[35], There are five intermediate waters: four low-salinity waters formed at subpolar latitudes and one high-salinity formed through evaporation. Blue whiting reached a 2.4 million tons peak in 2004 but was down to 628,000 tons in 2013. The cold water currents contribute to heavy fog off the coast of eastern Canada (the Grand Banks of Newfoundland area) and Africa's north-western coast. The second-largest ocean on Earth, the Atlantic drives our weather patterns, including hurricanes, and is home to many species from sea turtles to dolphins. This group of people not only expanded over the whole of Africa, but also started to disperse out of Africa into Asia, Europe, and Australasia around 65,000 years ago and quickly replaced the archaic humans in these regions. Ocean currents influence the climate by transporting warm and cold waters to other regions. It also expanded the exploited areas from near-shore to the open sea and to great depths to include deep-water species such as redfish, Greenland halibut, witch flounder, and grenadiers. It covers approximately 20 percent of Earth's surface and about 29 percent of its water surface area. Average water temperatures in the Atlantic Ocean Arctic Tropics Temperate °C °F °C °F °C °F; January-1: 30.2: 27.4: 81.4: 13.2: 55.7: February-1.4: 29.5: 27.1: 80.8: 12.8: 55.1: March-1.6: 28: 27.1: 80.8: 12.7: 54.8: April-1.4: 29.5: 27.6: 81.6: 13.6: 56.5: May-1.4: 29.9: 28.1: 82.5: 15.3: 59.6: June-1.2: 29.8: 28.3: 83: 17.5: 63.5: July: 0.1: 32.3: 28.3: 83: 19.3: 66.7: August: 2.9: 37.3: 29: 84.2: 20.5: 68.9: September: … In contrast, 8–7 kya-old shell middens in Portugal, Denmark, and Brazil generated thousands of tons of debris and artefacts. 'Sea of Atlantis') and in The Histories of Herodotus around 450 BC (Hdt. Excluding its marginal seas, the Atlantic covers 81,760,000 km2 (31,570,000 sq mi) and has a volume of 305,811,900 km3 (73,368,200 cu mi). [32] The deep ocean floor is thought to be fairly flat with occasional deeps, abyssal plains, trenches, seamounts, basins, plateaus, canyons, and some guyots. Round sardinella was an important species in the 1990s but is now considered overfished. Between the 15th century and 1888, when Brazil became the last part of the Americas to end the slave trade, an estimated ten million Africans were exported as slaves, most of them destined for agricultural labour. Municipal pollution comes from the eastern United States, southern Brazil, and eastern Argentina; oil pollution in the Caribbean Sea, Gulf of Mexico, Lake Maracaibo, Mediterranean Sea, and North Sea; and industrial waste and municipal sewage pollution in the Baltic Sea, North Sea, and Mediterranean Sea. Besides major transatlantic transportation and communication routes, the Atlantic offers abundant petroleum deposits in the sedimentary rocks of the continental shelves. Iceland began to form 62 million years ago due to a particularly concentrated mantle plume. ", "Why doesn't the South Atlantic Ocean experience tropical cyclones? In latitudes above 40° North some east–west oscillation, known as the North Atlantic oscillation, occurs. Rifting in the central segment, however, coincided with the Cretaceous Normal Superchron (also known as the Cretaceous quiet period), a 40 Ma period without magnetic reversals, which makes it difficult to date sea-floor spreading in this segment. [84] In the western Atlantic carbonate platforms dominate large areas, for example, the Blake Plateau and Bermuda Rise. The eastern water is saltier because of its proximity to Mediterranean Water. 21st-century global warming will probably result in an equilibrium sea-level rise five times greater than today, whilst melting of glaciers, including that of the Greenland ice-sheet, expected to have virtually no effect during the 21st century, will probably result in a sea-level rise of 3–6 m over a millennium. [6], The Atlantic harbors petroleum and gas fields, fish, marine mammals (seals and whales), sand and gravel aggregates, placer deposits, polymetallic nodules, and precious stones. [6], The Coriolis effect circulates North Atlantic water in a clockwise direction, whereas South Atlantic water circulates counter-clockwise. Saison cyclonique dans l'océan Atlantique sud‎ – 1 C Pages dans la catégorie « Climat de l'océan Atlantique » Cette catégorie contient les 6 pages suivantes. The MSA population was small and dispersed and the rate of their reproduction and exploitation was less intense than those of later generations. The MAR reaches above 2,000 m (6,600 ft) along most of its length, but is interrupted by larger transform faults at two places: the Romanche Trench near the Equator and the Gibbs Fracture Zone at 53°N. Water Temperature Table of the Central Atlantic Coast (Google Maps-based Web page) The USS Stewart used a Navy Sonic Depth Finder to draw a continuous map across the bed of the Atlantic. Selon une étude publiée par l'Université de Londres, une augmentation de la température à la surface de l'océan de l'ordre de 0,5°C a élevé de 40% le nombre d'ouragans dans l'océan Atlantique entre 1996 