A representative CO2 emissions pathway for China toward carbon neutrality under the Paris Agreement's 2 C target

In 2021, China updated its nationally determined contributions (NDCs) under the Paris Agreement, which prompts a more accurate measurement of its emissions inventory and a reasonable pathway toward carbon neutrality by 2060. This study reviews the estimates using the bottom-up emissions factor method or the top-down atmospheric CO2 concentration inversion method to derive China's CO2 emissions inventory and finds that CO2 emissions from energy combustion and industrial processes in Chinese mainland range from 11.3-12.0 GtCO(2) in 2021. Based on a comprehensive review of pathways proposed by domestic and international studies and an analysis of the origins of their differences, we proposed the Tsinghua-CMA pathway that coordinates the 2 degrees C global temperature rise control target with China's current CO2 emissions status and mitigation policies. The pathway requires China's CO2 emissions to peak around 2028-2029 at about 12.8 GtCO(2), then decline steadily to about 11.2 GtCO(2) in 2035, 3.6 GtCO(2) in 2050, and 0.9 GtCO(2) in 2060. Compared to a reference scenario without updated NDCs, this pathway would result in an economic cost of about 0.9% cumulative GDP between 2020 and 2060, only 1/4-1/3 of the cost associated with pathways that align with the 1.5 degrees C target. We recommended that China improves emissions accounting by cross-validating bottom-up and top-down approaches and regularly updating the pathway toward carbon neutrality while maintaining consistency with its evolving CO2 emissions inventory, policy trends, and global CO2 emission budget updates.