Can new-type urbanization realize low-carbon development? A spatiotemporal heterogeneous analysis in 288 cities and 18 urban agglomerations in China

Cities and urban agglomerations are carriers of greenhouse gas emissions and show significant heterogeneity. China has entered a transitional period of new-type urbanization, which emphasizes high-quality and coordinated regional development. However, evidence of the spatiotemporal heterogenous effects of new-type urbanization on carbon emissions in cities, and especially in urban agglomerations are still lacking. This study estimated the new-type urbanization level and investigated its spatiotemporal heterogenous impacts on carbon dioxide emissions (CO₂) in 288 Chinese cities and 18 urban agglomerations. The results show that for each 1% increase in new-type urbanization level, the median estimation of CO₂ emissions per capita can decrease by 171.0% (46.8%,338.4%) at city-level. The inverted "U-shaped" relationships between new-type urbanization and CO₂ emissions per capita were observed in more than 60% of the cities. The average impacts of new-type urbanization and its square term of the cities which are located in urban agglomerations are estimated to be approximately 0.8 and 1.7 times of cities that are not, which indicates that cities in urban agglomerations are peaking their CO₂ emissions per capita with a higher enhancement of new-type urbanization. The results add new insights for formulating dynamic phase-to-phase carbon reduction policies and urban planning in cities and urban agglomerations.