External Publications

Jul 07, 2023

Changes to the Jet Stream Could Trigger Simultaneous Crop Failures Impacting Global Food Security

Corn fields wither after prolonged drought and intense heat

The study, which analyses large observational datasets and output from climate models, indicates that computer models may underestimate the risk of concurrent crop failures occurring. It finds that yields could drop as much as 7 percent in East Asia, while global food production could fall by 3 percent. This could result in commodity price spikes and exacerbate the risk of conflict and undernutrition in countries heavily reliant on imports.


The paper published in Nature Communications reveals blind spots in climate models which suggest that the likelihood of such devastating events occurring may be higher than previously assessed. Global warming not only increases the frequency and intensity of extreme weather, it can lead to more complex, unexpected risks that are harder to predict and prepare for, such as such as multiple heatwaves happening one after another or at the same time. This paper suggests that the risk climate change poses to global food supply may therefore be harder to assess and respond to than previously thought.


Simultaneous harvest failures across major crop-producing regions are a threat to global food security. Concurrent weather extremes driven by a strongly meandering jet stream could trigger such events, but so far this has not been quantified. Specifically, the ability of state-of-the art crop and climate models to adequately reproduce such high impact events is a crucial component for estimating risks to global food security. Here we find an increased likelihood of concurrent low yields during summers featuring meandering jets in observations and models. While climate models accurately simulate atmospheric patterns, associated surface weather anomalies and negative effects on crop responses are mostly underestimated in bias-adjusted simulations. Given the identified model biases, future assessments of regional and concurrent crop losses from meandering jet states remain highly uncertain. Our results suggest that model-blind spots for such high-impact but deeply uncertain hazards have to be anticipated and accounted for in meaningful climate risk assessments.


Bibliographic data

Kornhuber, Kai, and Corey Lesk. “Changes to the Jet Stream Could Trigger Simultaneous Crop Failures Impacting Global Food Security .” July 2023.

This paper was origianlly published in Nature Communications on June 4, 2023.

Cite this article: Kornhuber, K., Lesk, C., Schleussner, C.F. et al. Risks of synchronized low yields are underestimated in climate and crop model projections. Nat Commun 14, 3528 (2023). https://doi.org/10.1038/s41467-023-38906-7

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