Nuclear War's Potential Collapse of the Global Food System

A nuclear exchange would devastate food production via direct destruction, rapid climate cooling, and trade network failure. Models show global temperatures could drop several degrees within months, triggering a nuclear winter that could cut worldwide food output by up to 90 percent. The United States and Russia, the largest exporters, would likely be unable to produce or ship food, and U.S. yields could fall by more than 70 percent.

Bulletin of Atomic Scientists

The war in Ukraine has shown how regional conflict can disrupt global food supplies. Climate-impact research simulates how soot from a major nuclear exchange would freeze agricultural lands across Europe, the United States, Canada, and Russia for months to years, making traditional farming impossible.

Bulletin of Atomic Scientists

Projected impacts include a global food production decline of up to 90 percent, U.S. yields falling >70 percent, and Turkey losing 8 million tons of wheat imports—enough for ~30 million people for a year. Emissions scenarios span 5–150 Tg of soot; the 37 Tg case models a large India-Pakistan exchange. Australia and Brazil could retain high export capacity, but transport collapse may limit shipments.

Bulletin of Atomic Scientists

The loss of output from the United States and Russia would erase most of the current export-import matrix, leaving many nations without essential imports. Even countries spared direct destruction would face severe shortages if primary trade partners cannot deliver. Famine risk would be greatest in the Global South, where import diversification is limited.

Bulletin of Atomic Scientists

The United Nations has launched the Independent Scientific Panel on the Effects of Nuclear War to assess research gaps and advise policymakers on mitigation strategies.

Bulletin of Atomic Scientists

Some analysts warn that emphasizing survivability could erode nuclear deterrence by suggesting that catastrophic war is manageable, thereby breaking the long-standing nuclear taboo.

Bulletin of Atomic Scientists

Proposed measures include diversifying trade partners across climate zones, developing seaweed and single-cell protein, reducing reliance on biofuel crops during crises, and creating rapid trade-agreement protocols after a shock.

Bulletin of Atomic Scientists

The literature lacks precise forecasts of social consequences and trade-ban dynamics under extreme shocks. Existing trade agreements do not address catastrophic supply disruptions, leaving uncertainty about allocation when food is scarce.

Bulletin of Atomic Scientists

• “The war in Ukraine has been enough to disrupt the food system on a global scale.” — The Bulletin

Bulletin of Atomic Scientists

• “This research shows that global temperature could drop by several degrees in a matter of months.” — The Bulletin

Bulletin of Atomic Scientists

• “[1] The 37 Tg scenario used here is based on a major nuclear exchange between India and Pakistan.” — The Bulletin

Bulletin of Atomic Scientists

The UN panel will release its first comprehensive report later this year, and several nations are evaluating food-system contingency plans with international research institutes.

Bulletin of Atomic Scientists