Latest news with #CíanSherwin
Scientific American
20-05-2025
- Science
- Scientific American
Inside the Bold Geoengineering Work to Refreeze the Arctic's Disappearing Ice
This story was produced in partnership with the Pulitzer Center's Ocean Reporting Network. A haze of ice crystals in the air created a halo around the low sun as three snowmobiles thundered onto the sea ice on a February morning in far northern Canada. Wisps of snow blew across the white expanse. It was –26 degrees Celsius as we left Cambridge Bay, an Inuit village in a vast archipelago of treeless islands and ice-choked channels. This temperature was relatively warm—six degrees C above average. The winter had been the mildest in 75 years. The sea ice covering the Arctic Ocean was at its smallest extent on record. Scientists predict that within the next 15 years this ice cap will disappear in summer for the first time in millennia, accelerating global warming. The U.K. company Real Ice, whose heavily bundled team was bouncing around on the other two snowmobiles ahead of mine, hopes to prevent that outcome with an effort that has been called extremely ambitious, insane or even dangerous. At a spot seven kilometers from the village, Real Ice co-founder Cían Sherwin, an Irishman with a red beanie and scraggy goatee, hopped off his snowmobile and started drilling with a long electric auger. A gob of water and frozen shavings sloshed up and out of the hole as he punctured the underside of the ice more than a meter below. Inuit guide David Kavanna widened the opening with a spearlike ice saw, then placed a wood box around it. Sherwin lowered an aluminum pump, which looked like a large coffee urn attached to a curved rubber hose, through the hole. He plugged a cable into a battery pack. After a few seconds water began pouring out of the hose, spilling onto the ice in an ethereal shade of blue. As it congeals, 'the water acts almost like lava,' Sherwin said. 'The ice formation starts almost instantly.' On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. Thin, broad sheets of ice expand from the ice cap's edges in winter, when it's dark and cold, and melt away in summer, when the sun shines 24 hours a day. The ice acts like a giant mirror, reflecting up to 90 percent of the sun's radiation back toward space. Ocean water, in contrast, absorbs 90 percent of sunlight. The ice cap's core of so-called multiyear ice, which persists year-round, has shrunk by about 40 percent in four decades, kicking off a vicious cycle: as more ice melts, more ocean water is exposed, and that water warms further, melting even more ice. If the ice starts disappearing entirely in summer, global temperatures could rise an extra 0.19 degree C by 2050. Real Ice is trying to thicken seasonal ice so it lasts longer into the warm months, keeping the planet cool. Sherwin hopes pumping could someday refreeze a million square kilometers of both seasonal and multiyear ice—an area the size of Texas and New Mexico combined and about a fifth of what's now left in summer—to stop the ice cap's death spiral. All it would take, Real Ice says, is half a million ice-making robots. Polar geoengineering on such an enormous scale could help slow warming until the world finally weans itself off coal, oil and natural gas. Many scientists think it will never work. The researchers at Real Ice argue we no longer have any option but to try; studies suggest that even slashing fossil-fuel use may not save summertime sea ice. 'It's sad that it's ended up that way, but we've got to do something about it,' Sherwin said to me out on the frozen plain. 'Emissions reduction is just not enough anymore.' Cambridge Bay, which British explorers named for a 19th-century Duke of Cambridge, is a town of 1,800 mostly Inuit inhabitants located across from the Canadian mainland on Victoria Island, one of the world's largest islands. When I landed at the one-room airport on a twin-engine turboprop, I was greeted by a stuffed musk ox and a placard about the 1845 British naval expedition of John Franklin. Cambridge Bay lies along the Northwest Passage, an icy sea route between Europe and Asia sought by explorers for 400 years. Franklin's two ships, Erebus and Terror, were trapped in the polar sea ice that surges down toward Cambridge Bay in winter, buckling into ridges up to 10 meters high. All 129 men onboard died of cold, starvation or disease. These days cruise ships coast through the passage every year, often visiting grave sites of Franklin expedition members. The Inuit call Cambridge Bay Ikaluktutiak, meaning 'good fishing place.' For millennia their nomadic ancestors came here to fish Arctic char, a silvery-orange cousin of the brook trout. Inuit started living here full-time in the 1940s and 1950s, when the U.S. military hired them to help build a navigation tower and a radar station to detect Soviet bombers coming over the pole. The cold war also led to the idea of controlling the Arctic environment. The U.S.S.R. discussed destroying sea ice with coal dust or explosions and detonated three nuclear devices to try to excavate an Arctic canal. In the U.S., physicist Edward Teller's Project Plowshare nearly got approval to gouge out a harbor in Alaska with atomic bombs. Geoengineering today is intended to cool Earth to fend off climate change. Some scientists and entrepreneurs are focused on dispersing sulfate particles in the stratosphere to block sunlight, which could lessen heating but also disrupt global weather patterns such as the South Asian monsoon. Mexico recently announced a ban on this solar geoengineering after Silicon Valley start-up Make Sunsets launched two balloons full of sulfur dioxide there. The city of Alameda, Calif., halted an experiment to spray sea-salt particles