ice core

noun

1. A core sample removed from an ice sheet, most commonly from the polar ice caps of Antarctica, Greenland or from high mountain glaciers elsewhere, the properties of which can be used to reconstruct a climatic record of a given area.

   “A team including climate scientists and microbiologists from Ohio State University took two ice cores from the summit of the Guliya ice cap, at 22,000 feet above sea level, in western China in 2015.”