SEPTEMBER 8, 2007 Warming Is Seen as Wiping Out Most Polar Bears

Alaska Image Library/ Fish and Wildlife Service, via Bloomberg News A on the Beaufort coast of Alaska. Federal scientists say Alaska could lose all its polar bears if summer sea ice

By JOHN M. BRODER and stark prospects for polar bears as the The report was released as President ANDREW C. REVKIN world grows warmer. Bush was in Australia meeting with Asian leaders to try to agree on a strategy — Two-thirds of the The scientists concluded that, while to address global warming. Mr. Bush world’s polar bears will disappear by the bears were not likely to be driven will be host to major industrial nations 2050, even under moderate projections to extinction, they would be largely in Washington this month to discuss for shrinking summer sea ice caused by relegated to the Arctic archipelago the framework for a treaty on climate greenhouse gases in the atmosphere, of Canada and spots off the northern change. government scientists reported on Greenland coast, where summer sea ice Friday. tends to persist even in warm summers The United Nations plans to devote its like this one, a shrinking that could be general assembly in the fall to global The fi nding is part of a yearlong review enough to reduce the bear population warming. of the effects of climate and ice changes by two-thirds. on polar bears to help determine whether A spokeswoman for the White House they should be protected under the The bears would disappear entirely from declined to comment on the report, Endangered Species Act. Scientists Alaska, the study said. saying it was part of decision making estimate the current polar bear population at the Interior Department, parent of at 22,000. “As the sea ice goes, so goes the the survey. polar bear,” said Steven Amstrup, lead The report, which the United States biologist for the survey team. In the report, the team said, “Sea ice Geological Survey released here, offers conditions would have to be substantially better than even the most conservative The report makes no recommendation Letters, says sea-ice coverage of the computer simulations of warming and on listing the bears as a threatened Arctic Ocean will decline by more than sea ice” to avoid the anticipated drop in species or taking any action to slow ice 40 percent before the summer of 2050, bear population. cap damage. Such decisions are up to compared with the average ice extent another Interior Department agency, from 1979 to 1999. In a conference call with reporters, the the Fish and Wildlife Service, which scientists also said the momentum to a enforces the Endangered Species Act. This summer the ice retreated much warmer world with less Arctic sea ice That decision is due in January, offi cials farther and faster than in any year since — and fewer bears — would be largely have said. The wildlife agency had to satellite tracking began in 1979, several unavoidable at least for decades, no make a determination on the status of a Arctic research groups said. matter what happened with emissions threatened species because of a suit by John H. Broder reported from of heat-trapping gases like carbon environmental groups like Greenpeace dioxide. Washington, and Andrew C. Revkin and the Natural Resources Defense from New York. “Despite any mitigation of greenhouse Council. gases, we’re going to see the same In some places, the bears have adapted amount of energy in the system for 20, to eating a wide range of food like snow 30 or 40 years,” said Mark Myers, the geese and garbage. But the survey team survey director. “We would not expect said their fate was 84 percent linked to to see any signifi cant change in polar the extent of sea ice. conditions regardless of mitigation.” Separate studies of trends in Arctic sea In other words, even in the unlikely ice by academic and government teams event that all the major economies were have solidifi ed a picture of shrinking to agree to rapid and drastic reductions area in summers for decades to come. in emissions of carbon dioxide and other heat-trapping gases, the fl oating Arctic A fresh analysis by scientists of the ice cap will continue to shrink at a rapid National Oceanic and Atmospheric pace for the next 50 years, wiping out Administration, to be published Saturday much of the bears’ habitat. in the journal Geophysical Research