skyward to make clouds more reflective. Field trials targeting the Arctic, the Antarctic and the 'third pole' of colossal glaciers in the Himalayas have stirred up less controversy, perhaps because unintended consequences would be confined largely to those distant places. In Iceland and India, Silicon Valley nonprofit Bright Ice Initiative has scattered tiny glass beads on glaciers to try to reflect more sunlight and slow the melting. Chinese agencies have blown chemical smoke into clouds with rockets, planes, drones and chimneys to provoke snowfall over glaciers on the Tibetan plateau. Researchers in Scandinavia are developing giant curtains that could be anchored to the seabed to block warm ocean water from melting the undersides of ice shelves in Antarctica. Billions of dollars would be needed to affect the climate. The idea for thickening ice came from outer space. At a 2012 conference a fractious forum about global warming soured Arizona State University astrophysicist Steve Desch's hopes for quick climate action. Desch, who studies icy bodies such as Pluto's moon Charon, wondered whether we could buy time by making ice in the Arctic. The problem is that sea ice freezes from below. Once the first layer forms, it insulates the seawater from the air, which can be 50 degrees C colder. The thicker the ice gets, the slower it grows. In 2016 Desch published a paper proposing that wind-powered pumps could thicken sea ice by pulling up water from below and spraying it across the top. Around that time, students at Bangor University in Wales were inspired by a documentary on the Arctic to construct a 're-icing machine,' an ungainly spindle of hoses that twirled like a lawn sprinkler. One of those students was Sherwin. Encouraged by Desch's paper, he and London entrepreneur Simon Woods founded Real Ice in 2022 to see whether sea-ice thickening could scale up. They eventually recruited Desch and several sea-ice scientists as advisers. The company put its first water onto ice in Nome, Alaska, in January 2023, ditching the sprinkler for a commercial pump. They moved to the Canadian High Arctic Research Station in Cambridge Bay the next year to do more. 'It's not exactly the same as a natural process, but it's as close as you can get,' Desch says. After the team drilled the first hole that February morning and started the pump, we snowmobiled to a destination pinpointed by GPS several hundred meters away. Again the group drilled and inserted a pump, and water began whooshing out. In all, we installed four pumps in four places. As water pooled, the edges crept outward, soaking into the pockmarked snow, which was up to 25 centimeters (10 inches) thick and crusty like hardened white frosting. Within hours the pool would coagulate into electric-blue slush, like a gas station Slurpee. After a lunch of fruit bars and potato chips around a tiny gas heater in the team's rescue tent, we went to a site the crew had pumped a day earlier. Under a dusting of snow lay flat gray ice. With a drill bit almost as tall as himself, one of the volunteers bored a hole and dropped in a measuring tape with fold-out brass arms at its end. The ice was 152 centimeters thick; almost 30 centimeters of ice had been added, compared with untouched sites they measured. The ice would thicken further in coming weeks. Because snow is a better insulator than ice—this quality is why igloos work so well—flooding and freezing the snow could allow more cold to penetrate to the ice's underside, creating more ice. After Real Ice thickened 4,100 square meters of ice here in winter 2023–2024, the crew came back in May 2024 to find a significant increase. Across the area they had pumped, ice thickness was 1.9 meters, compared with 1.44 meters in other places. 'Ice growth from below—that's the really efficient part,' Woods told me as he drilled a measuring hole at another refrozen site. But snow is also a better mirror than ice, which could complicate the picture. Sea ice covered by snow reflects 90 percent of solar radiation, whereas bare sea ice reflects 50 to 70 percent. Real Ice would need snow to accumulate in spring to replenish the snow it flooded in winter, or the process could increase melting. That's just one way flooding snow could backfire. As seawater freezes, the salt in it is ejected from the ice crystals, leading ever saltier pockets of brine to form on the surface. Salt lowers the freezing point of ice, whether on winter roads or the sea. If pumping seawater leaves more salt on the surface in summertime, it could end up accelerating the disappearance of the ice. So far this doesn't seem to be happening. On another morning Woods put a hollow red barrel on the drill and bored into the ice at a refrozen site to extract an ice core about as long and thick as his arm. He held it up to the pale sun, which illuminated hairline channels where the salty fluid had eaten its way through the ice. 'This natural process helps the brine to migrate back into the ocean,' he said. It's still not clear how ice thickening will affect sea life, starting with the microscopic algae that grow on the underside of the ice. They're eaten by zooplankton, which are eaten by fish, which are eaten by mammals. On a different morning I snowmobiled with University of Alaska Fairbanks marine biologist Brendan Kelly to a low ridge formed by two enormous plates of ice pushing together. A polar science adviser in President Barack Obama's administration, Kelly has studied seals and polar bears for more than four decades. In that time he's also watched fossil-fuel emissions march steadily upward. So despite his discomfort with geoengineering, he agreed to advise Real Ice. In the hazy light, the monochrome landscape seemed devoid of life. But as we crunched on foot along the snow caking the ridge, Kelly stopped to point out an Arctic fox footprint. Farther on he found a urine stain, then desiccated green scat, then a small pit. 