Recently, based on long‑term research and independent development of the China’s Climate Change Integrated Assessment Model (C3IAM), the research team led by Professor Wei Yiming from the Center for Energy and Environmental Policy Research / Beijing Lab for System Engineering of Carbon Neutrality at Beijing Institute of Technology has jointly developed the new‑generation C3IAM v3.0 together with Guangdong Ocean University, Guangdong University of Technology and Huazhong University of Science and Technology. Relevant research findings have been formally published. Centering on key scientific issues and decision‑making requirements in climate governance, the model delivers systematic innovations in multi‑system coupling, mechanism characterization and policy simulation, and provides tool support for tackling global climate change and advancing the dual‑carbon goals.
Climate change and its mitigation represent complex systemic issues spanning natural sciences, engineering‑technology, and socio‑economic spheres. Conventional research is often confined to single‑domain or weakly‑coupled analysis, which falls short of supporting sophisticated climate‑governance decision‑making. Breaking through this critical bottleneck, C3IAM v3.0 establishes a unified analytical framework for deep coupling between human and natural systems and addresses the challenges of complex‑system coupling. It realizes closed‑loop full‑chain simulation covering emissions, climate responses, socio‑economic impacts and policy feedback. Through multi‑module coordination and feedback mechanisms, the model can dynamically depict intricate interactions between human activities and natural systems, shifting from “fragmented analysis” toward “system‑level integration”. This breakthrough enables the model to simultaneously answer pivotal questions such as how to design emission‑reduction pathways, what are the magnitudes of climate impacts, and how to balance policy costs and benefits.
Figure 1 Schematic diagram of the overall architecture of the C3IAM v3.0 model
Targeting core issues in climate governance, C3IAM v3.0 achieves systematic innovations in multiple dimensions:
‑ Incorporating a physically‑based climate‑system module to enhance representation of climate‑response processes;
‑ Developing an optimized carbon capture and storage (CCS) model to facilitate matching between carbon sources and carbon sinks;
‑ Refined representation of economy and technology to improve multi‑scale analytical capacity;
‑ Improving the comprehensive assessment framework for climate impacts to reveal socio‑economic feedback effects;
‑ Enabling effective linkage between global and national model systems to strengthen consistency in cross‑scale analysis.
These improvements markedly boost the model’s stability and decision‑support performance under complex scenarios.
Through long‑term accumulation and iterative upgrading, C3IAM stands as a vital home‑grown integrated‑assessment tool for climate change in China. It was previously selected for the core model library of the IPCC Sixth Assessment Report. This further upgrade enhances C3IAM’s applicability for climate governance and offers robust support for delivering the dual‑carbon goals and participating in global climate governance.
The relevant paper entitled New Generation of the China’s Climate Change Integrated Assessment Model (C3IAM v3.0) and Its Applications has been published in the international journal Structural Change and Economic Dynamics. This research was supported by the Major Program and Basic Science Center Program of the National Natural Science Foundation of China, as well as the Beijing Lab for System Engineering of Carbon Neutrality.
Paper details:
Liu, L.-J., Liang, Q.-M., Yuan, X.-C., Yu, Y.-Y., Wang, H., Liu, S.-Y., Yang, B., Jiang, H.-D., Kang, J.-N., Liu, J.-X., Xu, J., Shen, W., Yu, B., Liao, H., Chen, X., Liang, S., & Wei, Y.-M. (2026). New Generation of the China’s Climate Change Integrated Assessment Model (C3IAM v3.0) and Its Applications. Structural Change and Economic Dynamics. https://doi.org/10.1016/j.strueco.2026.03.013
