Does digital economy reduce urban carbon emissions intensity in China? New perspective on a nonparametric additive model

As the world’s largest carbon emitter, China faces significant pressure to reduce urban carbon emissions intensity (CEI) in order to achieve its carbon peak and carbon neutrality targets. This study examines the impact of digital economy development on CEI using panel data from 249 Chinese cities during 2010–2019. Employing fixed-effects models and nonparametric additive models, we provide evidence that digital economy development is associated with reductions in CEI at the national level. Importantly, the relationship is both nonlinear and regionally heterogeneous. While the eastern and central regions display a generally declining association between digitalization and CEI, the western region exhibits an inverted U-shaped pattern. These results suggest that the environmental impacts of digitalization vary across regions and development stages, rather than following a uniform linear trend. Furthermore, distinguishing between traditional and new-generation digital economy components reveals that the new-generation digital economy exhibits broader and more consistent carbon-reduction effects across regions, whereas the environmental impacts of the traditional digital economy are more heterogeneous. The findings highlight the stage-dependent, region-specific, and technology-specific nature of the digital-environment nexus, offering new insights into how digital transformation can contribute to urban low-carbon development.