I was watching a show about the Yellowstone supervolcano once, though, and I remember one scientist saying that it was unlikely to ever happen again with the same magnitude because the area of magma under Yellowstone has been moving for years, albeit slowly, and will be partly under the mountains after a while, and will be less likely to erupt with the same force because it won't be under a relatively thinner area of crust. Don't know, but it sounds plausible.
We were at Yellowstone back in 2003, when they had to close some areas because they were overheating. The map of the park shows, with a dotted line, the outline of the caldera, but you don't need that to know when you've crossed the line. The land changes, and you see what looks like chalky or salty areas along with the fumeroles continually bleeding steam into the air above ground. It is truly a sight to behold!
Do you remember the Mount Saint Helens eruption in 1980? That shut down the Pacific NorthWest for 7-10 days, remember it well. These things HAPPEN, the question is the RATE, how MUCH volcanic dust is injected into the stratosphere for it to subsequently settle out over the ensuing 3-4 years. Do you remember the golden/yellow hue of the atmosphere after the Mount Pinatubo eruption?
Yellowstone is showing all the signs of an eruption with the increased activity and rising land/earthquakes. All it takes is a crack from the surface to the pluton magma chamber 5 miles down....is this the "wormwood" mentioned in the book of revelation, and the subsequent three and a half years of nuclear winter darkness that follows.
On the one hand is the "it never happens to ME" crowd and on the other hand is may 1980...