基于函数极值条件下的中国碳达峰碳中和情景分析

基于函数极值条件提出了碳达峰出现时间和需要满足的理论条件,并对主要发达国家作了验证,同时对中国现状做了分析,最后采用了基准和强化两种情景分析了中国实现2030年碳达峰后进入2060年碳中和时期的二氧化碳排放量。研究结果显示：（1）根据IPAT恒等式将碳排放函数分解成人口、人均GDP和碳强度三个因素时,碳峰值出现时间为三个因素年增长率之和由正转负的正数值年度,发达国家的历史数据证实了这一条件。（2）中国三个因素年增长率之和自2003年起已经开始降低,最近几年一直在0.01~0.02徘徊,表明总体上朝着有利于碳达峰的方向发展,同时按照三个因素的预期发展目标计算得出中国2030年碳排放峰值的上限为112.2亿t,若2021—2035年保持相同的人均GDP年均复合增长率,碳强度年均复合增长率的绝对值需要比人均GDP年均复合增长率高0.14个百分点。（3）在能源消费总量逐渐回落的前提条件下,2060年基准情景下非化石能源占比约为65%,产生的二氧化碳量约为31.4亿t,强化情景下非化石能源占比约为70%,二氧化碳排放约为26.6亿t,而碳汇和CCUS等固碳技术还存在不确定性,碳中和任务依然艰巨。实现碳达峰碳中和最终需要控制能源消费,践行低碳消费行为。

The scenario analysis of China's carbon emission peak and carbon neutrality based on extremum condition of function

To respond to global climate change, reducing carbon dioxide emissions is one of the vital goals of China's medium- to long-term development. Based on the extremum condition of function, this paper studies the theoretical conditions of carbon peak, and verifies the results based on examples of some main developed countries. It also analyzes present situation in China according to the above conditions, and finally forecasts China's carbon dioxide emissions during the process of carbon neutrality in 2060 after carbon emission peak in 2030 under baseline and enhanced scenarios. The results are shown as follows: (1) Based on an IPAT approach, carbon dioxide emission function is divided into three factors of population, per capita GDP and carbon intensity. The year of carbon peak emerges when the sum of the annual growth rates of the three factors changes from positive to negative. This conclusion has been verified by the historical data of selected main developed countries. (2) According to the historical data of China's population, per capita GDP and carbon intensity, the sum of the annual growth rates of the three factors has declined since 2003 and fluctuated between 0.01 and 0.02 in recent years, which indicates that there is a positive trend towards carbon emission peak generally. Moreover, according to the expected development goals of the three factors, the upper limit of China's carbon dioxide emission peak in 2030 is 11.22 billion tons. If the compound annual per capita GDP growth rate keeps unchanged from 2021 to 2035, the absolute value of compound annual growth rate of carbon intensity needs to be 0.14% higher than that of per capita GDP. (3) Given the premise condition that the total energy consumption decreases gradually, in 2060, the proportion of non-fossil energy is about 65% and the carbon dioxide emission is about 3.14 billion tons under the baseline scenario, while it is about 70% and 2.66 billion tons respectively under the enhanced scenario. However, carbon sequestration technologies such as carbon sink and CCUS are still uncertain, and the task of carbon neutrality is still arduous. To achieve carbon peak and carbon neutrality, it is crucial that energy consumption should be controlled and low-carbon consumption behavior should be advocated.