The U.N.'s climate change panel may be severely underestimating the sea-level rise caused by global warming, climate scientists, calling for swift cuts in greenhouse emissions, Reuters reported. "The sea-level rise may well exceed one metre (3.28 feet) by 2100 if we continue on our path of increasing emissions," said Stefan Rahmstorf, professor at the Potsdam Institute for Climate Impact Research. "Even for a low emission scenario, the best estimate is about one metre." Rahmstorf spoke at the International Scientific Congress on Climate Change in Copenhagen. The U.N.'s Intergovernmental Panel on Climate Change in 2007 predicted global warming would cause sea levels to rise by between 18 cm and 59 cm (7 inches and 23 inches) this century. The IPCC said at the time the estimate could not accurately take into account factors such as the melting of ice sheets in Greenland and Antarctica. Many scientists criticised the number as too conservative. "The ice loss in Greenland shows an acceleration during the last decade," said veteran Greenland researcher Konrad Steffen, director of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado, Boulder. "The upper range of sea-level rise by 2100 might be above one metre or more on a global average, with large regional differences depending where the source of ice loss occurs," he said.