Gulf Stream

The Gulf Stream, together with its northern extension the North Atlantic Drift, is a warm and swift Atlantic ocean current that originates in the Gulf of Mexico and stretches to the tip of Florida, and follows the eastern coastlines of the United States and Newfoundland before crossing the Atlantic Ocean. The process of western intensification causes the Gulf Stream to be a northward accelerating current off the east coast of North America. At about 40°0′N 30°0′W / 40.000°N 30.000°W, it splits in two, with the northern stream, the North Atlantic Drift, crossing to Northern Europe and the southern stream, the Canary Current, recirculating off West Africa.

The Gulf Stream influences the climate of the east coast of North America from Florida to Newfoundland, and the west coast of Europe. Although there has been recent debate, there is consensus that the climate of Western Europe and Northern Europe is warmer than it would otherwise be due to the North Atlantic drift which is the northeastern section of the Gulf Stream. It is part of the North Atlantic Gyre. Its presence has led to the development of strong cyclones of all types, both within the atmosphere and within the ocean. The Gulf Stream is also a significant potential source of renewable power generation. The Gulf Stream may be slowing down as a result of climate change.

The Gulf Stream is typically 100 kilometres (62 mi) wide and 800 metres (2,600 ft) to 1,200 metres (3,900 ft) deep. The current velocity is fastest near the surface, with the maximum speed typically about 2.5 metres per second (9 kph; 5.6 mph).

Golfstrom
Surface temperatures in the western North Atlantic. The North American landmass is black and dark blue (cold), while the Gulf Stream is red (warm). Source: NASA

History

Franklingulfstream
Benjamin Franklin's chart of the Gulf Stream published in Philadelphia in 1786

European discovery of the Gulf Stream dates to the 1512 expedition of Juan Ponce de León, after which it became widely used by Spanish ships sailing from the Caribbean to Spain.[1] A summary of Ponce de León's voyage log, on April 22, 1513, noted, "A current such that, although they had great wind, they could not proceed forward, but backward and it seems that they were proceeding well; at the end it was known that the current was more powerful than the wind."[2] Its existence was also known to Peter Martyr d'Anghiera.

Benjamin Franklin became interested in the North Atlantic Ocean circulation patterns. In 1768, while in England, Franklin heard a curious complaint from the Colonial Board of Customs: Why did it take British packets several weeks longer to reach New York from England than it took an average American merchant ship to reach Newport, Rhode Island, despite the merchant ships leaving from London and having to sail down the River Thames and then the length of the English Channel before they sailed across the Atlantic, while the packets left from Falmouth in Cornwall?[3]

Franklin asked Timothy Folger, his cousin twice removed (Nantucket Historical Society), a Nantucket Island whaling captain, for an answer. Folger explained that merchant ships routinely crossed the then-unnamed Gulf Stream—identifying it by whale behavior, measurement of the water's temperature, and changes in the water's color—while the mail packet captains ran against it.[3] Franklin had Folger sketch the path of the Gulf Stream on an old chart of the Atlantic and add written notes on how to avoid the Stream when sailing from England to America. Franklin then forwarded the chart to Anthony Todd, secretary of the British Post Office.[3] Franklin's Gulf Stream chart was printed in 1769 in London, but it was mostly ignored by British sea captains.[4] A copy of the chart was printed in Paris circa 1770–1773, and a third version was published by Franklin in Philadelphia in 1786.[5][6] The inset in the upper left part of the 1786 chart is an illustration of the migration pattern of herring and not an ocean current.

