By Shaye Wolf

According to alarming weather data released this week, the Arctic just experienced its warmest winter on record. This is devastating news for polar bears, who are suffering as their sea-ice habitat melts from under their paws.

Polar bears are a global-warming poster child for good reason. Their struggle provides compelling, real-time evidence of climate change. But it also puts polar bear science in the crosshairs of climate science deniers.

To mark International Polar Bear Day last week, the dubiously named Global Warming Policy Foundation climate science denial thinktank released a report by Susan Crockford that grossly misrepresents scientific research findings on polar bears.

It’s full of the same rhetoric and misinformation you can find on her blog, infamous for its popularity in the climate science denier blogosphere.

Crockford, a zooarchaeologist, has never published an article on polar bears in a peer-reviewed journal. Documents leaked in 2012 exposed that she was on the payroll of the Heartland Institute, a propaganda machine that has cashed checks from Exxon and Koch Industries.

As a scientist, I used to wonder why climate science deniers target polar bears so fiercely: Why put so much energy into trying to obscure the plight of these magnificent creatures?

But the answer is increasingly obvious.

A recent analysis published in BioScience concluded that purveyors of climate science denial, including Crockford, distort the science around polar bears to cast doubt on climate change as a whole.

Because global warming is impossible to debunk, they try to undermine the perceived legitimacy of its mascot. In doing so, they attempt to chip away at the strength and credibility of all climate science by association.

But this year’s International Polar Bear Day was a particularly awkward time to peddle climate misinformation. After all, it followed February’s record-high Arctic temperatures, record-low sea ice and devastating new polar bear data.

At the end of February, temperatures over the entire Arctic north of 80 degrees latitude surged to more than 20 degrees Celsius above normal to temperatures normally seen in May. These were the warmest temperatures ever recorded in February, shocking scientists.

At the North Pole, temperatures may have soared above freezing — as high as 2 degrees Celsius. The northernmost weather station in the world, Cape Morris Jesup at the northern tip of Greenland, experienced an unprecedented 61 hours of temperatures above freezing so far this year.

A study published in July found that since 1980, these spikes of high winter temperatures have become more common, longer- lasting, and more intense. The increase in record-breaking Arctic temperatures is linked to the disappearance of sea ice. And Arctic sea ice is melting fast — much faster than climate models predicted.

Arctic sea ice extent hit record lows during both January and February. Arctic ice cover in each month was more than 520,000 square miles below average, an area larger than the size of Texas and California combined.

A robust body of research has long established that polar bears are profoundly dependent on this Arctic sea ice for their survival — for hunting, raising their cubs, and finding mates. And that shrinking ice is already harming them.

Photo of polar bear swimming: Rob Oo via Flickr | CC 2.0

The George W. Bush administration, normally a strict adherent to the climate science denial agenda, gave the polar bear protection under the U.S. Endangered Species Act 10 years ago. It was the first time a species gained this protection solely because of threats from global warming.

But in the past year in particular we’ve seen a series of studies culminating in a troubling conclusion: climate change is hurting polar bears even faster than we predicted.

A study published a few weeks before Crockford’s report found that polar bears have much higher energy needs than previously realized. As Arctic sea ice rapidly disappears, polar bears are having a harder time hunting the calorie-rich seals they depend on for survival, making them more vulnerable to starvation and extinction.

Other studies published in the past year reveal the extent to which polar bears are struggling to survive. They are swimming longer distances in icy Arctic water as the sea ice retreats, which is more energetically costly. They are spending less time on sea ice and more time on land where they have reduced access to food. And mothers are denning more often on land and less on ice, which increases conflicts with humans.

One of the most well-studied polar bear populations — the Southern Beaufort Sea population in Alaska — declined by 40 percent over a recent 10 year period. For the bears in this population, sea-ice loss has been linked to decreases in survival, lower success in rearing cubs, decreasing body size, and increases in fasting and nutritional stress.

Although the effects of warming on some subpopulations are not yet documented, polar bear dependence on sea ice assures that unmitigated climate change endangers them all. Research indicates that the entire Arctic may be ice-free during the summer within several decades.

If sea ice loss continues unabated, studies by several different research teams estimate that polar bears will be drastically reduced across their range by mid-century, and will ultimately disappear. 

The key to saving polar bears from their grim fate is making aggressive and rapid cuts in carbon pollution. Keeping global average temperature rise below 1.5 degrees Celsius, in line with the Paris Agreement, will help preserve polar bears in many parts of their range, protect Arctic sea ice, and avoid many of the worst consequences of climate change.

At the heart of the matter is fossil-fuel production and consumption. The science is clear that keeping the vast majority of the world’s fossil fuels in the ground is necessary not only to protect the polar bear but help preserve a livable planet for the rest of us.

And the fossil-fuel lobby bankrolls climate science deniers to distract the public from exactly that.

Many people know to put reports by climate science denial propaganda outfits in the trash bin where they belong. As evidence of climate change becomes more overwhelming, their rhetoric becomes more absurd, pushing their voices deeper into the fringe.

Shaye Wolf, PhD, is the climate science director at the Center for Biological Diversity. She graduated with a bachelor’s in biology from Yale University and received a doctorate in ecology and evolutionary biology and a master’s in ocean sciences from the University of California, Santa Cruz, where she examined the effects of ocean climate change on seabird populations.

Main photo: Cheryl Strahel via Flickr | CC 2.0