According to a report at the fall meeting of the American Geophysists Union that kicked off today in San Francisco, the supervolcano under Yellowstone National Park is 2 and a half times bigger than previously thought. They say, if it ever blows, that the huge pool of magma under the surface of the park represents an existential threat to the entire world.

The last time this particular volcano erupted was 640,000 years ago and the good news is that scientists believe they would be able to detect large movements of magma underneath the surface prior to an eruption possibly giving residents of Billings some warning in the very unlikely event this would occur in our lifetimes.