Atlantic Ocean

• 1. Origins And Naming

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  The name Atlantic Ocean first appeared in written records around the mid-sixth century BC, attributed to the Greek poet Stesichorus. He used the term to describe a sea beyond the Pillars of Hercules, which modern scholars identify as the Strait of Gibraltar. Herodotus later referenced this same body of water in his Histories around 450 BC, calling it the sea beyond the Atlas Mountains off the West African coast. Ancient Greeks believed this vast expanse was part of Oceanus, a great river surrounding all landmasses mentioned in myths like the Iliad and Odyssey. They contrasted this open ocean with enclosed seas they knew well, such as the Mediterranean and Black Sea. The name itself derives from Atlas, the Titan who supported the heavens in Greek mythology. Medieval maps often depicted Atlas as a frontispiece holding up the world. During the Age of Discovery, English cartographers referred to this body of water as the Great Western Ocean. A humorous British and American term called the pond emerged in 1640, appearing in print during the reign of Charles I. Francis Windebank, Secretary of State to Charles I, used the phrase great Pond to describe the Atlantic Ocean in historical notices published in 1869. This ironic understatement emphasized the connection and division between Britain and its former colonies rather than discussing the ocean itself.

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• 2. Geological Formation

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  The Mid-Atlantic Ridge runs from south of the North Pole at 87°N down to Bouvet Island at 54°S, dividing the Atlantic longitudinally into two halves. This submarine mountain range rises above the surrounding ocean floor and creates rift valleys where tectonic plates diverge. In the North Atlantic, these are the North American and Eurasian plates, while the South Atlantic features the South American and African plates. The Challenger expedition discovered parts of this ridge in the 1870s, followed by the German Meteor expedition which mapped the remainder using echo-sounding equipment in the 1920s. Seafloor spreading led to crust extension and the formation of troughs and sedimentary basins over millions of years. Iceland began forming 62 million years ago due to a concentrated mantle plume that erupted large quantities of basalt across Baffin Island, Greenland, the Faroe Islands, and Scotland. The break-up of Pangaea started in the central Atlantic during the Late Triassic and Early Jurassic periods, approximately 200 to 170 million years ago. Volcanic activity from the Central Atlantic Magmatic Province covered areas now known as northern and central Brazil with an estimated volume of lava flows reaching thousands of cubic kilometers. The oldest oceanic crust in the Atlantic is up to 145 million years old and sits off the west coast of Africa and east coast of North America.

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• 3. Oceanic Circulation

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  Surface water temperatures range from below freezing near polar regions to over 30 degrees Celsius north of the equator. The Gulf Stream flows northeast from Cape Hatteras along the North American coast, transporting warm water into the North Atlantic without which European winters would plunge dramatically. This current system includes the North Atlantic Current branching toward the Grand Banks and the Subpolar Front separating subtropical gyres from subpolar ones. South Atlantic water circulates counter-clockwise while North Atlantic water moves clockwise due to the Coriolis effect. The North Atlantic Gyre occupies the northern Atlantic, whereas the South Atlantic Gyre appears in the southern Atlantic moving anti-cyclonically. Warm subtropical waters transform into colder subpolar and polar waters within the Labrador Sea before flowing back to the subtropical gyre. A third of this water becomes part of deep North Atlantic Deep Water that feeds meridional overturning circulation threatened by anthropogenic climate change. Surface salinity ranges from 33 to 37 parts per thousand depending on latitude and season with maximum values occurring around 25° north and south. Evaporation, precipitation, river inflow, and sea ice melting all influence these surface salinity values.

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• 4. Human Exploration History

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  Christopher Columbus reached the Americas in 1492 sailing under the Spanish flag six years after Vasco da Gama proved the Atlantic connected to India via the Cape of Good Hope. Pedro Álvares Cabral reached Brazil in 1500 following currents of the South Atlantic Gyre during his voyage to India. Norse settlements established themselves in the Faroe Islands and Iceland during the 9th and 10th centuries before founding a colony on Greenland prior to 1000 CE. Contact with Greenland was lost in 1409 and finally abandoned during the early Little Ice Age due to unsustainable economies and conflicts with local Inuit populations. John Cabot became the first Western European since the Vikings to explore mainland North America in 1497 discovering abundant cod resources off Newfoundland. Between the 15th century and 1888 when Brazil ended slave trade an estimated 9.5 million enslaved Africans were shipped into the New World for agricultural labor. The slave trade officially abolished in British Empire and United States in 1808 while slavery itself ended in Britain in 1838 and US in 1865 after Civil War. From Columbus to Industrial Revolution trans-Atlantic trade including colonialism and slavery became crucial for Western Europe developing sustained growth between 1500 and 1800.

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• 5. Economic Exploitation

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  The shelves of the Atlantic host some of world's richest fishing resources including Grand Banks of Newfoundland Scotian Shelf Georges Bank Bahama Banks waters around Iceland Irish Sea Bay of Fundy Dogger Bank North Sea Falkland Banks. Fisheries underwent significant changes since 1950s with global catches divided into three groups only two observed in Atlantic where eastern-central southwest oscillate stable value rest decline following historical peaks. Northeast Atlantic total catches decreased between mid-1970s and 1990s reaching 8.7 million tons in 2013 blue whiting peaked at 2.4 million tons in 2004 then dropped to 628,000 tons by 2013. Northwest Atlantic landings fell from 4.2 million tons early 1970s to 1.9 million tons 2013 showing weak recovery signs for Greenland halibut yellowtail flounder Atlantic halibut haddock spiny dogfish while cod witch flounder redfish showed no such improvement. Overfishing recognized as early as 1960s but regulation attempts delayed until late 1970s resulting collapse Atlantic northwest cod fishery early 1990s population deep-sea fishes collapsed process American plaice redfish Greenland halibut together flounder grenadier. The Atlantic harbors petroleum gas fields marine mammals seals whales sand gravel aggregates placer deposits polymetallic nodules precious stones gold deposits mile or two underwater ocean floor encased rock must mined through currently no cost-effective way mine extract profit.

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• 6. Modern Environmental Crisis

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  Marine pollution generic term entry ocean potentially hazardous chemicals particles biggest culprits rivers agriculture fertilizer chemicals livestock human waste excess oxygen-depleting chemicals leads hypoxia creation dead zone. Marine debris known marine litter describes human-created waste floating body water oceanic debris tends accumulate center gyres coastlines frequently washing aground known beach litter North Atlantic garbage patch estimated hundreds kilometers across size. Other pollution concerns include agricultural municipal waste municipal pollution comes eastern United States southern Brazil eastern Argentina oil pollution Caribbean Sea Gulf Mexico Lake Maracaibo Mediterranean Sea North Sea industrial waste municipal sewage Baltic Sea North Sea Mediterranean Sea. A USAF C-124 aircraft from Dover Air Force Base Delaware carrying three nuclear bombs over Atlantic Ocean experienced loss power crew jettisoned two nuclear bombs never recovered. North Atlantic hurricane activity increased past decades because increased sea surface temperature tropical latitudes changes attributed either natural Atlantic Multidecadal Oscillation anthropogenic climate change. A 2005 report indicated Atlantic meridional overturning circulation slowed down 30% between 1957 and 2004 research highlighted significant weakening approximately 12% past two decades. If AMO responsible SST variability AMOC would have increased strength apparently not case clear statistical analyses annual tropical cyclones changes display multidecadal cyclicity therefore changes SST caused human activities.

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