Highest altitude ice core taken

The world’s highest ice core was taken from the very summit of Mount Everest (the world's highest mountain) on 22 May 2026 by a joint Chinese-Nepali expedition dubbed "Core of the Summit" at an altitude 8,848.86 m (29,031 ft).

The apex of Everest, aka Sagarmāthā or Chomolungma, is covered by snow and ice year-round as temperatures hardly ever rise above freezing. The depth of the frozen patch on the summit had previously only been estimated as a few metres, but the Chinese-Nepali team used radar surveys to estimate a depth of around 9.5 m (31 ft) and then extracted a "full depth" core through the whole ice column.

This surpassed the previous record of 8,020 m (26,312 ft) for an ice core taken from the South Col glacier on Mount Everest – just above Camp IV and 828 m (2,717 ft) below the summit – 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.

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. It’s not yet clear how old the ice is at the bottom of the Everest core but it will provide a valuable archive of changes in climate and atmospheric conditions high up in the atmosphere. Although it may seem like this record could never be broken, Everest is increasing in height by around 4 mm each year. Hence, a team returning in 50 years would be drilling at an altitude that is 20 cm (8 in) higher!