Every winter, Canadian researchers construct approximately 7,000 kilometers of ice roads. This innovative method involves pumping water onto the surface, where it freezes, thereby thickening the ice layer for large vehicles, analogous to what’s shown in the Ice Road Truckers television series.

Could we apply this technique to Arctic sea ice to prevent its rapid disappearance? This crucial question is being explored through geoengineering experiments conducted in Canada and Norway during 2024 and 2025. The implications are significant, as Arctic sea ice is projected to completely vanish during summer months by the 2030s. The loss of ice diminishes its capability to reflect sunlight, exposing the ocean’s surface, which absorbs more heat.

Both trials demonstrated that sea ice thickness increased, with Canadian scientists reporting a slower melting rate during summer, while Norwegian researchers asserted otherwise. Ongoing tests are crucial for confirming these findings.

“Yes, the ice is getting thicker, but how that affects its eventual disappearance remains an unresolved issue,” observes Christian Haas, who analyzed results from the Norwegian study at the Alfred Wegener Institute in Bremerhaven, Germany.

In April 2024, researchers from Dutch company Arctic Reflections drilled a hole through about a meter of ice in a lagoon in Svalbard, subsequently injecting seawater to create a significant puddle of slush that froze solid within three days, increasing the sea ice thickness from 90 centimeters to 1.16 meters. However, by June, cameras observed that the thickened ice began to deteriorate and ultimately melted away.

Between December 2024 and February 2025, British company Real Ice executed similar operations, flooding eight sites in the Northwest Passage, just south of Indigenous communities in Cambridge Bay, Canada. This experiment resulted in frozen sections extending to 250,000 square meters, effectively doubling the thickness of the ice.

By May 2025, average thickness at sites flooded in January and February reached 1.93 meters, compared to 1.62 meters at control sites.

The process of seawater freezing expels salt, making the ice more saline. While thicker ice is easier to form, Haas warns that this saline condition can ultimately accelerate melting, akin to salting roads in winter: “It’s not just about thickness; quality matters too,” he states.

Yet, brine might also facilitate melting water drainage, potentially mitigating ice loss. Andrea Cecolini, from Real Ice, indicated that melting in Canadian trial sites appeared slower than average, extending an additional 7 to 10 days beyond historical trends.

Both experiments indicated an increase in ice brightness with thickness. Satellite imagery from June highlighted the Real Ice test site as a prominent white patch amidst melting waters. “We were contributing to the effort against climate change,” Cecolini asserts.

Nevertheless, the Arctic Reflections study concluded that the cooling effects may not sufficiently counterbalance the warming introduced by pumps and vehicle emissions.

Years of research are essential to evaluate whether thickening Arctic sea ice could effectively support conservation efforts, as emphasized by Michelle Tsamados from University College London, who is modeling these dynamics with £9.9 million in funding from the UK government, which also sponsors Real Ice and Arctic Reflections.

“The local effects could be beneficial,” Tsamados mentions. “But what about larger scales? Can we achieve this over 10km or 100km?”

The implications for ice-dwelling organisms like algae, polar bears, and seals remain uncertain. However, if it proves viable, Real Ice anticipates deploying half a million underwater drones to refreeze up to 1 million square kilometers of sea ice.

Arctic Reflections is also evaluating areas, such as the Channel, where sea ice tends to migrate south and melt.

Last year, a collective of 42 scientists published an article contending that polar geoengineering, including sea ice thickening, may be impractical and could hinder emission reduction efforts.

“This technique might work on a small scale but isn’t a feasible large-scale solution,” argues Michael Meredith, formerly with the British Antarctic Survey and not involved in this research.