Evaluating the Performance of Sustainable Urbanization and Its Impacts on Carbon Emissions: A Case Study of Nine Pearl River Delta Cities

China is presently placing significant emphasis on sustainable urbanization as a means to facilitate the shift towards high-quality economic development. The concept of sustainable urbanization has gained added intricacy and depth within the framework of ‘carbon peak and carbon neutrality’. A primary concern among practitioners is that while carbon emissions adhere to specific standards, the term sustainable urbanization remains vaguely defined, encompassing multifaceted objectives. The absence of a well-defined evaluative standard for sustainable urbanization creates challenges in driving comprehensive progress. Additionally, owing to the spatially heterogeneous nature of urbanization, its influence on carbon emissions can vary across different cities. This study delves into the shared factors influencing the performance of sustainable urbanization, introducing a Principal Component Analysis (PCA)-based evaluation system to gauge sustainable urbanization performance. Furthermore, we employ spatial regression analyses to explore the spatial differences in the impact of these factors on carbon emissions. Our investigation centers on data from nine cities in the Pearl River Delta, allowing for the ranking of these cities based on their sustainability performance. The outcomes reveal that the key factors influencing carbon emissions differ among cities due to variations in sustainable urbanization characteristics. Notably, our research integrates sustainable urbanization with the parameters of a low-carbon economy. In the realm of policymaking, we offer a quantifiable approach for assessing sustainable urbanization. Furthermore, we assert that cities at distinct stages of sustainable urbanization should prioritize different factors to attain carbon neutrality.