Opportunities beyond net-zero CO2 for cost-effective greenhouse gas mitigation in China

Achieving net-zero CO2 emissions is the current main focus of China's carbon neutrality goal. However, non-CO2 greenhouse gases (GHGs) are more powerful climate forcers, making their emission reduction an opportunity to rapidly mitigate future warming. Here, we evaluate non-CO2 mitigation potentials, costs and climate benefits in the context of China's carbon neutrality goals. The assessment is conducted by coupling the integrated assessment model GCAM with a climate emulator. The findings indicate that mitigation technologies can largely reduce fluorinated gas emissions from industrial sectors, but longterm non-CO2 reductions of energy sector activities rely heavily on fuel switching. Furthermore, the cumulative costs of deploying non-CO2 mitigation technologies are projected to be less than 10 % of the total costs of achieving carbon neutrality from 2020 to 2060. If non-CO2 mitigation measures are included in the overall mitigation portfolio, the benefits of avoided warming would by far outweigh the total mitigation cost increase. Our results thus highlight that incorporating a wider suite of GHGs into climate change mitigation strategies can enhance the cost-effectiveness of mitigation efforts. (c) 2024 Science China Press. Published by Elsevier B.V. and Science China Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.