Independent: It's the melting of the Arctic ice, as the climate warms, that makes it possible - and you can understand why they're all piling in. In July 2008, the US Geological Survey released the first ever publicly available estimate of the oil locked in the earth north of the Arctic Circle. Scramble for hydrocarbons above the Arctic Circle: click here to download graphic (900k) It was 90 billion barrels, representing an estimated 13 per cent of the world's undiscovered oil resources. If you're an oil...