The Arctic is our planet’s reflective shield, bouncing back plenty of incoming solar radiation into space. Without it, our planet would warm at an unfathomably fast pace, which is why scientists are deeply concerned that much of the sea ice there seems to be disappearing. In fact, global sea ice is at its lowest ever extent, and you don’t get any prizes for guessing why.

There are really only two solutions to this. Either we cut down on fossil fuels and ramp up our use of clean and renewable energy, or we come up with a mad-cap geoengineering scheme to save the world. A team from Arizona State University, thinking that rapid global warming is now inexorable, have plumped for the latter choice.

“This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean,” the authors write in the journal Earth’s Future. “It is unlikely that CO₂ levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative.”

So, in order to bring back the ice to the Arctic, all you need is 10 million wind-powered pumps. During winter, these would force colder waters to the surface, allowing them to freeze and adding at least an extra meter (3.3 feet) or so to the sea ice there.

As noted in the Observer, this would cost around, oh, say $500 billion.

Don’t get us wrong – it’s definitely worth doing something to save the Arctic for a whole host of reasons, including our own continued survival as a species. Geoengineering plans, though, are fraught with difficulty.

Although this particular scheme is scientifically sound, it's pretty expensive, and it’s unclear what other secondary effects such an extensive change to the water flow around “10% of the Arctic” will have.

It certainly seems less risky than previous climate change mitigation plans have sounded, particularly ones that revolve around firing reflective aerosols into the sky to stop so much sunlight getting through.

The scientists here are right to point out that an ice-free Arctic does seem increasingly likely by the 2030s, though. Even with the Paris agreement in full force, it’s not likely in its present state to stop a fairly dangerous degree of global warming from happening, especially in the Arctic, which warms twice as fast as the rest of the planet.

If anything, this ambitious scheme highlights just how much more work needs to be done on cutting our carbon emissions. You know the planet’s in trouble when geoengineering plans as grand as this one are being considered as genuine possibilities by the world’s best scientists.