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Polar bears turn climate refugees(thehindu)

They enter land as sea ice they rely on for hunting seals is receding

: Come fall, polar bears are everywhere around this Arctic village, dozing on sand spits, roughhousing in the shallows, padding down the beach with cubs in tow and attracting hundreds of tourists who travel long distances to see them.

At night, the bears steal into town, making it dangerous to walk outside without a firearm or bear spray. They leave only reluctantly, chased off by the polar bear patrol with firecracker shells and spotlights. On the surface, these bears might not seem like members of a species facing possible extinction.

Scientists have counted up to 80 at a time in or near Kaktovik. But the bears that come to Kaktovik are climate refugees, on land because the sea ice they rely on for hunting seals is receding. The Arctic is warming twice as fast as the rest of the planet, and the ice cover is retreating at a pace that even the climate scientists who predicted the decline find startling. Much of 2016 was warmer than normal, and the freeze-up came late.

Sense of foreboding

The continuing loss of sea ice does not bode well for polar bears, whose existence depends on an ice cover that is rapidly thinning and melting as the climate warms.

As Steve Amstrup, chief scientist for Polar Bears International, a conservation organization, put it, “As the sea ice goes, so goes the polar bear.” The apex predator became the poster animal for climate change. But the effect of climate change in the shorter term is less clear cut, and a population-wide decline is not yet apparent.

Nineteen sub-populations of polar bears inhabit five countries that ring the Arctic Circle — Canada, the U.S., Norway, Greenland and Russia. Three populations are falling in number.

But six other populations are stable. One is increasing. And scientists have so little information about the remaining nine that they are unable to gauge their numbers or their health. — New York Times News Service

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