iceberg
American Heritage Dictionary:
Top
ice·berg
(īs'bûrg') 
n.
n.
- A massive floating body of ice broken away from a glacier. Only about 10 percent of its mass is above the surface of the water.
- Informal. A cold, aloof person.
[Partial translation of Dutch ijsberg, from Middle Dutch ijsbergh : ijs, ice + bergh, mountain.]
Britannica Concise Encyclopedia:
Top
iceberg
Floating mass of ice that has broken from the seaward end of a glacier or a polar ice sheet. Icebergs are typically found in open seas, especially around Greenland and Antarctica. They form mostly during each hemisphere's spring and summer, when warmer weather increases the rate of calving (separation) of icebergs at the boundaries of the Greenland and Antarctic ice sheets and smaller outlying glaciers. In the Northern Hemisphere, about 10,000 icebergs are produced each year from the Greenland glaciers, and an average of 473 flow into the North Atlantic shipping lanes, where they are a hazard to navigation, especially because only about 10 of an iceberg is exposed above the surface of the sea.
For more information on iceberg, visit Britannica.com.
Top
A large mass of glacial ice broken off and drifted from parent glaciers or ice shelves along polar seas. Icebergs should be distinguished from polar pack ice which is sea ice, or frozen sea water, though rafted or hummocked fragments of the latter may resemble small bergs. See also Glaciology; Sea ice.
Icebergs are classified by shape and size. The terms used are arched, blocky, dome, pinnacled, tabular, valley, and weathered for berg description, and bergy-bit and growler for berg fragments ranging smaller than cottage size above water. The lifespan of an iceberg may be indefinite while the berg remains in cold polar waters, eroding only slightly during summer months. But under the influence of ocean currents, an iceberg that drifts into warmer water will disintegrate rapidly.
In the Arctic, icebergs (see illustration) originate chiefly from glaciers along Greenland coasts. It is estimated that a total of about 16,000 bergs are calved annually in the Northern Hemisphere, of which over 90% are of Greenland origin; but only about half of these have a size or source location to enable them to achieve any significant drift. No icebergs are discharged or drift into the North Pacific Ocean or its adjacent seas, except a few small bergs each year that calve from the piedmont glaciers along the Gulf of Alaska.
Arctic iceberg, eroded to form a valley or dry-dock type: grotesque shapes are common to the glacially produced icebergs of the North.
In the Southern Ocean, bergs originate from the giant ice shelves all along the Antarctic continent. These result in huge, tabular bergs or ice islands several hundred feet high and often over a hundred miles in length, which frequent the entire waters of the Antarctic seas.
Oxford Dictionary of Geography:
Top
iceberg
A huge mass of ice, floating in the sea and usually broken off from a glacier. The depth of an iceberg is often far greater than that of an ice floe.
Columbia Encyclopedia:
Top
iceberg
iceberg, mass of ice that has become detached, or calved, from the edge of an ice sheet or glacier and is floating on the ocean. Because ice is slightly less dense than water about one ninth of the total mass of a berg projects above the water. Greenland and other N Atlantic icebergs are usually peaked and irregular in shape; Antarctic icebergs are tabular, with flat tops and steep sides. Icebergs differ from other ocean ices: sea ice is formed directly from the freezing of ocean water; pack ice is tightly packed fragments of sea ice; ice floes are small, floating ice fragments that separate from pack ice; and fast ice is ice attached to a shore.
Greenland is the source of most of the icebergs in the N Atlantic, where the iceberg season lasts roughly from February to October. As a consequence of the loss of the Titanic through collision with an iceberg in 1912, a patrol of N Atlantic shipping channels was initiated in 1914 by the international agreement of 16 nations. Patrols use planes and surface vessels equipped with radar, loran, and underwater sound equipment. A constant census of bergs is maintained, and the location of an iceberg is reported to any ship in its vicinity.
Word Tutor:
Top
iceberg
IN BRIEF: A very large piece of ice that has broken off from a glacier.
The mind is an iceberg — it floats with only one-seventh of its bulk above water.
— Sigmund Freud (1856-1939), Austrian founder of psychoanalysis.
LearnThatWord.com is a free vocabulary and spelling program where you only pay for results!
Top
A large piece of ice that has broken away from a glacier at the shore and floated out to sea.
