POPULAR MECHANICS
What If We Blew Up All The World’s Nukes at Once?
For starters, it would be a very, very bad day for mankind.
BY KYLE MIZOKAMI
APR 1, 2019
Sometimes it’s best not to think about just how many nukes are out there.
Nuclear weapons are enormously destructive devices capable of leveling entire cities, and arguably ending human civilization in the case of an all-out nuclear exchange. But what if humankind, for some bizarre reason, decided to set all of them off at once?
The explosive yield of nuclear weapons is typically measured in kilotons, or thousand tons of TNT. The bomb dropped on Hiroshima is typically calculated at 16 kilotons, or 16,000 tons of TNT. The W-87 warhead carried by the Minuteman III intercontinental ballistic missile has a yield of 300 kilotons. The B83 nuclear freefall bomb, carried by the B-2 Spirit stealth bomber, has a yield of up to 1.2 megatons, or 1,200 kilotons. or 1,200,000 tons of TNT
Besides the huge Cold War arsenals in United States and Russia, nukes are owned by China, the United Kingdom, France, Israel, Pakistan, India, and North Korea. Altogether, there are an estimated 15,000 nuclear weapons worldwide.
Individually, each of these weapons could do incredible damage. Kurzgesagt estimates that if the world’s supply of nukes were used evenly on its large cities, the global arsenal would be enough to kill three billion people, with 1,500 nukes left over. Packed inside a single, sprawling warehouse in the South American jungle, as Kurzgesagt imagines, they collectively have the power of up to 15 Krakatoa-style volcanic eruptions.
The detonation of this super warehouse would create a fireball 31 miles across, flattening 1,864 square miles surrounding it. A mushroom cloud 30 miles high would follow. The nuclear firestorm would expand in all directions across South America (ironic and a bit unfair, considering South America is one of the few continents without nuclear weapons). It would also be followed by a nuclear winter scenario, in which particles of dust and ash sent skyward would enter the upper atmosphere, blocking sunlight and lowering temperatures globally for several years.

The Stealth carrying 1.2 megatons of TNT power