Analysis of the environmental sustainability of a megacity through a cobenefits indicator system-The case of Shanghai

Abstract

Based on the synergistic control of greenhouse gas emissions and air pollution, a co-benefits indicator system was established to evaluate the co-benefits of city policies for megacities with regard to energy conservation and environmental sustainability. Shanghai was chosen as a typical case study, owing to its relatively high level of progress in terms of urbanization and its complex economic, social, and ecological development problems. In this indicator system, 23 indicators were screened, based on the driver-pressure-state-impact-response (DPSIR) framework. Economic, social, and ecological development data for Shanghai from 2005 to 2018 were collected and analyzed using an entropy method. This was followed by the application of a weighted average method to determine the indicator weights and co-benefits index (CBI) for Shanghai. The results yield variations in the weights of the indexes. The weight of the tertiary industry production proportion in the GDP was the highest, owing to the government promotional policies, whereas the weight of the annual average temperature was the smallest, as global warming only becomes significant when the time span is much longer. In such a short time span (i.e., 14years), the change in the annual average temperature is relatively insignificant. The Co-benefit Index also varied over time; it showed a growing trend over the 14 years, increasing from 0.375 in 2005 to 1.365 in 2018, i.e., a 264% increase. This indicates that the efforts taken in Shanghai and their effects were positive, overall. Four suggestions were proposed, based on the results of the analysis: a) control the amount of total energy consumption and change the energy structure to reduce carbon and air pollution emissions; b) adjust the structure of industry, especially by increasing the proportion of tertiary industries; c) increase investments in environmental protection; and d) cooperate with regional partners to limit the occurrence of acid rain. The applicability of this approach and research prospects are also discussed.