Pobeda Ice Island, original Russian name остров Победы (остров = ''Island'', Победа = ''Victory'', meaning Pobeda Island or Victory Island), is an ''ice island'' in the Mawson Sea. It is located off the coast of

Queen Mary Land Queen Mary Land or the Queen Mary Coast () is the portion of the coast of Antarctica lying between Cape Filchner, in 91° 54' E, and Cape Hordern, at 100° 30' E. It is claimed by Australia as part of the Australian Antarctic Territory. It ...

East Antarctica East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctic continent, lying on the Indian Ocean side of the continent, separated from West Antarctica by the Transantarctic Mountains. It lies almost ...

. This island, which exists periodically, is formed by the running aground of a

tabular iceberg An iceberg is a piece of freshwater ice more than 15 m long that has broken off a glacier or an ice shelf and is floating freely in open (salt) water. Smaller chunks of floating glacially-derived ice are called "growlers" or "bergy bits". The ...

Periodic formation

The ice island is created and vanishes periodically. It is created by the calving of an enormous block of ice from

Denman Glacier Denman Glacier is a glacier wide, descending north some , which debouches into the Shackleton Ice Shelf east of David Island, Queen Mary Land. It was discovered in November 1912 by the Western Base party of the Australasian Antarctic Expedit ...

, located in the eastern part of Shackleton Ice Shelf. The resulting tabular iceberg drifts northwest until it runs aground upon a

shoal In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material and rises from the bed of a body of water to near the surface. It ...

north of the ice shelf. The iceberg remains locked in this position there for a decade or more, until has remodeled enough to free itself from the shoal. It then drifts into the

open ocean The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or wa ...

, where it breaks into fragments. These iceberg fragments eventually melt as they drift into warmer waters. The floating tongue of the Denman Glacier, fed by ice from the interior of Antarctica, advances until a new large berg is calved about every 40 to 50 years.

Data

Pobeda Ice Island is variable in its dimensions, but is commonly up to long and wide, with an area of . The term "

island An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...

" is technically incorrect, since this geographic feature is in reality a tabular iceberg with nearly vertical sides and a flat top.

Laws of physics Scientific laws or laws of science are statements, based on repeated experiments or observations, that describe or predict a range of natural phenomena. The term ''law'' has diverse usage in many cases (approximate, accurate, broad, or narrow) ...

dictate that 11% of an iceberg will extend above the water level (in salt water), while the remainder will be submerged. In the case of Pobeda Ice Island, whose flat surface is roughly above sea level, this means that the iceberg extends to a depth of roughly below sea level, and its total height is approximately . The further implication is that the ocean floor is also roughly below sea level, at the point of the shoal.

History

At this position, an ice island was first sighted by the

United States Exploring Expedition The United States Exploring Expedition of 1838–1842 was an exploring and surveying expedition of the Pacific Ocean and surrounding lands conducted by the United States. The original appointed commanding officer was Commodore Thomas ap Catesb ...

, led by

Charles Wilkes Charles Wilkes (April 3, 1798 – February 8, 1877) was an American naval officer, ship's captain, and explorer. He led the United States Exploring Expedition (1838–1842). During the American Civil War (1861–1865), he commanded ' during th ...

, in February 1840. It prevented his westward passage around the Antarctic coast, and he named it ''Termination Land''.

Douglas Mawson Sir Douglas Mawson OBE FRS FAA (5 May 1882 – 14 October 1958) was an Australian geologist, Antarctic explorer, and academic. Along with Roald Amundsen, Robert Falcon Scott, and Sir Ernest Shackleton, he was a key expedition leader duri ...

renamed the island ''Termination Ice Tongue'' when he encountered it on the 1911-13

Australasian Antarctic Expedition The Australasian Antarctic Expedition was a 1911–1914 expedition headed by Douglas Mawson that explored the largely uncharted Antarctic coast due south of Australia. Mawson had been inspired to lead his own venture by his experiences on Ernest ...

. No island was noted however at that location, when he returned during his 1929-31 BANZARE expedition. A Soviet Expedition came across the island in 1960 and renamed it again, this time as ''Pobeda Ice Island'', named for Soviet victory over the Axis powers in the

Great Patriotic War The Eastern Front of World War II was a theatre of conflict between the European Axis powers against the Soviet Union (USSR), Poland and other Allies, which encompassed Central Europe, Eastern Europe, Northeast Europe (Baltics), and S ...

. They even established a temporary research station on the island. Pobeda disappeared sometime in the 1970s, to be replaced by a new berg that calved in 1985. That one also disappeared in 2003 or 2004. There is currently no ice island at this location.

Pobeda Canyon

About north of Pobeda Ice Island lies ''Pobeda Canyon'', an

oceanic trench Oceanic trenches are prominent long, narrow topographic depressions of the ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers in length. There are about of oceanic tre ...

so named in 1956 by A. P. Lizitsi

It is located between and .

External links

coordinates, height, station operations

Pobeda Station

overview of maps

Literature