In the minutes it takes to read this article, nearly 12 million tons of ice will have melted away from Greenland’s ice sheet alone.In August, scientists made a startling discovery: Even if global warming serendipitously ceased to exist today, the melting process already underway is now irreversible. Sea ice in the polar regions is melting so fast that the Arctic may be ice-free by the 2030s, and Antarctica's glaciers are unstable and at risk of collapsing.
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Ice loss puts the planet at risk for a cascade of environmental issues. The thinning and loss of sea ice, for example, accelerates global warming. Glacial ice loss, on the other hand, acidifies the ocean, modifies weather patterns, and contributes to global rising sea levels, The latter leaves hundreds of millions vulnerable: coastal flooding, erosion, and compromising drinking water supplies, to name a few.“The melting we’ve been experiencing is not going to get better—it’s only going to get worse,” said Catherine Walker, a glaciologist at Woods Hole Oceanographic Institution in Massachusetts.While human-caused global warming has taken the world’s ice past the tipping point, some say the only solution must also come from humans in the form of massive intervention to reverse the warming processes already underway. Enter: Geoengineering.Geoengineering is an umbrella term for the controversial idea of intervening in the Earth’s natural systems using emerging technologies to counteract the climate crisis. The solutions vary tremendously in viability, side effects, infrastructure needs, and timeline. Where they do intersect is scale: the proposed solutions are as big and potentially disruptive as the processes they’re intended to halt.“We’re past the point of no return if we don’t do negative emissions or geoengineering,” said Peter Irvine, climate change lecturer at University College London. “But with these, we could stabilize things.”
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Glaciologists, however, have many concerns about the possible unintended side effects of these solutions. Will geoengineering do more environmental harm than good?“Geoengineering gives us a modicum of hope that we can find a technological fix, but I think we’re much more likely to end up with massive unintended consequences from any experiment we would try to do,” said Dr. Michele Koppes, a glaciologist at the University of British Columbia.
According to Professor Helen Amanda Fricker, a glaciologist at Scripps Polar Center at Scripps Institution of Oceanography, Earth’s systems are complex and there is so much unknown about polar regions that it is impossible to fully assess the environmental impacts of any geoengineering solution.“Why wouldn’t we just fix the root cause?” asks Fricker. “We know how to change things. We’re causing it in the first place.”Intertwined with engineering feasibility is the issue of scale. Antarctica, for example, is roughly the size of Mexico and the U.S. combined. Rolling out a solution on the glacial body would be a massive undertaking. “My gut reaction is we can’t even fathom how we would make a dent in these changes with any kind of geoengineering solution,” said Koppes.For geoengineers, however, too much is at stake to not consider alternate solutions.“To the best of our knowledge, the ice sheets are at severe danger,” said John Moore, a geoengineer and climate scientist at China's Beijing Normal University. “You have to put it in perspective: There are enormously bad things that will happen if we carry on just emitting greenhouse gases.”“We know how to change things. We’re causing it in the first place”
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What exactly would geoengineering solutions look like? Here are four leading concepts relating to melting polar ice.
Stratospheric Aerosol Injection
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Refreeze Sea Ice
Reflecting Sunlight With Silica Beads
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Can it work? The technology has been tested on contained pools of seawater in Utqiaġvik, Alaska, located north of the Arctic Circle. The scientists' preliminary findings are that silica bead-treated ice has higher reflectivity and thickness than untreated ice. The researchers propose strategically placing the beads for maximum impact using climate modeling.What’s the downside? The silica beads would break down in the ocean—the sea naturally has 2.8 million billion tons of silica—raising questions about environmental impact. Leslie Field, Arctic Ice Project founder and CTO, said the next step is to collaborate on an ecotoxicology study to confirm her team’s findings that the beads are harmless to the local ecosystem. “My mantra here is first do no harm,” said Field.Proposal: A team of international scientists suggests creating an underwater seabed curtain to block the warm water that is eroding the base of ice sheets. Inspired by kelp beds found in nature, the curtains—made of Teflon-coated glass fiber cloth, reinforced with hollow fiberglass pipes—would be anchored to the seabed. The concept evolved from a 2018 idea to prop melting glaciers using underwater sills.Cost: A curtain outside Antarctica’s Thwaites Glacier alone would cost $20 billion.Can it work? Bowie Keefer, adjunct at the University of British Columbia and mastermind behind the sea curtain idea, said the idea currently looks effective and feasible. That said, the idea has only undergone very preliminary modeling. Keefer isn’t recommending this should be built at this point, but that it should be further explored.What’s the downside? Cost and engineering in harsh environments. Keefer admits the landscape and cold temperatures would make building a sea curtain very difficult. But he still says it’s vital to assess it as a potential intervention to halt the underwater erosion of polar ice.