Properties

The Gulf Stream proper is a western-intensified current, driven largely by wind stress.[7] The North Atlantic Drift, in contrast, is largely thermohaline circulation–driven. In 1958 the oceanographer Henry Stommel noted that "very little water from the Gulf of Mexico is actually in the Stream".[8] By carrying warm water northeast across the Atlantic, it makes Western and especially Northern Europe warmer than it otherwise would be.[9]

Formation and behavior

Golfstream
Evolution of the Gulf Stream to the west of Ireland continuing as the North Atlantic Current

A river of sea water, called the Atlantic North Equatorial Current, flows westward off the coast of Central Africa. When this current interacts with the northeastern coast of South America, the current forks into two branches. One passes into the Caribbean Sea, while a second, the Antilles Current, flows north and east of the West Indies.[10] These two branches rejoin north of the Straits of Florida.

The trade winds blow westward in the tropics,[11] and the westerlies blow eastward at mid-latitudes.[12] This wind pattern applies a stress to the subtropical ocean surface with negative curl across the north Atlantic Ocean.[13] The resulting Sverdrup transport is equatorward.[14]

Because of conservation of potential vorticity caused by the northward-moving winds on the subtropical ridge's western periphery and the increased relative vorticity of northward moving water, transport is balanced by a narrow, accelerating poleward current. This flows along the western boundary of the ocean basin, outweighing the effects of friction with the western boundary current, and is known as the Labrador current.[15] The conservation of potential vorticity also causes bends along the Gulf Stream, which occasionally break off due to a shift in the Gulf Stream's position, forming separate warm and cold eddies.[16] This overall process, known as western intensification, causes currents on the western boundary of an ocean basin, such as the Gulf Stream, to be stronger than those on the eastern boundary.[17]

As a consequence, the resulting Gulf Stream is a strong ocean current. It transports water at a rate of 30 million cubic meters per second (30 sverdrups) through the Florida Straits. As it passes south of Newfoundland, this rate increases to 150 million cubic metres per second.[18] The volume of the Gulf Stream dwarfs all rivers that empty into the Atlantic combined, which barely total 0.6 million cubic metres per second. It is weaker, however, than the Antarctic Circumpolar Current.[19] Given the strength and proximity of the Gulf Stream, beaches along the East Coast of the United States may be more vulnerable to large sea-level anomalies, which significantly impact rates of coastal erosion.[20]

The Gulf Stream is typically 100 kilometres (62 mi) wide and 800 metres (2,600 ft) to 1,200 metres (3,900 ft) deep. The current velocity is fastest near the surface, with the maximum speed typically about 2.5 metres per second (5.6 mph).[21] As it travels north, the warm water transported by the Gulf Stream undergoes evaporative cooling. The cooling is wind-driven: Wind moving over the water causes evaporation, cooling the water and increasing its salinity and density. When sea ice forms, salts are left out of the ice, a process known as brine exclusion.[22] These two processes produce water that is denser and colder (or, more precisely, water that is still liquid at a lower temperature). In the North Atlantic Ocean, the water becomes so dense that it begins to sink down through less salty and less dense water. (The convective action is not unlike that of a lava lamp.) This downdraft of cold, dense water becomes a part of the North Atlantic Deep Water, a southgoing stream.[23] Very little seaweed lies within the current, although seaweed lies in clusters to its east.[24]

In April 2018, two studies published in Nature [25][26] found the Gulf Stream to be at its weakest for at least 1,600 years.[27]

Localized effects

The Gulf Stream is influential on the climate of the Florida peninsula. The portion off the Florida coast, referred to as the Florida current, maintains an average water temperature at or above 24 °C (75 °F) during the winter.[28] East winds moving over this warm water move warm air from over the Gulf Stream inland,[29] helping to keep temperatures milder across the state than elsewhere across the Southeast during the winter. Also, the Gulf Stream's proximity to Nantucket, Massachusetts adds to its biodiversity, as it is the northern limit for southern varieties of plant life, and the southern limit for northern plant species, Nantucket being warmer during winter than the mainland.[30]

The North Atlantic Current of the Gulf Stream, along with similar warm air currents, helps keep Ireland and the western coast of Great Britain a couple of degrees warmer than the east.[31] However, the difference is most dramatic in the western coastal islands of Scotland.[32] A noticeable effect of the Gulf Stream and the strong westerly winds (driven by the warm water of the Gulf Stream) on Europe occurs along the Norwegian coast.[9] Northern parts of Norway lie close to the Arctic zone, most of which is covered with ice and snow in winter. However, almost all of Norway's coast remains free of ice and snow throughout the year.[33] Weather systems warmed by the Gulf Stream drift into Northern Europe, also warming the climate behind the Scandinavian mountains.