'Seal, probably,' Kelly said. In spring, ringed seals claw holes through snowdrifts. They hide their fuzzy white pups in these lairs while they dive for fish and crustaceans. Foxes and polar bears dig around to try to find the pups. Kelly scooped at the firm snow, tiny icicles swaying from his white mustache, but couldn't find a lair. Polar bears also depend on snow. They excavate dens in larger drifts to warm their cubs, which are born the size of a guinea pig. Most Arctic snow tends to fall in late autumn. It's unknown whether enough new snow would build up after wintertime ice thickening for bears and seals to make dens in spring. Of course, polar bears and seals are already expected to decline as their sea-ice habitat melts away. Is Real Ice doing more harm than good by pumping seawater into this environment, melting the snow? 'We don't know that,' Kelly said. 'But we need to know it.' Across two months last winter, Real Ice pumped water through almost 200 holes. Drills and snowmobiles broke, team members got frostnip, and Arctic foxes chewed through long, thin thermistor cables used to measure temperature in the snow and ice. The researchers thickened 250,000 square meters of sea ice. The ice cap is losing 300,000 times that area every year. The key to scaling up is to 'bring the engineering underwater,' Sherwin told me later. The Sant'Anna School of Advanced Studies in Pisa, Italy, is developing an underwater drone two meters long that will bore through ice from below with a heated pipe and start pumping water up through it. In renderings, it looks like a folding pocketknife with a pipe instead of a blade. Real Ice hopes to test a prototype this year, says co-CEO Andrea Ceccolini, an Italian computer scientist and investor who joined the company in 2022. The plan is to thicken 100 square kilometers of sea ice in winter 2027–2028 to demonstrate the technique to governments and investors. The approach verges on the fantastic. A swarm of 50 drones would melt holes in minutes and pump water as their infrared cameras monitored the progress. Technicians on a floating or onshore hub would swap out the drones' batteries, plugging the old ones into chargers powered by wind turbines or by green hydrogen or ammonia brought in by ship. Tapping into electricity from Canada's Nunavut region would contribute to climate change because most of it is generated from diesel fuel. The ultimate goal of thickening one million square kilometers of sea ice would take an estimated 500,000 drones, which would consume two terawatt-hours of electricity and require 20,000 people to service them, according to rough math Ceccolini has done. The cost would be $10 billion annually. The drones would vastly exceed the 3,800 Argo robot sensors circulating in oceans worldwide, and drone experts say a revolution in battery technology would be needed. How much global warming could be countered through sea-ice preservation depends on numerous variables affecting sunlight and melt dynamics. Preserving a million square kilometers of sea ice for one additional summer month would cool Earth as much as removing 930 million metric tons of carbon dioxide from the atmosphere over 20 years, Real Ice estimates. For these results, $10 billion is actually cheap, Ceccolini says, and the cooling would be immediate. Capturing that much CO 2 from the air with existing machines would currently cost at least $465 billion. For perspective, humanity emits 910 million tons of CO 2 every eight days, with no end in sight. Thickening sea ice is a Band-Aid 'while you cure the patient—the planet—properly,' Ceccolini says. Every day in Cambridge Bay, after three or four hours of flooding, the team used an ice ax to hack each pump out of its hole. Fat white frost flowers formed on top of the solidifying surface. The speed of the freeze was striking—but so was the immensity of the frozen plain stretching to the horizon. It was hard to envision hundreds of thousands of drones popping through the ice day after day, all winter long, for decades. The only highway in Cambridge Bay is the sea ice. In winter and spring, Inuit residents snowmobile hundreds of kilometers over it to go ice fishing and hunt musk ox and seals, local hunter Brandon Langan told me in his living room, a black musk ox hide hanging behind him. He works part-time for Real Ice flying airborne drones to monitor the thickened ice's reflectivity. When the ice recedes in summer, the Inuit fish the Arctic char that run into the bay from lakes and streams. When ice returns in fall, they hunt the caribou that cross it to the mainland. Two out of every three meals are fish or game. 'Sea ice, to us, it's life,' Langan said. 'It helps us get our food. It gives us our clothing.' Now hunters who used to start moving on the ice in October have to delay until December. A few have even fallen through. In spring, the ice cracks and melts sooner. Ice loss has diminished the local caribou herd by 90 percent; the animals go hungry waiting to cross, and when bottled up for too long on the shore, they're easier prey for wolves. Hundreds of caribou have drowned after breaking through the ice. One hunter who had previously been a guide for Real Ice told me at the cultural center in the high school library that he hopes ice thickening could rejuvenate game populations. Inuit insights are vital. Throughout history scientists and explorers often ignored Indigenous knowledge of the Arctic. The last time anyone saw the Franklin expedition was when Inuit hunters encountered starving sailors dragging a lifeboat across the ice in Washington Bay, clad