varying performances of the individual AP and CM subsystems across provinces and time periods. Moreover, driving factors such as economic development, energy utilization, the industrial production structure, and public travel modes significantly influenced the synergistic governance performance. The MGWR analysis revealed substantial spatial heterogeneity in these effects across China. The findings of this paper underscore the importance of developing locally tailored strategies that address specific contexts and spatially varying driver impacts, rather than applying a “one-size-fits-all” strategy.