From the "well, we're boned!" department:
Risk of supervolcano eruption big enough to 'affect the world' far greater than thought, say scientists (The Independent)
The eruption of a “supervolcano” hundreds of times more powerful than conventional volcanoes – with the potential to wipe out civilisation as we know it – is more likely than previously thought, a study has found.
An analysis of the molten rock within the dormant supervolcano beneath Yellowstone National Park in the United States has revealed that an eruption is possible without any external trigger, scientists said.