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We all have one thing in common: We share an interest in ensuring a future for polar bears.
We know a melting habitat is the biggest threat facing polar bears these days, and most of us have seen video or photographs of polar bears swimming long distances between ice floes. And when (about once a week) someone suggests placing big rafts in the ocean to facilitate polar bear survival, it comes as no big surprise.
But while the intention is good, floating platforms won't help polar bears--for many reasons.
First off, rafts wouldn't give polar bears a way to hunt seals, the main challenge they face in a warming Arctic. And while polar bears depend on sea ice as a hunting platform, they also rely on the sea ice for breeding and sometimes denning.
The sheer scale of the open water is also a factor; last summer's ice melt was equal to the size of Canada and Texas combined! So even if we added rafts to the water, bears would be unlikely to find them given the immensity of the area.
Just as important--and perhaps more so--is the critical role sea ice plays in the arctic food chain. According to Dr. Cecilia Bitz, a sea ice expert at the University of Washington, sea ice doesn't actually freeze solid at temperatures typical of the
Arctic. Instead, sea salt trapped inside makes it porous. The pores house algae and other microorganisms that form the first link in the arctic food chain--one that begins with these small life forms, and continues up to fish, seals, and finally polar bears.
Already, sea ice is melting sooner and forming later. A study published in Science found sea ice in the Arctic Ocean thinned and shrank to a record low in September 2012. The thinner ice allows more sunlight to get through and feed the algae that grow on the underside of the ice. As the ice melts, algae sink to the ocean floor and are eaten by brittle stars and sea cucumbers instead of by fish closer to the ocean's surface. Surface life, such as ringed seals, depend on the algae-eating fish that are now going hungry. And polar bears need seals to survive.
"At present there is sea ice covering a portion of the Arctic Ocean all year, although Hudson Bay has historically been ice-free in summer," says Bitz. "We project there will be little sea ice anywhere during summers before the end of this century. There is large uncertainty in exactly when the Arctic Ocean will be ice-free, but there is a good chance it will occur by mid-century if humans continue to emit greenhouse gases unabated."
If floating platforms aren't the answer to saving polar bears, what is? Research shows that saving sea ice by addressing climate change is the key. Plastic rafts would never be able to duplicate the complexity of that system.
But a promising shift to a sustainable society is underway in sectors including  transportation, energy usage, and food production. To help motivate action, we've launched our Save Our Sea Ice campaign, featuring a series of energy-saving challenges that change personal habits and inspire community leadership.
In the end, plastic rafts won't save polar bears. Instead, roll-up-your-sleeves actions and government change, miles from the fragile arctic ecosystem, are what it will take to preserve polar bears and life as we know it on Earth.
Please join us on World Oceans Day this Saturday, June 8th by honoring
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