Emergy-based comparative analysis of urban metabolic efficiency and sustainability in the case of big and data scarce medium-sized cities: A case study for Jing-Jin-Ji region (China)

This study contributes to emergy synthesis in four aspects: (1) Provide a solution to the enduring data scarcity and inconsistency problem of emergy-based urban sustainability assessment; (2) Establish the deduction method which can deduce data at larger scale to smaller scale when lacking physical data at smaller scale instead of using monetary estimates, and also the accuracy of the deduced data can be identified by using uncertainty analysis; (3) Investigate the strategically essential Jing-Jin-Ji region as a case, applying the new approach to get the data for prefectural cities and carrying out an emergy analysis. We found that the indicators, reflecting the specific development traits of each city, are well confirmed by the status quo in the region. This fact proves that our new method framework is affordable and could be extended in the future study of medium-sized cities suffering from data scarcity. (4) Demonstrate the significant gap between using money value and physical amount to calculate emergy of imported goods, proving the importance of physical amount data in the Emergy-based comparative analysis of urban metabolic efficiency and sustainability.