Effect on cyclone formation

Sandy Oct 28 2012 1600Z
Hurricane Sandy intensifying along the axis of the Gulf Stream in 2012.

The warm water and temperature contrast along the edge of the Gulf Stream often increase the intensity of cyclones, tropical or otherwise. Tropical cyclone generation normally requires water temperatures in excess of 26.5 °C (79.7 °F).[34] Tropical cyclone formation is common over the Gulf Stream, especially in the month of July. Storms travel westward through the Caribbean and then either move in a northward direction and curve toward the eastern coast of the United States or stay on a north-westward track and enter the Gulf of Mexico.[35] Such storms have the potential to create strong winds and extensive damage to the United States' Southeast Coastal Areas. Hurricane Sandy in 2012 was a recent example of a hurricane passing over the Gulf Stream and gaining strength.[36]

Strong extratropical cyclones have been shown to deepen significantly along a shallow frontal zone, forced by the Gulf Stream itself, during the cold season.[37] Subtropical cyclones also tend to generate near the Gulf Stream. 75 percent of such systems documented between 1951 and 2000 formed near this warm water current, with two annual peaks of activity occurring during the months of May and October.[38] Cyclones within the ocean form under the Gulf Stream, extending as deep as 3,500 metres (11,500 ft) beneath the ocean's surface.[39]

Possible renewable power source

The theoretical maximum energy dissipation from the Gulf Stream by turbines is in the range of 20–60 GW.[40][41]

One suggestion, which could theoretically supply power comparable to several nuclear power plants, would deploy a field of underwater turbines placed 300 meters (980 ft) under the center of the core of the Gulf Stream.[42] Ocean thermal energy could also be harnessed to produce electricity using the temperature difference between cold deep water and warm surface water.[43]

