Evaluation of Material-Based GHG Emissions Under COVID-19 Disruption on Redesigning Global Supply Chain Network Across TPP Countries

In recent years, global warming has become a serious problem in a global supply chain which is a series of cross-border transaction including custom duty that is a tax imposed for imported goods. In order to prevent the global warming, Green House Gas (GHG) emissions needs to be reduced throughout the supply chain. Moreover, procurement costs, material-based GHG emissions, tariff in countries are different by each country. In addition, the Trans-Pacific Partnership (TPP), which is a free trade agreement signed between 11 countries, including Japan and Malaysia, have promoted the trade in parts and products among the TPP participant countries without customs duty. Thus, the network on the global supply chain affects not only costs but also GHG emissions. On the other hand, the disruption by COVID-19 caused adverse impacts to redesign supply chains all over the world, where parts or materials are not provided from current suppliers by the disruption. Thus, the network may be reconfigured, which brings different GHG emissions in the global supply chain network before and after the disruption across TPP countries. The purpose of this study is to evaluate material-based GHG emissions under COVID-19 disruption on redesigning global supply chain network across TPP countries. Firstly, global supply chain network is modeled and formulated. Next, numerical experiments are conducted for evaluating material-based GHG emissions under disruption scenarios. Finally, the results are analyzed in terms of GHG emissions and costs. The result shows that the highest reduction ratio of the total GHG emission on a global supply chain is 58.4% compared to the baseline.