But with the Arctic warming four times faster than the rest of the world, sea ice is melting out earlier in the summer and freezing up later in the fall. This forces bears to spend more time ...

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Two-thirds of the world's polar bears could be extinct by 2050 if greenhouse gas-fueled global warming keeps melting their Arctic sea-ice habitat. The Center has led the charge to save polar bears ...

While science has established that there is a strong connection between melting sea ice and polar bears dying off, there is no way to know for certain why this bear was on the verge of death.

University of Wyoming researchers John Whiteman and Merav Ben-David inspect a temperature logger implantation site on a polar bear on off-shore sea ice north of Prudhoe Bay, Alaska, in April 2009.