Antarctic ice core unlocks 1.2 million years of uninterrupted climate history, setting new record

Humans have been recording the weather for thousands of years. However, Antarctic ice has been around for more than a million people.

An international team of scientists has extracted a 1.74-mile (2.8 km)-long ice core in Antarctica, reaching the foundation of the frozen continent. The core represents a chronological record of Earth’s climate and atmosphere, with the oldest ice dating back 1.2 million years, if not longer. The achievement, which was announced in A statement With the “Beyond EPICA – Oldest Ice” project, it is expected to provide insight into one of the most enduring questions in climate science.

It should be noted that this record does not make it the oldest ice core ever recovered, but rather that recognition goes to A 2.7 million year old ice core It was recovered in 2017. What makes Beyond EPICA special is its continuous, high-resolution climate record spanning 1.2 million years, providing important insights into ancient atmospheric conditions and glacial cycles.

“We have witnessed a historic moment for climate and environmental science,” said Carlo Barbanti of Ca’ Foscari University in Venice, coordinator of the Beyond EPICA programme. The core was recovered during the project’s fourth Antarctic expedition. “This is the longest continuous record of our past climate from an ice core, and could reveal the link between the carbon cycle and the temperature of our planet.”

Between 900,000 and 1.2 million years ago, glacial cycles shifted from 41,000 years to 100,000 years, a shift known as the mid-Pleistocene transition. The Beyond EPICA project aims to better understand this ancient climate phenomenon.

Led by the Institute of Polar Sciences of the Italian National Research Council (ISP-CNR), scientists worked for more than 200 days, drilling into the ice and processing ice cores at a remote site in East Antarctica called Little Dome C. With an average summer temperature Mild -31°F (-35°C).

“From preliminary analyzes recorded at Little Dome C, we have a strong indication that the top 2,480 meters (1.54 miles) contain a climate record dating back 1.2 million years in a high-resolution record where up to 13,000 years are compressed into one.” “It’s about a meter of ice,” says Julian Westhoff, a postdoctoral researcher at the University of Copenhagen and lead scientist in this field for the EPICA project. .

The deeper, older parts of the core, which were closest to the rock, were made of ancient ice that was “heavily deformed, possibly mixed or refrozen of unknown origin,” as well as boulders from the rock itself. This section can enhance scientists’ understanding of the frozen ice beneath the Antarctic ice sheet, the history of glaciation in the Antarctic region, and the last time the continent was ice-free.

The project still faces significant hurdles, particularly the logistical challenge of transporting fragmented ice samples to the laboratory without risking melting.

“The precious ice samples extracted during this campaign will be transported to Europe on board the icebreaker Laura Passi, with the cold chain maintained at -50°C (-58°F),” said Gianluca Bianchi Fasani, head of the Italian National Ice Monitoring Agency. Logistics for new technologies, energy and sustainable economic development (ENEA) for Beyond EPICA. “To achieve this goal, a strategy has been developed that includes the design of specialized cold containers and careful scheduling of air and sea assets of the National Antarctic Research Program (PNRA).”

Once the fragmented ice core finds its way into a (very cold) laboratory, it remains to be seen what secrets researchers will uncover in the ancient climate record.