Carbon, as a key element in urban metabolic processes, has received increasing attention. On the basis of data from 197 Chinese cities from 2005 to 2019, we measure the urban carbon metabolism efficiency (CME) via the super-efficiency slacks-based measure (SBM) model and examines the effects and mechanisms of the low-carbon pilot policy (LCPP) on CME through the two-way fixed effect difference-in-differences (TWFE-DID) model. The results of the study reveal that the urban CME in China generally shows a zigzag upward trend, with the highest efficiency in East China, the second highest efficiency in Central China, and lower efficiency in West China and Northeast China. The implementation of the LCPP can significantly improve CME, and this conclusion holds robust significance following a comprehensive series of endogeneity and robustness examinations. Green technology innovation, industrial structure upgrading, and green finance play important intermediary roles between the LCPP and CME. The LCPP significantly enhances CME in eastern cities, non-resource-based cities, and cities with high marketization, while the impact in other regions is not significant.
Wang et al. (2026) studied this question.