Random House Word Menu:
Top
categories related to 'iceberg'
- Materials, Formations, and Substances - iceberg: mass of ice detached from glacier and floating at sea
- Coastal Land, Islands, and the Sea - iceberg: large mass of ice broken off from glacier, floating in sea
- lettuce
- Behavior or Personality
See crossword solutions for the clue Wikipedia on Answers.com:
Top
Iceberg
For other uses, see Iceberg (disambiguation).
An iceberg is a large piece of ice from freshwater that has broken off from a snow-formed glacier or ice shelf and is floating in open water.[1][2] It may subsequently become frozen into pack ice. Alternatively, it may come to rest on the seabed in shallower water, causing ice scour (also known as ice gouging) or becoming an ice island.
|
Contents
|
Etymology
The word "iceberg" is a partial loan translation from Dutch ijsberg, literally meaning ice mountain,[3] cognate to Danish Isbjerg, German Eisberg, Low Saxon Iesbarg and Swedish Isberg.
Overview
Because the density of pure ice is about 920 kg/m³, and that of sea water about 1025 kg/m³, typically only one-ninth of the volume of an iceberg is above water. The shape of the underwater portion can be difficult to judge by looking at the portion above the surface. This has led to the expression "tip of the iceberg", for a problem or difficulty that is only a small manifestation of a larger problem.
Icebergs generally range from 1 to 75 metres (3.3 to 246 ft) above sea level and weigh 100,000 to 200,000 metric tons (110,000 to 220,000 short tons). The largest known iceberg in the North Atlantic was 168 metres (551 ft) above sea level, reported by the USCG icebreaker East Wind in 1958, making it the height of a 55-storey building. These icebergs originate from the glaciers of western Greenland, and may have an interior temperature of -15 to -20 °C (5 to -4 °F).[4]
Though usually confined by winds and currents to move close to the coast, the largest icebergs recorded have been calved, or broken off, from the Ross Ice Shelf of Antarctica. Iceberg B-15, photographed by satellite in 2000, measured 295 by 37 kilometres (183 by 23 mi), with a surface area of 11,000 square kilometres (4,200 sq mi). The mass was estimated around three billion tonnes. The largest iceberg on record was an Antarctic tabular iceberg of over 31,000 square kilometres (12,000 sq mi) [335 by 97 kilometres (208 by 60 mi)] sighted 150 miles (240 km) west of Scott Island, in the South Pacific Ocean, by the USS Glacier on November 12, 1956. This iceberg was larger than Belgium.[5]
When an iceberg melts, it makes a fizzing sound called "Bergie Seltzer". This sound is made when compressed air bubbles trapped in the iceberg pop. The bubbles come from air trapped in snow layers that later became glacial ice.[4]
Classification
Size
Names for various sizes of iceberg are not universal, but usually follow a similar pattern. The size classification in the table below is used by the International Ice Patrol:[6]
| Size Category | Height | Length |
|---|---|---|
| Growler | Less than 1 metre (3.3 ft) | Less than 5 metres (16 ft) |
| Bergy Bit | 1–5 metres (3.3–16 ft) | 5–15 metres (16–49 ft) |
| Small | 5–15 metres (16–49 ft) | 15–60 metres (49–200 ft) |
| Medium | 15–45 metres (49–148 ft) | 60–120 metres (200–390 ft) |
| Large | 45–75 metres (148–246 ft) | 120–200 metres (390–660 ft) |
| Very Large | Over 75 metres (246 ft) | Over 200 metres (660 ft) |
Recent large icebergs
- Iceberg B-15 11,000 km² (4,200 sq mi), 2000
- Iceberg A-38, about 6,900 km² (2,700 sq mi), 1998[7]
- Iceberg B-15A, 3,100 km² (1,200 sq mi), broke off 2003
- Iceberg C-19, 5,500 km² (2,100 sq mi), 2002
- Iceberg B-9, 5,390 km² (2,080 sq mi), 1987
- Iceberg D-16, 310 km² (120 sq mi), 2006
- Ice sheet, 260 km² (100 sq mi), broken off of Petermann Glacier in northern Greenland on Aug 5, 2010, considered to be largest Arctic iceberg since 1962.[8] About a month later, this iceberg split into two pieces upon crashing into Joe Island in the Nares Strait next to Greenland.[9] In June 2011, large fragments of the Petermann Ice Islands were observed off the Labrador coast.[10]
- Iceberg B-17B 140 km² (54 sq mi), 1999, shipping alert issued December 2009.[11]
Shape
In addition to size classification, icebergs can also be classified on the basis of their shape. The two basic types of iceberg forms are tabular and non-tabular. Tabular icebergs have steep sides and a flat top, much like a plateau, with a length-to-height ratio of more than 5:1.[12] This type of iceberg can be quite large, as in the case of Pobeda Ice Island. Antarctic icebergs formed by breaking off from an ice shelf, such as the Ross Ice Shelf or Filchner-Ronne Ice Shelf, are typically tabular. The largest icebergs in the world are formed this way.
