A flexible multiregional input–output database for city-level sustainability footprint analysis in Japan

Abstract

Understanding environmental and social footprints at the city level through multiregional input-output (MRIO) analysis is a key to designing policy aimed at mitigating the direct and indirect impacts of a city economy on sustainability. However, since the quantity of data required is substantial, compiling city-level MRIO tables in Japan and updating them yearly involves a huge amount of labor-intensive and time-consuming work. The authors have developed a cloud-computing platform called the Japan Industrial Ecology Laboratory (IELab) that is highly flexible in terms of its sectoral and regional resolution, which enables the user to build customized Japanese MRIO tables in accordance with the user’s specific objectives. The Japan IELab embeds over 145 types of statistical information on regional economic activities, including input-output tables at the prefecture and city level. These data serve as constraints in the optimization process to build a customized MRIO table. With IELab, the user can freely select cities, sectors and years from 1894 municipalities and 4266 sectors for the years 2005 through 2016. As a case study, two MRIO tables were built at the prefecture and city levels to demonstrate the usefulness and flexibility of the system. Their validity was confirmed by comparing results with the original statistics. The prefecture-level MRIO table accurately reflected the economic structure of Japan’s 47 prefectures by identifying differentiating prefectural features, distinguishing between, for example, manufacturing-oriented and service-oriented prefectures. The city-level MRIO table appropriately characterized various economic activities and accurately reflected the locational features of a city within the prefecture. The role of stakeholders in data management and further improvement as well as possible applications of the Japan IELab, including life cycle assessment and disaster analysis, are discussed.