Guardian: In his account of his travels to the far north, the ancient Greek explorer Pytheas recalled encountering a wall of ice and dense fog, probably in waters around Iceland. “There was no longer land or sea or air but a kind of substance concreted from all of these elements,” he wrote, adding that the water now resembled a “sea-lung”. The Future History of the Arctic by Charles Emmerson 432pp, The Bodley Head Ltd, £20.00 Buy The Future History of the Arctic at the Guardian …