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53-702: In spring and early summer, the Labrador Current transports icebergs from the glaciers of Greenland southwards into the trans-Atlantic shipping lanes. The waters of the current have a cooling effect on the Canadian Atlantic provinces , and on the United States' upper northeast coast from Maine south to Massachusetts . South of Cape Cod , Massachusetts, the Gulf Stream becomes the dominant ocean current. The Labrador Current has

106-533: A German liner, rammed an iceberg and suffered a crushed bow, but she was still able to complete her voyage. The advent of watertight compartmentalization in ship construction led designers to declare their ships "unsinkable". During the 1912 sinking of the Titanic , the iceberg that sank the Titanic killed more than 1,500 of its estimated 2,224 passengers and crew, seriously damaging the 'unsinkable' claim. For

159-430: A fizzing sound that some may call "Bergie Seltzer ". This sound results when the water-ice interface reaches compressed air bubbles trapped in the ice. As each bubble bursts it makes a "popping" sound and the acoustic properties of these bubbles can be used to study iceberg melt. An iceberg may flip, or capsize, as it melts and breaks apart, changing the center of gravity . Capsizing can occur shortly after calving when

212-635: A tendency to sometimes go farther south and/or east than normal. This can produce hazardous shipping conditions, for it can carry icebergs into an area of the Atlantic where they are not usually found. The current has been known to transport icebergs as far south as Bermuda and as far east as the Azores . After the sinking of the Titanic in 1912, the International Ice Patrol was set up to track icebergs, including those found in areas of

265-578: Is currently grounded off the coast of Antarctica in the western sector of the Amery region. In the last weeks of March 2000, Iceberg B-15 calved from the Ross Ice Shelf near Roosevelt Island , Antarctica. The calving occurred along pre-existing cracks in the ice shelf. The iceberg measured around 295 km × 37 km (159 nmi × 20 nmi), with a surface area of 10,915 km (3,182 sq nmi). Scientists believe that

318-464: Is made from icebergs found around St. John's, Newfoundland . Although annual iceberg supply in Newfoundland and Labrador exceeds the total freshwater consumption of the United States, in 2016 the province introduced a tax on iceberg harvesting and imposed a limit on how much fresh water can be exported yearly. The freshwater injected into the ocean by melting icebergs can change the density of

371-490: Is the iceberg that sank the Titanic . The catastrophe led to the establishment of an International Ice Patrol shortly after. Icebergs in both the northern and southern hemispheres have often been compared in size to multiples of the 59.1 square kilometres (22.8 sq mi)-area of Manhattan Island . Artists have used icebergs as the subject matter for their paintings. Frederic Edwin Church , The Icebergs , 1861

424-569: The Amundsen-Scott South Pole Station and broke into several smaller pieces, the largest of which was still named B-15A (now measuring approximately 1,700 km or 500 sq nmi). Three additional pieces were named B-15P, B-15M, and B-15N. Iceberg B-15A then moved farther up north and broke up into more pieces. These were spotted by air force fisheries patrol on 3 November 2006. On 21 November 2006 several large pieces were seen just 60 km (30 nmi) off

477-490: The Grand Banks of Newfoundland and provided the "limits of all known ice" in that vicinity to the maritime community. The IIP published their first records in 1921, which allowed for a year-by-year comparison of iceberg movement. 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

530-480: The Ross Ice Shelf of Antarctica . Icebergs may reach a height of more than 100 metres (300 ft) above the sea surface and have mass ranging from about 100,000 tonnes up to more than 10 million tonnes. Icebergs or pieces of floating ice smaller than 5 meters above the sea surface are classified as "bergy bits"; smaller than 1 meter—"growlers". The largest known iceberg in the North Atlantic

583-699: The Ross Sea and headed north, eventually breaking up into several smaller icebergs in October 2005. In 2018, a large piece of the original iceberg was steadily moving northward, located between the Falkland Islands and South Georgia Island . As of August 2023, the U.S. National Ice Center (USNIC) still lists one extant piece of B-15 that meets the minimum threshold for tracking (70 km or 20 sq nmi). This iceberg, B-15AB, measures 20 km × 7 km (11 nmi × 4 nmi); it

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636-558: The synthetic aperture radar (SAR) on the Sentinel-1 satellites . In Labrador and Newfoundland, iceberg management plans have been developed to protect offshore installations from impacts with icebergs. The idea of towing large icebergs to other regions as a source of water has been raised since at least the 1950s, without having been put into practice. In 2017, a business from the UAE announced plans to tow an iceberg from Antarctica to

689-587: 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 scientific and commercial purposes. This system

742-461: 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: The Danish Meteorological Institute monitors iceberg populations around Greenland using data collected by

