Broadband infrastructure and urban carbon emissions: Quasi-experimental evidence from China

As the fundamental foundation of digital economy development, broadband infrastructure has a crucial role in promoting economic growth; however, the influence of broadband infrastructure on carbon emissions remains uncertain. This study examines whether broadband infrastructure is correlated with reduced urban carbon emissions, using a multiperiod difference-in-differences (DID) model with Broadband China pilot policy implementation as a quasi-natural experiment. We assess the effects of broadband infrastructure on urban carbon emissions employing a sample of 285 Chinese cities from 2008 to 2019. The findings reveal that broadband infrastructure is correlated with significantly reduced carbon emissions, indicating an average emissions reduction of 12% to 17% in pilot cities compared with nonpilot cities. Broadband infrastructure appears to have a delayed, cumulative effect on emissions reduction. Mechanism tests indicate that broadband infrastructure promotes carbon emissions reduction through industrial structure upgrading, green technology innovation, and producer services agglomeration. Regarding city heterogeneity, broadband infrastructure contributes to more carbon emissions reduction in eastern and southern cities, large cities, and resource-based cities. Our study offers some primary evidence of broadband infrastructure's influence on achieving economic growth and sustainable development.