ice tongue

{{Short description|Long, narrow sheet of ice projecting from a coastline}}

File:ErebusIceTongue ASTER 30nov2001.jpg, coming off the Erebus Glacier from {{Convert|3800|m|ft|-2|abbr=on}}. Mount Erebus, Ross Island, Antarctica. The ice tongue is protruding into McMurdo Sound (frozen in this image).]]

An ice tongue or glacier 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".{{Cite web |last=Canada |first=Environment and Climate Change |date=2010-09-27 |title=Ice glossary |url=https://www.canada.ca/en/environment-climate-change/services/ice-forecasts-observations/latest-conditions/glossary.html |access-date=2023-05-15 |website=www.canada.ca}}

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.{{cite web |last1=McDonald |first1=Neil |title=Ice tongues on the Greenland Ice Sheet |url=https://www.antarcticglaciers.org/glaciers-and-climate/changing-greenland-ice-sheet/ice-tongues-on-the-greenland-ice-sheet/ |website=AntarcticGlaciers.org |date=7 February 2022 |access-date=8 July 2022}}

A few examples of ice tongues are the Erebus Glacier Tongue, Drygalski Ice Tongue, and Thwaites Ice Tongue.