Discovering the Past to Predict the Future

Antarctica, the world’s most unforgiving continent, continues to challenge modern explorers with its relentless extremes. Yet, it is here that Dr. Joel Pedro and his team are pushing forward with an ambitious project to drill into ice that formed more than a million years ago. Despite setbacks and delays, their resolve remains unshaken. This summer, after years of meticulous planning, their quest is finally bearing fruit.

Confronting Elemental Extremes

High on the Antarctic plateau, where temperatures plummet to -30C during the day, Pedro leads Australia’s Million Year Ice Core project. The goal? To extract ice cores containing air bubbles from epochs long past, offering a window into Earth’s ancient climate. These samples will provide crucial data on atmospheric conditions when CO2 levels were lower, helping scientists predict future changes as human activity drives up carbon emissions.

The last season was particularly challenging. A 500-tonne convoy had to traverse 1,200km inland from Casey research station to reach Little Dome C, the initial drilling site. However, a significant portion of the team fell ill with Covid, leading to evacuations and a five-week delay. Adding to the difficulties, inclement weather at Casey further postponed operations. Ultimately, the decision was made to postpone drilling until the following year.

A Strategic Pivot

In light of these challenges, Pedro and his colleagues faced a critical choice: wait another year to resume drilling at Little Dome C or relocate to a potentially richer site. New research suggested that Dome C North, located 45km away, harbored ice up to 3.2km thick, possibly dating back 2 million years. This revelation provided a silver lining to the previous season’s frustrations. After careful deliberation, they opted to shift sites, a decision that could yield unprecedented scientific discoveries.

“It was a tough call,” Pedro admits, “but the potential rewards outweighed the risks. We’re now positioned to uncover ice older than anything previously found, which will significantly enhance our understanding of Earth’s climate history.”

Forging Ahead

In December, a massive 642-tonne convoy set out from Casey station, arriving at Dome C North on Christmas Eve. The team was greeted by a festive celebration hosted by the French and Italians at nearby Concordia station. By New Year’s Eve, the scientific and drilling teams had flown in, ready to erect a permanent drill shelter designed to withstand temperatures as low as -80C.

Drilling officially commenced in early January. Within two days, the team had reached a depth of 80 meters, extracting ice cores that provide a climate record spanning 4,000 years. Over the next five years, they aim to drill down more than 3km, retrieving three-meter-long cylinders of ice. Each core will be meticulously processed, analyzed, and eventually transported to Australia for further examination.

Unveiling Climate Mysteries

The ice cores hold secrets about Earth’s past, including oxygen isotopes that indicate temperature changes, chemical traces of volcanic eruptions, and fluctuations in greenhouse gas levels. If successful, this project will extend the climate record beyond the mid-Pleistocene transition, a pivotal period when Earth’s ice-age cycles shifted. Understanding this era is crucial for validating climate models used to forecast future changes.

“This work is vital for predicting how our planet will respond to rising CO2 levels,” Pedro explains. “By unlocking the past, we can better prepare for the future. The knowledge gained from these ancient ice cores will contribute significantly to our understanding of Earth’s long-term climate stability.”