中国选择二氧化碳强度减排目标是否合适——基于不确定性视角的分析

On Appropriateness of Choosing Intensity Target of CO_2 Emissions Reduction by China——Analysis from Perspective of Uncertainty Theory

控制二氧化碳减排成本的不确定性是制定减排政策的重要考虑因素之一。从不确定性的角度出发,比较二氧化碳排放总量目标与强度目标,如果二氧化碳排放波动与经济波动之间存在一定关联,且减排幅度足够大,采用强度目标的形式,能够通过对排放上限的调整减少减排数量的波动。实证研究发现,我国GDP偏离长期趋势1%,可能导致二氧化碳排放量偏离趋势约0.63%。我国在哥本哈根世界气候大会中提出的到2020年二氧化碳排放强度比2005年下降40%—45%的目标,与相应的总量目标相比,所带来的减排成本不确定性较小。

To control the uncertainty of the costs of CO2 emissions reduction is one of the key considera tions for the establishment of mitigation policy. The paper compares the total emission target with the intensity target from perspective of uncertainty theory. It is found that if there is some link between the fluctuation in e missions and the fluctuation in GDP and range of the emissions reduction is large enough, the intensity target can lower the fluctuation of the emissions reduction quantity through adjustment of the emissions ceilings. The empirical study shows that in China, if the GDP deviates from its longterm trend by 1%, the CO2 emissions may deviate from the trend by 0.63%. Under this correlation, the intensity target, to make the CO2 emission intensity drop by 40% to 45% from 2005 to 2020, proposed by Chinese government in Copenhagen Conference in 2009 will bring a smaller uncertainty in emissions reduction costs, compared to a corresponding fixed target