et 2005. The NADW, in its turn, feeds the meridional overturning circulation (MOC), the northward heat transport of which is threatened by anthropogenic climate change. Off South Africa and Namibia deep-water hake and shallow-water Cape hake have recovered to sustainable levels since regulations were introduced in 2006 and the states of Southern African pilchard and anchovy have improved to fully fished in 2013. The biggest culprits are rivers and with them many agriculture fertilizer chemicals as well as livestock and human waste. In the middle latitudes, the area of maximum temperature variations, values may vary by 7–8 °C (13–14 °F). Drift net fishing can kill dolphins, albatrosses and other seabirds (petrels, auks), hastening the fish stock decline and contributing to international disputes. [57] The opening of the North Atlantic caused significant uplift of continental crust along the coast. Around 150 Ma sea-floor spreading propagated northward into the southern segment. (Complete List of Average Temperatures) Use the near real-time water temperature data with discretion, because they may contain errors. The opening of the Northern Atlantic closely followed the margins of its predecessor, the Iapetus Ocean, and spread from the Central Atlantic in six stages: Iberia–Newfoundland, Porcupine–North America, Eurasia–Greenland, Eurasia–North America. [88], Marine pollution is a generic term for the entry into the ocean of potentially hazardous chemicals or particles. [61], About 50 Ma the opening of the Drake Passage resulted from a change in the motions and separation rate of the South American and Antarctic plates. A peace treaty mediated by the Pope divided the conquered territories into Spanish and Portuguese sectors while keeping other colonial powers away. The wide range of salinities in the North Atlantic is caused by the asymmetry of the northern subtropical gyre and the large number of contributions from a wide range of sources: Labrador Sea, Norwegian-Greenland Sea, Mediterranean, and South Atlantic Intermediate Water. Due to a consistently strong wind shear and a weak Intertropical Convergence Zone, South Atlantic tropical cyclones are rare. [91], North Atlantic hurricane activity has increased over past decades because of increased sea surface temperature (SST) at tropical latitudes, changes that can be attributed to either the natural Atlantic Multidecadal Oscillation (AMO) or to anthropogenic climate change. [78] [12] During the Age of Discovery, the Atlantic was also known to English cartographers as the Great Western Ocean. The Laurentian Abyss is found off the eastern coast of Canada. Almost half of the stocks are fished at biologically unsustainable levels. [76] A proposed route across the Pacific to South America could explain early South American finds and another hypothesis proposes a northern path, through the Canadian Arctic and down the North American Atlantic coast. This heat uptake provides a time-lag for climate change but it also results in thermal expansion of the oceans which contributes to sea level rise. The Landnámabók (Book of Settlement) records disastrous famines during the first century of settlement — "men ate foxes and ravens" and "the old and helpless were killed and thrown over cliffs" — and by the early 1200s hay had to be abandoned for short-season crops such as barley. Sa surface, sans les mers bordières, est de l'ordre de 82 millions de ki Une équipe de chercheurs a récemment fourni la réponse grâce à l’analyse détaillée de sédiments lacustres. In the North-East Atlantic 21% of stocks are considered overfished. No later than 130 Ma rifting had reached the Walvis Ridge–Rio Grande Rise. The warmest Pornichet sea water temperatures in the middle of August require something like a … It runs from 87°N or 300 km (190 mi) south of the North Pole to the subantarctic Bouvet Island at 54°S. The third group, "continuously increasing trend since 1950", is only found in the Indian Ocean and Western Pacific. The apparent fit between the coastlines of the two continents was noted on the first maps that included the South Atlantic and it was also the subject of the first computer-assisted plate tectonic reconstructions in 1965. [66] As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). Currently, there is no cost-effective way to mine or extract gold from the ocean to make a profit. Avec une température largement sous les moyennes dans l'océan Pacifique equatorial, nous assistons depuis plusieurs mois à un phénomène dit "La Niña". [37], The clockwise warm-water North Atlantic Gyre occupies the northern Atlantic, and the counter-clockwise warm-water South Atlantic Gyre appears in the southern Atlantic. One from 62 to 58 million years ago predates the separation of Greenland from northern Europe while the second from 56 to 52 million years ago happened as the separation occurred. England, France, and the Dutch Republic enviously watched the Spanish and Portuguese wealth grow and allied themselves with pirates such as Henry Mainwaring and Alexandre Exquemelin. [42], The