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The Erebus Ice Tongue is a mountain outlet glacier and the seaward extension of Erebus Glacier from Ross Island. It projects into McMurdo Sound from the Ross Island coastline near Cape Evans, Antarctica. The glacier tongue varies in thickness from at the snout to at the point where it is grounded on the shoreline.〔("Calving of Erebus Glacier Tongue ), Nature Magazine. August 16, 1990.〕 Explorers from Robert F. Scott's Discovery Expedition (1901–1904) named and charted the ice tongue.〔(Australian Antarctic Data Centre ), Antarctic Gazetteer Name Details.〕 Erebus Ice Tongue is about high and is centred upon 77.6 degrees south latitude, 166.75 degrees east longitude.〔(“Erebus Ice Tongue,” ) NASA Jet Propulsion Laboratory, California Institute of Technology. Undated.〕 The portion of the ice tongue extending beyond the shoreline or grounding line floats upon the water. Ice tongues emerge when a glacier ice stream flows rapidly (relative to surrounding ice) into the sea or a lake, usually in a protected area. For instance, Capes Evans and Royds extending from Ross Island protect the Erebus Ice Tongue from the open waters of the Ross Sea. Hut Point Peninsula to the south helps deflect icebergs propelled by prevailing southerly winds. The long, narrow Erebus ice stream drains from the western slope of Mount Erebus, an active volcano rising in elevation. The mountain constantly replenishes the glacial ice stream, as annual snow fall exceeds annual snow melt. The Erebus Ice Tongue is a dynamic structure subject to a host of internal and external stresses which affect its shape, size, and durability.〔Pyne, Stephen J. The Ice: A Journey to Antarctica. Originally published by the University of Iowa Press, 1986.〕 ==Ice tongue harbors== The frozen sea ice of Erebus Bay surrounding the Erebus Ice Tongue typically breaks out during the summer. This exposes the ice tongue to pounding waves from McMurdo Sound. Moreover, such wave action also impacts the ice caves accessed along the leading edges of the ice tongue. The ice caves include inter-locked crevasses covered by snow bridges. The ice caves are a popular attraction for residents from nearby the McMurdo Station and Scott Base research stations. Visitors report observing stalactite-like icicles on the cave ceilings, as well as intricate ice crystals.〔(TIGER in Antarctica )〕 Sunlight filtering through ice into the caves bathes the interiors with diffuse blue light.〔(The Ice Cave Tour )〕 Contemporary cave explorers who squeezed through a narrow tunnel several hundred feet long to emerge into a large cavern describe their Erebus Ice Tongue experience as:
Scientists funded by a National Science Foundation grant have retrieved rare underwater views of the Erebus Ice Tongue caves by mounting cameras on Weddell seals. Images revealed rocks and dead fish frozen into the ice. Video also depicted other Weddell seals that appeared to use the underwater caves as hiding places from predators such as the orca (or killer whale) and the leopard seal.〔("The Foraging Biology of Weddell Seals," ) 2001 Antarctica Expedition.〕 Weddell seals are commonly sighted by visitors to the Erebus Ice Tongue. Each year 300 to 400 Weddell seal pups are born to a colony of seals that live in adjoining Erebus Bay. The seals have been distinctively marked and re-sighted since 1969.〔(Ph.D. Research Assistantship - Weddell seal population dynamics ), Montana State University job announcement. See also: ()〕 The nearly 40-year study represents one of the longest field investigations of its type, according to a Montana State University report.〔(Montana EPSCoR in Review ), January 2003, Issue 2.〕 Emperor and Adelie penguins are also found in the vicinity of the Erebus Ice Tongue. Adelie are particularly noted for their rookeries on Erebus Bay's rocky north shore at nearby Cape Royds. Penguins, like the Weddell seal, are preyed upon by orcas and leopard seals. The presence of penguins also attracts the predatory skua seabird. Scarce mention of the ice tongue's surface, which is more than a mile wide,〔(Antarctic Glaciers ), by Harry Fielding Reid Geographical Review. American Geographical Society 1924.〕 is made in popular literature. A notable exception is in Ernest Shackleton's book, South! The leader of a December 1916 search party seeking fellow explorers missing in vicinity of the ice tongue made the following report to Shackleton:
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