See also

References

  1. ^ Fernandez-Armesto, Felipe (2006). Pathfinders: A Global History of Exploration. W. W. Norton & Company. p. 194. ISBN 978-0-393-06259-5.
  2. ^ Wilkinson, Jerry. "History of the Gulf Stream". Keys Historeum. Historical Preservation Society of the Upper Keys. Retrieved 15 July 2010.
  3. ^ a b c Tuchman, Barbara W. The First Salute: A View of the American Revolution New York: Ballantine Books, 1988. pp.221–222.
  4. ^ Isserman, Maurice (2002). "Ben Franklin and the Gulf Stream" (PDF). Study of place. TERC. Retrieved 15 July 2010.
  5. ^ Anon. "1785: Benjamin Franklin's 'Sundry Maritime Observations'". Ocean Explorer: Readings for ocean explorers. NOAA Office of Ocean Exploration and Research. Archived from the original on 18 December 2005. Retrieved 15 July 2010.
  6. ^ Richardson, Philip L.; Adams, Nathan T. (Spring 2018). "Uncharted Waters: Nantucket Whalers and the Franklin-Folger Chart of the Gulf Stream". Historic Nantucket. 68 (1): 17–24.
  7. ^ Wunsch, Carl (November 8, 2002). "What Is the Thermohaline Circulation?". Science. 298 (5596): 1179–1181. doi:10.1126/science.1079329. PMID 12424356. (see also Rahmstorf.)
  8. ^ Henry Stommel. (1958). The Gulf Stream: A Physical and Dynamical Description. Berkeley: University of California Press. p.22
  9. ^ a b Barbie Bischof; Arthur J. Mariano; Edward H. Ryan (2003). "The North Atlantic Drift Current". The National Oceanographic Partnership Program. Retrieved 2008-09-10.
  10. ^ Elizabeth Rowe; Arthur J. Mariano; Edward H. Ryan. "The Antilles Current". Cooperative Institute for Marine and Atmospheric Studies. Retrieved 2009-01-06.
  11. ^ Glossary of Meteorology (2009). "trade winds". Glossary of Meteorology. American Meteorological Society. Archived from the original on 2008-12-11. Retrieved 2008-09-08.
  12. ^ Glossary of Meteorology (2009). Westerlies. Archived 2010-06-22 at the Wayback Machine American Meteorological Society. Retrieved on 2009-04-15.
  13. ^ Matthias Tomczak and J. Stuart Godfrey (2001). Regional Oceanography: an Introduction. Matthias Tomczak, pp. 42. ISBN 81-7035-306-8. Retrieved on 2009-05-06.
  14. ^ Earthguide (2007). Lesson 6: Unraveling the Gulf Stream Puzzle - On a Warm Current Running North. University of California at San Diego. Retrieved on 2009-05-06.
  15. ^ Angela Colling (2001). Ocean Circulation. Butterworth-Heinemann. p. 96. ISBN 978-0-08-053794-8.
  16. ^ Maurice L. Schwartz (2006). Encyclopedia of Coastal Science. Springer Science & Business Media. p. 1037. Bibcode:2006ecs..book.....S. ISBN 978-1-4020-3880-8.
  17. ^ National Environmental Satellite, Data, and Information Service (2009). Investigating the Gulf Stream Archived 2010-05-03 at the Wayback Machine. North Carolina State University. Retrieved on 2009-05-06.
  18. ^ Joanna Gyory; Arthur J. Mariano; Edward H. Ryan. "The Gulf Stream". Cooperative Institute for Marine and Atmospheric Studies. Retrieved 2009-01-06.
  19. ^ Ryan Smith; Melicie Desflots; Sean White; Arthur J. Mariano; Edward H. Ryan. "The Antarctic CP Current". Cooperative Institute for Marine and Atmospheric Studies. Retrieved 2009-01-06.
  20. ^ Theuerkauf, Ethan J., et al. "Sea level anomalies exacerbate beach erosion". Geophysical Research Letters 41.14 (2014): 5139–5147.
  21. ^ Phillips, Pamela. "The Gulf Stream". USNA/Johns Hopkins. Retrieved 2007-08-02.
  22. ^ Russel, Randy. "Thermohaline Ocean Circulation". University Corporation for Atmospheric Research. Retrieved 2009-01-06.