in wool rather than furs. Franklin was dead, and the remaining explorers traded the Inuit beads for seal meat—they apparently didn't know how to hunt seal themselves. Later, native people found mutilated bodies farther south, indicating the explorers had resorted to cannibalism. Charles Dickens dismissed these reports, which were later confirmed, as 'the wild tales of a herd of savages' and suggested the Inuit had slain Franklin's men. This colonial mindset would persist as the Arctic came under government control. Canada and Alaska took Indigenous children, including some from Cambridge Bay, away to be reeducated in abusive residential schools, where thousands died. A week after I met with Langan I talked with Inuit Circumpolar Council international chairwoman Sara Olsvig, who has spoken out against testing the seabed-curtain idea in her native Greenland. She says governments need to start regulating geoengineering, and researchers need to seek the free, prior and informed consent of local communities. When somebody claims, ''We need your piece of land in the name of a greater good,' that's exactly what happened when we were colonized,' Olsvig says. Real Ice obtained permits from Nunavut's Inuit government, as well as the Cambridge Bay hunters-and-trappers organization. Ceccolini says the operation will shut down if ice thickening proves ineffective or damaging. Although the company may patent its drone technology, its articles of association prohibit it from distributing profits. But it would consider founding a new company with Indigenous part-ownership if it decided to scale up, Ceccolini says. Local elders are hesitant. They gather at the cultural center on weekdays to sew fur boots and mittens and speak the local language. During a break for black tea and candied Arctic char, I asked three of them about the sea-ice thickening. They would be concerned about the drones if Real Ice conducted its 100-square-kilometer demonstration, a key step to scaling up, in the strait near Cambridge Bay rather than farther north. 'If they start doing that under the water, we're going to get no more fish, no more seal, no more nothing,' said Annie Atighioyak, who was born in an igloo on the sea ice in 1940. As global fossil-fuel emissions keep rising, attitudes about geoengineering are starting to change. Two weeks before I arrived in Cambridge Bay I went to an annual Arctic science conference at the Oceanographic Institute of Monaco. Frederik Paulsen, a Swedish pharmaceutical billionaire in a tailored suit and rimless glasses, took the podium. Though not a scientist, Paulsen was the first person to reach all eight poles—the geographic, geomagnetic, magnetic and least accessible poles of each hemisphere—and was onboard one of the two submersibles that planted a Russian flag on the North Pole seabed in 2007. In 2023, while flying over Greenland in an ultralight aircraft, Paulsen was startled to notice that the once brilliant ice sheet was turning darker as less fresh snow fell. He said he decided only 'more drastic solutions' could avoid catastrophic climate impacts, given our failure to rein in fossil fuels. It's not enough to just study climate, he scolded the scientists. 'Now is the time to act.' The University of the Arctic, a network of educational institutions that Paulsen chairs, has rated the feasibility of 61 polar interventions, from spraying glaciers with ski-resort snow guns to cables that stop icebergs from drifting south. At the conference, John Moore, a University of Lapland glaciologist, presented the seabed-curtain idea. Also there was Fonger Ypma of Arctic Reflections, a Dutch sea-ice-thickening company that has done field trials in Newfoundland and Svalbard. Last year he went to Cambridge Bay to learn from Real Ice, but he hopes to deploy large movable pumping platforms rather than drones. The surge of interest has created a schism in polar science. In October 2024 a preprint paper by 42 top glaciologists condemned ice thickening and other polar geoengineering techniques as dangerous and unfeasible. Seabed curtains could disrupt nutrient flows to CO 2 -consuming phytoplankton. Spreading tiny glass spheres across mountain glaciers could decrease the reflectivity of ice covered in fresh snow. But the overarching concern is that geoengineering fixes are 'making decarbonization a lot less attractive,' according to Heidi Sevestre, one of the paper's authors, who visited an Arctic Reflections trial last year. What they are offering 'doesn't attack the cause of the issue, the fossil fuels,' she says. At the Monaco conference, Kim Holmén, a Norwegian Polar Institute climate scientist who has spent more than three decades on Svalbard, the fastest-warming place on Earth, argued that trying to undo the harms of our technology with even more technology was folly. 'I make mistakes every day, you make mistakes every day, and if we create a system where it must work every day, it will fail,' he said. Critics say it would be more effective to put geoengineering funds toward cutting emissions. The amount being spent on Arctic geoengineering is small but growing. Arctic Reflections has raised $1.1 million and Moore $2 million. Real Ice's directors have committed $5 million to its ice-thickening project, only a fraction of the cost for a 100-square-kilometer demonstration. It's hard to imagine state agencies allocating $10 billion a year for sea-ice thickening, especially with China, Russia and reportedly the U.S. looking to develop Arctic shipping routes; for them, less ice is better. Brazil's Amazon Fund for rainforest conservation, which Real Ice has held up as a possible funding model, has collected only $780 million from governments. Private investors might mean fewer political obstacles. In