Global warming also accelerates tectonic activity: earthquakes, volcanoes, landslides. It is not simply a matter of a combustible atmosphere, the land itself would no longer be stable.

The Earth's crust responds to the changing mass of water and ice that weighs on it as it is moved around the planet's surface constantly, but which escalates during periods of global warming. The pressure is considerable: 1 cubic metre of water weighs 1 ton, while the same volume of ice weighs less - 0.9 tons. As ice sheets that had pinned down volcanoes and active fault lines melt away, the Earth's crust bounces back in a process called 'isostatic uplift'. As it does so faults are reactivated and seismic activity increases.

This is well illustrated by the Sumatran Earthquake and ensuing Indian Ocean Tsumani of 2004.