  23. ^ Behl, R. "Atlantic Ocean water masses". California State University Long Beach. Archived from the original on May 23, 2008. Retrieved 2009-01-06.
  24. ^ Edward and George William Blunt (1857). The American Coast Pilot. Edward and George William Blunt. Retrieved 2009-01-06.
  25. ^ Thornalley, David J. R.; Oppo, Delia W.; Ortega, Pablo; Robson, Jon I.; Brierley, Chris M.; Davis, Renee; Hall, Ian R.; Moffa-Sanchez, Paola; Rose, Neil L.; Spooner, Peter T.; Yashayaev, Igor; Keigwin, Lloyd D. (11 April 2018). "Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years". Nature. 556 (7700): 227–230. Bibcode:2018Natur.556..227T. doi:10.1038/s41586-018-0007-4.
  26. ^ Caesar, L.; Rahmstorf, S.; Robinson, A.; Feulner, G.; Saba, V. (11 April 2018). "Observed fingerprint of a weakening Atlantic Ocean overturning circulation". Nature. 556 (7700): 191–196. Bibcode:2018Natur.556..191C. doi:10.1038/s41586-018-0006-5.
  27. ^ "Gulf Stream current at its weakest in 1,600 years, studies show". The Guardian. 12 April 2018. Retrieved 12 April 2018.
  28. ^ Geoff Samuels (2008). "Caribbean Mean SSTs and Winds". Cooperative Institute For Marine and Atmospheric Studies. Retrieved 2009-01-16.
  29. ^ National Climatic Data Center. Climatic Wind Data for the United States. Retrieved on 2007-06-02. Archived June 13, 2007, at the Wayback Machine
  30. ^ Sarah Oktay. "Description of Nantucket Island". University of Massachusetts Boston. Retrieved 2009-01-06.
  31. ^ Professor Hennessy (1858). Report of the Annual Meeting: On the Influence of the Gulf-stream on the Climate of Ireland. Richard Taylor and William Francis. Retrieved 2009-01-06.
  32. ^ "Satellites Record Weakening North Atlantic Current Impact". NASA. Retrieved 2008-09-10.
  33. ^ Erik A. Rasmussen; John Turner (2003). Polar Lows. Cambridge University Press. p. 68.
  34. ^ Atlantic Oceanographic and Meteorological Laboratory, Hurricane Research Division. "Frequently Asked Questions: How do tropical cyclones form?". NOAA. Retrieved 2006-07-26.
  35. ^ "Atlantic hurricane best track (HURDAT version 2)". Hurricane Research Division (Database). National Hurricane Center. May 1, 2018. Retrieved February 15, 2019.
  36. ^ The Making of a Superstorm
  37. ^ S. Businger, T. M. Graziano, M. L. Kaplan, and R. A. Rozumalski. Cold-air cyclogenesis along the Gulf-Stream front: investigation of diabatic impacts on cyclone development, frontal structure, and track. Retrieved on 2008-09-21.
  38. ^ David M. Roth. P 1.43 A FIFTY YEAR HISTORY OF SUBTROPICAL CYCLONES. American Meteorological Society. Retrieved on 2008-09-21.
  39. ^ D. K. Savidge and J. M. Bane. Cyclogenesis in the deep ocean beneath the Gulf Stream. 1. Description. Retrieved on 2008-09-21.
  40. ^ Yang, Xiufeng; Haas, Kevin A.; Fritz, Hermann M. (1 July 2013). "Theoretical Assessment of Ocean Current Energy Potential for the Gulf Stream System" (PDF). Marine Technology Society Journal. 47 (4): 101–112. doi:10.4031/MTSJ.47.4.3. Archived from the original (PDF) on 2019-02-03.
  41. ^ Ocean Current Energy Assessment for the Gulf Stream Xiufeng Yang*, Kevin A. Haas, Hermann M. Fritz [1] Retrieved 2014-05-26
  42. ^ The Institute for Environmental Research & Eductation. Tidal.pdf Archived 2010-10-11 at the Wayback Machine Retrieved on 2010-07-28.
  43. ^ Jeremy Elton Jacquot. Gulf Stream's Tidal Energy Could Provide Up to a Third of Florida's Power. Retrieved on 2008-09-21.

