(text: QQs: could we destroy the Earth?)

Hank: So we talk about how we, the people of Earth, have the ability to destroy ourselves in a way that most species don't. What we're generally talking about when we say this is nuclear weapons and how we like "have enough nuclear weapons to destroy the Earth many times over." Well first of all good news, we couldn't do that. In terms of pure destructive force, the entire nuclear arsenal of every country on Earth, mostly concentrated in the US and Russia, is about 7,000 megatons, the equivalent of 7 [billion] tons of TNT.

Now the Chicxulub meteor impact didn't destroy the Earth or all life on Earth and it was about 14,000 times more powerful than that. 14,000 times more power than all the nuclear weapons on Earth. We truly are puny humans.

Even the relatively mild 1883 eruption of Krakatoa was four times more powerful than the most powerful fusion bomb ever designed. Basically, if every nuclear weapon on Earth simultaneously exploded right now... we would have some bad stuff happen, there would be like an increase in localized radiation, and a number of unfortunate deaths, but overall we might actually live in a safer world, especially because those bombs right now are underground in remote areas for the most part.

The most dangerous possibility and where the idea of the deadly apocalyptic nuclear winter comes from is if those bombs are actually used on cities. The bombs themselves of course would have a significant impact but the more important bit is the resulting thousands of firestorms.

Now firestorm sounds just kind of like a hyperbolic word for like a really bad fire, but it is not that. Firestorms happen when a fire is intense enough to create its own weather pattern of increased winds, which further drive the burning and destruction and they shoot soot and ash way up into the atmosphere. This is exactly what happened in Hiroshima and Nagasaki.

If that happened thousands of times around the Earth all at once, atmospheric models indicate that yes, indeed, it would be very bad. We're talking global decreases in temperatures up to 25 degrees Celsius for a few months, and then up to 6 degrees Celsius for a number of years. That would be very bad news for all of the people and also the ecosystems that we depend on. Also, having the majority of city-dwelling humans killed and all of the city-based infrastructure destroyed would be... you know, not good.

However, and I'm not saying I want to test this out, I do have confidence that some people would survive, though they would survive in a world without YouTube and air conditioning, so really, what's the point?

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