Urban shrinkage and carbon emissions: Demand-side accounting for Chinese cities

Many cities around the globe are showing signs of shrinking. Shrinking cities, characterized by population decline and economic stagnation, pose significant challenges to sustainable urban development and carbon emission reduction. Previous research on carbon emissions in shrinking cities has predominately focused on direct emissions within urban areas, while indirect emissions linked to the cities' trade activities have remained unexplored. This study fills this research gap by systematically analyzing both direct and indirect, i.e., embodied carbon emissions in shrinking cities and examining their variations in different shrinking phases. The multi-scale input-output model is applied to quantitatively evaluate the carbon emissions embodied in final demand and multi-scale trade of 273 cities in China for 2012, 2015, and 2017. The findings reveal that shrinking cities demonstrated higher embodied carbon intensity but lower per capita emissions than their non-shrinking counterparts. The average carbon emissions embodied in provincial, domestic, and foreign trade were lower in shrinking cities compared to non-shrinking counterparts. Additionally, the energy sectors in shrinking cities contributed a larger proportion of carbon emissions across all trade levels relative to non-shrinking cities. Case studies of four typical cities in different shrinking phases illustrated diverse trends in embodied carbon emissions. This study emphasizes the imperative for tailored strategies to effectively address both the economic and environmental challenges associated with urban shrinkage.