Researchers Discover the Most Ancient Ice on Earth, Dating to 6 Million Years Ago
A revolutionary finding has been achieved by a group of U.S. researchers associated with the Center for Oldest Ice Exploration (COLDEX), who have discovered the planet’s most ancient directly dated ice and air. This ice, located in the Allan Hills area of East Antarctica, has been identified as being an astonishing 6 million years old, exceeding previous findings by more than 3 million years. As per a research article published in the Proceedings of the National Academy of Sciences, this finding provides crucial understanding into Earth’s geological history and ancient climatic conditions.
Lead researcher Sarah Shackleton from Princeton’s Woods Hole Oceanographic Institution referred to ice cores as “time machines” that permit scientists to investigate Earth’s history. Notably, the Allan Hills cores allow us to look back much further than was previously considered feasible. To determine the age of the ice samples, scientists examined the argon isotopes from air bubbles trapped in the ice, assessing radioactive decay for their dating. They also analyzed oxygen isotopes to confirm that the area underwent a cooling of approximately 22°F during the Pliocene period.
Grasping the levels of atmospheric greenhouse gases and ocean heat content from millions of years ago is essential for understanding the planet’s intrinsic climate change mechanisms. Ed Brook, director of COLDEX and a paleoclimatologist at OSU, remarked that the discovery surpassed expectations, as they had originally aimed to find ice no older than 3 million years. Plans are in motion for a COLDEX team to revisit Allan Hills to gather additional samples and potentially uncover even more ancient ice.
The team has formulated a long-term study of the area, with the goal of pushing back the records even further in time, aiming to conduct this research from 2026 to 2031. For additional information regarding their research and its implications, the complete study can be found in the Proceedings of the National Academy of Sciences. Photos from the mission, including the famous raising of the Foro Drill in Allan Hills, underscore the importance of this endeavor.