Pakistani Rangers (In Black) and Indian Border Security Force Jawans participate in the flag-lowering ceremony at the Wagah border, 1 December 2008. Arif Ali/AFP/Getty

A nuclear war between India and Pakistan could cause one billion people to starve to death around the world, and hundreds of millions more to die from disease and conflicts over food.

That is the horrifying scenario being presented in London today by a US medical expert, Ira Helfand. A conference at the Royal Society of Medicine will also hear new evidence of the severe damage that such a war could inflict on the ozone layer.

“A limited nuclear war taking place far away poses a threat that should concern everyone on the planet,” Helfand told New Scientist. This was not scare mongering, he adds: “It is appropriate, given the data, to be frightened.”


Helfand is an emergency-room doctor in Northampton, Massachusetts, US, and a co-founder of the US anti-nuclear group, Physicians for Social Responsibility. In his study he attempted to map out the global consequences of India and Pakistan exploding 100 Hiroshima-sized nuclear warheads.

Global hoarding

Earlier studies have suggested that such a conflict would throw five million tonnes of black soot into the atmosphere, triggering a reduction of 1.25°C in the average temperature at the earth’s surface for several years. As a result, the annual growing season in the world’s most important grain-producing areas would shrink by between 10 and 20 days.

Helfand points out that the world is ill-prepared to cope with such a disaster. “Global grain stocks stand at 49 days, lower than at any point in the past five decades,” he says. “These stocks would not provide any significant reserve in the event of a sharp decline in production. We would see hoarding on a global scale.”

Countries which import more than half of their grain, such as Malaysia, South Korea and Taiwan, would be particularly vulnerable, Helfand argues. So, too, would 150 million people in north Africa, which imports 45% of its food. Many of the 800 million around the world who are already officially malnourished would also suffer.

Large-scale impacts on food supplies from global cooling are credible because they have happened before, Helfand says. The eruption of the Indonesian volcano Tambora in 1815 produced the “year without a summer” in 1816, causing one of the worst famines of the 19th century.

Mass starvation

The global death toll from a nuclear war in Asia “could exceed one billion from starvation alone”, Helfand concludes. Food shortages could also trigger epidemics of cholera, typhus and other diseases, as well as armed conflicts, which together could kill “hundreds of millions”.

Another study being unveiled at today’s conference suggests that the smoke unleashed by 100, small, 15 kiloton nuclear warheads could destroy 30-40% of the world’s ozone layer. This would kill off some food crops, according to the study’s author, Brian Toon, an atmospheric scientist from the University of Colorado in Boulder, US.

The smoke would warm the stratosphere by up to 50°C, accelerating the natural reactions that attack ozone, he says. “No-one has ever thought about this before,” he adds, “I think there is a potential for mass starvation.”

Such dire predictions are not dismissed by nuclear experts, though they stress the large uncertainties involved. The fallout from a nuclear war between India and Pakistan “would be far more devastating for other countries than generally appreciated,” says John Pike, director of the US think tank, globalsecurity.org. “Local events can have global consequences.”

Dan Plesch from the University of London’s School of Oriental and African Studies, agrees that everyone is at risk from a limited nuclear war. “We live in a state of denial that our fate can be determined by decisions in Islamabad and New Delhi as much as in Washington and Moscow,” he says.