In 1929, a team carrying a sun compass and a National Geographic Society flag soared above the Antarctic wilderness in an extraordinary scientific feat. Explorer Richard E. Byrd led the perilous first flight over the South Pole, and photographed at least 150,000 square miles of Antarctica along the way.

Nearly a century later, glaciologist and National Geographic Explorer Alison Criscitiello embarked on her own arduous journey, harnessing technology in grueling conditions to unlock secrets of the Earth’s past and insights about today’s climate challenges. She and her team ascended Canada’s highest peak and excavated an ice core containing perhaps 30,000 years of data, as part of the National Geographic and Rolex