Steve Desch is a professor of astrophysics at the School of Earth & Space Exploration at Arizona State University who's come up with a novel plan to rescue the rapidly melting Arctic. He and a team of university colleagues want to replenish the region's shrinking sea ice by building 10 million wind-powered pumps over the Arctic ice cap. In winter these would be used to pump water to the surface of the ice, where it would freeze, thickening the cap.
According to Desch, this is an urgent climate-change issue facing the planet. In a research article in the journal Earth's Future called "Arctic Ice Management," he described it in alarming terms.
"As the Earth's climate has changed, Arctic sea ice extent has decreased drastically," he wrote. "It is likely that the late-summer Arctic will be ice-free as soon as the 2030s."
Already, the region's warming trend is breaking records. Last November, when sea ice should have begun thickening and spreading over the Arctic as winter set in, the region warmed up. Temperatures should have plummeted to -25 degrees C but reached several degrees above freezing instead. This warming is unprecedented, according to researchers. Even in January the Arctic sea ice was the lowest in 38 years since satellites began surveying the region, according to the National Snow and Ice Data Center.
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This is a situation that threatens the planet's sustainable future. The loss of the Arctic's summer sea ice cover disrupts life in the region, endangering many of its species. It would also trigger further warming of the planet by removing ice that reflects solar radiation back into space, disrupt weather patterns across the Northern Hemisphere and melt permafrost, thus releasing more carbon gases into the atmosphere.
He said that it's likely already too late to reverse the situation by decreasing temperatures and carbon dioxide levels, and simply telling people not to use fossil fuels isn't enough. This being the case, his article proposes restoring the region's sea ice artificially, by using wind power to pump water to the surface during the winter, where it will freeze more rapidly.
That may sound like a lot, but Desch said the time has come to start thinking big.
"Every year, there is more ice melting in the summer and less freezing in the winter," he told CNBC. "We're losing 300 cubic kilometers per year on average. The Arctic is losing ice the size of an ice cube that's 4 miles on each side (that's 64 cubic miles annually)."
Desch proposes the use of wind power to pump water from below the sea ice to the surface, in order to accelerate the rate of freezing. The technology that he proposes to do the job is utterly simple.
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"Imagine a buoy bigger than a minivan, with a wind turbine on top," he said. "One device could pump up enough water to increase the thickness of the ice by one meter over an area one-tenth of a square kilometer."
While the buoy that Desch proposes is a simple bit of technology, his plan would require a lot of them to achieve the results he feels are appropriate. That's where the $500 billion price tag comes in.
"We would need 10 million devices, at $50,000 per device," he said.
He added that the entire $500 billion sum would not have to be used all at once. His plan could be spread out over as much as a full decade to lessen the pain.
Still, this would be an enormous task, and his estimate accurately reflects the logistics involved in getting something this big up and running.
"This is sort of Manhattan Project or Iraq War in scope, so it's not impossible if we make it a priority," he said. "If you want to reverse that situation, you want to do something big. It's not impossible. It's big, but it's not impossible."
Desch's proposal is not the only one that's out there that addresses the rapidly melting Arctic ice. According to The Guardian, an alternative proposal involves artificially whitening the Arctic by scattering light-colored aerosol particles over it, which would reflect solar radiation back into space. Desch, however, isn't looking to introduce anything new into the Arctic ecosystem.
"One advantage of our approach over other geoengineering ideas is it's purely mechanical," he said. "We're not introducing any new chemicals into the environment. We're proposing accelerating a process that naturally should be occurring, and trying to restore the ice to the point where it was 20 years ago."
So who might foot the bill for this effort? Desch doesn't believe it will be a single philanthropist or angel investor who will write a $500 billion check and get the ball rolling. In fact, he believes that an undertaking of this size should be the responsibility of numerous parties.
"We don't think any one person would unilaterally do this, or should," he said. "A project this size needs a government to get involved, and the restoration of sea ice is important at a local scale as well. Coastal erosion is accelerating and permafrost is dying, so I can imagine starting on a smaller scale there."
— By Daniel Bukszpan, special to CNBC.com