Machine Learning and Global Material Models Take 2025 Graedel Prizes

The Journal of Industrial Ecology has announced the winners of the 2025 Graedel Prizes, its annual best paper awards honoring the most influential research published in the field each year. Named after Thomas Graedel, the Yale pioneer whose work helped establish industrial ecology as a discipline, the prizes recognize two winning papers annually: one with a junior first author under the age of 36 at the time of online publication, and one with a senior first author aged 36 or older. Each winning team receives free membership in the International Society for Industrial Ecology and a cash award of 750 US dollars, along with what many researchers consider the more valuable currency of recognition from one of the most rigorous communities in sustainability science.

The selection process is deliberately structured to balance technical excellence with accessibility. Papers are nominated by members of the journal’s Editorial Board or its Prize Committee, and each candidate is evaluated against three criteria: professional merit, contribution to the field, and presentation quality. The adjudication committee publishes its rules on the journal’s website, and past award announcements, stretching back to the first winners introduced in 2015, provide a record of how the discipline’s methodological frontier has shifted over the past decade, from early material flow accounting toward machine learning, Bayesian statistics, and high-resolution global spatial modeling.

Nine papers were nominated for the 2025 cycle, and their collective breadth offers a snapshot of where industrial ecology is heading. Four were research articles. Aleksandra Kim, Christopher Mutel, and Stefanie Hellweg applied machine learning to conduct a global sensitivity analysis of correlated uncertainties in life cycle assessment, addressing one of the most persistent statistical problems in environmental footprinting. Jasmine Chea and colleagues automated the mapping of chemicals through their conditions of use, a step toward faster and more scalable life cycle chemical assessment. Two further nominated papers involved high-resolution mapping of materials in building stocks: a comprehensive global analysis of material stocks in buildings by Helmut Haberl and colleagues, and a dynamic assessment of building stock turnover across Japan by Satoshi Nagata and colleagues, which traced material and flow patterns nationwide from 2003 to 2020.

The remaining five nominated papers were methods articles, reflecting the field’s intense current interest in better analytical machinery. Philipp Grimmel and colleagues demonstrated how decision-support algorithms and databases of existing material exchanges can identify optimal opportunities for industrial symbiosis in regional economies, essentially building a recommendation platform that learns from historical exchange patterns to connect urban factories. Karin Krych, Daniel Müller, and Johan Pettersen cleverly incorporated what they describe as the nature and nurture of product lifetimes into a hazard function for dynamic stock modeling, separating intrinsic durability from contextual factors that shorten or extend product use. Jing Liao and colleagues took a technically sophisticated Bayesian approach to managing uncertainty in material flow networks, using model selection to discriminate between competing network structures and to support risk-informed decisions.

Rounding out the methods nominees, Miguel Sierra-Montoya and colleagues presented WindTrace, an open-source parametric model for generating life cycle inventories of wind turbines and wind parks, allowing environmental impacts of alternative wind energy designs to be assessed before hardware is ever built. Hanspeter Wieland, Dominik Wiedenhofer, Nina Eisenmenger, Takuma Watari, and Stefan Giljum used a global physical input-output model to assess the footprint of global iron ore mining on ecosystems, linking the steel consumed in one part of the world to the land disturbed in another. Together, the nominated set demonstrates a discipline that is simultaneously becoming more computational, more spatially explicit, and more directly connected to decision-making in energy and materials policy.

The 2025 Junior Best Paper Prize was awarded to Aleksandra Kim, Christopher Mutel, and Stefanie Hellweg for their publication on global sensitivity analysis of correlated uncertainties in life cycle assessment. Kim and Mutel are affiliated with the Laboratory for Energy Systems Analysis at the Paul Scherrer Institute in Villigen, Switzerland, while Kim also works with Hellweg in the Department of Civil, Environmental and Geomatic Engineering at ETH Zurich. The paper confronts a subtle but consequential problem: life cycle assessment databases are riddled with data whose uncertainties are correlated, because the same background processes, emission factors, and measurement methods feed into many different inventory entries. Classical sensitivity analysis techniques assume independence among inputs, and when that assumption fails, they can wildly misidentify which parameters actually drive the variability in a result.

