Yiyi Ju
Research Scholar
Integrated Assessment and Climate Change Research Group
Energy, Climate, and Environment Program
Research Scholar
Sustainable Service Systems Research Group
Energy, Climate, and Environment Program
Biography
Ju Yiyi works as a research scholar in the IIASA Energy, Climate, and Environment Program.At IIASA, she mainly works with the application and development of the Integrated Assessment Model (IAM) MESSAGEix. She is the main modeler responsible for providing long-term scenarios to the Network of Central Banks and Supervisors for Greening the Financial System (NGFS) since its 5th phase. She also led the draft of the Note on Key Assumptions of NGFS Long-term Scenarios.
Her research expertise extends to broader stakeholder engagement through the United Nations Environment Programme Finance Initiative (UNEP FI). She contributed detailed sectoral analysis to the UNEP FI Sector Explorer, a tool supporting financial institutions in setting science-based targets and assessing sectoral climate pathways aligned with global climate goals.
Beyond her work on financial-sector and investment modeling, she also conducts research with a focus on climate policy instruments and industrial decarbonization (explored in other EU Horizon projects such as ELEVATE and NEWPATHWAYS).
From 2021 to 2023, she was an assistant professor at the Waseda Institute for Advanced Study (WIAS) of Waseda University in Japan, focusing on the modeling of industry technologies in energy-economic and integrated assessment models. Prior to that, she worked as a project researcher and then assistant professor in the Institute for Future Initiatives (IFI) at the University of Tokyo from 2019 to 2021, mainly involved in the Japan model intercomparison project (JMIP) research activities.
She holds a PhD in international development with a focus on environmental economics from Nagoya University, Japan.
Last update: 26 NOV 2025
Publications
Guo, C., Bertram, C., Byers, E. , Edmonds, J., Fawcett, A., Fuhrman, J., George, M., Hayez, L., Ju, Y. , Kriegler, E., Lecuyer, F., Luderer, G., & van Ruijven, B. (2025). Energy investments in the NGFS long-term scenarios phase V. Network for Greening the Financial System
Hayez, L., Lecuyer, F., George, M., Ju, Y. , Arora, M., Stevanovic, M., Anz, J., Bertram, C., Edmonds, J., Fawcett, A., Fuhrman, J., Luderer, G., Piontek, F., Schleussner, C.-F. , van Ruijven, B. , Zimmer, A., & Kriegler, E. (2025). NGFS long-term scenarios, narratives and key findings: Net Zero 2050, Current Policies and Fragmented World. Network for Greening the Financial System
Ju, Y. , Anz, J., Bertram, C., Edmonds, J., Fawcett, A., Fuhrman, J., George, M., Hayez, L., Hurst, I., Kornhuber, K. , Kriegler, E., Lecuyer, F., Piontek, F., Schleussner, C.-F. , Schwind, N., Sferra, F., van Ruijven, B. , & Zimmer, A. (2025). Note on key assumptions of NGFS long-term scenarios Phase V. Note on key assumptions of NGFS long-term scenarios Phase V. Network of Greening the Financial System
Niamir, L. , Edelenbosch, O., Boza-Kiss, B. , Magalar Martins de Souza, L., Some, S., Wiese, F., Verdolini, E., Arnz, M., Butt, M.H., Cao, T., Chatterjee, S., Chen, H.-H., Ju, Y. , Kumar, P., Mastrucci, A. , Mayer, A., McCollum, D., Onishi, N., Roy, J., van Ruijven, B. , Wiedenhofer, D., Yamaguchi, Y., Zell-Ziegler, C., & Zimm, C. (2025). Mapping Demand-side Data. 10.5281/zenodo.16911130.
Ju, Y. , Cao, T., Firdaus, N., & Li, B. (2025). Endogenizing long-term material and energy demand in response to power capacity changes by model soft-linking: application to Japan. Energy Systems 10.1007/s12667-025-00724-9.