Further reading

External links

  • Ocean Motion—Description of the Gulf Stream as a western boundary current
Florida Current

The Florida Current is a thermal ocean current that flows from the Straits of Florida around the Florida Peninsula and along the southeastern coast of the United States before joining the Gulf Stream Current near Cape Hatteras. Its contributing currents are the Loop Current and the Antilles Current. The current was discovered by Spanish explorer Juan Ponce de León in 1513.

The Florida Current results from the movement of water pushed from the Atlantic into the Caribbean Sea by the rotation of the Earth (which exerts a greater force at the equator). The water piles up along Central America and flows northward through the Yucatán Channel into the Gulf of Mexico. The water is heated in the Gulf and forced out through the Florida Straits, between the Florida Keys and Cuba and flows northward along the east coast of the United States. The Florida Current is often referred to imprecisely as the Gulf Stream. In fact, the Florida Current joins the Gulf Stream off the east coast of Florida.

Gervais' beaked whale

Gervais' beaked whale (Mesoplodon europaeus), sometimes known as the Antillian beaked whale, Gulf Stream beaked whale, or European beaked whale (from which its scientific name is derived) is the most frequently stranding type of mesoplodont whale off the coast of North America. It has also stranded off South America and Africa.

Grumman Gulfstream II

The Gulfstream II (G-II) is an American twin engine business jet designed and built by Grumman and then in succession, Grumman American and finally Gulfstream American. Its Grumman model number is G-1159 and its US military designation is C-11 Gulfstream II. It has been succeeded by the Gulfstream III. The first Gulfstream II flew on October 2, 1966.

Gulf Stream, Florida

Gulf Stream is a town in Palm Beach County, Florida, United States. The population was 716 at the 2000 census. Gulf Stream ranked as the 11th highest-income place in the United States. As of 2004, the population recorded by the U.S. Census Bureau was 746.

Gulf Stream Council

Gulf Stream Council is a council of the Boy Scouts of America in southeast Florida with the headquarters in Palm Beach Gardens. Founded in 1914, the Gulf Stream Council serves Scouts in Palm Beach, Martin, St. Lucie, Indian River, Okeechobee, Glades and Hendry counties. Throughout its area, it serves over 24,000 youth.

Henry Stommel

Henry "Hank" Melson Stommel (September 27, 1920 – January 17, 1992) was a major contributor to the field of physical oceanography. Beginning in the 1940s, he advanced theories about global ocean circulation patterns and the behavior of the Gulf Stream that form the basis of physical oceanography today. Widely recognized as one of the most influential and productive oceanographers of his time, Stommel was both a groundbreaking theoretician and an astute, seagoing observer.

Isthmus of Panama

The Isthmus of Panama (Spanish: Istmo de Panamá), also historically known as the Isthmus of Darien (Istmo de Darién), is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North and South America. It contains the country of Panama and the Panama Canal. Like many isthmuses, it is a location of great strategic value.

The isthmus formed around 2.8 million years ago. This major geological event separated the Atlantic and Pacific Oceans and caused the creation of the Gulf Stream. This was first suggested in 1910 by North American paleontologist Henry Fairfield Osborn. He based the proposal on the fossil record of mammals in Central America. This conclusion provided a foundation for Alfred Wegener when he proposed the theory of continental drift in 1912.

Kuroshio Current

The Kuroshio (黒潮, , "くろしお", [kɯɾoɕio] "Black Tide", "Japan Current") is a north-flowing ocean current on the west side of the North Pacific Ocean. It is similar to the Gulf Stream in the North Atlantic and is part of the North Pacific ocean gyre. Like the Gulf stream, it is a strong western boundary current.

Marine current power

Marine current power is a form of marine energy obtained from harnessing of the kinetic energy of marine currents, such as the Gulf stream. Although not widely used at present, marine current power has an important potential for future electricity generation. Marine currents are more predictable than wind and solar power.A 2006 report from United States Department of the Interior estimates that capturing just 1/1,000th of the available energy from the Gulf Stream would supply Florida with 35% of its electrical needs.Strong ocean currents are generated from a combination of temperature, wind, salinity, bathymetry, and the rotation of the earth. The sun acts as the primary driving force, causing winds and temperature differences. Because there are only small fluctuations in current speed and stream location with minimal changes in direction, ocean currents may be suitable locations for deploying energy extraction devices such as turbines. Other effects such as regional differences in temperature and salinity and the Coriolis effect due to the rotation of the earth are also major influences. The kinetic energy of marine currents can be converted in much the same way that a wind turbine extracts energy from the wind, using various types of open-flow rotors.The potential of electric power generation from marine tidal currents is enormous. There are several factors that make electricity generation from marine currents very appealing when compared to other renewables:

The high load factors resulting from the fluid properties. The predictability of the resource, so that, unlike most of other renewables, the future availability of energy can be known and planned for.

The potentially large resource that can be exploited with little environmental impact, thereby offering one of the least damaging methods for large-scale electricity generation.