Sargasso Sea in the western North Atlantic can be defined as the area where two species of Sargassum (S. fluitans and natans) float, an area 4,000 km (2,500 mi) wide and encircled by the Gulf Stream, North Atlantic Drift, and North Equatorial Current. Because of the ocean's great capacity to store and release heat, maritime climates are more moderate and have less extreme seasonal variations than inland climates. The ice season is longer in the polar regions, but there is little shipping in those areas. Visualiser les conditions éoliennes, météorologiques, océanographiques et de pollution actuelles, telles que prévues par des superordinateurs, sur une carte animée interactive. Selon les chercheurs, ces résultats montrent que le réchauffement récent de la surface de l’océan Atlantique est sans précédent. Meteo Paris - … Some of these canyons extend along the continental rises and farther into the abyssal plains as deep-sea channels.[25]. The excess of oxygen-depleting chemicals leads to hypoxia and the creation of a dead zone. [6], Scientific explorations of the Atlantic include the Challenger expedition, the German Meteor expedition, Columbia University's Lamont-Doherty Earth Observatory and the United States Navy Hydrographic Office.[6]. [86], In the North-West Atlantic landings have decreased from 4.2 million tons in the early 1970s to 1.9 million tons in 2013. [6], The oceans are the major source of the atmospheric moisture that is obtained through evaporation. L'étude s'est concentrée sur 11 modèles informatiques qui reproduisaient le plus fidèlement les différentes strates de température de l'océan Atlantique nord. [9] In these uses, the name refers to Atlas, the Titan in Greek mythology, who supported the heavens and who later appeared as a frontispiece in Medieval maps and also lent his name to modern atlases. The most productive areas include the Grand Banks of Newfoundland, the Scotian Shelf, Georges Bank off Cape Cod, the Bahama Banks, the waters around Iceland, the Irish Sea, the Bay of Fundy, the Dogger Bank of the North Sea, and the Falkland Banks. Climatic zones vary with latitude; the warmest zones stretch across the Atlantic north of the equator. Geologists distinguish two magmatic phases. From the 1950s to the 1970s the introduction of European and Asian distant-water fleets in the area dramatically increased the fishing capacity and the number of exploited species. La figure 4.3 représente la distribution moyenne de la température sur une coupe de l'océan Atlantique Ouest.Cette figure illustre bien le confinement des températures élevées dans la partie supérieure de l'océan. The MAR is a barrier for bottom water, but at these two transform faults deep water currents can pass from one side to the other. [6] [6], From October to June the surface is usually covered with sea ice in the Labrador Sea, Denmark Strait, and Baltic Sea. Large variations in the subpolar gyre on a decade-century scale, associated with the North Atlantic oscillation, are especially pronounced in Labrador Sea Water, the upper layers of the MOC. The Atlantic Ocean is the second-largest of the world's oceans, with an area of about 106,460,000 km 2 (41,100,000 sq mi). [62], In the Falkland segment rifting began with dextral movements between the Patagonia and Colorado sub-plates between the Early Jurassic (190 Ma) and the Early Cretaceous (126.7 Ma). [31] The exploration of the MAR in the 1950s led to the general acceptance of seafloor spreading and plate tectonics. 60,000 years ago? Along its path across Earth the composition of the NADW is affected by other water masses, especially Antarctic Bottom Water and Mediterranean Overflow Water. ", "The great American schism: divergence of marine organisms after the rise of the Central American Isthmus", "On the Movements of the North Atlantic Subpolar Front in the Preinstrumental Past", "Coastal South Africa and the Coevolution of the Modern Human Lineage and the Coastal Adaptation", "Stone age people in a changing South African greater Cape Floristic Region", "Stability of the thermohaline circulation under millennial CO2 forcing and two alternative controls on Atlantic salinity", "The Discovery of America: The first Americans may have swept the Western Hemisphere and decimated its fauna within 1000 years", "Extensive 200-million-year-old continental flood basalts of the Central Atlantic Magmatic Province", "Why did modern human populations disperse from Africa ca. [65] Human history thus begins on the coasts of South Africa where the Atlantic Benguela Upwelling and Indian Ocean Agulhas Current meet to produce an intertidal zone on which shellfish, fur seal, fish and sea birds provided the necessary protein sources. This system of currents transport warm water into the North Atlantic, without which temperatures in the North Atlantic and Europe would plunge dramatically. A settlement on Greenland was established before 1000 CE, but contact with it was lost in 1409 and it was finally abandoned during the early Little Ice Age. The reduced quantities of shells in the lower levels can represent the few shells that were exported inland.