21 feet (6.4 metres)

Global warming is causing the Greenland ice cap to disintegrate far faster than anyone predicted. A study of the region’s massive ice sheet warns that sea levels may – as a consequence – rise more dramatically than expected.

The implications of the research are dramatic given that Greenland holds enough ice to raise global sea levels by up to 21ft, a disaster scenario that would result in the flooding of some of the world’s major population centres, including all of Britain’s city ports.
The Independent, 17 Feb 2006