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- By Mark Poynting
- BBC News climate reporter
Saving the ice: a bold experiment or a dangerous distraction?
Perched on sea ice off Canada’s northern coast, parka-clad scientists watch as salt water gushes over the frozen ocean.
Your goal? To stop global warming.
As sea ice disappears, the dark surface of the ocean can absorb more energy from the Sun, accelerating warming. That’s why researchers want to thicken it to prevent it from melting.
Welcome to the crazier side of geoengineering: deliberately intervening in the Earth’s climate system to try to counteract the damage we have caused it.
But more experimental measures aim to go one step further, seeking to reduce the energy absorbed by the Earth.
Many scientists are strongly opposed, warning that such attempts distract from the critical step of reducing carbon emissions and risk doing more harm than good.
But a small number of advocates say their approaches could help the planet as humanity cleans itself up.
The ultimate goal of the Arctic experiment is to thicken the sea ice enough to slow or even reverse the melting already observed, says Dr Shaun Fitzgerald, whose team at the University of Cambridge’s Center for Climate Repair is behind the project. .
Will it work or is it, as one scientist said, “pretty crazy”?
“We don’t really know enough to determine whether it’s a good or bad idea,” Dr. Fitzgerald admits.
“It’s pretty cold,” the researchers say. Wind chill in Cambridge Bay can feel like -45°C
Researchers have been braving bitter conditions in Cambridge Bay, a small Canadian village in the Arctic Circle.
“It’s pretty cold,” Andrea Ceccolini of Real Ice, a British company leading the trip, tells me over a spotty Zoom connection from inside a billowing white tent.
“It’s about -30°C with a strong wind, bringing the temperature to -45C with wind chill factor.”
They are drilling a hole in the sea ice that forms naturally in winter and pumping around 1,000 liters of seawater per minute through the surface.
Exposed to cold winter air, this seawater freezes quickly, helping to thicken the surface ice. Water also compacts snow. As fresh snow acts as a good insulating layer, ice can now also form more easily on the bottom in contact with the ocean.
“The idea is that the thicker the ice is (at the end of winter), the longer it will survive when we enter the melting season,” explains Ceccolini.
A pump is used to flood the surface of the sea ice with seawater, which will then freeze.
Towards the end of their trip, they told me that they had already seen the ice thickening by a few tens of centimeters in their small study area. Locals will be keeping an eye on the ice in the coming months.
But it’s still too early to say whether their approach can really make a difference in the rapidly declining Arctic sea ice.
“The vast majority of polar scientists think this will never work,” warns Martin Siegert, an experienced glaciologist at the University of Exeter, who is not involved in the project.
One problem is that saltier ice can melt more quickly in summer.
And then there is the enormous logistical challenge of scaling up the project to a significant level: one estimate suggests that around 10 million wind pumps could be needed to thicken sea ice in just a tenth of the Arctic.
“In my opinion, it’s crazy that this can be done on a scale for the entire Arctic Ocean,” says Julienne Stroeve, professor of polar observation and modeling at University College London.
Some of the more experimental geoengineering suggestions include trying to make clouds more reflective by generating additional sea spray and mimicking volcanic eruptions to reflect more of the Sun’s energy back into space.
Several scientists – including UN climate and weather bodies – have warned that these approaches could pose serious risks, including disrupting global weather patterns. Many researchers want to ban them altogether.
“Geoengineering technologies carry enormous uncertainties and create new risks for ecosystems and people,” explains Lili Fuhr, director of the Fossil Economy Program at the Center for International Environmental Law.
“The Arctic is essential to sustaining our planetary systems: pumping seawater over sea ice on a large scale could change ocean chemistry and threaten the fragile web of life.”
And there is a more fundamental and widespread concern with these types of projects.
“The real danger is that it provides a distraction and people with vested interests will use it as an excuse to continue burning fossil fuels,” warns Professor Siegert.
“Frankly, it’s crazy and it needs to be stopped. The way to solve this crisis is to decarbonize – it’s our best and only way forward.”
Arctic researchers are well aware of these concerns. They stress that they are simply testing the technology and will not use it more widely until the risks are better understood.
“We are not here promoting this as the solution to climate change in the Arctic,” Dr. Fitzgerald stresses.
“We’re saying it could be (part of it), but we have to go and find out a lot more before society can decide whether it’s a sensible thing to do or not.”
They agree that geoengineering is not a magic bullet to address climate change, and that sharp cuts to fossil fuels and carbon emissions are most important to avoid the worst consequences of warming.
But they point out that even with quick action, the world still faces a difficult future.
The Arctic Ocean is likely to be effectively free of sea ice by the end of summer at least once in 2050, and possibly even sooner. As the chart below shows, it has already seen sharp declines since the 1980s.
“We need other solutions,” argues PhD student Jacob Pantling, a researcher at the Center for Climate Repair who braved the wind chills in Cambridge Bay.
“We have to reduce emissions, but even if we do it as quickly as possible, the Arctic is still going to melt.”