Thomas Gasser profile picture

Thomas Gasser

Senior Research Scholar

Integrated Assessment and Climate Change Research Group

Energy, Climate, and Environment

Senior Research Scholar

Exploratory Modeling of Human-natural Systems Research Group

Advancing Systems Analysis


Thomas Gasser is a senior research scholar jointly associated with the Exploratory Modeling of Human-natural Systems Research Group of the IIASA Advancing Systems Analysis Program and the Integrated Assessment and Climate Change Research Group of the Energy, Climate, and Environment Program. He coordinates the 'Earth system modeling' research theme.

Gasser's core expertise is in reduced-complexity modeling of the physical Earth system. His work focuses on improving and expanding reduced-complexity models and emulation techniques, on using these models to investigate policy-relevant aspects of climate change, and on linking physics-based emulators with the socioeconomic modeling tools available at IIASA. He is the main developer of the compact Earth system model OSCAR and a regular contributor to the Global Carbon Budget. He has also contributed to the Intergovernmental Panel on Climate Change (IPCC) Special Report on Global Warming of 1.5 °C and to the IPCC Sixth Assessment Report. He and his team are involved in a number of large-scale European projects, including Nunataryuk, CONSTRAIN, ESM2025: Earth System Models for the Future, and RESCUE (upcoming), as well as in more targeted ones such as the ERM: Medium Complexity Earth System Risk Management project.

Gasser holds a master-level diploma in multidisciplinary science from Ecole Polytechnique, another in environmental engineering from Ponts ParisTech, and a PhD in climate sciences from Universite Pierre et Marie Curie, all in France. Prior to working with IIASA, he conducted his doctoral research at the International Center for Development and Environment (CIRED) and his post-doctoral research at the IPSL Sciences Laboratory of Climate and the Environment (LSCE) in France, both on the dual topic of modeling couplings and feedbacks in the Earth system and quantifying the contribution of nations to human-induced climate change.

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Last update: 11 FEB 2022


Schenuit, F., Gidden, M.J. , Boettcher, M., Brutschin, E. , Fyson, C., Gasser, T. , Geden, O., Lamb, W.F., Mace, M. J., Minx, J., & Riahi, K. (2023). Secure robust carbon dioxide removal policy through credible certification. Communications Earth & Environment 4 (1) 349. 10.1038/s43247-023-01014-x.

Jones, M.W., Peters, G.P., Gasser, T. , Andrew, R.M., Schwingshackl, C., Gütschow, J., Houghton, R.A., Friedlingstein, P., Pongratz, J., & Le Quéré, C. (2023). National contributions to climate change due to historical emissions of carbon dioxide, methane, and nitrous oxide since 1850. Scientific Data 10 (1) e155. 10.1038/s41597-023-02041-1.

Grassi, G., Schwingshackl, C., Gasser, T. , Houghton, R.A., Sitch, S., Canadell, J.G., Cescatti, A., Ciais, P., Federici, S., Friedlingstein, P., Kurz, W.A., Sanz Sanchez, M.J., Abad Viñas, R., Alkama, R., Bultan, S., Ceccherini, G., Falk, S., Kato, E., Kennedy, D., Knauer, J., Korosuo, A., Melo, J., McGrath, M.J., Nabel, J., Poulter, B., Romanovskaya, A.A., Rossi, S., Tian, H., Walker, A.P., Yuan, W., Yue, X., & Pongratz, J. (2023). Harmonising the land-use flux estimates of global models and national inventories for 2000–2020. Earth System Science Data 15 (3) 1093-1114. 10.5194/essd-15-1093-2023.

Quilcaille, Y., Gasser, T. , Ciais, Philippe, & Boucher, Olivier (2023). CMIP6 simulations with the compact Earth system model OSCAR v3.1. Geoscientific Model Development 16 (3) 1129-1161. 10.5194/gmd-16-1129-2023.

Wang, J., Ciais, P., Gasser, T. , Chang, J., Tian, H., Zhao, Z., Zhu, L., Li, Z., & Li, W (2023). Temperature Changes Induced by Biogeochemical and Biophysical Effects of Bioenergy Crop Cultivation. Environmental Science & Technology 10.1021/acs.est.2c05253. (In Press)