Field experiments have shown that pumping seawater onto the snow atop Arctic sea ice helps thicken the ice, providing a viable method to maintain the ice cover through the summer.
A bold plan to pump seawater into the frozen Arctic Ocean may offer humanity a final chance to prevent the gradual disappearance of sea ice in the region. Field tests conducted this year in the Arctic waters off Canada aimed at thickening the sea ice by utilizing seawater from below have been successful, according to the British startup Real Ice, as reported by New Scientist on September 23.
Seawater is pumped onto the snow on the ice to thicken the ice. (Photo: Real Ice).
Arctic sea ice is rapidly shrinking due to climate change. Many scientists predict that this area will be ice-free in the summers of the 2030s, even with immediate and drastic reductions in emissions. Now, the only way to save summer sea ice in the region is to find ways to artificially thicken the ice.
Real Ice’s solution involves drilling through the ice to the ocean below and then pumping seawater onto the snow above the ice. The seawater will saturate the air pockets in the snow and freeze, turning the snow into ice. This method will increase the thermal conductivity of the ice shelf, meaning that cold air from the Arctic will spread and promote the formation of more ice beneath the ice shelf. “Our goal is to demonstrate that the ice thickening solution can be effective in maintaining and restoring Arctic sea ice,” said Andrea Ceccolini, a representative of Real Ice.
This method was first proposed by researcher Steven Desch at Arizona State University and colleagues in 2016. They estimated that deploying ice thickening across 10% of the Arctic area could reverse the recent decline in ice in the region.
In collaboration with the Climate Restoration Center at the University of Cambridge, Real Ice is conducting field tests in Cambridge Bay on Victoria Island, Canada, this year. The company reported that the tests have validated the concept. A pilot drill thickened the ice shelf by 50 cm compared to a control site from January to May. Results showed that the technique promoted natural ice thickening of 25 cm beneath the ice shelf, according to researcher Shaun Fitzgerald from the University of Cambridge. The experiment also demonstrated that saline water leftover after the seawater freezes drips back into the ocean rather than remaining in the upper frozen layer of the ice shelf, which could weaken the structure and lead to early melting.
When deployed at a sufficiently large scale, the technique could extend the lifespan of Arctic sea ice while people reduce emissions to combat climate change, according to Ceccolini. It also helps maintain the albedo effect, where intact ice reflects sunlight back into space, preventing the planet from continuing to warm.
This year’s experiment by Real Ice covered only a large area of ice the size of a football field. To create an effective impact, they will need to address thousands of square kilometers, requiring numerous pumps and drilling holes. To achieve this, Real Ice plans to develop an underwater drone capable of moving through the Arctic, drilling cores through the ice at strategic locations to pump seawater into the ice shelf. The company has partnered with the BioRobotics Institute at the Sant’Anna School of Advanced Studies in Pisa, Italy, to design the drone. Their goal is to have a prototype ready by 2025 and test it during the winter of 2026-2027 in the Arctic.
A single drone can handle 2 km2 of ice each season. Initial calculations suggest that 500,000 drones would be needed to create an additional 500 km3 of sea ice each winter over a total area of one million km2. Implementing this on such a scale would cost approximately $6 billion per year, funded by governments through the United Nations.
Real Ice will return to Cambridge Bay in November to conduct a large-scale experiment with 5 drilling holes spread over one km of sea ice. The company will confirm how much thicker the ice can be by early winter.
