You asked us, "What will happen if the volcano under Yellowstone erupts?"
Bubbling just a few miles below the surface of Yellowstone National Park is one of the world's largest active volcanic systems and over the last 2 million years or so, it has erupted 3 times in catastrophic explosions, spewing lava and hurtling ash and gases thousands of miles away. So what's the likelihood of that kind of super eruption happening again anytime soon?
Um, not high. Estimates from the U.S. Geological Survey put it at about 1 in 730,000.
What's much more likely is a smaller, less explosive event.
Sure, the lava would still destroy everything in its path, but it'd be relatively slow moving...nothing you couldn't outrun.
Oh, no - lava!
But if Yellowstone super erupted, well, the full impact is hard to predict, but it's pretty safe to say anything or anyone nearby would be done for, in a fiery, doomsday kind of way.
Don't count yourself lucky if you're farther out, though, because that ash cloud could travel huge distances, killing crops along the way, disrupting transportation systems, contaminating water supplies...you name it.
And if ash and sulfuric gases make it into the atmosphere, a global volcanic winter could be triggered, causing cooler temperatures and all kinds of horrible snowball effects.
But don't worry, because as I said, it's much more likely we'll be outrunning lava.