[72]. Limited data makes the state of redfishes and deep-water species difficult to assess but most likely they remain vulnerable to overfishing. The swimming … Overfishing in the area was recognised as early as the 1960s but, because this was occurring on international waters, it took until the late 1970s before any attempts to regulate was made. Pelagic fish stocks are considered fully fished or overfished, with sardines south of Cape Bojador the notable exception. Its eastern portion includes eddying branches of the North Atlantic Current which transport warm, saline waters from the subtropics to the north-eastern Atlantic. [24], The MAR divides the Atlantic longitudinally into two-halves, in each of which a series of basins are delimited by secondary, transverse ridges. On the African east coast the small cyclonic Angola Gyre lies embedded in the large subtropical gyre. The earliest evidence for the complex behavior associated with this behavioral modernity has been found in the Greater Cape Floristic Region (GCFR) along the coast of South Africa. [26] The depth of water at the apex of the ridge is less than 2,700 m (1,500 fathoms; 8,900 ft) in most places, while the bottom of the ridge is three times as deep. Météo des plages de l'océan Atlantique La façade Atlantique dispose en majorité de grandes plages de sable fin, souvent bien animées tout au long de l'année. Evaporation, precipitation, river inflow and sea ice melting influence surface salinity values. [2][3] It covers approximately 20 percent of Earth's surface and about 29 percent of its water surface area. [17], The Atlantic has irregular coasts indented by numerous bays, gulfs and seas. [50], The break-up of Pangaea began in the Central Atlantic, between North America and Northwest Africa, where rift basins opened during the Late Triassic and Early Jurassic. Following these explorations, Spain and Portugal quickly conquered and colonized large territories in the New World and forced the Amerindian population into slavery in order to explore the vast quantities of silver and gold they found. During the LGM the Laurentide Ice Sheet covered most of northern North America while Beringia connected Siberia to Alaska. To the east, the boundaries of the ocean proper are Europe: the Strait of Gibraltar (where it connects with the Mediterranean Sea—one of its marginal seas—and, in turn, the Black Sea, both of which also touch upon Asia) and Africa. [52] While their middens resemble 12–11 kya-old Late Stone Age (LSA) middens found on every inhabited continent, the 50–45 kya-old Enkapune Ya Muto in Kenya probably represents the oldest traces of the first modern humans to disperse out of Africa. [55], Seafloor spreading led to the extension of the crust and formations of troughs and sedimentary basins. [61], In the central segment rifting started to break Africa in two by opening the Benue Trough around 118 Ma. The Atlantic Ocean is the second-largest of the world's oceans, with an area of about 106,460,000 km2 (41,100,000 sq mi). During the 21st century some species have shown weak signs of recovery, including Greenland halibut, yellowtail flounder, Atlantic halibut, haddock, spiny dogfish, while other stocks shown no such signs, including cod, witch flounder, and redfish. [67], Mitochondrial DNA (mtDNA) studies indicate that 80–60,000 years ago a major demographic expansion within Africa, derived from a single, small population, coincided with the emergence of behavioral complexity and the rapid MIS 5–4 environmental changes. In general, winds transport moisture and air over land areas. [24], Continental shelves in the Atlantic are wide off Newfoundland, southernmost South America, and north-eastern Europe. Dyke swarms in Brazil, Angola, eastern Paraguay, and Namibia, however, suggest the LIP originally covered a much larger area and also indicate failed rifts in all these areas. Stocks of northern shrimp and Norwegian lobster are in good condition. The exact timing is controversial with estimates ranging from 200 to 170 Ma. [6], On average, the Atlantic is the saltiest major ocean; surface water salinity in the open ocean ranges from 33 to 37 parts per thousand (3.3–3.7%) by mass and varies with latitude and season. Mises à … Prévisions des conditions de baignade : température de l'eau, indice UV et état de la mer. Minimum : 33°F/Maximum : 84°F Température de l'eau de l'océan atlantique en février Icebergs are common from early February to the end of July across the shipping lanes near the Grand Banks of Newfoundland. The term dates to as early as 1640, first appearing in print in pamphlet released during the reign of Charles I, and reproduced in 1869 in Nehemiah Wallington's Historical Notices of Events Occurring Chiefly in The Reign of Charles I, where "great Pond" is used in reference to the Atlantic Ocean by Francis Windebank, Charles I's Secretary of State.