A team of scientists and engineers is conducting an unprecedented geoengineering experiment in the Arctic aimed at thickening and preserving sea ice amid rapid climate-driven melting. The project, led by the company Real Ice and funded by the UK government, seeks to determine whether artificially thickening sea ice can help slow the region’s devastating ice loss.

In November, the team drilled holes in Arctic sea ice near Cambridge Bay, an Inuit community in Canada’s high north, and pumped roughly 50,000 tonnes of ocean water onto the ice surface. This water froze quickly, increasing the ice thickness by approximately 50 centimeters (20 inches) atop an existing 1.5-meter base. The additional layer has shown early success in protecting the ice during the critical start of the melt season.

Andrea Ceccolini, a co-founder of Real Ice, described the visible contrast between the new bright white ice and surrounding melt ponds visible today. The experiment took place amid unseasonably warm temperatures in the bay, measuring over 5°C compared with an expected range of -6°C to 1°C, underscoring the urgency of addressing accelerating ice loss.

Arctic sea ice has declined by about 40% over the past 45 years, disrupted by global warming that reduces reflective ice cover and exposes darker ocean surfaces, which absorb more solar heat. This feedback loop heightens warming and speeds melt, with some projections suggesting the potential disappearance of summer sea ice within the next decade.

To monitor the experiment’s effects, the team has gathered detailed data on ice thickness, reflectivity, and salinity. Satellite imagery shows the treated area as a distinct white patch amid surrounding blue open water days into the melt season. Real Ice’s earlier trial last year thickened the ice by roughly 30 centimeters, and they anticipate the current augmentation could extend ice lifespan by 7 to 10 days.

An unexpected observation is that the artificially thickened ice appears more reflective than natural ice, potentially due to air bubbles trapped during rapid freezing, which increase opacity. Independent scientists from the University of Washington are conducting parallel measurements to validate these findings.

The local Inuit community, which relies heavily on sea ice for transportation, hunting, and fishing, has been engaged throughout the project. Kyle Weese, an Inuit guide working with Real Ice, noted changes in ice conditions experienced firsthand over the years, including thinner ice and delayed freeze-up. He expressed cautious optimism about the initiative, recognizing the importance of preserving ice for cultural and subsistence needs.

The broader question remains whether this approach can be scaled to address the vast areas of sea ice that have vanished, approximately 3 million square kilometers since 1979, with an additional 80,000 square kilometers lost annually. Real Ice is exploring autonomous, hydrogen-powered underwater drones capable of drilling holes and pumping water from beneath the ice to the surface. Trials of prototypes took place in Finland, and further development continues in Italy.

While the team estimates that halting the annual shrinkage of Arctic sea ice could cost around $10 billion over the longer term, the project faces scientific and ethical challenges. Many polar scientists caution against geoengineering, warning it could be environmentally risky, may distract from urgent emissions reductions, and could have unintended consequences.

Prof Shaun Fitzgerald, director of the Centre for Climate Repair at the University of Cambridge, emphasized that cutting greenhouse gas emissions remains essential but advocates for careful research into supplemental interventions. “Anything new has the potential for unintended consequences," he said, likening it to clinical trials that require rigorous assessment.

Real Ice founder Ceccolini acknowledged the complexities involved, framing their work as part of a broader investigation into practical climate strategies. “We are here to resolve the research questions: Is ice thickening effective, does it have side effects, and can it be scaled economically?” he said. “Then there are bigger questions, like: are governments, policymakers, and communities interested? Is society open to this type of solution?”