The feasibility of marine-current power installations to provide also base grid power, especially if two or more separate arrays with offset peak-flow periods are interconnected.

Nantucket Sound

Nantucket Sound is a roughly triangular area of the Atlantic Ocean offshore from the U.S. state of Massachusetts. It is 30 miles (48 km) long and 25 miles (40 km) wide, and is enclosed by Cape Cod on the north, Nantucket on the south, and Martha's Vineyard on the west. Between Cape Cod and Martha's Vineyard it is connected to the Vineyard Sound. Ports on Nantucket Sound include Nantucket and Hyannis, Massachusetts.

Nantucket Sound possesses significant marine habitat for a diversity of ecologically and economically important species. "The Sound" has particular significance for several federally protected species of wildlife and a variety of commercially and recreationally valuable fisheries.

The Sound is located at a confluence of the cold Labrador Currents and the warm Gulf Stream. This creates a unique coastal habitat representing the southern range for Northern Atlantic species and the northern range for Mid-Atlantic species. Nantucket Sound has much biological diversity and contains habitats that range from open sea to salt marshes, as well as warm-water beaches on the Cape and Islands coasts.

North Atlantic Current

The North Atlantic Current (NAC), also known as North Atlantic Drift and North Atlantic Sea Movement, is a powerful warm western boundary current within the Atlantic Ocean that extends the Gulf Stream northeastward.The NAC originates from where the Gulf Stream turns north at the Southeast Newfoundland Rise, a submarine ridge that stretches southeast from the Grand Banks. The NAC flows northward east of the Grand Banks, from 40°N to 51°N, before turning sharply east to cross the Atlantic. It transports more warm tropical water to northern latitudes than any other boundary current; more than 40 Sv in the south and 20 Sv as it crosses the Mid-Atlantic Ridge. It reaches speeds of 2 knots near the North American coast. Directed by topography, the NAC meanders heavily, but in contrast to the meanders of the Gulf Stream, the NAC meanders remain stable without breaking off into eddies.The colder parts of the Gulf Stream turn northward near the "tail" of the Grand Banks at 50°W where the Azores Current branches off to flow south of the Azores. From there the NAC flows northeastward, east of the Flemish Cap (47°N, 45°W). Approaching the Mid-Atlantic Ridge, it then turns eastward and becomes much broader and more diffuse. It then splits into a colder northeastern branch and a warmer eastern branch. As the warmer branch turns southward, most of the subtropical component of the Gulf Stream is diverted southward, and as a consequence, the North Atlantic is mostly supplied by subpolar waters, including a contribution from the Labrador Current recirculated into the NAC at 45°N.West of Continental Europe, it splits into two major branches. One branch goes southeast, becoming the Canary Current as it passes northwest Africa and turns southwest. The other major branch continues north along the coast of Northwestern Europe.

Other branches include the Irminger Current and the Norwegian Current. Driven by the global thermohaline circulation, the North Atlantic Current is part of the wind-driven Gulf Stream, which goes further east and north from the North American coast across the Atlantic and into the Arctic Ocean.

The North Atlantic Current, together with the Gulf Stream, have a long-lived reputation for having a considerable warming influence on European climate. However, the principal cause for differences in winter climate between North America and Europe seems to be winds rather than ocean currents (although the currents do exert influence at very high latitudes by preventing the formation of sea ice).

Ocean current

An ocean current is a continuous, directed movement of sea water generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences. Depth contours, shoreline configurations, and interactions with other currents influence a current's direction and strength. Ocean currents are primarily horizontal water movements.

Ocean currents flow for great distances, and together, create the global conveyor belt which plays a dominant role in determining the climate of many of the Earth’s regions. More specifically, ocean currents influence the temperature of the regions through which they travel. For example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them. Perhaps the most striking example is the Gulf Stream, which makes northwest Europe much more temperate than any other region at the same latitude. Another example is Lima, Peru, where the climate is cooler, being sub-tropical, than the tropical latitudes in which the area is located, due to the effect of the Humboldt Current.

