Researchers Drop a Camera Into a 300-Foot Hole in Antarctica to Find Earth’s Oldest Ice. The Results Were Baffling

In East Antarctica’s Victoria Land, not far from the Ross Ice Shelf, the thick ice pack hides a time capsule dating millions of years. This ice projects upwards and a steep topography materializes like ice castles. When paleoclimatologist, Julia Marks Peterson visited the site as a part of the US project, Center for OLDest Ice Exploration (COLDEX), she came across a rocky outcrop jutting upwards from the crystalline blue glacial icefield of Allan Hills. In 2019, a COLDEX researcher named Austin Carter (@austincarter642) discovered an ice dating slightly over 2 million years ago. But this time, Peterson and her team have stumbled upon an even older ice, 4 million years old to be precise, as she reported in a press release.

In December 2022, Carter posted a TikTok video capturing a camera’s journey as it hurtled down into the Allan Hills ice core in the East Antarctic Ice Sheet. People likened the camera’s time travel with metaphors of “Star Wars time warp,” “colonoscopy,” “magic school bus,” and “interdimensional portal.” The objective of this drill, he said, was to “understand the fundamentals of the climate change system.”  As the camera plummeted deep down through a hole the size of a dinner plate, it revealed eerie snapshots of azure glacial ice settled in layers. Carter said the oldest ice sample they could lay their hands on, was dated to about 2.7 million years old.

In a recent ice drill, Peterson, who is a PhD candidate from Oregon State University, reported that they had found the “oldest ice ever.” She and her team conducted this expedition by drilling a cylinder into the ice core, pulling out chunks of glacial ice, and then dating the air bubbles trapped in the extracted ice for greenhouse gases like carbon dioxide. Indeed, the team found bubbles that trapped carbon dioxide, which they believe, came from the respiration of microbes lurking deep in the ice column. Studying these carbon dioxide layers would help scientists figure out how glacial cycles shifted and changed over the past century. “These past warm periods may provide a look into what cycles will be like towards the end of the century,” Peterson said.

This was the fourth season of COLDEX’s excavation in the Allan Hills terrain. They didn’t have to drill too deep though. Just a 100-metre (0.62-mile) hole was enough to combat the 2019 discovery of old ice. Once the samples of ice core were extracted, they were sent to the National Science Foundation Ice Core Facility in Denver, Colorado for noble gas analysis. To examine the dating of the ice, Sarah Shackleton, a paleoclimatologist at the Woods Hole Oceanographic Institution, investigated the argon isotopes contained in its air bubbles.

According to Science, the extracted ice cores revealed some samples dating to the Pliocene, which ended about 2.6 million years ago with the start of the ice ages. Scientists believe that the high levels of carbon dioxide were responsible for this Pliocene. About 1.2 million years ago, something caused the ice ages to become longer and more intense, from 40,000-year cycles to deeper 100,000-year cycles. This caused the ice sheets to become thicker, deeper, and denser. To examine the chronology further, the scientists would require bigger pieces of ice, which they will collect in their upcoming COLDEX seasons. Peterson said the COLDEX team will continue to drill more ice cores from the Alan Hills and the Elephant Moraine to find old ice hiding somewhere in the ice field. 

You can follow Austin Carter (@austincarter642) on TikTok for more videos of his Antarctic adventures!