数字经济促进碳减排的效应及机制

Effects and mechanisms of the digital economy for carbon emission reduction

测度了2011~2019年中国274个地级及以上城市的数字经济,并从理论和实证双重维度探讨了数字经济促进碳减排的效应及其背后的机制.结果表明:数字经济显著地降低了碳排放,数字经济每增长1%,碳排放总量和强度分别下降0.491%、0.966%.随着数字经济发展水平的提高,减排效应更加明显.这一结论在选取地形数据作为工具变量和选取“宽带中国”试点作为准自然实验等进行稳健性检验后仍然成立.此外,东部、非资源型和再生型城市能够更好地发挥数字经济红利推进碳减排;且由于人口规模和城市创新能力的不同,数字经济对碳减排的积极影响存在阈值效应.作用机制分析显示:降低能耗强度、优化产业结构、推进技术进步和数字基建赋能是数字经济实现碳减排的重要机制.数字经济每增长1%,能耗强度效应降低0.154%,而产业结构升级效应、技术进步效应及数字基建赋能效应分别增加0.835%、1.032%、0.351%.

In this paper,the digital economy of 274 prefecture-level and above cities in China from 2011 to 2019 was measured,and the effect of the digital economy on carbon emission reduction and the mechanisms were explored from both theoretical and empirical dimensions.The results showed that the digital economy significantly reduced carbon emissions.Specifically,for every 1% growth of the digital economy,the total and intensity of carbon emissions decreased by 0.491% and 0.966%,respectively.The positive effect of the digital economy became more and more significant over time.This conclusion still held after robustness tests such as selecting historical data as instrumental variables and selecting the"Broadband China"pilot project as a quasi-natural experiment.Eastern,non-resource and regenerative cities were better able to exploit the digital economy dividend and promote carbon emission reduction.The positive impact of the digital economy on carbon emission reduction had a threshold effect due to the difference in population size and innovation capacity of cities.The analysis of the mechanism showed that reducing energy consumption intensity,optimizing industrial structure,promoting technological progress and empowering digital infrastructure were important ways to achieve carbon emission reduction in the digital economy.For every 1% growth of the digital economy,the energy consumption intensity decreased by 0.154%,while the effects of industrial structure upgrading,technological progress and digital infrastructure empowerment increased by 0.835%,1.032% and 0.351%,respectively.