A supervolcano beneath Yellowstone National Park could be overdue for an eruption, according to scientists. The explosion would send ash, dust, and sulfur dioxide into the atmosphere, reflecting the sun's rays and creating a cold wave lasting several years. Crops in many areas would fail and many species of animals and plants would face extinction.
The Yellowstone volcano has erupted once every 600,000 years, and is now 40,000 years overdue, making some volcano watchers nervous. Satellite pict