The Panama Canal is an artificial 82 km waterway in Panama that connects the Atlantic Ocean with the Pacific Ocean. The canal is a conduit for maritime trade. Canal locks are at each end to lift ships up to Gatun Lake, an artificial lake created to reduce the amount of excavation work required for the canal, 26 m above sea level, lower the ships at the other end; the original locks are 34 m wide. A third, wider lane of locks was constructed between September 2007 and May 2016; the expanded canal began commercial operation on June 26, 2016. The new locks allow transit of larger, post-Panamax ships, capable of handling more cargo. France began work on the canal in 1881, but stopped due to engineering problems and a high worker mortality rate; the United States took over the project in 1904 and opened the canal on August 15, 1914. One of the largest and most difficult engineering projects undertaken, the Panama Canal shortcut reduced the time for ships to travel between the Atlantic and Pacific Oceans, enabling them to avoid the lengthy, hazardous Cape Horn route around the southernmost tip of South America via the Drake Passage or Strait of Magellan.
Colombia and the United States controlled the territory surrounding the canal during construction. The US continued to control the canal and surrounding Panama Canal Zone until the 1977 Torrijos–Carter Treaties provided for handover to Panama. After a period of joint American–Panamanian control, in 1999, the canal was taken over by the Panamanian government, it is now operated by the government-owned Panama Canal Authority. Annual traffic has risen from about 1,000 ships in 1914, when the canal opened, to 14,702 vessels in 2008, for a total of 333.7 million Panama Canal/Universal Measurement System tons. By 2012, more than 815,000 vessels had passed through the canal, it takes 11.38 hours to pass through the Panama Canal. The American Society of Civil Engineers has ranked the Panama Canal one of the seven wonders of the modern world; the earliest mention of a canal across the Isthmus of Panama occurred in 1534, when Charles V, Holy Roman Emperor and King of Spain, ordered a survey for a route through the Americas that would ease the voyage for ships traveling between Spain and Peru.
Such a route would have given the Spanish a military advantage over the Portuguese. In 1668, the English physician and philosopher Sir Thomas Browne speculated in his encyclopaedic endeavour Pseudodoxia Epidemica - "some Isthmus have been eat through by the Sea, others cut by the spade: And if policy would permit, that of Panama in America were most worthy the attempt: it being but few miles over, would open a shorter cut unto the East Indies and China". In 1788, American Thomas Jefferson Minister to France, suggested that the Spanish should build the canal since it would be a less treacherous route for ships than going around the southern tip of South America, that tropical ocean currents would widen the canal thereafter. During an expedition from 1788 to 1793, Alessandro Malaspina outlined plans for its construction. Given the strategic location of Panama and the potential offered by its narrow isthmus separating two great oceans, other trade links in the area were attempted over the years.
The ill-fated Darien scheme was launched by the Kingdom of Scotland in 1698 to set up an overland trade route. Inhospitable conditions thwarted the effort and it was abandoned in April 1700. Numerous canals were built in other countries in the late early 19th centuries; the success of the Erie Canal in the United States in the 1820s and the collapse of the Spanish Empire in Latin America led to a surge of American interest in building an inter-oceanic canal. Beginning in 1826, US officials began negotiations with Gran Colombia, hoping to gain a concession for the building of a canal. Jealous of their newly obtained independence and fearing that they would be dominated by an American presence, the president Simón Bolívar and New Granada officials declined American offers; the new nation was politically unstable, Panama rebelled several times during the 19th century. Another effort was made in 1843. According to the New York Daily Tribune, August 24, 1843, a contract was entered into by Barings of London and the Republic of New Granada for the construction of a canal across the Isthmus of Darien.
