Public defence in the field of Systems and Operations Research, M.Sc. Nadine-Cyra Freistetter

Title of the thesis: Long-term scenario modelling for sustainable climate change mitigation and adaption

Thesis defender: Nadine-Cyra Freisetter 
Opponent: Professor Michael Obersteiner, University of Oxford
Custos: Professor Ahti Salo, Aalto University School of Science

Throughout history, people have settled in the most favourable climates and environments. However, by burning fossil fuels and cutting down forests, humanity has changed the climate for current and future generations. The changing climate, in turn, is also transforming the environment.

This dissertation examines how the way we use land (for farms, forests, grazing, and buildings) can either help slow down climate change or make it worse. Its goal was to create clearer, easier-to-use tools that show how land and climate interact, so that society can make better decisions for the future. The research uses computer models and explores different possible scenarios up to the year 2100.

The results address both local and global questions. Detailed computer simulations developed in one part of the dissertation show that in Northern Europe, the season for slippery winter conditions on roads and sidewalks may become shorter but may be even more slippery as average winter temperatures rise in the future.

In the dissertation, two new open-source computer models were also developed. These models were designed to have a low resolution, allowing them to be run very fast so that a large number of scenarios can be tested in a short amount of time without the long execution times or massive computing power that big models often require in comparable studies. The results from our models reconfirm that eating fewer animal products and protecting tropical forests globally are still among the most effective ways to reduce greenhouse gas emissions from land use. Finally, we find that land and climate policies must work together: freed-up land only helps the climate if policies motivate landowners to do activities that reduce emissions. For example, freed-up pastureland (by reducing meat consumption) left idle does not provide many climate benefits. Only with investment, like planting trees, freed-up land delivers impactful climate benefits.

Overall, the dissertation concludes that effective climate action requires coordinated policies across land, energy, and climate sectors, supported by simple and transparent computer models. Its results can be used by researchers, governments, and planners to test different policies and to understand the consequences of land-use choices.

Keywords: climate change, foresight, impact forecast, optimal mitigation strategy, integrated assessment modelling

Thesis available for public display 7 days prior to the defence at Aaltodoc. 

Contact information: 
nadine.freistetter@fmi.fi 
https://orcid.org/0000-0002-6467-4624 
https://www.researchgate.net/profile/Nadine-Cyra-Freistetter-2