Kaya恒等式的碳排放驱动因素分解及其政策含义的局限性

Disaggregation of Carbon Emission Drivers in Kaya Identity and Its Limitations with Regard to Policy Implications

Kaya恒等式是目前分析碳排放驱动因素的主流分析方法,在解释全球历史排放变化原因方面具有重要的作用。Kaya恒等式具有数学形式简单、分解无残差、对碳排放变化推动因素解释力强等优点,但也存在一定的局限性:第一,Kaya恒等式只能解释碳排放量流量变化,无法解释存量变化;第二,Kaya恒等式中的驱动因素多为表象驱动因素,对排放总量的实际影响难以确定;第三,利用Kaya恒等式理论得出的政策建议具有模糊性和非理性,需要结合其他因素分析检验。

The Kaya identity has been widely used to disaggregate and identify the drivers for the variations in carbon emissions, providing an important role in understanding historical emissions change at macro-level. Kaya identity, with a simple mathematical form, can decompose drivers without residuals. However there are also some limitations with respect to its policy implications. First, Kaya identity can only explain the changes in carbon emissions flow, with limited or no attention to the existing stock of carbon emissions. Second, drivers in Kaya identity are proximate and it＇s difficult to assess their actual impacts on the total emissions. Third, policy implications derived from the conclusions using Kaya identity decomposition can be fuzzy and in conflict with common understanding and practice in reality. This indicates that Kaya identity as an analytical tool requires further examination and investigation with respect to its policy implications.