04 February 2026

This briefing is based on a webinar discussion given to the AFN Network+ community on the 28th November 2025. It is written by Nina Pullman, food systems writer for AFN; the transcript has been lightly edited to paraphrase in parts. You can also watch the webinar.

About the webinar topic:
Many decisions about our food system are being made based on data and computer models, including how we should respond to climate change, what subsidies governments should provide, and what changes supermarkets should make. But how do we know if these numbers and models are reliable? When should we trust them, and when should we be asking more questions?

Transparency is often suggested as a solution, but what would that actually look like in practice? Can we imagine a world where researchers, policymakers, and practitioners share their data and models openly — combining their insights to create something more powerful than any one group could achieve alone?

Our panel brings together expertise from energy systems, astrophysics, and food system modelling. They’ll share how they build computer models to understand our food system, the practical challenges they face, and what they’ve learned about using these tools to inform real-world decisions.

Summary of key points

Key points from Paul Behrens

• Food system models vary in terms of structure and what data they require
• Data collection is limited by self reporting and variability
• Social, political or farm-specific contexts are difficult to model
• Scientific consensus can help strengthen the findings of a model

Key points from Juan Pablo Cordero

• Astrophysics has normalised open source collaborative working
• The Future Food Calculator is a new open source food system model
• Collaboration and transparency are a key aim of the Future Food Calculator
• The Future Food Calculator will be extended to include nutrition data

Key points from the audience Q&A

• Standardised reporting of assumptions would help improve clarity
• Corporate lobbying is a challenging area to model, though it is possible
• There is a mixed appetite at Defra for open source models
• Data transparency could increase evidence-based policy decisions

About Paul Behrens

Paul Behrens is a British Academy Global Professor at the Oxford Martin School at the University of Oxford. Paul’s research focuses on the implications of rapid food system transformations in a rapidly changing world. Paul is working on integrated models to assess the environmental and social impacts of such transitions on both consumers and producers. His research and writing on climate, energy, and food, has appeared in scientific journals and media outlets such as the BBC, The Guardian, Thomson Reuters, Politico, Nature Sustainability, Nature Energy, PNAS, Nature Food, and Nature Communications. Paul’s popular science book, The Best of Times, The Worst of Times: Futures from the Frontiers of Climate Science describes humanity’s current trajectory and possible futures in paired chapters of pessimism and hope, on topics including the economy, energy, land and population.

About Juan Pablo Cordero

Juan Pablo Cordero is a postdoctoral researcher in the department of environment and geography at the University of York. Juan Pablo is lead developer of the Future Food Calculator, which challenges you to choose interventions that get the UK to net zero by 2050 without reducing our self-sufficiency.

Juan Pablo brings a background in quantitative, open-source, collaborative code development from a PhD in astrophysics, and is interested in the development of scientific software, big data research, visual representation of data, predictive numerical models and the effect of measurement uncertainty on model parameter estimation.