July 22, 1980: Mount St Helens in Washington erupts. A Yellowstone caldera eruption would explode with a force a thousand times more powerfulIs The World's Largest Super-Volcano Set To Erupt For The First Time In 600,000 Years, Wiping Out Two-Thirds Of The U.S.? -- The Daily Mail
* The super-volcano beneath Yellowstone National Park in Wyoming has been rising at a record rate since 2004
It would explode with a force a thousand times more powerful than the Mount St Helens eruption in 1980.
Spewing lava far into the sky, a cloud of plant-killing ash would fan out and dump a layer 10ft deep up to 1,000 miles away.
Two-thirds of the U.S. could become uninhabitable as toxic air sweeps through it, grounding thousands of flights and forcing millions to leave their homes.
Read more ....
My Comment: Hmmmm .... such an event would definitely change the world as we know it should it happen.