[Simulation and Analysis of Transportation Carbon Emission Peaking Based on System Dynamics]

Carbon peaking in the transportation sector has become an important step toward achieving the double carbon goals. Based on the causal relationship among the elements of the transportation carbon emission system, a system dynamics model was constructed from four aspects: economy, population, transportation, and carbon emission. In addition, baseline, single, low-carbon, and enhanced low-carbon scenarios were set up to analyze the change trend of transportation carbon emissions in China and the transportation carbon emission reduction potential from 2021 to 2035, and corresponding suggestions were presented. The results showed that: ① Under the baseline scenario, transportation carbon emissions increased rapidly, reaching 1.388 billion tons in 2035, with an average annual growth rate of 2.32%, and the peak of transportation carbon was not achieved. ② Under the single scenario, the enhanced freight- and industrial-structure scenarios had the best emission reduction effect, with the carbon emission reduction rate in 2035 reaching 124 and 67 million tons, respectively, and the emission reduction rate reached 8.93% and 4.85%, respectively. ③ Under the low-carbon scenario, the average annual growth rate of transportation carbon emissions from 2021 to 2030 was 1.77%, and the growth rate was expected to gradually slow down after 2030, with emission reduction measures beginning to show effects. By 2035, transportation carbon emissions were projected to reach 1.196 billion tons, but the peak in transportation carbon was still not reached. ④ Under the enhanced low-carbon scenario, through more powerful emission reduction measures such as optimizing the transportation structure and industrial structure and improving the level of transportation technology, transportation carbon emissions were projected to peak in 2033, with a peak value of 1.130 billion tons. By 2035, the emission reduction rate could reach 18.94%, among which the road carbon emission reduction rate would be 26.48% under the enhanced low-carbon scenario. This is an important breakthrough for transportation carbon emission reduction. Therefore, suggestions were presented to optimize the transportation structure, improve the transportation infrastructure, promote the upgrading of industrial structure, and strengthen the research and development of transportation equipment technology.