Greenland nuclear base site was ice-free 416,000 years ago, study reveals

Researchers examining sediment recovered from <b>Camp Century</b> in northwestern Greenland discovered that the Cold War military base site was completely ice-free roughly <b>416,000 years ago</b>. Built by the US Army Corps of Engineers in 1959, the subterranean base now sits beneath 1,387 metres of ice. Scientific analysis of biological markers within the sediment revealed that summer temperatures during Marine Isotope Stage 11 were about <b>4.7°C warmer</b> than modern conditions. The molecular traces also indicated increased atmospheric water vapour and local moisture sources supporting tundra and aquatic plant life. The findings offer critical insights into Greenland's sensitivity to prolonged warmth and sea-level rise risks. Researchers emphasize that limiting both the magnitude and duration of future summer warming is essential to preventing significant ice-sheet loss.