The nuclear winter that would ruin harvests for years

Hunger would kill more than the bombs: this is what a nuclear winter would look like

Most deaths in a nuclear war would not come from the blast. They would come months later, with empty plates. That is the conclusion of the outreach work by Dr. Ivana Nikolić Hughes, which draws on measurements of radioactive contamination in the Marshall Islands to explain what a nuclear exchange really means: explosive power, the persistence of radioactive fallout, radiation risks distributed unevenly, and a nuclear winter capable of collapsing food production worldwide.

The starting point is not theoretical. Between **1946 and 1958**, the United States detonated **67 nuclear tests** at Bikini and Enewetak. Castle Bravo, in 1954, released twice the expected yield and contaminated the inhabitants of Rongelap and the crew of a Japanese fishing boat. Decades later, teams from Columbia University — including Nikolić Hughes's — are still measuring radiation in the soil and in food above levels considered safe for living there.

Why radiation is not the biggest killer

Instinct leads us to think of radiation poisoning. The models and what was observed in Hiroshima and Nagasaki say otherwise: most immediate deaths come from the blast wave, building collapses, burns and fires. In Hiroshima, deaths from acute radiation were a small fraction of the total.

The truly lethal mechanism is a chain reaction. Firestorms in cities lift the soot that causes nuclear winter; that soot cools the planet by several degrees and sinks harvests for years. In Robock and Toon's scenarios, most mortality arrives **months or years later**, from the collapse of food production worldwide. And it affects the country that presses the button too.

The race that does not save you from hunger

Then comes the technological temptation: if bioengineering and cell repair keep advancing, couldn't we survive? The argument has an obvious flaw. No cell therapy prevents harvests from collapsing. Radiation could be treated; global food collapse, no.

Deterrence, double standards and the red button

The political backdrop is the usual one. Some argue that without the nuclear umbrella the United States would devour Russia, while others say the relationship is the other way around. Deterrence works as an argument until someone remembers that a single miscalculation — or an AI-controlled command system — is enough to turn theory into physics.

Nikolić Hughes's underlying thesis is uncomfortable and simple: understanding the physical consequences should come before any serious discussion about security and political decisions. Everything else is just chatter.

How long does it take a society to forget that the ground it stands on still measures above habitable levels?