Decoding the dynamics and disparities of urban carbon intensity under the influence of land use and demographics from both global and local perspectives

Timely and accurate assessment of how land use and demographics affect carbon intensity (CI) variations matters to effective reduction policies. However, the interdependencies driving these effects are not yet fully understood. This study examines the spatial heterogeneity and dynamics of urban CI in China, focusing on the roles of land use patterns and demographic factors. Results show that despite an overall decline in urban CI, carbon inequality has worsened. Notably, previously narrowing regional disparities have now diverged, driven mainly by growing variations within regional clusters. There are significant spatial differentiation in urban CI, with northern regions exhibiting higher values compared to southern regions. The spatial integration of urban CI is strongly shaped by path dependency and lock-in effects, even amid persistent inter-regional competition. The endogenous effect of urban CI suggests that a 1 % increase in neighboring areas corresponds to at least a 0.5 % increase locally. The global regression demonstrates that urbanization, labor participation, and income positively affect urban CI, while aging, technological progress, industrial upgrading, and R&D investment negatively influence it, with both direct and spillover effects observed. Local regression analysis uncovers pronounced spatial heterogeneity, with land urbanization (accounting for 71.8 %) and population aging (60.9 %) emerging as the two most significant determinants in these relationships. These findings shed light on the need to integrate land use and demographic profiles into carbon abatement strategies, advocating for locally tailored interventions to effectively mitigate urban CI.