795-513: The Gulf of Alaska generated a trans-Pacific Ocean swell that may have contributed to breaking B15-A into many pieces on 27 October 2005. The swell travelled 13,500 km (7,300 nmi) from Alaska to Antarctica over six days. Scientists are studying this event as an example of how weather in one area can have effects in other parts of the world, and with concern over the effects on global warming . A more detailed study in 2010, however, shows that

848-834: The Hudson Bay System, which is connected to the Labrador Sea, and contributes 50% of the freshwater transport of the Labrador Current. Hudson Bay is covered in ice in the winter and is ice-free in the summer. Hudson Bay has 42 rivers, contributing to the river runoff. The Labrador Current is made up of the Hudson Strait outflow, or the southeast flow, that meets with the Davis Strait and the West Greenland Current . This current then flows south, down through Newfoundland and Flemish Cap and along

901-480: The Middle East; in 2019 salvage engineer Nick Sloane announced a plan to move one to South Africa at an estimated cost of $ 200 million. In 2019, a German company, Polewater, announced plans to tow Antarctic icebergs to places like South Africa. Companies have used iceberg water in products such as bottled water , fizzy ice cubes and alcoholic drinks. For example, Iceberg Beer by Quidi Vidi Brewing Company

954-548: The Ross Sea. In December 2003, a small knife-shaped iceberg, B-15K (about 300 km ), detached itself from the main body of B-15A and started drifting northward. By January 2005, prevailing currents caused B-15A to drift toward the Drygalski Ice Tongue , a 70-kilometre-long (40 nmi) extension of the land-based David Glacier , which flows through the coastal mountains of Victoria Land. A few kilometres from

1007-572: The amount of freshwater that is imported from the North. The second part of the Labrador Current is deeper and is barotropic, meaning the density is only dependent on pressure, and reaches a depth of about 2500 meters. Baffin Bay and the Hudson Strait are the largest freshwater contributors to the Labrador Current. The Hudson Strait is a narrow channel that is about 400 km long and is the opening to

1060-412: The annual resupply ships to three research stations. The floe was expected to cause a catastrophic decline in the population of Adélie penguins , as it added considerable distances which parent penguins must travel back from the sea to their chicks. Weddell seals and skuas are also inhabitants of McMurdo Sound and their populations may have been affected as well. On 21 October 2005 a large storm in

1113-451: The basis of his paintings of arctic scenes with colossal icebergs made in the studio. American poet, Lydia Sigourney , wrote the poem "Icebergs" . While on a return journey from Europe in 1841, her steamship encountered a field of icebergs overnight, during an Aurora Borealis . The ship made it through unscathed to the next morning, when the sun rose and "touched the crowns, Of all those arctic kings." Iceberg B-15 Iceberg B-15

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1166-474: 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: Prior to 1914 there was no system in place to track icebergs to guard ships against collisions despite fatal sinkings of ships by icebergs. In 1907, SS Kronprinz Wilhelm ,

1219-470: The coast of Timaru , New Zealand—the largest measured about 1.8 km (1 nmi), rising 37 m (120 ft) from the surface of the ocean. As of 2018, four pieces remain that are large enough to be tracked by the National Ice Center (at least 70 km or 20 sq nmi). One piece, B-15Z, measures 19 km × 9 km (10 nmi × 5 nmi). It was located in

1272-670: The coast of Antarctica south of Africa. In 2021, B-15ab became the last fragment to remain on the US National Ice Center list of tracked icebergs, still grounded off the coast of Antarctica. On 29 January 2001, researchers from the University of Chicago and the University of Wisconsin installed weather and Global Positioning System instruments on Iceberg B-15A. It was the first time an iceberg had been monitored in this way. The data gathered led to an unprecedented understanding of how giant icebergs make their way through

1325-670: The continental shelf break. Part of this current moves westward along the continental slope near Nova Scotia, eventually reaching north of the Gulf Stream , this is called the Slope Water Current . The southward flow joins in the subpolar circulation, forming the narrow, western subpolar gyre in the North Atlantic. The current interacts with the Gulf Stream and the North Atlantic Current forming

1378-483: The drift velocity, and the variables f , k , and F correspond to the Coriolis force , the vertical unit vector, and a given force. The subscripts a, w, r, s, and p correspond to the air drag, water drag, wave radiation force, sea ice drag, and the horizontal pressure gradient force. Icebergs deteriorate through melting and fracturing, which changes the mass m , as well as the surface area, volume, and stability of

1431-637: 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, ice-breaking 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

