How does ICT agglomeration affect carbon emissions? The case of Yangtze River Delta urban agglomeration in China

In light of the development of the Yangtze River Delta region's information and communication technology (ICT) agglomeration, the environmental effects of such agglomeration, particularly the greenhouse effects, cannot be ignored. Therefore, by employing a balanced dataset of 41 cities in the Yangtze River Delta region for the period 2003–2016, this paper explores how ICT agglomeration affects the region's carbon emissions. Furthermore, to investigate the affecting mechanisms, two mediating variables (i.e., technological innovation and economic scale) and a moderating variable (i.e., foreign direct investment (FDI)) are considered. The main results indicate that: (1) ICT agglomeration has a significant positive influence on carbon emissions from urban agglomeration in the Yangtze River Delta; (2) ICT agglomeration will indirectly reduce carbon emissions through the mediating effect of technological innovation, while ICT agglomeration can positively affect carbon emissions by increasing economic scale; (3) FDI has a negative moderating effect between ICT agglomeration and carbon emissions. (4) ICT agglomeration will reduce carbon emissions in cities with lower carbon emissions, while promoting effects exist in cities with higher carbon emissions; and (5) ICT agglomeration can significantly reduce carbon emissions when the level of technological innovation is greater than the threshold value. Finally, this study highlights several policy measures based on the above findings.