Indo-Pakistani Nuclear War Could Kill 125 Million, New Study Shows

The “Baker” explosion, with its iconic mushroom cloud, took place during the United States’ nuclear testing in the Pacific in 1946. (Wikimedia Commons)

Nuclear war between India and Pakistan could kill 50 to 125 million people and cause a global climate catastrophe, according to a new study published on October 2. 

The study, conducted by researchers from the University of Colorado Boulder and Rutgers University, deemed Indo-Pakistani relations particularly consequential and volatile because of recent military clashes, lack of compromise on territorial disputes, and densely populated urban areas. Because both countries possess around 150 nuclear missiles, their border confrontations could quickly escalate with serious global repercussions. 

The researchers considered a variety of scenarios that could provoke a nuclear war, including the misunderstanding of each other’s motives, government breakdown, and perceived conventional military attacks. The researchers assumed the war would take place in 2025, and they estimated that both countries could have about 250 warheads each at their disposal. 

Based on the aftermath of Hiroshima, Nagasaki, as well as 520 above-ground nuclear tests before 1963, the study concluded that an Indo-Pakistani nuclear war could kill up to 125 million people, more than double the number of fatalities caused by military action during World War II. Furthermore, the explosions could ignite fires that release 16 to 35 million tons of soot into the atmosphere, blocking sunlight and cooling the Earth by 3.6°F to 9°F. Agricultural productivity would drop by 15 to 30 percent, resulting in worldwide starvation. 

"An India-Pakistan war could double the normal death rate in the world," said Brian Toon, a coauthor of the study at UC-Boulder. "This is a war that would have no precedent in human experience."

The study comes in light of recent tensions in Kashmir, a province in between India and Pakistan that has been the subject of intense territorial disputes since the two countries were partitioned in 1947. The region has sparked three conventional wars between the two regional powers, and despite a 2003 ceasefire, violent skirmishes are frequent near the border. This February, a terrorist attack in Kashmir killed 40 Indian soldiers. The incident quickly escalated into an aerial battle, during which Pakistani forces captured an Indian pilot. 

Due to the continued violence in the region, New Delhi has revoked Article 370 of the Indian Constitution, which grants a semi-autonomous status to its part of Kashmir. The heavily militarized province remains under lockdown. 

Pakistan’s prime minister recently condemned New Delhi for stripping away the semi-autonomous status of Indian-administered Kashmir and called for global intervention. 

“If a conventional war starts, anything could happen,” he said in an address to the UN General Assembly on September 27. “But supposing a country seven times smaller than its neighbour is faced with a choice: either you surrender or you fight for your freedom till death. We will fight and when a nuclear-armed country fights to the end it will have consequences far beyond the borders, it will have consequences for the world.”

Alan Robock, a coauthor of the study from Rutgers University, believes that the researchers’ findings can “reinforce the need to abolish nuclear weapons.” He hopes that the world’s nine nuclear powers can all become signatories of the 2017 United Nations Treaty on the Prohibition of Nuclear Weapons. 

“They are instruments of mass genocide. And the myth of deterrence persists,” Robock said. “But if nuclear weapons were used they would have a huge impact, through climate change, on the nation using them.”