How does global transport sector improve the emissions reduction performance? A demand-side analysis

Transport sector is one of the main global carbon emitters. Its production-side aggregated carbon intensity (i.e., the ratio of carbon emissions to GDP, AI) has been well explored, but its demand-side aggregated embodied carbon intensity (i.e., the ratio of embodied emissions to embodied value added, AEI) is always ignored, which is not conducive to improving its demand-side emissions reduction performance. Thus, using the latest world input–output table from EXIOBASE, this paper adopts the environmentally extended multi-regional input–output model and the structural path analysis model to investigate this issue from the views of globe, region, transmission layer, and final demand structure, respectively. The results indicate that: first, the AEI and AI of global transport sector contribute to global AI with 4.2% and 6.7%, respectively. The AI of global transport sector is chiefly contributed by water transport and air transport, followed by land transport, while its AEI is mainly contributed by land transport, followed by water transport and air transport. Second, transport sector highly contributing to regional AEI are mostly from the developed regions in Europe. Land transport, water transport, and air transport highly contributing to the AEI of regional transport sector are generally from the regions with low AEI of transport sector, the coastal regions, and the developed regions in Europe, respectively. Finally, the critical transmission layers of the AEI of regional transport sector have great differences in various regions, but their critical final demands are similar.