1484-401: The enormous piece of ice broke away as part of a long-term natural cycle, which occurs every fifty to one hundred years. In 2000, 2002, and 2003, Iceberg B-15 broke up into several pieces, the largest of which, B-15A, covered 6,400 km (1,900 sq nmi) of the sea surface. In November 2003, after the separation from B-15J, B-15A drifted away from Ross Island on the open waters of

1537-487: The ice can create diverse colors. Sediment can create the dirty black coloration present in some icebergs. In addition to size classification (Table 1), icebergs can be classified on the basis of their shapes. 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. This type of iceberg, also known as an ice island , can be quite large, as in

1590-530: The ice tongue, the iceberg became stranded on a shallow seamount before resuming its northward course. On 10 April 2005, B-15A collided with the ice tongue, breaking off the tip of the ice tongue; the iceberg seemed unaffected by the collision. Iceberg B-15A continued to drift along the coast leaving McMurdo Sound . On 27–28 October 2005, the iceberg ran aground off Cape Adare in Victoria Land , generating seismic signals that were detected as far away as

1643-540: The iceberg " to illustrate a small part of a larger unseen issue. Icebergs are considered a serious maritime hazard . Icebergs vary considerably in size and shape. Icebergs that calve from glaciers in Greenland are often irregularly shaped while Antarctic ice shelves often produce large tabular (table top) icebergs. The largest iceberg in recent history, named B-15 , was measured at nearly 300 by 40 kilometres (186 by 25 mi) in 2000. The largest iceberg on record

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1696-653: The iceberg and the ocean, T 0 − T {\displaystyle T_{0}-T} is the temperature difference between the ocean and the iceberg, and L {\displaystyle L} is the length of the iceberg. K {\displaystyle K} is a constant based on properties of the iceberg and the ocean and is approximately 0.75 ∘ C − 1 m 0.4 day − 1 s 0.8 {\displaystyle 0.75^{\circ }{\text{C}}^{-1}{\text{m}}^{0.4}{\text{day}}^{-1}{\text{s}}^{0.8}} in

1749-518: The iceberg is young and establishing balance. Icebergs are unpredictable and can capsize anytime and without warning. Large icebergs that break off from a glacier front and flip onto the glacier face can push the entire glacier backwards momentarily, producing 'glacial earthquakes' that generate as much energy as an atomic bomb. Icebergs are generally white because they are covered in snow, but can be green, blue, yellow, black, striped, or even rainbow -colored. Seawater, algae and lack of air bubbles in

1802-541: The iceberg. Iceberg deterioration and drift, therefore, are interconnected ie. iceberg thermodynamics, and fracturing must be considered when modelling iceberg drift. Winds and currents may move icebergs close to coastlines, where they can become frozen into pack ice (one form of sea ice ), or drift into shallow waters, where they can come into contact with the seabed, a phenomenon called seabed gouging . Icebergs lose mass due to melting, and calving . Melting can be due to solar radiation, or heat and salt transport from

1855-643: The iron contained in sediments, can fuel blooms of phytoplankton. Samples collected from icebergs in Antarctica, Patagonia, Greenland, Svalbard, and Iceland, however, show that iron concentrations vary significantly, complicating efforts to generalize the impacts of icebergs on marine ecosystems. 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),

1908-646: The ocean where they are rarely located. The Labrador Current has an average annual velocity of 20 cm/s and is formed from very cold water that is around 1.5˚C from the Arctic through Baffin Island, Canada, and Western Greenland . These waters come together in the Labrador Sea . The Labrador Sea is affected by seasonality and will experience greater freshwater imports during the late spring and early summer with riverine runoff and glacial melt. The ocean circulation in

1961-399: The ocean. Iceberg calving is generally enhanced by waves impacting the iceberg. Melting tends to be driven by the ocean, rather than solar radiation. Ocean driven melting is often modelled as where M b {\displaystyle M_{\text{b}}} is the melt rate in m/day, Δ u {\displaystyle \Delta u} is the relative velocity between

2014-622: The polar ocean. The influence of the shape of an iceberg and of the Coriolis force on iceberg melting rates has been demonstrated in laboratory experiments. Wave erosion is more poorly constrained but can be estimated by where M e {\displaystyle M_{\text{e}}} is the wave erosion rate in m/day, c = 1 12 m day − 1 {\displaystyle c={\frac {1}{12}}{\text{m day}}^{-1}} , S S {\displaystyle S_{\text{S}}} describes

2067-858: The remainder of the ice season of that year, the United States Navy patrolled the waters and monitored ice movements. 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 to measure currents, ice-flow, ocean temperature , and salinity levels. They monitored iceberg dangers near

2120-442: The same orbit path as RADARSAT-1. Iceberg concentrations and size distributions 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

