Highest altitude ice core taken

The highest altitude on Earth at which an ice core has been extracted is 8,020 metres (26,312 feet) above sea level, taken from the South Col glacier on Mount Everest in Nepal - just above Camp IV and 828 metres (2,717 feet) below the summit of the world's highest mountain - in May 2019. The complex operation involved a team of more than 30 scientists (supported by a team of Sherpas) who trekked across Everest’s southern flank with a specially modified drill system as part of the Perpetual Planet Everest Expedition, backed by National Geographic and Rolex.

In charge of the ice core operation was Polish glaciochemist Mariusz Potocki of the Climate Change Institute at the University of Maine, USA. The 8,020-m-high ice core was 10 m (32 ft 10 in) in length and could date back as far as 2,000 years. It's hoped that, once analysed, the core (described as a "buried weather station") could reveal vital information about human pollution and climate change across the centuries.

During the same expedition, the team also set a record for placing the highest weather station, at 8,430 m (27,657 ft) asl. Anything above 8,000 m (26,247 ft) is dubbed the “death zone” owing to the huge depletion of oxygen in the air at this altitude and also the high number of fatalities among mountaineers in this particularly perilous section of the mountain.

Ice cores have been taken from glaciers on every continent and are one of the most valuable archives of past climate and environmental conditions, typically going back thousands of years.

In Antarctica, scientists have extracted ice thought to be 2.7 million years old, with the longest continuous (i.e., uninterrupted) ice core record being 800,000 years.