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Will polycentric cities cause more CO2 emissions? A case study of 232 Chinese cities
Wei Sha1, Ying Chen2, Jiansheng Wu1
1Key Laboratory for Urban Habitat Environmental Science and Technology, School of Urban Planning and Design, Peking University, Shenzhen 518055, China; Laboratory for Earth Surface Processes, Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
Journal of Environmental Sciences (China)
|August 22, 2020
Summary
Urban polycentricity aids China
Area of Science:
- Urban studies
- Environmental science
- Spatial analysis
Background:
- China's rapid economic development (2000-2010) led to urbanization and a shift from single-center to polycentric cities.
- Understanding urban form's impact on CO2 emission efficiency is crucial for sustainable development.
Purpose of the Study:
- To investigate the relationship between urban aggregation, polycentricity, and CO2 emission efficiency in Chinese cities.
- To provide insights for low-carbon urban planning in China.
Main Methods:
- Exploratory Spatial Data Analysis (ESDA) identified 232 urban centers.
- Urban agglomeration (COMP) and polycentricity metrics (POLYD, POLYC, POLYP) were calculated.
- Night light data quantified CO2 emissions; a mixed model analyzed impacts on CO2 emission efficiency (2000, 2010).
Main Results:
- Compact cities were mainly coastal; polycentric cities concentrated in the Yangtze River Delta and Shandong Province.
- Higher city compactness negatively impacted CO2 emission efficiency.
- Polycentric development generally improved CO2 emission efficiency, though the number of centers was not significant.
Conclusions:
- Urban compactness and multicentricity significantly influence CO2 emission efficiency.
- Promoting polycentric urban development is recommended for enhancing CO2 emission efficiency and achieving low-carbon goals.
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