The title of a new study by Toon et al, published this week in Science Advances, speaks volumes: “Rapidly Expanding nuclear arsenals in Pakistan and India portend regional and global catastrophe.”
The study models the potential impacts of a regional nuclear conflict and found that, given the increased size and power of their respective nuclear arsenals, the effects of a nuclear conflict between India and Pakistan would have even more catastrophic impacts than previously thought.
In a scenario where Pakistan uses 150 nuclear weapons and India uses 100 weapons on urban targets, and the two countries use an additional 85 weapons on non-urban targets, over the course of one week:
- Up to 125 million immediate deaths, killing 2.5 times as many people died worldwide in World War II.
- Smoke from the fires would trigger massive climate disruption, reducing surface sunlight by 20 to 35% and abruptly decreasing global land temperatures by 4~8˚C.
- Precipitation would be reduced from 15 to 30% globally, with even more severe regional variations: while the US Northeast and Midwest could lose up to 50% of their rainfall, rainfall would practically cease over India and Central China.
- It would take more than a decade for temperatures and precipitation to return to normal.
- The decrease in sunlight and precipitation would severely disrupt net primary production, and thereby the entire global food chain. Two billion people would be at risk of famine.