Episode 86: Food and climate

Episode 86: Food and climate

Author: Tom Chivers and Stuart Ritchie October 2, 2025 Duration: 54:54

How can both of the following be true? (1) The world has record crop harvests this year; (2) climate change is ruining crop harvests and threatening food security. Does that make sense? Is it even really a contradiction?

We look into how climate change is affecting crop yields, whether positively or negatively, and try to answer the biggest question of all: do we actually have to hand it to climate change deniers who say “CO2 is plant food”?

The Science Fictions podcast is brought to you by Works in Progress magazine. You can now hear the editors of Works in Progress on their own podcast, talking to interesting people from the worlds of science, policy, technology, and history. Their most recent episode, on how traffic has ruined cities, is available at podcast.worksinprogress.co.

Show notes

* Hannah Ritchie’s new book, Clearing the Air

* Her article on record harvests in 2025

* An example of Matt Ridley making the argument that “CO2 is plant food

* Our World in Data on crop yields

* Paper on the slower growth in crop yields due to climate change

* Nature Plants paper on trees in the Amazon getting bigger over time

* 2016 paper on the effects of climate change on crops and weeds

* EarthArxiv preprint on the balance of the effects of temperature and CO2 on crop yields

* The World Bank on fertilizer use per hectare

* And on cereal yields

* China’s fertiliser use peaking in around 2015

* Less good news from Sub-Saharan Africa

* Our older episode on climate sensitivity

* Global per capita dietary data on calories consumed per day

* Emissions from different kinds of food transportation

Credits

We’re very grateful to Dr. Hannah Ritchie from the University of Oxford and Our World in Data for talking to us for this episode. Any errors are ours, not hers. The Science Fictions podcast is produced by Julian Mayers at Yada Yada Productions.



This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit sciencefictionspod.substack.com/subscribe

Every week, Tom Chivers and Stuart Ritchie pull apart the biggest arguments and most confusing claims making headlines. Science Fictions isn't just about celebrating breakthroughs; it's a necessary dive into the messy, contested, and often surprising realities of how science actually works. You'll hear them unpack heated debates, examine questionable studies, and explore why even solid research can sometimes lead to public confusion. This podcast serves as a guide through the noise, separating compelling evidence from overblown narratives. Each episode feels like a conversation with two deeply informed friends who aren't afraid to ask tough questions, offering clarity on topics that matter. For anyone curious about the stories behind the science headlines, this is an essential listen. Tune in for thoughtful analysis that goes beyond the press release, grounded in a genuine fascination with how we know what we know.
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