数字经济之于城市碳排放:“加速器”抑或“减速带”?

Digital economy development for urban carbon emissions:‘accelerator’or‘speed bump’?

在“双碳”目标引领城市绿色低碳转型发展和数字经济新时代全面到来的背景下,深入探讨数字经济对城市碳排放的影响已成为当前一项重要议题。该研究选取2011—2019年城市面板数据,基于熵权TOPSIS法测度数字经济发展水平,运用双向固定效应模型和中介效应模型实证分析数字经济对城市碳排放的影响及其作用机制。结果表明:①数字经济发展对城市碳排放的影响具有先增加后减少的倒“U”型特征,即前期具有“加速器”效果,后期表现为“减速带”作用,经过一系列稳健性检验后该结论仍成立。②机制检验发现,数字经济发展通过影响能源消耗、促进绿色技术创新和产业结构升级,进而对碳排放表现出先增加后减少的非线性影响。③异质性分析表明,数字经济对碳排放的影响因经济发展水平、资源禀赋、行政等级的不同而表现出显著性差异。④中国城市间的碳排放存在显著的空间相关性,数字经济对经济与地理邻近城市碳排放的空间溢出效应呈现出倒“U”型特征。该研究从学理上揭示了数字经济对城市碳排放的影响效果和作用机制。据此提出,各地区在强化数字经济赋能传统行业节能减排的同时,须提升自身能源利用效率,打造更具生态化的数字经济发展模式;通过产业数字化和数字产业化推动产业向低碳化的集约式转型升级,依托地区资源禀赋、城市行政等级和经济发展情况,加快推进不同类型城市数字化与绿色低碳化协同发展。

We are in an era of urban green and low-carbon transformation and digital economy motivated by the goals of reaching peak carbon emissions and carbon neutrality.In this context,an in-depth discussion of the impact of the digital economy on urban carbon emissions has become an important topic.Using the urban panel data from 2011 to 2019,this study measured the development level of the digital economy based on the entropy weight TOPSIS method and empirically analyzed the impact of the digital economy on urban carbon emissions and its mechanism by using the two-way fixed effect model ae and the mediation effect model.The results showed that:①The impact of digital economy development on urban carbon emissions had an inverted U-shaped characteristic of increasing first and then decreasing;that is,it had an‘accelerator’effect in the early stage and a‘speed bump’effect in the later stage.After a series of robustness tests,the conclusion still held.②Mechanism inspection found that the development of the digital economy showed a nonlinear impact on carbon emissions,with a characteristic of first increasing and then decreasing by affecting energy consumption and promoting green technology innovation and industrial structure upgrading.③Heterogeneity analysis indicated that the impact of the digital economy on carbon emissions showed significant differences due to differences in economic development levels,resource endowments,and administrative levels.④There was a significant spatial correlation between carbon emissions among Chinese cities,and the spatial spillover effect of the digital economy on carbon emissions in the economy and geographically adjacent cities presented an inverted U-shaped feature.This study theoretically reveals the impact of the digital economy on the effects and mechanisms of urban carbon emissions.Based on this conclusion,while strengthening the digital economy to empower traditional industries to save energy and reduce emissions,all regions must improve their own energy utilization efficiency,create a more ecological digital economy development model,and promote the intensive transformation of low-carbon industries through industrial digitization and digital industrialization.They must also rely on regional resource endowments,urban administrative levels,and economic development to accelerate the coordinated development of digitalization and green and low-carbon development in different types of cities.