Discover which disaster is most likely to end life on earth.

Machine generated contents note: 1 A Very Short Introduction to the Earth 1 -- 2 Global Warming: A Lot of Hot Air? 33 -- 3 The Ice Age Cometh 65 -- 4 The Enemy Within: Super-Eruptions, Giant Tsunami, and the Coming Great Quake 93 -- 5 The Threat from Space: Asteroid and Comet Impacts 135.