The first scientific results from GreenDrill, a pioneering drilling initiative led by researchers from the University at Buffalo and Columbia University, reveal that the Prudhoe Dome ice cap in northwest Greenland completely melted around 7,000 years ago—far more recently than scientists had previously believed. Published in Nature Geoscience, the study provides striking new evidence that portions of the Greenland Ice Sheet are highly sensitive even to modest natural warming, raising concerns about their vulnerability under today’s human-driven climate change.
GreenDrill is a first-of-its-kind project designed to retrieve frozen bedrock and sediment from beneath the Greenland Ice Sheet—materials that hold direct records of when ice retreated in the past. Remarkably, scientists possess more physical samples from the Moon than from beneath Greenland’s ice, despite the latter being crucial for understanding long-term ice stability and future sea-level rise. Chemical and physical signatures preserved in buried sediment can reveal when those materials were last exposed to sunlight, providing a precise timeline of ice-sheet collapse.
The study focused on core samples drilled 1,669 feet below the surface at the summit of Prudhoe Dome during a demanding field campaign in 2023. Using luminescence dating, researchers measured the glow emitted by mineral grains when exposed to light—an indicator of how long sediment has been buried. Results showed that the Prudhoe Dome sediment last saw daylight between 6,000 and 8,200 years ago, meaning the ice cap must have fully melted earlier, during the early Holocene.
Crucially, this period of ice loss occurred during a time of relative climate stability, when global temperatures were only about 3 to 5 degrees Celsius warmer than today. That finding underscores the sensitivity of this region of the ice sheet. Climate projections suggest that comparable warming could be reached locally by 2100, implying that similar ice retreat could happen again—this time driven by anthropogenic greenhouse gas emissions. As lead scientists emphasize, the past provides a direct analogue for Greenland’s potential future.
The implications for sea-level rise are significant. Studying vulnerable margins like Prudhoe Dome allows scientists to identify where ice loss is likely to begin and which coastal communities may face the earliest risks. By directly sampling sub-ice geology, GreenDrill offers something numerical models alone cannot: physical proof linking specific levels of warming to actual ice loss.
The project also builds on historical precedents, including Cold War–era drilling at Camp Century, which unexpectedly recovered sediment later used to show Greenland was much smaller hundreds of thousands of years ago. However, GreenDrill is the first effort to deliberately choose drilling locations specifically to recover subglacial material for climate reconstruction.
Despite logistical challenges—ranging from extreme weather to fractures in the ice that nearly halted drilling—the team successfully completed the cores through ingenuity and collaboration. Researchers describe the experience as both stressful and humbling, given the realization that landscapes now buried under kilometers of ice were recently ice-free and may be again.
Looking ahead, the team sees this study as only the beginning. Additional cores from thinner ice near the dome’s edge may reveal even more about Greenland’s most fragile zones, while plant remnants could illuminate ancient Arctic ecosystems. Ultimately, GreenDrill establishes a powerful new approach for anchoring climate projections in direct geological evidence, strengthening confidence in predictions of future ice loss and sea-level rise.
https://phys.org/news/2026-01-greenland-prudhoe-dome-ice-cap.html