Industrial Carbon Emission Distribution and Regional Joint Emission Reduction: A Case Study of Cities in the Pearl River Basin, China

China’s low-carbon development path will make significant contributions to achieving global sustainable development goals. Due to the diverse natural and economic conditions across different regions in China, there exists an imbalance in the distribution of carbon emissions. Therefore, regional cooperation serves as an effective means to attain low-carbon development. This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intensity (ICEI) as a crucial factor. We utilized social network analysis and Local Indicators of Spatial Association (LISA) space-time transition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin (PRB), China from 2010 to 2020. The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression. The results were as follows: 1) the overall ICEI in the Pearl River Basin is showing a downward trend, and there is a significant spatial imbalance. 2) There are numerous network connections between cities regarding the ICEI, but the network structure is relatively fragile and unstable. 3) Economically developed cities such as Guangzhou, Foshan, and Dongguan are in the center of the network while playing an intermediary role. 4) Energy consumption, industrialization, per capita GDP, urbanization, science and technology, and productivity are found to be the most influential variables in the spatial differentiation of ICEI, and their combination increased the explanatory power of the geographic variation of ICEI. Finally, through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI, the study suggests joint carbon reduction strategies, which are centered on carbon transfer, financial support, and technological assistance among cities.