Queen Victoria Sea

The Queen Victoria Sea (Russian: Море королевы Виктории, Morye Korolevy Viktorii) is a body of water in the Arctic Ocean, stretching from northeast of Svalbard to northwest Franz Josef Land. It is obstructed by ice most of the year.

This sea is named after Queen Victoria. Russian Arctic explorer Valentin Akkuratov claimed that a branch of the Gulf Stream reached as far north as the Queen Victoria Sea.

Robert Craft

Robert Lawson Craft (October 20, 1923 – November 10, 2015) was an American conductor and writer. He is best known for his intimate working friendship with Igor Stravinsky, on which Craft drew in producing numerous recordings and books.

Sebastián de Ocampo

Sebastián de Ocampo was a Spanish navigator and explorer. He is believed to have been the first navigator to have circumnavigated the island of Cuba in 1508.Under the authority of the Governor of Hispaniola, Ocampo sailed along the northern coast of the island through the Old Bahama Channel and around the western point, Cape San Antonio. The voyage took eight months, and was against the Gulf Stream. Europeans had already frequented Cuba by the time Ocampo embarked on his journey, but his circumnavigation confirmed that the area was indeed surrounded by water, and not a peninsula as was speculated. Ocampo returned to Hispaniola with news of the body of water that lay beyond. Before that, and after the Spanish discovery of the Antilles, several maps portrayed what latter-day interpreters have assumed to be the Gulf of Mexico, thereby disputing the actual discovery date. He died at an old age in a year no one is sure of.

Shutdown of thermohaline circulation

A shutdown or slowdown of the thermohaline circulation is an effect of global warming on a major ocean circulation.

Data from NASA in 2010 suggested that the Atlantic Meridional Overturning Circulation (AMOC) had not slowed down, but may have actually sped up slightly since 1993. A 2015 study suggested that the AMOC has weakened by 15-20% in 200 years.

The Gulf Stream (painting)

The Gulf Stream is an 1899 oil painting by Winslow Homer. It shows a man in a small dismasted rudderless fishing boat struggling against the waves of the sea, and was the artist's last statement on a theme that had interested him for more than a decade. Homer vacationed often in Florida, Cuba, and the Caribbean.

The Old Man and the Sea

The Old Man and the Sea is a short novel written by the American author Ernest Hemingway in 1951 in Cuba, and published in 1952. It was the last major work of fiction by Hemingway that was published during his lifetime. One of his most famous works, it tells the story of Santiago, an aging Cuban fisherman who struggles with a giant marlin far out in the Gulf Stream off the coast of Cuba.In 1953, The Old Man and the Sea was awarded the Pulitzer Prize for Fiction, and it was cited by the Nobel Committee as contributing to their awarding of the Nobel Prize in Literature to Hemingway in 1954.

Thermohaline circulation

Thermohaline circulation (THC) is a part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes. The adjective thermohaline derives from thermo- referring to temperature and -haline referring to salt content, factors which together determine the density of sea water. Wind-driven surface currents (such as the Gulf Stream) travel polewards from the equatorial Atlantic Ocean, cooling en route, and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of around 1000 years) upwell in the North Pacific. Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's oceans a global system. On their journey, the water masses transport both energy (in the form of heat) and mass of substances (solids, dissolved substances and gases) around the globe. As such, the state of the circulation has a large impact on the climate of the Earth.

The thermohaline circulation is sometimes called the ocean conveyor belt, the great ocean conveyor, or the global conveyor belt. On occasion, it is used to refer to the meridional overturning circulation (often abbreviated as MOC). The term MOC is more accurate and well defined, as it is difficult to separate the part of the circulation which is driven by temperature and salinity alone as opposed to other factors such as the wind and tidal forces. Moreover, temperature and salinity gradients can also lead to circulation effects that are not included in the MOC itself.

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