Top United Nations researchers are warning that polar ice caps are melting six times faster than they were in the 1990s, threatening sea level rise that will displace hundreds of millions of people by the end of the century. The Intergovernmental Panel on Climate Change says ice loss data from Greenland and Antarctica is in line with some of the most pessimistic predictions of climate change, and that even if global carbon emissions were somehow halted today, Arctic ice would continue to melt for another three decades.