Horizon - Supervolcanoes
- It is little known that lying underneath one of America's areas of outstanding natural beauty - Yellowstone Park - is one of the largest supervolcanoes in the world. The impact of a Yellowstone eruption is terrifying to comprehend - huge areas of the USA
- http://www.bbc.co.uk/science/horizon/1999/supervolcanoes_script.shtml

Supervolcanoes could trigger global freeze [BBC News]
- The threat of climate change caused by human activity could turn out to be a minor problem by comparison with a scarcely acknowledged natural hazard. Geologists say there is a real risk that sooner or later a supervolcano will erupt with devastating force
- http://news.bbc.co.uk/1/hi/sci/tech/628515.stm