Non-tabular icebergs have different shapes, and include:[13]
- Dome: An iceberg with a rounded top.
- Pinnacle: An iceberg with one or more spires.
- Wedge: An iceberg with a steep edge on one side and a slope on the opposite side.
- Dry-Dock: An iceberg that has eroded to form a slot or channel.
- Blocky: An iceberg with steep, vertical sides and a flat top. It differs from tabular icebergs in that its shape is more like a block than a flat sheet.
Monitoring
Icebergs are monitored worldwide by the U.S. National Ice Center (NIC), established in 1995, which produces analyses and forecasts of Arctic, Antarctic, Great Lakes and Chesapeake Bay ice conditions. More than 95% of the data used in its sea ice analyses are derived from the remote sensors on polar-orbiting satellites that survey these remote regions of the Earth.
The NIC is the only organization that names and tracks all Antarctic Icebergs. It assigns each iceberg larger than 10 nautical miles (19 km) along at least one axis a name composed of a letter indicating its point of origin and a running number. The letters used are as follows:[14]
- A – longitude 0° to 90° W (Bellingshausen Sea, Weddell Sea)
- B – longitude 90° W to 180° (Amundsen Sea, Eastern Ross Sea)
- C – longitude 90° E to 180° (Western Ross Sea, Wilkes Land)
- D – longitude 0° to 90° E (Amery Ice Shelf, Eastern Weddell Sea)
Iceberg B15 calved from the Ross Ice Shelf in 2000 and initially had an area of 11,000 square kilometres (4,200 sq mi). It broke apart in November 2002. The largest remaining piece of it, Iceberg B-15A, with an area of 3,000 square kilometres (1,200 sq mi), was still the largest iceberg on Earth until it ran aground and split into several pieces October 27, 2005. It has been determined that the cause of the breakup was an ocean swell generated by an Alaskan storm 6 days earlier and 13,500 kilometres (8,400 mi) away.[15]
History
In the 20th century, several scientific bodies were established to study and monitor the icebergs. The International Ice Patrol, formed in 1914 in response to the Titanic disaster, monitors iceberg dangers near the Grand Banks of Newfoundland and provides the "limits of all known ice" in that vicinity to the maritime community.
Technology history
Before April 1912 there was no system in place to track icebergs to guard ships against collisions. The sinking of the RMS Titanic, which caused the deaths of 1,514 of its 2,223 passengers, created the demand for a system to observe icebergs. For the remainder of the ice season of that year, the United States Navy patrolled the waters and monitored ice flow. In November 1913, the International Conference on the Safety of Life at Sea met in London to devise a more permanent system of observing icebergs. Within three months the participating maritime nations had formed the International Ice Patrol (IIP). The goal of the IIP was to collect data on meteorology and oceanography in order to measure currents, ice-flow, ocean temperature, and salinity levels. They published their first records in 1921, which allowed for a year-by-year comparison of iceberg movement.
