Geoengineering is now essential to saving the Arctic’s ice

The first explorers known to have reached the North Pole spent weeks dragging their sleds across the rough pack ice. Now, people can travel most of the way there from the comfort of a cruise ship, their passage eased by the catastrophic melting of ice caused by climate change.

The Arctic is shedding ice at a rate of 12 per cent per decade and is set to be ice-free in the summer by the 2030s – regardless of how fast we cut emissions from now on. Meanwhile, in Antarctica, the vast Thwaites glacier is cracking under the pressure of global warming, and Antarctic sea ice has been tracking at record lows in 2024 for the second year running.

We must cut emissions, and fast, but that alone won’t be enough to stop the runaway melt in the Arctic. To buy us time and to buttress this delicate habitat from a warming world, geoengineering is probably our only hope.

One solution comes from start-up Real Ice, which plans to use seawater to thicken the Arctic’s ice. It is controversial. Geoengineering of this sort, opponents argue, risks distracting humanity from the gargantuan task of cutting emissions.

Yet there are good reasons to push ahead. Alongside the spectacular wildlife and rich cultural heritage there, the polar regions do the world a huge favour. Their white caps reflect solar radiation back into space, helping to keep Earth’s climate cool. The loss of Arctic sea ice also triggers a whole host of other feedbacks that would amplify climate change and play havoc with weather systems around the world.

Of all our geoengineering options, refreezing the poles is perhaps the most benign. There are, of course, risks. Thorough impact assessments will be vital to minimise any harmful effects on wildlife, local communities or wider Earth systems. But without action, the ice will disappear, destabilising the global climate.

Cuts to greenhouse gas emissions should have started decades ago. The delay has left us with no time to be squeamish about geoengineering.