Warming Is Seen as Wiping Out Most Polar Bears

Two-thirds of the world’s polar bears will disappear by 2050, even under moderate projections for shrinking summer sea ice caused by greenhouse gases in the atmosphere, government scientists reported on Friday.

The finding is part of a yearlong review of the effects of climate and ice changes on polar bears to help determine whether they should be protected under the Endangered Species Act. Scientists estimate the current polar bear population at 22,000.
The report, which the United States Geological Survey released here, offers stark prospects for polar bears as the world grows warmer.

Biologists and climate scientists conclude in the report that under middle-of-the road projections for warming the bears will by midcentury be largely relegated to the Arctic archipelago of Canada and spots off the northern Greenland coast, where summer sea ice tends to persist even in warm summers like this one, a shrinking that could be enough to reduce the bear population by two-thirds.

The bears would disappear entirely from Alaska, the study said.

“As the sea ice goes, so goes the polar bear,” said Steven Amstrup, lead biologist for the survey team.

Climate Ark