Tracing production carbon emission transfer through global value chains: Towards a top gainer principle

This study proposes the top gainer principle (TGP) and builds a calculation model based on the TGP to measure production carbon emissions transfer (PCET) in the context of global value chains. Compared with embodied carbon research, the innovative TGP model establishes a traceability mechanism based on the difference between responsibility and actual emissions from the perspective of the value chain, avoiding the endless debate between producer and consumer responsibility, which makes the TGP model more reasonable and fairer. In addition, using long-term input-output data, this study measures spatiotemporal patterns and the network evolution of global PCET. The results show that the total amount of global PCET has increased, and the regions with high outflows of PCET mainly include East Asia, North America, Central and Western Europe, and Russia. Among these regions, the United States and China accounted for the largest proportion of PCET outflow. By contrast, South America and Africa are typical low-outflow regions. From North America via central Europe, Turkey, Iran, South Asia to China, is a "W"-shaped high net outflow belt. The overall concentration of the global PCET network first decreased and then increased, and the network structure evolved into a bipolar network group with China and the United States as the core. Under the shock of the COVID-19 pandemic, the network structure showed a trend towards decentralization. This study suggests that efforts should be made to strengthen the responsibility of major countries, enhance the supervision of lead firms, establish a carbon emission transfer compensation system within value chains, and promote the development and spread of carbon emission reduction technologies to facilitate the reduction of global carbon emissions.