The effect of urbanization on carbon dioxide emissions efficiency in the Yangtze River Delta, China

Cities have been one of the most important areas of CO(2) emissions. It is increasingly important to research the effect of urbanization on CO(2) emissions, especially in large emerging and developing economies, due to the indispensable need for understanding the effect of urbanization on CO(2) emissions, evaluating carbon reduction tasks and providing the scientific basis for low-carbon urbanization. Utilizing a balanced panel dataset in the Yangtze River Delta (YRD), China, during the period of 2000–2010, this paper employed data envelopment analysis (DEA) window analysis and a spatial lag panel Tobit model to investigate the effect of urbanization on CO(2) emissions efficiency (the ratio of the target CO(2) emissions to the actual CO(2) emissions). The results show that the average CO(2) emissions efficiency was 0.959 in 2010, and CO(2) emissions efficiency ranged from 0.816 to 1 and exhibited spatial clustering in the region. The larger potential of CO(2) emissions reduction appeared in Zhenjiang and Yangzhou, indicating that more CO(2) emissions reduction tasks should be allocated to these two cities. Urbanization has negative effects on improving CO(2) emissions efficiency, and there is a U-curve relation between CO(2) emissions efficiency and urbanization, indicating that CO(2) emissions efficiency decreases at the early stage of urbanization, then increases when urbanization reach a high level. There is spatial spillover effect among the prefecture-level cities, suggesting that different prefecture-level governments should coordinate with each other to improve CO(2) emissions efficiency in the whole area. Gross domestic product (GDP) per capita also plays a markedly positive role in improving CO(2) emissions efficiency. This research highlights the effect of urbanization on CO(2) emissions efficiency and the importance of improving CO(2) emissions efficiency in developing countries.