- Written by Mark Pointing
- BBC News climate correspondent
Saving the ice – a daring experiment or a dangerous diversion?
Parka-wearing scientists watch water pour over the frozen sea above the sea ice off Canada’s northern coast.
What is their purpose? To slow global warming.
As sea ice disappears, the dark ocean surface can absorb more solar energy, accelerating warming. So researchers want to thicken it to prevent it from melting.
Welcome to the exotic side of geoengineering – the deliberate intervention in Earth’s climate system to counteract the damage we have done to the planet.
But more experimental measures go a step further and aim to reduce the energy the Earth absorbs.
Many scientists are strongly opposed, warning that such efforts risk distracting from important steps in reducing carbon emissions and causing more harm than good.
But a few proponents argue that their approach could give the planet a helping hand while humanity cleans up its act.
The ultimate goal of the Arctic experiment is to thicken sea ice enough to slow or reverse the melting already seen, said Dr Sean Fitzgerald, whose team at the University of Cambridge Center for Climate Remediation is supporting the project. says.
Will it work, or is it, as one scientist puts it, “very crazy”?
“The truth is, we don’t know enough about this to know whether this is a good or bad idea,” admits Dr. Fitzgerald.
“It’s quite cold,” the researchers say.Wind chills in Cambridge Bay, where temperatures can feel as low as -45 degrees
Researchers have endured harsh conditions in Cambridge Bay, a small Canadian village located in the Arctic Circle.
“It’s quite cold,” Andrea Cecolini of Real Ice, the British company leading the trip, told me over a speckled Zoom connection from inside a fluttering white tent.
“With strong winds, the temperature is about -30 degrees, but when you add the wind chill coefficient, the temperature becomes -45 degrees.”
They drill holes in the sea ice that forms naturally in winter, pumping about 1,000 liters of seawater to the surface every minute.
When exposed to the cold winter air, this seawater freezes rapidly, thickening the surface ice. Water also compacts snow. Fresh snow acts as an excellent insulating layer, making it easier for ice to form on the lower surfaces that touch the ocean.
“The idea is that the thicker the ice, the more [at the end of winter]They can survive longer when we enter the melting season,” explains Cecolini.
A pump is used to fill the surface of the sea ice with seawater and freeze the seawater.
When I spoke to them toward the end of the trip, they had already seen the ice thicken by tens of centimeters across their small study area. The ice will be monitored by local residents over the next few months.
But it’s still too early to tell whether their approach can actually make a difference in the rapid decline of 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 was not involved in the project.
One problem is that salty ice can melt faster in the summer.
In addition, there is the huge logistical challenge of scaling up the project to a meaningful level. By some estimates, about 10 million wind pumps could be needed to thicken just one-tenth of the sea ice in the Arctic.
“The fact that this could be done on such a large scale for the entire Arctic Ocean is, in my opinion, absolutely insane,” said Julian Straub, professor of polar observation and modeling at University College London. he says.
More experimental geoengineering proposals include generating additional wave spray to make clouds more reflective, or mimicking volcanic eruptions to reflect more of the sun’s energy back into space. Masu.
Many scientists, including the United Nations Climate and Meteorological Organization, have warned that such an approach could pose serious risks, including disrupting global weather patterns. Many researchers would like to see them banned completely.
“Geoengineering techniques involve great uncertainty and pose new risks to 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 system. Pumping seawater onto sea ice on a large scale could change ocean chemistry and threaten our fragile web of life.”
And there are more fundamental and broader concerns with this kind of project.
“The real danger is that it’s a distraction and that people with vested interests use it as an excuse to keep burning fossil fuels,” Professor Siegert warns.
“Frankly, this is outrageous and needs to be stopped. The way to solve this crisis is decarbonization. It’s our best and only way forward.”
Arctic researchers are keenly aware of these concerns. They stress that they are simply testing the technology and have no intention of releasing it more widely until the risks are better known.
“We’re not here touting this as a solution to Arctic climate change,” Dr. Fitzgerald stresses.
“We’re saying it’s a possibility.” [part of it]But we have to find out more before society can decide whether it’s a wise thing to do. ”
They agree that geoengineering is not a silver bullet to combat climate change, and that deep cuts in fossil fuel and carbon emissions are paramount to avoiding the worst consequences of warming.
But even with swift action, they say, the world still faces a difficult future.
The Arctic Ocean could become virtually ice-free by late summer at least once by 2050, and possibly sooner. As the graph below shows, it has already experienced a sharp decline since the 1980s.
“We need other solutions,” argues Jacob Pantling, a PhD student and researcher at the Climate Restoration Center who braves frigid winds in Cambridge Bay.
“We have to reduce emissions, but even if we do it as quickly as possible, the Arctic will still melt.”
