Preliminary 2026 analyses show the Little Dome C core preserves an unbroken climate record reaching at least 1.2 million years, carrying direct samples of ancient atmosphere across the Mid-Pleistocene Transition.
A 2,800-metre borehole drilled to bedrock in January 2025 recovered bubbles containing measurable CO2, methane and other gases, extending the previous Dome C atmospheric archive by about 400,000 years.
The project aims to explain why glacial cycles shifted from roughly 41,000-year spacing to about 100,000 years around 1 million years ago, a change older cores could not directly track with greenhouse-gas data.
Researchers caution the deepest 210 metres are heavily deformed and may be out of chronological order, so dating relies on ice-flow models, chemical correlations and krypton-81 tests as labs assemble the full chronology.
Beyond EPICA’s value is continuity: unlike isolated ancient ice fragments or indirect marine-sediment estimates, one continuous core lets scientists compare temperature, dust and trapped air through the climate-system reorganization itself.
If the deepest Antarctic ice is heavily deformed, how can scientists truly guarantee the accuracy of this 1.2-million-year-old climate timeline?
What triggered the mysterious plunge in Earth's CO2 levels 950,000 years ago, and could this ancient ice reveal our climate's future?
Beyond EPICA’s 1.2-Million-Year Ice Core: Engineering Triumph and the Search for Earth’s Oldest Climate Secrets
Overview
The Beyond EPICA–Oldest Ice project achieved a major milestone by drilling a 1.7-mile-long ice core in Antarctica and delivering it to European labs in 2026. Scientists are now analyzing this 1.2-million-year-old ice to directly measure ancient greenhouse gases and temperatures. These unique records will help solve the mystery of why Earth's climate cycles shifted from 41,000 to 100,000 years during the Mid-Pleistocene Transition. By understanding how changes in ice sheets and greenhouse gases drove this shift, researchers can refine climate models and better predict how modern ice sheets and sea levels will respond to human-caused emissions.