Strategic emerging enterprises drive city-level carbon emission efficiency in China

Given the substantial economic and environmental challenges faced by global cities, enhancing carbon emission efficiency at the city level is critical for achieving urban carbon neutrality. In this context, strategic emerging enterprises play a dual role, not only driving economic expansion but also acting as catalysts for environmental sustainability. By analyzing time series data from 2013 to 2022, covering 1805 listed companies in 30 provinces and 293 cities across China, this study explores the relationship between the growth of strategic emerging enterprises and carbon emission efficiency at both the city and regional levels. The findings show a positive spatial correlation between the expansion of these enterprises and increased carbon emission efficiency, with clear spillover effects across neighboring regions. Specifically, 1 % increase in carbon emission efficiency in one city or province leads to corresponding increases of 0.168 % and 0.187 % in surrounding areas. Furthermore, the results reveal a "U-shaped" nonlinear relationship between strategic emerging enterprise growth and carbon emission efficiency, where efficiency initially declines before improving. These results underscore the critical importance of balancing economic expansion with decarbonization objectives at the city level, offering valuable insights for shaping city-focused carbon reduction strategies across sub-national regions.