Antarctic teams drill oldest ice cores yet in search of climate clues

More than a century ago, explorers from several countries raced to reach the globe’s southernmost point, driven by fierce international rivalries. Now, a new race is under way in Antarctica, this time motivated by the need to understand one of the gravest threats facing humanity.

While other ancient climate records exist, only the ancient ice near the poles holds a perfect record of the atmosphere’s carbon dioxide levels and temperature.