March, Paulsen, who's offering a €100,000 prize for projects 'reversing Arctic change,' convened a dinner in Geneva to introduce geoengineering researchers—including a Real Ice adviser—to two dozen potential donors. He wants to hold similar 'adopt-a-billionaire' gatherings in the U.S. He also claims he's discussed geoengineering with officials from the Trump administration, which withdrew the U.S. from the Paris climate agreement. The administration didn't respond to a request for comment. Real Ice and Arctic Reflections would like to eventually sell 'cooling credits,' a strategy used by Make Sunsets. Individuals and companies that want to compensate for their CO 2 emissions pay that start-up to launch balloons full of sunlight-blocking sulfur dioxide. Carbon credits have paid for the planting of trees to remove tens of millions of tons of CO 2 from the atmosphere. But the credit arrangements also have been criticized as a 'license to pollute' to avoid fossil-fuel reductions. Some of the biggest buyers are tech firms such as Microsoft, whose emissions are swelling as the company builds AI data centers. Kelly, the former White House adviser, is indeed worried that geoengineering could be 'hijacked' by oil or tech companies as an excuse to continue business as usual. But he's more concerned about the gigantic geoengineering experiment he says we're already conducting by emitting tens of billions of tons of greenhouse gases every year. Ice companies just have to be willing to shut down their technology if it starts harming nature or undermining climate goals, he told me as we drank coffee at the research station in Cambridge Bay. They have to be willing to turn back, unlike Franklin and other overconfident explorers who came here to discover the Northwest Passage. 'We all have to keep asking ourselves and checking ourselves and one another: Have we slid into hubris?' Kelly said. 'The alternative is to think [we humans] know what's best, that we can get through the passage.'
Scientific American
16-05-2025
- Science
- Scientific American
Polar Geoengineering Experiments Bet Big on Freezing Arctic Ice
Refreezing the melting sea ice in the Arctic is more complicated than you would think. The U.K. is funding geoengineering experiments like this one to curb the effects of climate change. By , Alec Luhn, Fonda Mwangi, Alex Sugiura & Jeffery DelViscio This story was produced in partnership with the Pulitzer Center's Ocean Reporting Network. Rachel Feltman: For Scientific American 's Science Quickly, I'm Rachel Feltman. You don't have to pay much attention to the news to know that climate change is causing Arctic sea ice to melt—and to understand that this is a huge problem. Ice reflects sunlight, which helps keep cold places cold. Warmer weather means less ice, but less ice means more heat from the sun, which means it gets warmer, which means there's less ice—and the sea level keeps rising and rising. On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. It would be great if we could cut this problem off at the source by dropping our greenhouse gas emissions, but we're not exactly making great progress on that front. In the meantime what if we could just make more ice? It might sound silly, but some folks in the polar geoengineering space are making a very serious attempt to do just that. To get the inside scoop I'm handing the reins over to Pulitzer Center ocean reporting fellow Alec Luhn. He's the author of a feature on the subject in Scientific American 's June issue, and today he's going to take us along on a trip to the Arctic. [CLIP: Snowmobile engine starting.] Alec Luhn: I'm snowmobiling out onto the sea ice from the Inuit village of Cambridge Bay in Canada's Arctic Archipelago. It's –26 degrees Celsius. That's –15 degrees in Fahrenheit. The blasting wind makes it feel far colder. My goggles are freezing over, and my thumb is getting numb on the throttle. But this is actually warm for Cambridge Bay in February. It's been the warmest winter in 75 years, and the temperature at the North Pole even briefly went above freezing. In front of me a local Inuit guide is towing a sled full of team members from the U.K. company Real Ice to a point about seven kilometers [roughly 4.3 miles] from town. Scientists say as early as the 2030s the Arctic ice cap could start melting away completely in the summertime, raising temperatures around the globe. Real Ice hopes to stop that by artificially freezing more sea ice. It's one of several geoengineering projects trying to save the world's glaciers, ice sheets and sea ice. Some scientists think it's ridiculous or even dangerous, but Real Ice co-founder Cían Sherwin says we no longer have any option but to try. Cían Sherwin: So right now we're about to start drilling the—that 10-inch [25.4-centimeter] auger hole for the pump. [CLIP: Cían Sherwin drills into the sea ice.] Luhn: Cían was part of a student group at Bangor University in Wales that built a 'reicing machine' after they saw a TV documentary about the melting Arctic. In 2022 he co-founded Real Ice to try it on a larger scale. The ice outside Cambridge Bay is more than a meter [approximately 3.3 feet] thick. Cían drills a hole in it with a long battery-powered auger. If you've ever been ice fishing, you've seen this kind of tool. It looks kind of like a jackhammer, only with a giant rotating screw rather than a chisel at the end. Inuit guide David Kavanna widens the edges of the hole with an ice saw, and the team puts a wooden box around it. Cían lowers an industrial pump with a long hose through the hole. He plugs a cable into a battery pack, and seawater starts pouring out of the hose, creating a brilliant blue pool on the sea ice. Sherwin: Where that flow rate isn't as strong, the ice—or