Spraying Seawater on Arctic Ice Could Slow Polar Melt, Researchers Say

Experiments to refreeze melted Arctic sea ice are offering new hope. The technique, called 're-freezing', involves pumping seawater onto the ice during winter, where it freezes and creates a buffer that survives the summer melt. In northern Canada, a team drilled through the ice at minus 40 degrees and pumped 50,000 tons of seawater onto it. The layer, initially 1.5 meters thick, gained an extra 50 centimeters across an area of 450 by 450 meters. While the surrounding ice melted, the test patch remained largely intact.

The approach mirrors the sand-suppletion method used to reinforce Dutch beaches and dunes. The company behind the project, Real Ice, estimates it would cost around $10 billion annually to halt the shrinkage of Arctic ice. Since 1979, 3 million square kilometers of polar ice have disappeared, and each year around 80,000 square kilometers is lost. The loss accelerates because ice reflects 70 percent of solar heat back into space, while open water reflects only 7 percent.

Critics caution that geo-engineering should not distract from cutting CO₂ emissions. There are also concerns about environmental impact, as the refrozen ice has a different composition, reflecting more sunlight than natural ice, which may affect local flora and fauna. Researchers say they are studying these effects alongside the refreezing work.