Arctic powers in Alaska for talks as pace of global warming threatens ice cap

US to host summit of polar nations as fears grow that the Earth’s frozen wastes are losing their ability to deflect harmful raysScientists in Alaska will raise the vexed issue of methane and “black carbon” pollution as they discuss tipping-point dangers posed by global warming in the Arctic.A crucial meeting of the Arctic Council, in Anchorage, comes amid evidence that the polar region is warming faster than any other place on Earth and that sea ice coverage there has shrunk by