Climate policies that fight warming may also fight hunger - but only by 15%

Climate mitigation is supposed to save the planet. But it has an uncomfortable side effect: it can make food more expensive. Carbon pricing, bioenergy production, and afforestation all compete for agricultural land, driving up commodity prices and pushing food further out of reach for the world's poorest populations.

A new study involving researchers from the University of Tokyo, Ritsumeikan University, Kyoto University, and collaborators across multiple countries quantifies both the problem and a partial solution hiding inside the same policies. The mitigation measures that raise food prices also reduce emissions of ozone precursors, lowering ground-level ozone concentrations and boosting crop yields. The question is whether that agricultural benefit meaningfully offsets the hunger cost.

The answer: partially. About 15%.

The baseline - fewer hungry people by 2050

Under a middle-of-the-road development scenario (SSP2) where current climate and air pollution conditions persist, global hunger is projected to decline. The multi-model median from six global agroeconomic models estimates that food availability will increase enough by 2050 to reduce the number of people at risk of hunger by approximately 390 million, bringing the global total to roughly 330 million.

This improvement reflects expected economic growth, agricultural productivity gains, and demographic shifts - not any specific climate intervention.

Mitigation makes food more expensive

Introducing the 1.5-degree climate target scenario changes the calculation. Carbon pricing and other mitigation measures substantially raise production costs and agricultural commodity prices - to a greater degree than even the warming scenario itself. The result: food availability drops, and by 2050, approximately 56 million more people are projected to be at risk of hunger compared to the no-mitigation baseline.

This is the central paradox of ambitious climate policy. The measures needed to prevent catastrophic warming create their own casualties, concentrated among populations that contribute least to emissions and have the fewest resources to adapt.

Ozone reduction as a hidden dividend

But climate mitigation doesn't just reduce greenhouse gases. The same policies cut emissions of ozone precursors - nitrogen oxides, volatile organic compounds, and other pollutants that react in the atmosphere to form ground-level ozone. Tropospheric ozone is toxic to crops, reducing yields of wheat, rice, soybeans, and other staples.

Lower ozone means healthier crops, higher yields, lower food prices, and greater food availability. According to the six-model analysis, this ozone dividend offsets approximately 8.4 million of the 56 million additional people pushed into hunger risk by mitigation - roughly 15% of the negative impact.

Benefits where they're needed most

The geographic distribution of this benefit matters. Approximately 56% of the hunger-reducing effect of ozone decline occurs in Sub-Saharan Africa and India - the regions where hunger is currently most severe and where populations are most vulnerable to food price increases.

This concentration isn't coincidental. These regions have high baseline ozone exposure, substantial agricultural dependence, and crops that are particularly sensitive to ozone damage. When ozone drops, the yield improvements are proportionally larger where current damage is greatest.

A 15% offset is not a solution

The researchers are clear-eyed about the implications. The ozone benefit is real but modest. Previous studies may have overestimated the negative food security impacts of climate mitigation by neglecting ozone reduction, but this study confirms that stringent mitigation can still increase hunger risks substantially if land use and price effects are not actively managed.

The practical message for policymakers: climate strategies designed without explicit consideration of food security impacts will create avoidable harm. Incorporating agricultural impact assessment at the design stage of mitigation policies - not as an afterthought - is essential for limiting increases in hunger risk.

The study also highlights the importance of jointly assessing climate change, mitigation policies, and air quality changes rather than treating them as separate problems. The tradeoffs and offsetting effects embedded in climate action only become visible when all three dimensions are modeled together.

What the models don't capture

Six global agroeconomic models provide broad consensus, but they operate at scales that necessarily smooth over local realities - water access, conflict, governance failures, supply chain disruptions, and the specific agricultural practices of smallholder farmers in the most affected regions. The models also assume that the ozone reductions actually materialize, which depends on effective implementation and enforcement of mitigation policies globally.

The 56-million figure for additional hunger risk is a median estimate with substantial uncertainty across models. And the study examines 2050 as a snapshot rather than tracing the decade-by-decade trajectory of food security under different policy scenarios.

Still, the finding that climate mitigation has a built-in - if partial - mechanism for protecting food production is worth knowing. It doesn't solve the hunger problem that ambitious climate policy creates. But it reduces it, and it does so most effectively in the places where the need is greatest.