the water acts almost like lava, becoming thicker in viscosity, and ice formation starts to begin almost instantly. Luhn: Sea ice freezes from below, where there's water that's just under zero degrees C [32 degrees F]. But once the first layer of ice forms it partially insulates that water from the freezing air above, which can be as cold as –50 degrees C [–58 degrees F]. So the thicker the ice gets, the slower it grows. Real Ice is trying to bring the water up to the cold air by pumping it on top of the sea ice. After about three hours the team comes back to take the pump out. The pool of water has congealed into an electric blue slush, like a gas station Slurpee. Sherwin: So by the time we return here now, tomorrow morning, this will already be frozen. Luhn (tape): New sea ice? Sherwin: New sea ice—or a new layer on top of the sea ice. Luhn: Releasing small particles to block sunlight is probably the most common geoengineering idea. It's also highly controversial because it could affect weather, like rainfall. Mexico banned solar geoengineering after an American firm released balloons full of sulfur dioxide there. A city in California recently halted an experiment spraying sea-salt particles into the air. In May the U.K. allocated about $75 million to geoengineering research, becoming one of the first countries to fund outdoor experiments in this field. One experiment will launch balloons to test mineral dust that could someday be released into the atmosphere to block sunlight. Another two will develop nozzles to spray sea-salt particles, including potentially over Australia's Great Barrier Reef. But the largest grant in the British program, about $13 million, went to a research group that includes Real Ice. It also includes the Dutch company Arctic Reflections, which has been testing giant pumping platforms to thicken sea ice in Svalbard [Norway] and Newfoundland, Canada. Polar geoengineering trials have been moving forward in other places, too. A U.S. nonprofit has been scattering tiny white clay granules to reflect more sunlight away from glaciers in Iceland and the Himalayas. And a Scandinavian project has been testing materials for huge underwater curtains to try and stop warm water from reaching the underside of Antarctic glaciers and melting and collapsing them. If it works, polar geoengineering like sea-ice thickening could affect the entire Earth. Arctic sea ice is like a big mirror, reflecting up to 90 percent of the sun's radiation back into space when it's covered in snow. But ocean water absorbs 90 percent of sunlight. The more ice melts, the more ocean water warms. That heats up the planet—and melts even more ice. The thick sea ice that lasts year round has shrunk about 40 percent in the last four decades. If it starts melting away completely in the summertime, global temperatures could rise an extra 0.19 degrees C [roughly 0.34 degrees F] by 2050. Last winter real ice thickened about 250,000 square meters [almost 2.7 million square feet] of sea ice. In the winter of 2027–28 the company plans to thicken 100 square kilometers [about 38.6 square miles] as a demonstration. If that works, the team hopes it could scale up to eventually keep Arctic sea ice from disappearing in the summer. Sherwin: Targeting an area roughly a million square kilometers [about 386,100 square miles]across the entire Arctic region could be enough to help prevent the loss of sea ice. Luhn: On the one hand that's small: it's one fifth of how much ice is currently left in the summertime. On the other hand it's enormous: the size of Texas and New Mexico combined. Real Ice says it could be possible. All they'd need is half a million underwater drones. Real Ice has been working with the Sant'Anna School of Advanced Studies in Italy to develop a two-meter-long [about 5.6-feet-long] automated drone. In a computer rendering the drone has a pipe that folds out like a pocket knife. The pipe would be heated so it could melt through the sea ice from below and then pump water on top of it. Real Ice hopes to test a prototype by the end of the year. The idea is that something like 20,000 technicians will be working on onshore and offshore platforms, swapping out batteries so the 500,000 drones can keep thickening sea ice. The old batteries would have to be recharged with wind power or green ammonia or hydrogen. That would have to be brought in by ship, since the Nunavut region's grid is all diesel. Andrea Ceccolini: Half a million drones might seem like a large figure. Luhn: That's Andrea Ceccolini, a wealthy tech investor who is co-CEO of Real Ice. Ceccolini: We produce, globally, over 90 million cars every year. We also produce more than 40 million e-bikes. Luhn: But only about a few dozen underwater drones have ever been deployed under polar ice, such as the U.K.'s $1.3 million Boaty McBoatface. The closest equivalent to what Real Ice is proposing would probably be the 3,800 Argo floats deployed around the ocean. And these floats only need enough power to measure temperature and salinity as they drift with the ocean currents. Craig Lee is a University of Washington oceanographer who helped develop low-power Seaglider drones that operate under polar ice. I spoke with him on video call after I got back from Cambridge Bay. He says it wouldn't be feasible to swap out thousands and thousands of batteries every day in one of the harshest environments on Earth. Craig Lee: You'd need a revolution in how the vehicles are powered. That's not gonna happen on any battery that we currently use today. Luhn: He says keeping that many remote drones in good repair would also be impractical. Right now the only way to deliver equipment to Arctic communities like Cambridge Bay is on a ship that comes through once a summer when