Evaluation of Atmospheric Environmental Efficiency and Spatiotemporal Differences in the Yangtze River Delta Region of China

The scientific measurement of regional atmospheric environmental efficiency is an important prerequisite for achieving energy conservation, haze reduction, and regional green and high-quality development. Taking the urban agglomeration of the Yangtze River Delta region from 2012 to 2021 as the research object, the three-stage DEA model and Malmquist index are used to measure atmospheric environmental efficiency from static and dynamic perspectives and analyze spatial and temporal differences. The study found that there is still room for improvement in the atmospheric environmental efficiency of the Yangtze River Delta urban agglomeration, and pure technical efficiency is the main factor leading to overall low efficiency. Different environmental variables have different impacts on atmospheric environmental efficiency, with industrial structure having the most significant effect. Total factor productivity of the atmosphere showed a gradual increase over the study period, with technological progress playing the most important role in contributing. Observing the three types of efficiency values for each city using the mean efficiency as a critical point, except for Shanghai, each province has two or more low efficiency problems. Based on these findings, policy recommendations are proposed to further improve the level of atmospheric environmental governance in the Yangtze River Delta region.