Changes

==Origin==

==Origin==

probably part [[translation]] of Dan or Norwegian ''isberg'', from is ''ice'' + ''berg'' [[mountain]]

probably part [[translation]] of Dan or Norwegian ''isberg'', from is ''ice'' + ''berg'' [[mountain]]

*[http://en.wikipedia.org/wiki/19th_century 1820]

*[https://en.wikipedia.org/wiki/19th_century 1820]

==Definitions==

==Definitions==

*1:  a large floating mass of ice detached from a [[glacier]]

*1:  a large floating mass of ice detached from a [[glacier]]

==Description==

==Description==

An '''iceberg''' is a large piece of freshwater ice that has broken off a [[glacier]] or an ice shelf and is floating freely in open [[water]]. It may subsequently become frozen into pack ice (one form of [http://en.wikipedia.org/wiki/Sea_ice sea ice]). As it drifts into shallower waters, it may come into contact with the seabed, a [[process]] referred to as [http://en.wikipedia.org/wiki/Seabed_gouging_by_ice seabed gouging by ice].

An '''iceberg''' is a large piece of freshwater ice that has broken off a [[glacier]] or an ice shelf and is floating freely in open [[water]]. It may subsequently become frozen into pack ice (one form of [https://en.wikipedia.org/wiki/Sea_ice sea ice]). As it drifts into shallower waters, it may come into contact with the seabed, a [[process]] referred to as [https://en.wikipedia.org/wiki/Seabed_gouging_by_ice seabed gouging by ice].

Because the [[density]] of pure ice is about 920 kg/m³, and that of [http://en.wikipedia.org/wiki/Sea_water sea water] about 1025 kg/m³, typically only one-tenth 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.

Because the [[density]] of pure ice is about 920 kg/m³, and that of [https://en.wikipedia.org/wiki/Sea_water sea water] about 1025 kg/m³, typically only one-tenth 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 246.1 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 [http://en.wikipedia.org/wiki/North_Atlantic 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-story building. These icebergs originate from the glaciers of western [http://en.wikipedia.org/wiki/Greenland Greenland] and may have an interior temperature of −15 to −20 °C (5 to −4 °F).[4]

Icebergs generally range from 1 to 75 metres (3.3 to 246.1 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 [https://en.wikipedia.org/wiki/North_Atlantic 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-story building. These icebergs originate from the glaciers of western [https://en.wikipedia.org/wiki/Greenland 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 [http://en.wikipedia.org/wiki/Ross_Ice_Shelf Ross Ice Shelf of Antarctica]. [http://en.wikipedia.org/wiki/Iceberg_B-15 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 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 [http://en.wikipedia.org/wiki/Scott_Island Scott Island], in the South Pacific Ocean, by the USS Glacier on November 12, 1956. This iceberg was larger than Belgium.

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 [https://en.wikipedia.org/wiki/Ross_Ice_Shelf Ross Ice Shelf of Antarctica]. [https://en.wikipedia.org/wiki/Iceberg_B-15 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 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 [https://en.wikipedia.org/wiki/Scott_Island Scott Island], in the South Pacific Ocean, by the USS Glacier on November 12, 1956. This iceberg was larger than Belgium.

When a piece of iceberg ice melts, it makes a fizzing sound called "Bergie Seltzer". This sound is made when the water-ice [[interface]] reaches compressed air bubbles trapped in the ice. As this happens, each bubble bursts, making a 'popping' sound. The bubbles contain air trapped in snow layers very early in the history of the ice, that [[eventually]] got buried to a given depth (up to several kilometers) and pressurized as it transformed into [http://en.wikipedia.org/wiki/Firn firn] then to glacial ice.

When a piece of iceberg ice melts, it makes a fizzing sound called "Bergie Seltzer". This sound is made when the water-ice [[interface]] reaches compressed air bubbles trapped in the ice. As this happens, each bubble bursts, making a 'popping' sound. The bubbles contain air trapped in snow layers very early in the history of the ice, that [[eventually]] got buried to a given depth (up to several kilometers) and pressurized as it transformed into [https://en.wikipedia.org/wiki/Firn firn] then to glacial ice.

[[Category: Earth Science]]

[[Category: Earth Science]]