综合交通运输系统碳排放预测的不确定性分析

Uncertainty analysis of future carbon emissions of integrated transportation system

综合交通运输系统碳排放是全社会碳排放的主要组成部分,由于受多种因素影响,碳排放的预测具有不确定性。本文将综合交通运输系统划分为道路运输、轨道运输、水路运输和航空运输,将运输量、运输结构、运输工具的能耗和燃料的碳排放系数作为碳排放的影响因素,采用基于活动水平的方法测算综合交通运输系统碳排放。提出单位因素变化的碳排放变化率为敏感性系数,分析运输量、运输结构等不确定因素变化对碳排放的影响;设置不同减排情景,采用蒙特卡罗模拟预测在不同减排政策下碳排放发展的不确定性。通过敏感性分析研究发现:传统能源私家车、货车的运输量或能耗的变化对碳排放影响较大,敏感性系数达到0.46和0.23。不确定性分析结果表明:在既有政策设定情景和面向碳达峰情境下,交通碳排放有望在2033和2031年实现达峰,峰值分别约为11.4亿t与11.3亿t,不确定范围约为10~12亿t,随着时间的推移,碳排放的不确定范围呈扩大趋势。总体上看,交通运输系统在2030年前实现碳达峰难度较大。近中期,传统燃油车的能效提升对碳减排非常重要;中远期,推广新能源车辆措施会发挥更加重要的减排作用。

The carbon emissions of the integrated transport system are the main component of the carbon emissions of the entire society,and the prediction of carbon emissions is uncertain because of the influence of many factors.In this study,the integrated transport system was divided into road,rail,waterway,and air transport.The transport volume,transport structure,energy consumption of transport vehicles,and carbon emission coefficient of fuel were selected as the influencing factors of carbon emissions.An activity-level-based approach was adopted to calculate the carbon emissions of the integrated transport system.The rate of carbon emissions per unit factor was proposed as a sensitivity coefficient to analyze the influence of each factor on carbon emissions.The Monte Carlo simulation method predicted the uncertainty in carbon emission development under different emission reduction policies.Through sensitivity analysis,it was found that the change in transport volume or energy consumption of private cars and diesel trucks significantly impacted carbon emissions,with the sensitivity coefficients reaching 0.46 and 0.23,respectively.The uncertainty analysis results show that under the existing policy setting and carbon peak-oriented scenarios,carbon emissions from transport are expected to peak in 2033 and 2031,with peak values of approximately 1.14 billion and1.13 billion tons,respectively,and the uncertainty range is 1~1.2 billion tons.As time progresses,the greater the forecast uncertainty,the broader the uncertainty range.Overall,it will be difficult for transport systems to peak their carbon emissions by 2030.In the near and medium terms,improving the energy efficiency of traditional fuel vehicles is critical for carbon emission reduction.In the medium and long term,measures to promote new energy vehicles will play an essential role in reducing emissions.