The Erebus Ice Tongue, coming off the Erebus Glacier from 3,800 m (12,500 ft). Mount Erebus, Ross Island, Antarctica. The ice tongue is protruding into McMurdo Sound (frozen in this image).

An ice tongue exists when there is a narrow floating part of a glacier that extends out into a body of water beyond the glacier's lowest contact with the Earth's crust. An ice tongue forms when a glacier that is confined by a valley moves very rapidly out into a lake or ocean, relative to other ice along the coastline. When such ice surges past adjacent coastal ice, the boundary experiences physical forces described as "shearing".^[1]

Ice tongues can gain mass from water freezing at their base, by snow falling on top of them, or by additional surges from the main glacier. Mass is then lost by calving or by melting. Icebergs are often formed when ice tongues break off in part or wholly from the main glacier.^[2] A few examples of ice tongues are the Erebus Ice Tongue, Drygalski Ice Tongue, and Thwaites Ice Tongue.

References

• "Erebus Ice Tongue". NASA Earth Observatory. Archived from the original on 2006-10-01. Retrieved 2006-05-19.