[14][15][16]. Evidence from the southwest Iberia margin", "Norse Greenland settlement: reflections on climate change, trade, and the contrasting fates of human settlements in the North Atlantic islands", "Volumes of the World's Oceans from ETOPO1", The State of World Fisheries and Aquaculture, "Cyclonic gyre in the tropical South Atlantic", "Emergence of modern human behavior: Middle Stone Age engravings from South Africa", "The beginnings of the Sargasso assemblage in the Tethys? The residence time of the gyre is 4.4–8.5 years. The coldest zones are in high latitudes, with the coldest regions corresponding to the areas covered by sea ice. L'eau se refroidit, se mélange à de l'eau froide venant de l'océan arctique, et devient si dense qu'elle descend, au sud et à l'est du Groenland. [85], Various international treaties attempt to reduce pollution caused by environmental threats such as oil spills, marine debris, and the incineration of toxic wastes at sea. A new model", "History of NOAA Ocean Exploration: Timeline", "The human genetic history of the Americas: the final frontier", "Two millennia of North Atlantic seasonality and implications for Norse colonies", "Global continental and ocean basin reconstructions since 200Ma", "Tracing the flow of North Atlantic Deep Water using chlorofluorocarbons", "On the water masses and mean circulation of the South Atlantic Ocean", "A new scheme for the opening of the South Atlantic Ocean and the dissection of an Aptian salt basin", "The North Atlantic subpolar gyre in four high-resolution models", "Mapping of the Puerto Rico Trench, the Deepest Part of the Atlantic, is Nearing Completion", "The Red Atlantic: American Indigenes and the Making of the Modern World, 1000–1927", "Changes in tropical cyclone number, duration, and intensity in a warming environment", "Map of Atlantic Coast of North America from the Chesapeake Bay to Florida", https://en.wikipedia.org/w/index.php?title=Atlantic_Ocean&oldid=994576088, Short description is different from Wikidata, Wikipedia introduction cleanup from December 2020, Articles covered by WikiProject Wikify from December 2020, All articles covered by WikiProject Wikify, All Wikipedia articles written in American English, Articles using infobox body of water without pushpin map, Articles using infobox body of water without image bathymetry, Articles containing Ancient Greek (to 1453)-language text, Articles to be expanded from December 2020, Articles with dead external links from June 2019, Articles with permanently dead external links, Articles with dead external links from May 2019, Articles with dead external links from July 2017, Wikipedia articles with WORLDCATID identifiers, Creative Commons Attribution-ShareAlike License, 111,866 km (69,510 mi) including marginal seas, This page was last edited on 16 December 2020, at 12:50. [6], The high surface salinity in the Atlantic, on which the Atlantic thermohaline circulation is dependent, is maintained by two processes: the Agulhas Leakage/Rings, which brings salty Indian Ocean waters into the South Atlantic, and the "Atmospheric Bridge", which evaporates subtropical Atlantic waters and exports it to the Pacific. Hi/Low, RealFeel®, precip, radar, & everything you need to be ready for the day, commute, and weekend! The continental margins and continental shelf mark lower density, but greater thickness felsic continental rock that often much older than that of the seafloor. Jusqu’à 200 mètres de profondeur, la température est à peu près égale à celle de la surface, soit 17,5 °C en moyenne, avec un maximum de 27-28 °C dans les océans tropicaux et un minimum de -1,8 °C dans les eaux polaires. Both these currents receive some contribution from the Indian Ocean. The measurements for the water temperature in Fort Lauderdale, Florida are provided by the daily satellite readings provided by the NOAA. By end of the 17th century, the volume of the Trans-Atlantic trade had surpassed that of the Mediterranean trade. [46], Climate is influenced by the temperatures of the surface waters and water currents as well as winds. Another important species was the Brazilian sardinella, with a production of 100,000 tons in 2013 it is now considered overfished. The Gulf Stream also keeps extreme temperatures from occurring on the Florida Peninsula. The Atlantic Subarctic Upper Water in the northernmost North Atlantic is the source for Subarctic Intermediate Water and North Atlantic Intermediate Water. Our sailing weather forecasts are derived using data from the most trusted and reliable weather models available. [71], The same development can be seen in Europe. [86], In 1497 John Cabot became the first Western European since the Vikings to explore mainland North America and one of his major discoveries was the abundant resources of Atlantic cod off Newfoundland. The oldest known mentions of an "Atlantic" sea come from Stesichorus around mid-sixth century BC (Sch. [11] In contrast, the term "Atlantic" originally referred specifically to the Atlas Mountains in Morocco and the sea off the Strait of Gibraltar and the North African coast. [49], In many places, the continental shelf and continental slope are covered in thick sedimentary layers.