New technologies monitor icebergs. Aerial surveillance of the seas in the early 1930s allowed for the development of charter systems that could accurately detail the ocean currents and iceberg locations. In 1945, experiments tested the effectiveness of radar in detecting icebergs. A decade later, oceanographic monitoring outposts were established for the purpose of collecting data; these outposts continue to serve in environmental study. A computer was first installed on a ship for the purpose of oceanographic monitoring in 1964, which allowed for a faster evaluation of data. By the 1970s, icebreaking ships were equipped with automatic transmissions of satellite photographs of ice in Antarctica. Systems for optical satellites had been developed, but were still limited by weather conditions. In the 1980s, drifting buoys were used in Antarctic waters for oceanographic and climate research. They are equipped with sensors that measure ocean temperature and currents. Side-Looking Airborne Radar (SLAR) made it possible to acquire images regardless of weather conditions. On November 4, 1995, Canada launched RADARSAT-1. Developed by the Canadian Space Agency, it provides images of Earth for both scientific and commercial purposes. This system was the first to use Synthetic Aperture Radar (SAR), which sends microwave energy to the ocean surface and records the reflections to track icebergs. The European Space Agency launched ENVISAT (an observation satellite that orbits the Earth's poles)[16] on March 1, 2002. ENVISAT employs Advanced Synthetic Aperture Radar (ASAR) technology, which can detect changes in surface height accurately. The Canadian Space Agency launched RADARSAT-2 in December in the year of 2007, which uses SAR and multipolarization modes and follows the same orbit path as RADARSAT-1.[17]
One important iceberg in history was the one that hit the RMS Titanic on the 14th of April 1912. It struck the right side of the Titanic, leaving shards of ice on the deck near the bow. Icebergs had been reported by other ships in the vicinity in the days leading up to the accident and yet the crew of the Titanic only saw the one that sunk them when they were almost on top of it. The night was clear and there was no moon out to illuminate the iceberg. The seas were unusually calm and the lack of wave action and spray around the waterline of the iceberg made it practically invisible that night. The sinking of the Titanic resulted in the death of 1,517 of the 2,200 passengers who were on board. An RMS Titanic survivor said "When the dawn rose I was stunned to see that we were surrounded by a veritable mountain range of icebergs. In the dark, they had been completely invisible. But in the rising dawn, they were everywhere. For objects so lethal, they were also majestic. And almost beautiful, in a horrid way." After the sinking of the Titanic, rules were introduced to ensure there were enough lifeboats to accommodate all passengers and crew of sea-going vessels. Monitoring of ice fields also began, in an attempt to prevent a repeat of the Titanic disaster.
See also
References
- ^ "Definitions of the word "Iceberg"". Google. http://www.google.com/search?hl=en&q=define%3Aiceberg&btnG=Google+Search. Retrieved 2006-12-20.
- ^ "Common Misconceptions about Icebergs and Glaciers". Ohio State University. http://beyondpenguins.ehe.osu.edu/issue/icebergs-and-glaciers/common-misconceptions-about-icebergs-and-glaciers. "Icebergs float in salt water, but they are formed from freshwater glacial ice."
- ^ "Iceberg". Online Etymology Dictionary. http://www.etymonline.com/index.php?search=iceberg&searchmode=none. Retrieved 2006-03-26.
- ^ a b "Facts on Icebergs". Canadian Geographic. http://www.canadiangeographic.ca/magazine/MA06/indepth/justthefacts.asp. Retrieved 2010-12-08.
- ^ "Antarctica shed a 208-mile-long berg in 1956". Polar Times 43: p. 18. 2005-01-20. http://www.usatoday.com/weather/resources/coldscience/2005-01-20-1956-antarctic-iceberg_x.htm.
- ^ "Ice, Weather, and Sea Surface Temperature Reports". International Ice Patrol. http://www.uscg.mil/LANTAREA/IIP/docs/VOOP.pdf. Retrieved 2009-01-14.
- ^ "Iceberg A-38B off South Georgia". Visible Earth. http://visibleearth.nasa.gov/view_rec.php?id=6831. Retrieved 2011-03-09.
- ^ "Huge ice sheet breaks from Greenland glacier". BBC. 2010-08-07. http://www.bbc.co.uk/news/science-environment-10900235. Retrieved 2011-03-09.
- ^ "Massive Iceberg Crashes Into Island, Splits in Two". http://www.aolnews.com/2010/09/11/giant-ice-island-splits-near-greenland/.
- ^ "Massive ice island heading for southern Labrador". CBC News. 2011-06-23. http://www.cbc.ca/news/canada/newfoundland-labrador/story/2011/06/23/nl-ice-labrador-623.html.
- ^ "Shipping alert issued over giant iceberg". Associated Press. 12-11-2009. http://www.msnbc.msn.com/id/34380916/ns/world_news-world_environment/.
- ^ "Sizes and Shapes of Icebergs". International Ice Patrol. http://www.uscg.mil/lantarea/iip/docs/AOS_2011.pdf. Retrieved 2006-12-20.
- ^ "Iceberg Physiology". Canadian Geographic. http://www.canadiangeographic.ca/magazine/ma06/indepth/nathistory.asp. Retrieved 2006-12-20.
- ^ "New Iceberg Breaks off Ronne Ice Shelf in Antarctica". NOAA. 15 October 1998. http://www.xs4all.nl/~carlkop/ronne.html. Retrieved 2011-03-09.
- ^ "Alaskan storm cracks giant iceberg to pieces in faraway Antarctica". http://www.physorg.com/news79026480.html.