The prize committee judged the Kim paper to be highly novel, providing new insight into how correlations between data can be handled when performing a global sensitivity analysis in life cycle assessment. The committee emphasized that the work is of high scientific quality and important for the field precisely because the approach can be applied to any life cycle assessment dataset, helping analysts address the credibility and robustness of their results. In practical terms, this matters for anyone who has ever questioned whether an environmental footprint number can be trusted: the method gives analysts a principled way to rank the true sources of uncertainty even when inputs are statistically entangled. The committee also praised the paper’s organization and readability, noting that complex techniques were explained clearly and supported by effective diagrams, a reminder that even the most mathematically demanding work in this field is judged partly on how well it communicates.

The junior prize competition was described as particularly close this year, and the committee gave special mention to two runner-up papers. The first was the Bayesian model selection work by Liao and colleagues, which brings formal probabilistic reasoning to the problem of choosing among competing material flow network structures. The second was the product lifetime paper by Krych and colleagues, whose nature-and-nurture framing of survival analysis offers dynamic stock modelers a more realistic treatment of why some products endure and others fail prematurely. That two of the three most celebrated junior-authored papers are methods innovations underscores how methodological development currently defines the field’s intellectual edge.

The 2025 Senior Best Paper Prize went to Hanspeter Wieland, Dominik Wiedenhofer, Nina Eisenmenger, Takuma Watari, and Stefan Giljum for their study assessing mining-related land footprints of global steel use with a global physical input-output model. Wieland, Wiedenhofer, and Eisenmenger are based at the Institute of Social Ecology at the University of Natural Resources and Life Sciences in Vienna, Austria. Watari works in the Material Cycles Division of the National Institute for Environmental Studies in Tsukuba, Japan, and Giljum is at the Institute for Ecological Economics at the Vienna University of Economics and Business. The paper builds on the authors’ previous global input-output model for iron and steel, but adds a decisive new layer of ecological granularity by disaggregating material flows into the specific biomes where mining takes place and by modeling both embodied land footprints and the human appropriation of net primary production.

The committee recognized many novel features in the winning senior paper. While iron ore mining is globally dominated by China, Australia, and Brazil, the authors showed that Europe holds the largest share of ecologically vulnerable tropical biomes in its embodied iron ore imports, a finding that reframes the geography of responsibility for mining-driven ecosystem damage. Rather than measuring trade in tonnes alone, the model traces exactly which ecosystems are disturbed to supply which consuming economies, connecting consumption patterns in wealthy regions to habitat loss and productivity appropriation in biodiversity-rich mining frontiers. The committee noted that the text was well written, aside from a high use of acronyms, and supported by vibrant diagrams, again rewarding technical rigor delivered with clarity.

Taken together, the 2025 Graedel Prizes highlight a discipline in methodological ascent. The winning junior paper makes uncertainty quantification in life cycle assessment more trustworthy; the winning senior paper makes the ecological consequences of the global steel economy visible at the biome scale. Around them, the nominated field is building recommendation engines for industrial symbiosis, parametric inventories for wind energy, Bayesian tools for flow networks, and continent-scale maps of the materials locked in buildings. For a field founded on the idea that human industry should be understood as an integrated system within the biosphere, the current generation of prize-recognized work shows that vision becoming operational: quantified, spatialized, and increasingly ready to inform real environmental decisions.

Subject of Research: The 2025 Graedel Prizes recognizing the best junior and senior first-authored papers in the Journal of Industrial Ecology.

Article Title: Winners of the 2025 Graedel Prizes: The Journal of Industrial Ecology Best Paper Prizes

Article References: Winners of the 2025 Graedel Prizes: The Journal of Industrial Ecology Best Paper Prizes. (n.d.). https://doi.org/10.1007/s44498-026-00165-2

Image Credits: AI Generated

DOI: 10.1007/s44498-026-00165-2

Keywords: Graedel Prizes, industrial ecology, life cycle assessment, sensitivity analysis, material flow analysis, steel land footprint, input-output model, industrial symbiosis, product lifetimes, building material stocks, wind energy, Journal of Industrial Ecology