the ice melts or by propeller plane. The village lies in the heart of the Northwest Passage, the infamous sea route between Europe and Asia that took sailors 400 years to successfully navigate. The first thing I saw when I landed at the one-room airport was a stuffed musk ox, which looks like a bison with shaggy black fur, and a plaque about the doomed 1845 expedition of John Franklin. One of Franklin's two captains was confident they could get through the passage in less than a year. Instead their ships became trapped for a year and a half in the polar ice that surges down the channel toward Cambridge Bay. The men abandoned the vessels, and eventually all 129 of them died of cold, starvation or disease. Some resorted to cannibalism. With sea-ice thickening Real Ice is also entering uncharted territory. I wondered if abandoned ice making drones would someday join Franklin's ships at the bottom of the passage. The first big question is salt. When seawater freezes, the salt in it is ejected, and pockets of brine form on the ice's surface. Salt lowers the melting point of ice, which is why trucks spread salt on the roads in winter. If pumping seawater means that more salt remains on the ice during the summer, it could accelerate the melt and make the ice thickening largely pointless. So far that doesn't appear to be happening. Out on the ice Simon Woods, a London software entrepreneur who co-founded Real Ice with Cían, attaches a long red barrel to a drill and bores into the ice. He pulls out an ice core as long and thick as his arm and holds it up to the low sun. Simon Woods: Can you see them? Luhn (tape): Yeah, those kinda little—just little lines in the ice. Woods: Yeah, those are brine channels. Luhn: The brine appears to be eating through the ice, returning the salt to the ocean. Snow is another wild card. The water pumped by Real Ice floods the crusty snow that covers the sea ice, freezing it solid. Have you ever wondered how Inuit people were able to live in igloos? That's because snow is actually a really good insulator. Simon drills through the ice and drops in a measuring tape with foldout brass arms to measure its thickness. The team has added 20 to 30 centimeters [about 7.9 to 11.8 inches] of ice by pumping water and freezing the snow. But that's not the end of the story. Woods: But what we're hoping to see later in the season is that that exposing [of] the surface so that there's less, less snow cover means that it's less insulated, improves the conductivity of the whole stack so we get ice growth from below. That's the really efficient part of the process. Luhn: At the same time snow is a better mirror than ice. Bare ice reflects about half as much solar radiation back into space as ice covered in snow. Real Ice needs the snow to accumulate again in the spring or the company's process could increase the melt rate. The animals living on the ice also need that snow to come back. Brendan Kelly, a marine biologist at the University of Alaska Fairbanks, used to be a polar science adviser to the Obama administration. Now he's advising Real Ice on possible consequences its plans could have for the ecosystem. With Brendan I walk along a low ridge where two massive pieces of ice are pushing together. We see a patch of yellow snow—you know what that means. A few meters further is a dry green turd. Then we come to a small pit dug in the snow. These are traces of an Arctic fox, the fluffy white cousin of the red fox most of us know. [CLIP: Brendan Kelly's and Alec Luhn's footsteps crunch in the snow.] Brendan Kelly: The fox has come in, marked and dug. He thought something was there. Luhn: That something might've been a ringed seal. These animals dig layers under snow drifts to protect their fuzzy white pups from predators. The mother seal leaves her pup in the lair while she dives for fish and crustaceans. Arctic foxes and polar bears often try to root out the pups for dinner. Brendan is trying to understand how flooding the snow for sea ice thickening could impact seal reproduction. Kelly: Birthing won't happen until April. So it's just a question: If you came into an area and you flooded it, say, in February, would enough snow accumulate again by birthing time for them to maintain lairs? Luhn: Foxes and polar bears dig snow dens, too, so they could also be affected if there isn't enough snow buildup. But the alternative doesn't look great either, given that the sea ice they live on is melting. The Arctic is warming about four times faster than the planet as a whole. Kelly: We've done some modeling, my colleagues and myself, and project that about 70 percent of the suitable habitat in terms of snow cover in the Arctic will be gone by the end of the century, so massive loss of habitat. Luhn: The Inuit residents of Cambridge Bay also rely on the sea ice for their survival. There's no highway here, only the ice. People depend on it to go hunting and fishing. Only about one third of the food they eat is store-bought. When the ice recedes in the summer the Inuit fish the arctic char that run into the bay from lakes and streams. When the ice returns in the fall they hunt the caribou that cross it on their annual migration. They also hunt ringed seals and musk ox. Some Inuit residents think sea-ice thickening could improve hunting. Others aren't so sure. On weekday afternoons community members gather at the heritage center in the high school library to sew fur boots and mittens and speak the local language. I came by to drink tea and ask about sea-ice thickening. Luhn (tape): What's the word for sea ice in Inuktitut? Eva Komak: Just hiku, hiku. Community members: Hiku. Luhn: The sea ice has been forming later in the fall, which means locals have to wait longer to start hunting their food. A