Scientists uncover Greenland's ancient melting beneath 600 meters of ice

A research team led by Caleb Walcott-George has completed a daring expedition to Greenland's Prudhoe Dome, one of the island's largest ice caps. The scientists drilled through 600 meters of solid ice to extract ancient sediment samples—marking the first time such material has been recovered from beneath the ice sheet.

The expedition took place in spring 2023 under harsh Arctic conditions. Temperatures plunged to -56°C, and winds reached speeds of 110 km/h. Despite these challenges, the team successfully retrieved ice cores and sediment from beneath the 2,500-square-kilometre dome.

The site was chosen partly due to its Cold War history. Camp Century, a secret US military project, once operated nearby. But the real focus was scientific: the team sought clues about the ice sheet's past behaviour.

Analysis of the cores revealed a surprising discovery. The Prudhoe Dome had melted entirely around 7,100 years ago. This finding adds to concerns about Greenland's current ice loss, which has accelerated in recent decades.

Since 2000, glaciers in northern Greenland have thinned rapidly. Ice loss jumped from about 20 gigatonnes per year in the early 2000s to over 50 gigatonnes by the 2010s. Rising air temperatures—up to 3°C warmer—and warmer ocean currents have driven the retreat.

The expedition provides concrete evidence of past melting at Prudhoe Dome. With Greenland holding the planet's second-largest ice reservoir, the findings could help predict future ice loss. The team's work also highlights the growing urgency of studying Arctic climate change.