A weighting framework to improve the use of emissions scenario ensembles of opportunity
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Integrated assessment models (IAMs) produce large ensembles of socioeconomic scenarios that are used
profusely in climate change research. The Intergovernmental Panel on Climate Change (IPCC), non-governmental organisations or national climate committees often rely on ensemble statistics to identify mitigation strategies and set climate targets. A limitation of such evidence is the opportunistic nature of scenario ensembles: they are an unstructured, serendipitous collection of evidence. Drawing on concepts from physical climate science and ensemble analysis, we present a novel approach for the flexible, multidimensional weighting of emission scenario data that accounts for relevance, quality, and diversity. Our illustrative application to the latest IPCC scenario database demonstrates a reduction in dominance of highly represented models and studies, and sees net-zero emission milestones differ to those originally reported. Our framework formalises decisions otherwise made in an ad hoc manner, providing a tool contributing to the broader challenge of assessing ensembles of
opportunity.
profusely in climate change research. The Intergovernmental Panel on Climate Change (IPCC), non-governmental organisations or national climate committees often rely on ensemble statistics to identify mitigation strategies and set climate targets. A limitation of such evidence is the opportunistic nature of scenario ensembles: they are an unstructured, serendipitous collection of evidence. Drawing on concepts from physical climate science and ensemble analysis, we present a novel approach for the flexible, multidimensional weighting of emission scenario data that accounts for relevance, quality, and diversity. Our illustrative application to the latest IPCC scenario database demonstrates a reduction in dominance of highly represented models and studies, and sees net-zero emission milestones differ to those originally reported. Our framework formalises decisions otherwise made in an ad hoc manner, providing a tool contributing to the broader challenge of assessing ensembles of
opportunity.
Date Issued
2026-03-01
Date Acceptance
2026-01-15
Citation
Nature Climate Change, 2026, 16 (3), pp.305-312
ISSN
1758-678X
Publisher
Nature Research
Start Page
305
End Page
312
Journal / Book Title
Nature Climate Change
Volume
16
Issue
3
Copyright Statement
© The Author(s) 2026. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
License URL
Identifier
10.1038/s41558-026-02565-5
Publication Status
Published
Date Publish Online
2026-02-24