Assessing the carbon emission performance of digital greening synergistic transformation: evidence from the dual pilot projects in China

Digital greening synergistic transformation (DGST) is a new engine for achieving dual carbon targets. Using panel data from 281 Chinese cities between 2003 and 2019, this study investigates the effect and transmission mechanism of the DGST on carbon emission performance. It is based on the quasi-natural experiments of the dual pilot projects “Broadband China” and “Low-carbon City”, as well as the multi-period difference-in-difference method. The empirical findings are as follows: (1) DGST, represented by the dual pilot projects, effectively enhances carbon emission performance. Compared to the isolated “Broadband China” and “Low-Carbon City” pilot projects, establishing dual pilot projects generates a more pronounced carbon emission reduction effect through synergistic effects. (2) In terms of dynamic effects, the carbon emission reduction effect in dual pilot cities appears in the first year following initiation, indicating a certain temporal aspect to this effect. (3) Mechanism analysis reveals that the impact of DGST on carbon emission performance is channeled through two pathways: industrial structural adjustment and low-carbon technology innovation. (4) The positive impact of DGST on carbon emission performance exhibits heterogeneity, primarily present in cities with higher levels of financial technology, human capital, and new infrastructure development. It implies that the implementation of DGST necessitates adequate human, financial, and material support. In conclusion, this research contributes empirical evidence for further exploring policy synergies, offering support for achieving dual carbon targets through DGST.