Spatiotemporal pattern of embodied carbon emissions from in-use steel stock in countries along the Belt and Road

Abstract

Embodied carbon emissions (ECE) from in-use steel stocks (IUSS) are crucial for urban sustainability and climate goals, yet relevant spatiotemporal information is still lacking. This study employs multi-source spatiotemporal data to develop a dynamic estimation method, evaluating the spatiotemporal dynamics of IUSS-ECE across 67 countries along the Belt and Road (B&R) from 1992 to 2020. The results indicate that a significant increase in IUSS in the B&R region led to a 24 GtCO₂ rise in ECE between 1992 and 2020, with 2005 marking a turning point for accelerated growth. ECE intensity per unit area increased from 3.4 to 5.9 ktCO₂/km², mainly in eastern B&R regions. Spatiotemporal analysis reveals the area convergence effect in ECE across the B&R, indicating that geographical relationships significantly influence ECE evolution. Additionally, the study emphasizes the significance of short-process steelmaking technology, clean energy supply, and promoting cross-regional resource circulation for the decarbonization of IUSS.