Modeling the city-level synergistic effect of low-carbon economic development in China's Yangtze River Delta

The development of a low-carbon economy has been the focus of attention from all walks of life in recent years. Using data from 41 cities in the Yangtze River Delta (YRD) from 2005 to 2019, this study constructed a low-carbon economic development coupling and coordination degree model and indicator system to measure the synergistic effect. Starting from the resource, economy, society, and innovation system, it was found that the coupling degree of low-carbon economic development in the YRD region has increased steadily. Generally, it is in a running-in period, and the improvement rate shows a high trend in the west and a low trend in the east. Also, the YRD is in a moderate incoordination stage, but the synergy effect has improved. Among these cities, Shanghai and Hangzhou had higher synergy efficiency in 2019 compared to other cities. Regarding city heterogeneity, the synergy effect of non-resource-based cities is significantly higher than that of resource-based cities but a narrowed gap. The research provides a theoretical and factual basis for the design of a path toward low-carbon economic development in the YRD region.