In January 2025, a drilling crew in East Antarctica accomplished a remarkable feat by accessing bedrock, around 2,800 meters below the surface, and extracted ice that has been undisturbed for over a million years. This astounding find took place at Little Dome C, a part of the Beyond EPICA – Oldest Ice initiative, which includes collaboration among ten European nations led by the Italian National Research Council. Key collaborators encompass Germany’s Alfred Wegener Institute, France’s CNRS, and the British Antarctic Survey. The initiative aimed to eclipse the previous ice age record held by the EPICA Dome C core, which dates back about 800,000 years. The new core achieves this, potentially reaching 1.2 million years according to early field evaluations.
The present age estimate of the ice derives from continuous-flow isotope assessments carried out on-site. These provide an initial but usable estimate of its age, while definitive dating will necessitate laboratory analysis in Europe. This thorough examination will utilize various methods, including ratios of trapped gases and geochemical indicators. Although reaching bedrock and obtaining a continuous ice column of this length is verified, the exact age remains an initial approximation.
Establishing the ice’s age is crucial since ice cores serve as historical archives, capturing atmospheric bubbles, dust, volcanic ash, and other indicators from the time the snow fell. A 1.2-million-year-old ice core would enable scientists to analyze the atmosphere during the Mid-Pleistocene Transition, a significant era when Earth’s glacial cycles changed from 41,000 years to around 100,000 years between ice ages. The reason for this shift continues to be a subject of inquiry in climate science. While current indications suggest a possible influence of atmospheric carbon dioxide levels, these are inferred from ocean sediment cores rather than direct atmospheric samples. An ice core from this era could facilitate direct measurements of greenhouse gases, yielding clearer understandings.
Beyond EPICA initiated site-selection surveys in 2016, employing radar technology to chart East Antarctica’s ice sheet. Little Dome C was chosen partly due to the perception that the ice was unaffected by deformation or basal melting, which poses challenges at other locations. Drilling began in the 2021-2022 Antarctic season, progressing incrementally each season until reaching bedrock in January 2025, resulting in an extensive core extending approximately 2,800 vertical meters of snow.
Following this, the collected ice will be transported back to consortium laboratories for thorough analysis. These investigations are anticipated to span several years as scientists utilize multiple independent dating methodologies. Should the 1.2-million-year estimate prove valid, it could offer an unmatched atmospheric perspective on the Mid-Pleistocene Transition. This may potentially alter or enhance our comprehension of why Earth’s ice ages shifted in pace and frequency. Ultimately, whether the ice supports prevailing theories or uncovers new facts remains to be determined.