Ice samples more than 1.5 million years old could reveal the secrets of climate change

It took international cooperation, four years of drilling, and millions of dollars to extract a 2,800-meter-long ice core from East Antarctica. “The ice was cut into one-meter sections and transported by ship, then in a refrigerated van, to Cambridge,” the British Antarctic Survey (BAS) reports, the BBC .

The samples extracted from a depth of 2,800 meters are believed to be at least 1.5 million years old, and the treasures they contain could “revolutionize” what we know about climate change. “This is a completely unknown period in our planet’s history,” explains Professor Liz Thomas, head of ice core research at BAS, the British national operator in Antarctica.

Over seven weeks, the team of scientists will “slowly melt the ice,” releasing “ancient dust, volcanic ash, and even tiny marine algae called diatoms, trapped when the water turned to ice,” the British broadcaster said. “These materials can tell scientists about wind patterns, temperature, and sea levels more than a million years ago.”

Liz Thomas's team could notably confirm the existence of a period, more than 800,000 years ago, "when carbon dioxide concentrations could have been naturally as high, or even higher, than today," the BBC points out. "This could help them understand the future of our planet" in the face of global warming .

“Our climate system has gone through so many different changes that we really need to be able to go back in time to understand these different processes and tipping points,” says Thomas.

The BAS's work could also help scientists "understand a mysterious change called the Middle Pleistocene transition, which occurred between 800,000 and 1.2 million years ago when the planet's glacial cycles suddenly changed."

The alternation between warm and ice periods used to occur every 41,000 years, “but it suddenly jumped to 100,000 years,” explains the BBC . The cause of this change is one of the “most exciting unsolved questions” in climate science, says Ms. Thomas.