Most Polar Bears Lost By 2050

Two-thirds of the world's polar bear population could be gone by midcentury if predictions of melting sea ice hold true, the U.S. Geological Survey reported on Friday. The fate of polar bears could be even bleaker than that estimate, because sea ice in the Arctic might be vanishing faster than the available computer models predict, the geological survey said in a report aimed at determining whether the big white bear should be listed as a threatened species. "There is a definite link between changes in the sea ice and the welfare of polar bears," said Steve Amstrup, who led the research team. Arctic sea ice is already at an all-time low this year and is expected to retreat farther this month, according to the U.S. National Snow and Ice Data Center...