碳交易政策的协同减排效应

Effects of the carbon emission trading policy on collaborative emission reduction

碳减排和大气污染物减排工作是中国可持续发展的双重战略任务。碳交易政策是气候变化政策的核心议题,其关键在于通过设定排放总量控制目标,倒逼排放主体实现减排。作为调节经济发展和环境压力的市场型政策工具,碳交易政策能否对碳排放强度以及PM_(2.5)和SO_(2)等大气污染具有协同减排效应值得深入研究。该研究以2006—2018年中国276个地级市面板数据为基础,以碳交易试点政策实施作为准自然实验,运用双重差分模型进行实证研究;进一步将样本城市划分为东、中、西3个子样本,探究区域异质性,并将中介模型纳入分析框架,探究技术创新对碳交易影响温室气体和大气污染物排放的传导机制。结果表明:①碳交易政策在降低碳排放强度的同时,也能有效实现PM_(2.5)与SO_(2)协同减排;②异质性分析结果表明,碳交易政策对大气污染物和二氧化碳的减排作用大小表现为西部地区最大,中部地区其次,东部地区最小;③碳交易政策对地区降污减排的中间作用机制表现为技术创新对碳交易和碳强度、SO_(2)、PM_(2.5)的显著中介效应。这些结论表明:在城市大气环境治理中应充分发挥市场机制作用,扩大碳排放权交易制度的市场与主体范围;在全国范围内推广碳交易政策,要将区域异质性考虑在内,增强对大气污染的区域协作治理。另外,城市规划建设要以促进技术进步和提高能源利用效率为立足点,获取环境经济综合效益。研究结果为完善中国碳交易制度,优化污染物协同减排路径,实现绿色发展提供理论借鉴。

Carbon emission reduction and air pollutant emission reduction are the dual strategic tasks of China’s sustainable development.The carbon emission trading policy is the core issue of the implementation climate change policies,and its key is to set the total emission control target and force the emission subjects to achieve emission reduction.As a market-oriented policy tool to regulate economic development and relieve environmental pressure,whether the carbon trading policy has synergistic emission reduction effects on carbon emission intensity,PM_(2.5) concentration,SO_(2) and other air pollution deserves in-depth research.Based on the panel data from 276 prefecture-level cities in China between 2006 and 2018,this study,which took the implementation of the carbon trading pilot policy as a quasi-natural experiment,used the difference-in-differences model for empirical research,and further divided the sample cities into three sub samples,i.e.those in the eastern region,those in the central region,and those in the western region,to explore regional heterogeneity.And on account of this,the intermediary model was brought into the analysis framework to explore the transmission mechanism of the impact of technological innovation on carbon trading affecting greenhouse gases and air pollutants.The results showed that:①The carbon trading policy could not only reduce carbon emission intensity,but also effectively realize the coordinated emission reduction of PM_(2.5) and SO_(2).②The results of heterogeneity analysis indicated that the effect of the carbon trading policy on the emission reduction of air pollutants and carbon dioxide was the largest in the western region,the second largest in the central region,and the smallest in the eastern region.③The intermediate mechanism of the carbon trading policy on regional pollution reduction was shown by the significant intermediary effect of technological innovation on carbon trading and carbon intensity,SO_(2) and PM_(2.5).These conclusions indicate that,concerning air pollution,we should give full play to the role of the market mechanism and expand the market and the main scope of the carbon emission trading system.At the same time,we should promote the carbon trading policy nationwide,take regional heterogeneity into account and enhance regional cooperative governance of air pollution.In addition,urban construction planning should take promoting technological progress and improving energy efficiency as the foothold to obtain comprehensive economic and environmental benefits.It is hoped that the results of this study could provide a theoretical reference for improving China’s carbon trading system,optimizing the path of pollutant collaborative emission reduction and realizing green development.