Ellen Phiddian
Cosmos science journalist
Experts have predicted a “small” nuclear war would leave a quarter of a billion people without food and a large regional conflict would raise that number to five billion. But in both scenarios, the modelling predicts that Australia would be one of the few places to stay fed.
The research, which is published in Nature Food, examines how a “nuclear winter” caused by regional nuclear wars would affect food security.
The international team of researchers outline six scenarios, each based on different-sized conflicts. The smallest represents a nuclear war between India and Pakistan, based on their weapons stockpiled in 2008. The largest represents a war between the USA and Russia, with additional attacks on France, Germany, Japan, the UK, and China.
In addition to devastating death and destruction on an untold scale, each of these scenarios would vent millions of tonnes of soot into the atmosphere. This soot would cool the globe, causing crops to fail.
“The effects of soot have been observed in the past,” says co-author Dr Ryan Heneghan, a lecturer and postdoctoral fellow at Queensland University of Technology’s School of Mathematical Sciences.
“When there have been volcanic eruptions, there have been food shortages. Even from the Australian bushfires in 2019-20 there’s evidence that about a million tonnes of soot went into the southern hemisphere’s atmosphere and the southern hemisphere cooled by a fraction of a degree because of that.”
The researchers examined how much food from livestock, crops and fisheries would be lost, and compare this to how much the world needs to eat.
“We’ve all published papers looking at those individual components. This is the first paper, I think, to bring them all together with the latest modelling technology,” says Heneghan.
The researchers examined how different types of agriculture and fisheries would fare in their six different nuclear winters, with between five million and 150 million tonnes of soot injected into the atmosphere.
They compared the total calories produced in each of these scenarios with the total calories required by the world’s population.
Aside from the initial deaths from bomb blasts (estimated between 27 million and 164 million from other research), they found that within two years, between 255 million and 2.5 billion people could starve from a nuclear war between India and Pakistan. A war between the US and Russia could kill 360 million people initially, and starve a further five billion people in two years.
“At present, we know, and the model will say, there’s enough food production in the world to feed everyone,” says Heneghan.
“This would be the first time in modern history, that there hasn’t been enough food for everyone.”
Australia and New Zealand would both be exceptions. According to the modelling, both countries could continue to feed their populations.
“There’s a few reasons for that, and a few very big caveats,” says Heneghan.
The first reason is location: currently, all countries with nuclear weapons are in the Northern Hemisphere.
“It’s very unlikely that you’d have a major nuclear war in the southern hemisphere,” says Heneghan.
The second is the amount and type of food Australia grows.
“Australia is a food exporter so we produce enough food for the 25 million Australian people, and enough to export as well.
“Under all the scenarios, we assumed that countries would stop trading food and focus on feeding their own populations. And so that puts Australia at a relative advantage, because even if there were declines in our production, the models say that we still have enough productivity to feed everyone in Australia.”
Wheat – which represents 50% of Australia’s calorie intake – would also be relatively unaffected by nuclear winter and might even grow in production thanks to colder temperatures.
This does not mean that those of us in the Antipodes can relax – a nuclear conflict would still throw up other difficulties. One problem is shifting food around.
“Australia is a pretty big place, and we’re not fuel independent,” says Heneghan.
“Maybe we can grow enough food, but it’s a question of, can we get it to the cities? And that’s something we didn’t consider.”
Watch: Cosmos Briefing: The Future of Food
The paper also points out that there would likely be a refugee influx to Australia and New Zealand from nearby nations that can’t support their populations.
“You would expect that there would be people moving around the world for better conditions and then also the possibility of conflict after the war for limited resources,” says Heneghan.
The researchers point out they’re assuming food gets distributed optimally within countries, which doesn’t currently happen. They also acknowledge that they’re looking at one facet of nuclear fallout.
“We’re just looking at human production systems. But depending on the size of the war, you would also have natural systems collapsing. So those sorts of things aren’t considered,” says Heneghan.
Assumptions and predictions aside, one thing is clear from the study.
“There really is no such thing as a regional nuclear war,” says Heneghan.
“There’s conflict in the world at the moment, that’s non-nuclear, and we don’t feel the effects of it. But that wouldn’t be the case with a regional nuclear war.”