Revisiting the Environmental Kuznets Curve: Does Economic Growth Necessarily Lead to More Carbon Emissions?

Under the “dual carbon” strategy, clarifying the relationship between economic growth and carbon emissions and revealing the differences in green transition pathways among different urban tiers within the metropolitan area is of great significance for promoting regional low-carbon development. Based on panel data of prefecture-level cities in 27 national metropolitan areas in China from 2000 to 2020, this paper employs a two-way fixed effects model and a mediation effect model to test the Environmental Kuznets Curve (EKC) hypothesis and to evaluate the mediating role of industrial structure advancement. The results show that, at the national level, carbon emissions and economic growth exhibit a significant inverted U-shaped relationship, but the EKC becomes invalid in non-core cities after dividing the sample into core and non-core cities. Industrial structure advancement significantly curbs carbon emissions in core cities, while its effect is insignificant in non-core cities, indicating insufficient structural transformation capacity. The findings suggest that core cities have initially formed a “structure-embedded” emission reduction pathway, whereas non-core cities face a dual challenge of growth and emission reduction. In terms of policy, excessive reliance on the “automatic decoupling of growth” should be avoided, and a differentiated governance system centred on structural transformation capacity should be established, with particular attention to enhancing the green transition capacity of non-core cities so as to promote regionally equitable and coordinated low-carbon development.