Ice coring
An ice core is a core sample of ice removed from a glacier, most commonly from the polar ice caps of Antarctica, Greenland or from high mountain glaciers elsewhere. As the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper, and an ice core contains ice formed over a range of years. The properties of the ice or inclusions within the ice can then be used to reconstruct a climatic record over the age range of the whole coring (from several thousands years in mountains glaciers up to 800 000 years in the Antarctic ice cap).
