Spatiotemporal Characteristics, Driving Mechanisms, and Sustainability Implications of the Synergy Between Embodied Carbon and Air Pollution Emissions in China

As the world’s largest carbon emitter and one of the countries facing severe air pollution challenges, China is under growing pressure to promote coordinated carbon reduction and air pollution control in support of sustainable development. From the perspective of interprovincial trade-embedded emissions, this study examines the spatiotemporal evolution, regional heterogeneity, and driving mechanisms of the synergy between embodied carbon emissions and air pollution emissions across 30 provincial-level regions in China in the 2012–2017 period. The multi-regional input–output (MRIO) model and coupling coordination degree (CCD) model are used to measure embodied emissions and the synergy effect, while the stochastic impacts by regression on population, affluence, and technology (STIRPAT) and geographically and temporally weighted regression (GTWR) models are employed to identify the main driving factors and their spatiotemporal heterogeneity. The results show that the overall synergy index of embodied carbon and air pollution emissions in China showed an increasing trend, and provinces with high-quality coordination shifted southward. Low-carbon policy and technology development mainly acted as positive drivers, whereas air pollution reduction policy and energy intensity tended to exert inhibitory effects; the role of energy consumption was more conditional and stage-specific. These findings provide useful evidence for differentiated governance, coordinated air pollution and carbon reduction, and the green and low-carbon transition.