Polar bears will disappear by 2050 as Arctic sea ice melts, killer whale will be top predator

From NPR:

At the rate the sea ice is melting, by the summer of 2050, the Arctic will be a mostly open ocean.

Anderson says as the ice melts, it will take several forms of "revenge" on those living south of the Arctic.

"Once the tundra that rims the Arctic starts to thaw, what we'll see is greenhouse gases pouring out of that tundra," Anderson says. Those gases include methane and carbon dioxide, and they'll contribute to climate change, he says.

Another problem: rising sea levels. As the ice cap sitting on top of Greenland melts, it pours into the sea. Anderson says if the entire cap melts, sea levels worldwide will rise by 20 feet or more.



There are 64 polar bears in captivity in American zoos, far short of the 200 considered optimal for maintaining the population over 100 years. Source: Zoos’ Bitter Choice - To Save Some Species, Letting Others Die - NYTimes.com http://goo.gl/UiiLj -- Zoos Have to Decide Which Species to Keep - Graphic http://goo.gl/bfTlh

References:

What Happens To Polar Bears As Arctic Ice Shrinks? NPR.
Come on in, the water's freezing! Images of polar bears diving into icy pool. Daily Mail, 2011.