- ^ "Envisat". European Space Agency. https://earth.esa.int/web/guest/missions/esa-operational-eo-missions/envisat. Retrieved 2011-03-09.
- ^ "Tracking Monsters". Canadian Geographic. http://www.canadiangeographic.ca/magazine/MA06/indepth/technology_side2.asp. Retrieved 2006-03-29.
External links
 |
Wikimedia Commons has media related to: Iceberg |
- Iceberg Finder Service for east coast of Canada
- Icebergs of The Arctic and Antarctic
"Iceberg". Collier's New Encyclopedia. 1921.
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
Translations:
Top
Iceberg
idioms:
- iceberg lettuce icebergsalat
- tip of the iceberg toppen af isbjerget
Français (French)
n. - (lit) iceberg, (fig) glaçon
idioms:
- iceberg lettuce laitue iceberg
- tip of the iceberg pointe de l'iceberg, (être) l'infime partie d'un tout
idioms:
- iceberg lettuce frischer Salat mit bleichem Salatkopf
- tip of the iceberg die Spitze des Eisbergs
Ελληνική (Greek)
n. - παγόβουνο, ογκόπαγος
idioms:
- iceberg lettuce είδος μαρουλιού
- tip of the iceberg η κορυφή του παγόβουνου
idioms:
- iceberg lettuce lattuga bianca
- tip of the iceberg la punta dell'iceberg
Português (Portuguese)
n. - monte (m) de gelo flutuante
idioms:
- iceberg lettuce tipo de alface (m)
- tip of the iceberg a ponta (f) do iceberg (m) (gír.)
idioms:
- iceberg lettuce разновидность салата, имеющего форму капусты
- tip of the iceberg верхушка айсберга
Español (Spanish)
n. - iceberg, témpano de hielo flotante
idioms:
- iceberg lettuce lechuga repollo
- tip of the iceberg la punta del iceberg
Svenska (Swedish)
n. - isberg, isbit (bildl.), känslokall person
中文（简体）(Chinese (Simplified))
冰山, 冷冰冰的人
idioms:
- iceberg lettuce 卷心莴苣
- tip of the iceberg 事物的表面小部分, 端倪
中文（繁體）(Chinese (Traditional))
n. - 冰山, 冷冰冰的人
idioms:
- iceberg lettuce 卷心萵苣
- tip of the iceberg 事物的表面小部分, 端倪
idioms:
- iceberg lettuce アイスバーグレタス
العربيه (Arabic)
(الاسم) جبل جليدي
עברית (Hebrew)
n. - קרחון, אדם קר-מזג
If you are unable to view some languages clearly, click here.
Post a question - any question - to the WikiAnswers community:
Copyrights:
American Heritage Dictionary
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
Read more
Britannica Concise Encyclopedia
Britannica Concise Encyclopedia. © 1994-2012 Encyclopædia Britannica, Inc. All rights reserved. Read more
McGraw-Hill Science & Technology Encyclopedia
McGraw-Hill Encyclopedia of Science and Technology. Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved.
Read more
Oxford Dictionary of Geography
A Dictionary of Geography. Copyright © Susan Mayhew 1992, 1997, 2004. All rights reserved.
Read more
Columbia Encyclopedia
The Columbia Electronic Encyclopedia, Sixth Edition Copyright © 2012, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/.
Read more
Word Tutor
Copyright © 2004-present by eSpindle Learning, a 501(c) nonprofit organization. All rights reserved.
eSpindle provides personalized spelling and vocabulary tutoring online; sign up free. Read more
eSpindle provides personalized spelling and vocabulary tutoring online; sign up free. Read more
Dictionary of Cultural Literacy: Science
The New Dictionary of Cultural Literacy, Third Edition Edited by E.D. Hirsch, Jr., Joseph F. Kett, and James Trefil. Copyright © 2002 by Houghton Mifflin Company. Published by Houghton Mifflin. All rights reserved.
Read more
Random House Word Menu
© 2010 Write Brothers Inc. Word Menu is a registered trademark of the Estate of Stephen Glazier.
Write Brothers Inc.
All rights reserved.
Read more
Bradford's Crossword Solver's Dictionary
Collins Bradford's Crossword Solver's Dictionary © Anne Bradford, 1986, 1993, 1997, 2000, 2003, 2005, 2008
HarperCollins Publishers
All rights reserved.
Read more
Wikipedia on Answers.com
This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article Iceberg.
Read more
