Re-freezing the North Pole? A giant sea curtain? High-tech efforts to save the Arctic are doomed, report finds

Moonshot proposals to save the planet’s ice sheets, including giant underwater sea curtains and refreezing Arctic ice, are gaining popularity as the planet heats up. But none of the most high-profile ideas are viable — worse, they may cause irreparable harm, according to a new study published Tuesday.

The melting of the vast polar ice sheets has become a byword for climate change; these giant frozen landscapes hold enough water to cause catastrophic sea level rise and are experiencing alarming changes as temperatures increase.

Ideas to artificially cool the Arctic and Antarctic, known as “polar geoengineering,” are gaining profile as a result. Academics have launched research projects, start-ups are proliferating and investors are piling in.

Geoengineering advocates say the urgency of the climate crisis makes it vital to research these potential fixes. The authors of the report, published in the journal Frontiers in Science, say they are a dangerous distraction.

“These ideas are often well-intentioned, but they’re flawed,” said Martin Siegert, a glaciologist at the University of Exeter and a study author. He and a team of international scientists analyzed five of the most well-publicized ideas:

• Pumping seawater onto ice to artificially thicken it or scattering glass beads to make sea ice more reflective;

• anchoring giant curtains to the seabed to prevent warm water melting ice shelves;

• drilling down to pump water from beneath glaciers to slow ice sheet flow; and

• adding nutrients like iron to polar oceans to stimulate carbon-sucking plankton.

The scientists assessed each proposal for its effectiveness, feasibility, risks, costs, governance issues and scalability. None of the five ideas “pass scrutiny” and all “would be environmentally dangerous,” the report concluded.

The Arctic and Antarctic are among the planet’s harshest environments, and these ideas — many of which go beyond anything humans have tried before — do not consider these challenges, Siegert said.

None of the methods has been robustly tested at scale, with no real-world experiments at all for sea curtains, said the report, which found each of the five ideas risked “intrinsic environmental damage.”

Sea curtains could disrupt the habitats of marine animals including seals and whales; drilling holes to remove water from beneath glaciers could contaminate a pristine environment; and spraying particles into the stratosphere could change global climate patterns, according to the report.

The proposal to scatter tiny glass beads onto the surface of the ocean to stop it absorbing the sun’s heat was one of the more concerning, the report authors said.

Research run by the Arctic Ice Project looking at the impact of glass beads in the ocean was wound down earlier this year after ecotoxicological tests “revealed potential risks to the Arctic food chain,” according to a statement on the organization’s website. It also blamed a “broad scepticism toward geoengineering.”

The price tag on these interventions would also be eye-watering, with each estimated to cost at least $10 billion to set up and maintain, according to the report. Sea curtains were among the most expensive, projected to cost $80 billion over a decade for a 50-mile curtain.

Even if the projects could overcome significant hurdles, none could be deployed on sufficient scale and quickly enough to meet the urgency of the climate crisis, the report concluded. “They become a distraction away from what we know we need to do… and that is to reduce our emissions,” Siegert said.

But some scientists, while endorsing the need to drastically reduce planet-heating pollution, warned against cutting off research into polar geoengineering.

“Unfortunately, we are faced with severe environmental damage without geoengineering,” said Shaun Fitzgerald, director of the Centre for Climate Repair at the University of Cambridge, who is involved in climate engineering projects. “Rather than saying we should not look further into geoengineering, we should instead be seeking a debate about the relative risks,” he added.

Pete Irvine, a research assistant professor in geophysical sciences at the University of Chicago, called the report “a one-sided analysis of polar geoengineering proposals that stresses only the side-effects, downsides and potential for misuse.”

He said solar geoengineering, for example, wasn’t a substitute for emissions cuts, “but these interventions might make a significant contribution to the health of our planet.”

Some warned the world was now so far off track on climate action that it was vital to keep studying polar geoengineering. It “is essential and urgent, particularly in Arctic regions where the impacts are most apparent,” said Hugh Hunt, deputy director of the Centre for Climate Repair at the University of Cambridge.

However, other scientists said the study offered a thorough and much needed review of the risks.

“Fundamentally, the paper shows clearly and farsightedly that these polar geoengineering interventions are a dangerous distraction from reducing carbon emissions and do not pose a realistic or cost-effective solution,” said Bethan Davies, a chair in glaciology at Newcastle University.

Tina van de Flierdt, head of the department of Earth Science and Engineering at Imperial College London, said: “As somebody who has conducted challenging fieldwork in the Antarctic, I want to emphasize that all suggested methods are either scientifically flawed, unproven, dangerous or logistically unfeasible.”

Siegert says he understands the appeal of these silver bullet projects, but, he warned, “the polar regions are fragile, pristine systems and once they’re disturbed and ruined, they are ruined forever.”

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