Cambridge, UK July 20, 2025
A monumental chapter in Earth’s climate history is unfolding at the British Antarctic Survey (BAS) in Cambridge, where scientists have received what is believed to be the oldest ice core ever recovered-possibly over 1.5 million years old.
Drilled from Little Dome C in East Antarctica, this 2.8-kilometre-long transparent cylinder of compressed polar ice holds within it the atmospheric secrets of a vastly different Earth. Encased in this ancient ice are air bubbles and dust particles that offer an unbroken record of atmospheric carbon dioxide, methane, temperature variations, and other key climate indicators dating back well beyond the previously established 800,000-year climate record.
“This is not just ice. It’s the atmosphere of ancient Earth, frozen in time,” says Dr. Robert Mulvaney, senior scientist at BAS and a lead researcher in the EU-funded Beyond EPICA - Oldest Ice project. “It offers the potential to radically deepen our understanding of how our planet’s climate has evolved-and how it might behave in the future.”
Unlocking the Mid-Pleistocene Mystery
The ice core is especially critical in studying the Mid-Pleistocene Transition, a period nearly one million years ago when Earth's glacial cycles mysteriously shifted from 41,000-year to 100,000-year intervals. Understanding this shift could provide crucial context for current global warming patterns and tipping points.
Researchers plan to use a cutting-edge laser-based sublimation method (deepSLice) to extract and measure trapped gases from the deepest and most compressed layers, preserving fragile atmospheric signals without destroying the sample.
Global Collaboration for a Global Challenge
The ice was transported in ultra-cold containers and is now being stored at -23°C at BAS’s secure freezer facility. From here, core segments will be distributed across specialized laboratories in Germany, Italy, Switzerland, and other EU nations under strict protocols. The Beyond EPICA team includes over a dozen institutions from ten countries, reflecting the global significance of this work.
“This is a once-in-a-generation opportunity,” said project coordinator Carlo Barbante. “We are looking backward to move forward-because solving the climate crisis begins with understanding it.”
A Message for the Present
As nations confront accelerating climate change, from rising sea levels to intensified heatwaves and ecological collapse, this ice core could offer essential clues about how Earth’s systems responded to past greenhouse gas levels. Importantly, it may provide a scientific baseline to measure humanity’s impact on the planet today.
For environmental scientists, educators, and policymakers, this marks a transformative milestone-where ancient ice might just shape the future of modern climate action.
