Scientific American: The world's leading climate scientists kicked up a storm in 2007, when they issued their best estimates of how quickly the oceans would swell as the globe warms. The Intergovernmental Panel on Climate Change (IPCC) projected that sea levels would rise by somewhere between 18 and 59 centimetres by the last decade of this century an upper limit that seemed far too low to other scientists, given the pace of melting in Greenland and other changes. We were hugely criticized for being too conservative,...