Abstract
As cities become increasingly interconnected in production and lifestyles, metropolitan areas have become the main areas for carbon dioxide (CO2) emissions. This article is the first to investigate the potential for peak CO2 emissions in China's metropolitan areas. Specifically, this study constructs logistic growth models using time series data of CO2 emissions from 1997 to 2017 for 26 metropolitan areas. Secondly, this study combines scenario analysis and the STIRPAT model for projection. Moreover, using the grid search method, this study optimizes ridge regression's penalty term coefficient (alpha). The results show that most metropolitan areas in China entered the saturation stage of carbon emission in 2016, but it is still challenging to achieve the goal of peak carbon dioxide emission by 2030. Per capita GDP, the proportion of the secondary industry, population, and urbanization positively affects CO2 emissions, and green technology innovation negatively affects CO2 emissions. Therefore, to achieve the peak CO2 emissions target, China should develop differentiated carbon reduction strategies for metropolitan areas and focus on the optimization and upgrading of industrial structure, the improvement of green technology level, and the low carbonization of residents' lifestyles in metropolitan areas. The significance of this study is that it helps policymakers to project potential peak CO2 emission trajectories from a bottom-up perspective, and its findings provide insights into China's peak CO2 emissions pathway.