few have even fallen through the ice on their snowmobiles. Hundreds of caribou have fallen through, too. Ice loss has slashed the local herd by 90 percent. That's a big deal for Cambridge Bay. David Hanak: The sea ice, it's really important because we have to get to our destination to get our food sources out, out on the land. Luhn: That's David Hanak, a hunter who has occasionally worked as a guide for Real Ice. We were eating pieces of candied arctic char, which was the color of salmon and tasted sweet and smoky at the same time. He hopes that sea-ice thickening could someday help rejuvenate hunting and fishing around Cambridge Bay. Hanak: But I would say, yeah, it's a pretty—a good idea to take out the water from the ocean and put it right on top the ice to make it thicker and thicker. Luhn: But some of the elders here have their doubts. Annie Atighioyak was born in 1940 in an igloo on the sea ice. Speaking through an interpreter she raised questions about the potential consequences. [CLIP: Annie Atighioyak speaks in Inuinnaqtun.] Komak (translating for Atighioyak): They have mixed feelings, too. We all do. Luhn: Real Ice isn't sure where it will try to do its 100-square-kilometer demonstration. But if it's in the strait near Cambridge Bay, Annie says she'd be concerned about the underwater drones disturbing wildlife. [CLIP: Atighioyak speaks in Inuinnaqtun.] Interpreter (translating for Atighioyak): Doing that under the water, we're gonna get no more fish, no more seal, no more. Luhn: Inuit activists have accused other geoengineering projects of colonial thinking. Iñupiaq people in Alaska said a field trial that scattered tiny silica beads on a lake there failed to obtain their free, prior and informed consent. Sarah Olsvig, the international chair of the Inuit Circumpolar Council, has spoken out against a proposed seabed curtain test in her native Greenland. Sarah Olsvig: I would say, when somebody approaches the Arctic and our homelands as Indigenous peoples and say, 'We need your piece of land in the name of a greater good,' that's exactly what happened when we were colonized. Luhn: She says geoengineering, which exists in a legal gray area, needs to be better regulated. Real Ice obtained permits from the regional Inuit government and the Cambridge Bay hunters and trappers organization. The company says it would do an environmental and social impact assessment to make sure the larger demonstration it plans wouldn't cause other significant harm. Let's say Real Ice continues to scale up and achieve its dream of thickening one million square kilometers of sea ice. If that ice could be preserved for one additional summer month, the company says it would cool the planet as much as removing 930 million metric tons of carbon dioxide from the atmosphere for 20 years. It sounds like a lot, but humanity emits about that much CO 2 every eight days. In other words, sea-ice thickening won't be worth much if we don't start reducing emissions. Andrea, the Real Ice Co-CEO, calls it a Band-Aid that would give humans time to actually heal the planet. The next question is: Who's gonna pay for it? Real Ice's directors have committed $5 million to research, plus part of the $13 million from the U.K. government. But thickening one million square kilometers of ice would cost an estimated $10 billion annually. Real Ice hopes to eventually get more funding from governments, like the Amazon Fund to save the rainforest has—although the Amazon fund has only raised about $780 million. So the company also wants to sell cooling credits, a kind of carbon offset. Companies that want to reach net-zero targets would pay Real Ice to do a certain amount of planetary cooling on their behalf. Critics say all this money would be better spent on decarbonization efforts like investing in solar and wind energy. In a preprint journal article 42 top glaciologists argued that sea-ice thickening and other polar geoengineering techniques are infeasible and dangerous. The scientists say these approaches could hurt ecosystems as well as our sense of urgency to tackle climate change. Brendan, the marine biologist, is worried geoengineering could become an excuse to continue business as usual. Kelly: Even if we got the technology and the science right, will we get the, the social contract, the social—the governance correct? That's really hard to imagine—you know, that we won't get hijacked. Luhn: But he's even more worried about the geoengineering he says we're already doing by pumping billions of tons of CO 2 into the atmosphere. Kelly: In, you know, an optimistic scenario a lot of things have to line up for thickening sea ice to be a net positive for the planet, right? All the issues of scale and, you know, feasibility and engineering and impacts on biota and timeliness. But we're somewhat desperate as a planet, I'd say. Luhn: Even if we stop emitting CO 2 tomorrow, some research suggests it may be too late to save summertime sea ice. That's why Real Ice says that at the very least we need to see if sea-ice thickening works, if it might actually be able to refreeze the Arctic. Feltman: That's all for today's Friday Fascination. We'll be back on Monday with our science news roundup. Don't forget to fill out our listener survey if you haven't already done so! You can find it at Science Quickly is produced by me, Rachel Feltman, along with Fonda Mwangi, Kelso Harper, Naeem Amarsy and Jeff DelViscio. This episode was reported and co-hosted by Alec Luhn and edited by Alex Sugiura. Shayna Posses and Aaron Shattuck fact-check our show. Our theme music was composed by Dominic Smith. Subscribe to Scientific American for more up-to-date and in-depth science news. For Scientific American, this is Rachel Feltman. Have a great weekend!