2173-430: The sea state, T S {\displaystyle T_{\text{S}}} is the sea surface temperature, and I c {\displaystyle I_{\text{c}}} is the sea ice concentration. Air trapped in snow forms bubbles as the snow is compressed to form firn and then glacial ice. Icebergs can contain up to 10% air bubbles by volume. These bubbles are released during melting, producing

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2226-426: The seawater in the vicinity of the iceberg. Fresh melt water released at depth is lighter, and therefore more buoyant, than the surrounding seawater causing it to rise towards the surface. Icebergs can also act as floating breakwaters , impacting ocean waves. Icebergs contain variable concentrations of nutrients and minerals that are released into the ocean during melting. Iceberg-derived nutrients, particularly

2279-429: The southern Atlantic Ocean, about 280 km (150 nmi) northwest of South Georgia Island . As it continues its move northward, the speed of melt increases. Most icebergs do not last long this far north. By 2020, only two pieces remained large enough to track. B-15aa – a direct remnant of B-15z – was drifting to the east of the island of South Georgia, in the south Atlantic Ocean. B-15ab remained among sea ice along

2332-417: The subpolar regions in the North Atlantic have seasonal variations due to the cold, freshwater Labrador Current and the warm, salty North Atlantic Current , as well as with changing surface winds, heat flux, and ice melting and formation. There are two parts that make up the Labrador Current. The first part is baroclinic, meaning that the density depends on temperature and pressure, and is buoyancy-driven due to

2385-427: The volume of an iceberg is above water, which follows from Archimedes's Principle of buoyancy ; the density of pure ice is about 920  kg/m (57 lb/cu ft), and that of seawater about 1,025 kg/m (64 lb/cu ft). The contour of the underwater portion can be difficult to judge by looking at the portion above the surface. The largest icebergs recorded have been calved , or broken off, from

2438-462: The waters of Antarctica and beyond. Iceberg B-15A collided with Drygalski Ice Tongue on 10 April 2005, breaking off an eight-square-kilometre ( 2 + 1 ⁄ 4  sq nmi) section of the ice tongue. Antarctic maps needed to be redrawn. B-15A prevented ocean currents and winds from assisting in the 2004–2005 summer break-up of the sea ice in McMurdo Sound , and was an obstacle to

2491-422: The western boundary current that makes up this gyre. Iceberg An iceberg is a piece of freshwater ice more than 15 meters (16 yards) long that has broken off a glacier or an ice shelf and is floating freely in open water. Smaller chunks of floating glacially derived ice are called "growlers" or "bergy bits". Much of an iceberg is below the water's surface, which led to the expression " tip of

2544-465: Was 168 metres (551 ft) above sea level, reported by the USCG icebreaker Eastwind in 1958, making it the height of a 55-story building. These icebergs originate from the glaciers of western Greenland and may have interior temperatures of −15 to −20 °C (5 to −4 °F). A given iceberg's trajectory through the ocean can be modelled by integrating the equation where m is the iceberg mass, v

2597-700: Was an Antarctic tabular iceberg measuring 335 by 97 kilometres (208 by 60 mi) sighted 240 kilometres (150 mi) west of Scott Island , in the South Pacific Ocean, by the USS Glacier on November 12, 1956. This iceberg was larger than Belgium . The word iceberg is a partial loan translation from the Dutch word ijsberg , literally meaning ice mountain , cognate to Danish isbjerg , German Eisberg , Low Saxon Iesbarg and Swedish isberg . Typically about one-tenth of

2650-450: Was painted from sketches Church completed on a boat trip off Newfoundland and Labrador. Caspar David Friedrich , The Sea of Ice , 1823–1824 is polar landscape with an iceberg and ship wreck depicting the dangers of such conditions . William Bradford created detailed paintings of sailing ships set in arctic coasts and was fascinated by icebergs. Albert Bierstadt made studies on arctic trips aboard steamships in 1883 and 1884 that were

2703-419: Was still the largest iceberg on Earth until it ran aground and split into several pieces October 27, 2005, an event that was observed by seismographs both on the iceberg and across Antarctica. It has been hypothesized that this breakup may also have been abetted by ocean swell generated by an Alaskan storm 6 days earlier and 13,500 kilometres (8,400 mi) away. One of the most infamous icebergs in history

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2756-494: Was the largest recorded iceberg by area . It measured around 295 by 37 kilometres (159 by 20 nautical miles), with a surface area of 11,000 square kilometres (3,200 square nautical miles), about the size of the island of Jamaica . Calved from the Ross Ice Shelf of Antarctica in March 2000, Iceberg B-15 broke up into smaller icebergs, the largest of which was named Iceberg B-15-A. In 2003, B-15A drifted away from Ross Island into

2809-578: 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) 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 2007, which uses SAR and multi-polarization modes and follows

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