Michio Kaku seems to be the resident expert on Yellowstone's sleeping giant known as the Yellowstone Caldera, or Super Volcano. Michio Kaku says 'all you can do is run' regarding the way to survive a super-eruption from this supervolcano. This is not the classic naysayers vs. doomsdayers story based on scripture or writings. This is coming straight from the scientists.
Underneath Yellowstone National Park lies a super volcano with a magma chamber of approximately 25,000km of magma. What is not known, is how much of it is eruptable magma. The ground has been swelling in the northwest corner of Wyoming at Yellowstone National Park. In January 2011, scientists have reported that the grounds have raised as high as ten inches in some areas of Yellowstone.
Namely, The Yellowstone Caldera, or the Yellowstone Super Volcano, which is an underground magma chamber that measures about 34 miles (55 km) by 45 miles (72 km), or 1,530 square miles, and has been wakening from a long sleep.
There has been activity at Yellowstone in the past, and there is activity right now. Scientists say the supervolcano erupts every 600,000 years, and we are currently overdue at the 640,000 year mark at the time of this writing.
The problem is, scientists have no idea when it will happen, as no human being has experience with a super volcano. It could blow tomorrow, in a week, a hundred years, or a hundred thousand years. Currently, we have no way of knowing when, but we do know that it will happen.