Driving effects of urbanization on city-level carbon dioxide emissions: from multiple perspectives of urbanization

Cities have emerged as ‘first responders’ in carbon dioxide emission reduction. However, it is a great dilemma for cities to reach high urbanization level and achieve carbon dioxide emission reduction. Chinese cities are in high speed of urbanization process both in urban-rural population structure change and land-use change. Although there are a large body of research studies exploring urbanization-carbon dioxide emission nexus, some limitations remain. Firstly, most research studies only one-sidedly define urbanization as demographic urbanization, but fail to focus on its land-use change; secondly, present studies more tend to reveal the relationship between urbanization and carbon dioxide emissions, but do not recognize main contributors. Thus, this study aims to explore the urbanization-carbon dioxide emission nexus in South Jiang Province during 2000–2016. Panel data model and impulse response function based on a vector autoregression (VAR) model are established as the methodology framework. Expressly, urban built-up area, entire built-up area and urban road area are selected to depict land-use change in urbanization process. The results indicate that population and gross regional domestic product (GRDP) are positively correlated with carbon dioxide emissions. The entire built-up area and urban road area are positively correlated with carbon dioxide emissions, while urban built-up area is negatively correlated with carbon dioxide emissions. However, there is little evidence to support the connection between demographic urbanization and carbon dioxide emissions. It is proved that all independent variables impact CO2 emissions in the long run in South Jiangsu Province. Importantly, population and GRDP remain the main contributors of carbon dioxide emissions, compared with urbanization. As such, it is more necessary for South Jiangsu Province to control the upsurge economy and population, especially the migration population. Concentrating compact city development is also critical. These policy implications are also for other Chinese cities.