Wind turbines could be used to create more sea ice in the Arctic in a massive geoengineering scheme on the scale of the Manhattan Project, scientists have said.
The increasing loss of ice, which reflects much of the heat from the sun, and the release of currently frozen stores of potent greenhouse gas methane threaten to create runaway global warming that would affect the entire planet.
Experts believe the Arctic could be essentially free of sea ice for the first time in about 100,000 years within the next few decades. The famously impassable North West Passage is already open to shipping and fossil fuel companies are considering drilling in the region.
A team of scientists from Arizona State University has now suggested trying to counteract the loss of sea caused by rising temperatures in the Arctic, which has seen increases well above the global average. In Svalbard, winter temperatures have been up to 11C higher than the late 20th century.
The researchers estimated covering more than 10 per cent of the Arctic with the wind-powered pumps would cost about $500bn (£404bn) over 10 years.
However, writing in Earth’s Future, a journal of the American Geophysical Union, they said doing this “could more than reverse current trends of ice loss in the Arctic”.
They warned that even if humans stopped producing carbon dioxide emissions it would still be “too late to prevent loss of summer sea ice in the 2030s”.
“Restoring Arctic sea ice thus probably requires a local solution tailored to that part of the climate system,” the scientists wrote.
“Happily, though, any prevention of Arctic sea ice loss has the advantage of arresting the most powerful feedback in the climate system and making global climate change easier to deal with.”
The pumps could also potentially be used to increase the amount of sea ice cover to beyond historic levels.
“Could this approach be used to help the Arctic cool the Earth more effectively than it did in the 1980s and before?” the researchers wondered.
Fresh snow reflects up to 90 per cent of sunlight, while sea ice reflects up to 70 per cent. Open water, however, absorbs about 94 per cent of the energy from the sun.