Beyond EPICA Links 1.2-Million-Year Ice Core to 50-ppm CO2 Shift in Ice Age Cycle
Updated
Updated · dongascience.com · May 8
Beyond EPICA Links 1.2-Million-Year Ice Core to 50-ppm CO2 Shift in Ice Age Cycle
2 articles · Updated · dongascience.com · May 8
A 1.2-million-year Antarctic ice core captured a rapid atmospheric CO2 jump of about 50 ppm around 950,000 years ago, a change researchers say aligns with the start of the first 100,000-year ice age cycle.
The Beyond EPICA team said the signal points to stronger deep-ocean carbon storage, after carbon-isotope analysis found no sign of a large release of deep-sea carbon into the atmosphere.
The core, drilled 2.8 km deep at Little Dome C over 10 years, also recorded a subsequent fall to 170 ppm—the lowest CO2 level yet confirmed in a continuous ice-core record.
That evidence challenges the regolith hypothesis for the Mid-Pleistocene Transition: if disappearing subglacial debris had driven the shift, researchers said the change would have had to be nearly instantaneous, and CF4 data showed no supporting signal.
Independent boron-based reconstructions from seafloor sediments showed similar atmospheric changes, strengthening the case that carbon-cycle shifts helped drive Earth's move from 40,000-year to 100,000-year glacial cycles.
Can a million-year-old ice core finally solve the mystery of why Earth's ice age rhythm changed?
If ancient CO2 shifts remade our planet, what does our current carbon surge mean for Earth's future?
Unlocking 1.2 Million Years of Climate History: The Beyond EPICA Antarctic Ice Core Breakthrough and Its Impact on Understanding Earth's Past and Future
Overview
The Beyond EPICA – Oldest Ice initiative, launched in 2019, is a major international scientific effort to recover the world’s oldest continuous ice cores from Antarctica. European and Australian teams developed specialized drills to tackle the harsh Antarctic conditions, working at separate sites to ensure data integrity and avoid errors from ice flow disturbances. By recovering multiple, independent ice cores, the project greatly increases the chances of finding ice that is at least 1.2 million years old. This collaborative approach aims to unlock new insights into Earth’s ancient climate history and the changes that shaped our planet.