Polar Bears Will Survive If We Reduce CO2–But With Heavy Casualties

A new study says 34.25 degrees Fahrenheit is the maximum temperature allowed if we want any of those cute North Pole critters to live. Even then, prepare for a massive die-off.


If the world can get its act together and keep global warming under 1.25C (34.25F), polar bears may actually survive, says a new study published by Nature this week.

The announcement comes as a surprise and relief to researchers and activists alike. Polar bears were placed on the endangered species list in 2008 and the common viewpoint was that as the world warms, there would not be enough ice left for polar bears to live on and fetch food from. Projections indicated that the 22,000 living polar bears would dwindle to one third that amount.

But with new computer simulations, scientists at the University of Washington and the US Geological Survey in Anchorage, Alaska, are reaching a different conclusion: If greenhouse gas emissions are significantly reduced, what ice is left will be retained and lost ice may even be restored.

“The probability of extinction would now be lower than the probability that polar bear numbers will simply be reduced,” said lead researcher, Dr. Steven Amstrup, from the US Geological Survey, as reported by the Daily Mail.

Amstrup and his colleagues looked at historical patterns of how polar bears interact with their environment, as well as what would happen if particular greenhouse gas emissions, such as carbon dioxide, were substaintially reduced in the next two decades. The result indicated that by the end of the century, enough ice would remain for polar bears to survive.

“Our research offers a very promising, hopeful message, but it’s also an incentive for mitigating greenhouse gas emissions,” said University of Washington scientist, Dr. Cecilia Bitz.


Without abundant ice, polar bears are unable to perch and fetch for their primary diet of seals. Consequently, they lose two pounds per day as the ice melts and prospects for eating grow dim. And as there are fewer living members of the species alive, inter-breeding is also becoming a cause of death amongst polar bears, as the interbred offspring are frequently born with abnormalities, making them unfit to survive in the environments in which they are born.

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[Image: flickr user Alistair Rae]

About the author

Jenara is an overseas reporter for Fast Company and a freelance writer/producer in Asia, regularly on CNNGo, and a graduate of Harvard and UC Berkeley.