Vetting Implicit Normativity in Climate Economics

Project Information

VINCE

Grant agreement ID: 101064890

DOI

10.3030/101064890

Project closed

EC signature date 15 July 2022

Start date 1 June 2023

End date 31 May 2025

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 172 750,08

Coordinated by

POLITECNICO DI MILANO
Italy

Periodic Reporting for period 1 - VINCE (Vetting Implicit Normativity in Climate Economics)

Reporting period: 2023-06-01 to 2025-05-31

Summary of the context and overall objectives of the project

VINCE examines the design and use of integrated assessment models (IAMs) of climate change mitigation. IAMs address important questions about climate change, exploring how human development and societal choices interact with and affect the natural world. Their aim is to provide policy-relevant insights into global environmental change and sustainable development issues. Developing IAMs often requires making a host of implicitly normative assumptions, i.e. assumptions about the values that individuals and communities ought to pursue. These assumptions are inherently subjective and uncertain, requiring a philosophical competence to assess them.

With the support of the Marie Skłodowska-Curie Postdoctoral Fellowship program, VINCE aims to develop a new methodology for managing value judgments in the context of IAM design and use. Specifically, the objectives of the project are: (i) to help IAM designers and users identify implicitly normative assumptions, and (ii) to specify a well-functioning set of stable arrangements (which includes attributions of accountability to actors and design of institutions appropriate to the respective roles) that can effectively preserve the objectivity and integrity of IAM research in light of its implicit normativity. The proposed set of arrangements must be context-sensitive, in that it must recognize the diversity of problem situations for which IAMs are employed, and action-guiding, in that it must provide recommendations regarding when and how implicit normativity in IAMs should be addressed, additionally specifying the incentive structures that should be in place for ensuring compliance by end users.

The projects's expected impacts are multiple and are increasingly relevant as catastrophic risks of climate change grow and compound with one another. The main impacts are: a) bringing ethics closer to the climate sciences, increasing interdisciplinary work at the intersection of ethics and mathematical modeling of climate change; b) bringing climate research closer to the public, showing how societal debate and values can play a role in informing the design of mitigation scenarios; c) bringing climate research closer to policy-making, showing how reliable information is compatible (under certain conditions) with the value-ladenness of the practice of designing mitigation scenarios; d) training a new generation of engineers on the issue of sustainability, through dedicated university courses and outreach activities at Politecnico di Milano.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The project has included a training phase with state-of-the-art IAMs at Politecnico, a research phase in collaboration with climate economists at the European Institute for Environment and the Economics (EIEE) in Milan, and a validation stage in the Venice Division of the Euro-Mediterranean Center for Climate Change (CMCC).

As part of the training, I have attended the following courses: a) 'Energy, Climate Models, and Scenarios', graduate course on IAM modeling by Prof. Massimo Tavoni at the School of Engineering Politecnico di Milano; b) 'ERC Grant writing', professional development course organized by Politecnico di Milano; c) 'Climate Law and Finance: Addressing Climate Change Risks in Europe', summer school organized by FERS (Future Earth Research School), part of the Euro-Mediterranean Center for Climate Change (CMCC). I have integrated this training through supervision with Prof. Valente and Prof. Tavoni. The VINCE fellowship has provided me with training about state-of-the-art IAM design and assessment methodology, with potential to contribute significantly to the shaping of the future interdisciplinary debate on climate change mitigation and adaptation.

As part of the research activities, I have collaborated closely with climate economists at Politecnico di Milano and at the European Institute for Environment and Economics (EIEE). I have studied closely some examples of integrated assessment models of climate change (including the model WITCH, hosted at the EIEE), to identify value assumptions and better understand the practices of design and assessment of IAMs. In particular, I have analyzed the role of stakeholder engagement practices in climate change modeling and how democratic engagement can (and sometimes fail) to be reflected in the equity and risk assumptions of current models. Further, I have analyzed the practice of assessing multi-model ensembles of emission scenarios as a strategy for mitigating the biases and value-laden assumptions carried by each IAM. Collaborative research activities have resulted in several outputs, including one collaborative article on ensemble methods in the IPCC (Giarola, S., Chiani, L., Drouet, L., Marangoni, G., Nappo, F., Muttarak, R., Tavoni, M. 2024. Underestimating demographic uncertainties in the IPCC synthesis process. npj Climate Action. [Nature Portfolio] 3, 71 [OA] https://doi.org/10.1038/s44168-024-00152-y) one article on methods for projection of local-level information to integrate global IAM-based assessment (Valente, G., Bobadilla, H., El Skaf, R., Nappo, F. 2024. Tales of Twin Cities: What are Climate analogues good for? European Journal for Philosophy of Science 14: 34) and one brief (Giarola, S. & Nappo, F. 2024. How demographic uncertainty is modelled in mitigation scenarios. Behind the paper: npj Climate Action (27/08/2024). https://go.nature.com/4cBuAbn). Further research outputs from the VINCE project are currently under review, having been prevented by unprecedented slowness in review processes in philosophy journals in the post-covid world.

As part of the validation activities, I have visited the Venice Division of the Euro-Mediterranean Center for Climate Change (CMCC) this February (2025), collecting feedback from climate economists concerning the outcomes of my project. We decided over a timeline for interviewing researchers involved in stakeholder engagement projects over the course of this year. For this reason, I plan to visit them again by the end of the year to complete the project's validation.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The abovementioned collaborative work (Giarola, S., et al. 2024. Underestimating demographic uncertainties in the IPCC synthesis process. npj Climate Action. 3, 71) shows that there is a persisting problem of under-representation of socio-economic assumptions in multi-IAM ensembles of emission scenarios regularly collected and assembled by the IPCC. In particular, the latest scenario ensembles by the IPCC demonstrate a consistent trend towards particularly optimistic assumptions concerning future population growth.

From a philosophical perspective, this result is important because it shows that multi-model ensembles of scenarios can still fail (despite their size) to take into account relevant dimensions of scientific uncertainty, showing that there is a problem of unmitigated 'inductive risk' (as philosophers call the risk of error in predictions about the unobserved) even in the largest multi-model ensemble exercises. Well-known philosophical arguments (e.g. Douglas 2000) connects unmitigated inductive risk with implicit value-partiality of scientific practices.

From a practical perspective, the result could play an important role in shaping decisions concerning methods for multi-model ensembles adopted in future IPCC assessments. As preparations for IPCC AR7 are ongoing, it is important to understand what methodology to adopt in light of the value-ladenness of IAM emission scenarios. In a current manuscript (under review) I critically analyze the current 'unstructured' methodology used by Working Group III of the IPCC, whereby emission scenarios produced by the scientific community are collected with no pre-determined design. I then outline two reform prospects: a 'structured' approach, which includes protocols to ensure that various dimensions of the uncertainty space are appropriately considered, and an 'open ensemble' approach, based on a living-database approach to vetting and construction of the IPCC scenario ensemble.

The potential impact of a reform of WGIII ensemble methods are large and significant. IPCC Working Group III's cyclical assessment play a crucial role in shaping global climate action on climate change, indicating constraints for global effective mitigation. Improving the methods for drawing information from IAM-based scenarios means potentially delivering climate assessments that are more informative, more reliable, and more useful to global and regional policy-making. Moreover, while our discussion is targeted at the IPCC assessment work, the methodological lessons that we raise are important for smaller sized projects, including many model inter-comparison projects in climate economics.