They referred to it as the Atlantic and Pacific Canal, it was a wholly British endeavor. It was expected to be completed in five years. At nearly the same time, other ideas were floated, including a canal across Mexico's Isthmus of Tehuantepec. Nothing came of that plan, either. In 1846, the Mallarino–Bidlack Treaty, negotiated between the US and New Granada, granted the United States transit rights and the right to intervene militarily in the isthmus. In 1848, the discovery of gold in California, on the West Coast of the United States, created great interest in a crossing between the Atlantic and Pacific oceans. William H. Aspinwall, the man who won the federal subsidy for the building and operating the Pacific mail steamships at around the same time, benefited from this discovery. Aspinwall's route included steamship legs from New York City to Panama and from Panama to California, with an overland portage through Panama; the route between California and Panama was soon traveled, as it provided one of the fastest links between San Francisco and the East Coast cities, about 40 days' transit in total.
Nearly all the gold, shipped out of California went by the fast Panama route. Several new and larger paddle steamers were soon plying
Geographic coordinate system
A geographic coordinate system is a coordinate system that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position and two or three of the numbers represent a horizontal position. A common choice of coordinates is latitude and elevation. To specify a location on a plane requires a map projection; the invention of a geographic coordinate system is credited to Eratosthenes of Cyrene, who composed his now-lost Geography at the Library of Alexandria in the 3rd century BC. A century Hipparchus of Nicaea improved on this system by determining latitude from stellar measurements rather than solar altitude and determining longitude by timings of lunar eclipses, rather than dead reckoning. In the 1st or 2nd century, Marinus of Tyre compiled an extensive gazetteer and mathematically-plotted world map using coordinates measured east from a prime meridian at the westernmost known land, designated the Fortunate Isles, off the coast of western Africa around the Canary or Cape Verde Islands, measured north or south of the island of Rhodes off Asia Minor.
Ptolemy credited him with the full adoption of longitude and latitude, rather than measuring latitude in terms of the length of the midsummer day. Ptolemy's 2nd-century Geography used the same prime meridian but measured latitude from the Equator instead. After their work was translated into Arabic in the 9th century, Al-Khwārizmī's Book of the Description of the Earth corrected Marinus' and Ptolemy's errors regarding the length of the Mediterranean Sea, causing medieval Arabic cartography to use a prime meridian around 10° east of Ptolemy's line. Mathematical cartography resumed in Europe following Maximus Planudes' recovery of Ptolemy's text a little before 1300. In 1884, the United States hosted the International Meridian Conference, attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich, England as the zero-reference line; the Dominican Republic voted against the motion, while Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911.
In order to be unambiguous about the direction of "vertical" and the "horizontal" surface above which they are measuring, map-makers choose a reference ellipsoid with a given origin and orientation that best fits their need for the area they are mapping. They choose the most appropriate mapping of the spherical coordinate system onto that ellipsoid, called a terrestrial reference system or geodetic datum. Datums may be global, meaning that they represent the whole Earth, or they may be local, meaning that they represent an ellipsoid best-fit to only a portion of the Earth. Points on the Earth's surface move relative to each other due to continental plate motion and diurnal Earth tidal movement caused by the Moon and the Sun; this daily movement can be as much as a metre. Continental movement can be up to 10 m in a century. A weather system high-pressure area can cause a sinking of 5 mm. Scandinavia is rising by 1 cm a year as a result of the melting of the ice sheets of the last ice age, but neighbouring Scotland is rising by only 0.2 cm.
These changes are insignificant if a local datum is used, but are statistically significant if a global datum is used. Examples of global datums include World Geodetic System, the default datum used for the Global Positioning System, the International Terrestrial Reference Frame, used for estimating continental drift and crustal deformation; the distance to Earth's center can be used both for deep positions and for positions in space. Local datums chosen by a national cartographical organisation include the North American Datum, the European ED50, the British OSGB36. Given a location, the datum provides the latitude ϕ and longitude λ. In the United Kingdom there are three common latitude and height systems in use. WGS 84 differs at Greenwich from the one used on published maps OSGB36 by 112 m; the military system ED50, used by NATO, differs from about 120 m to 180 m. The latitude and longitude on a map made against a local datum may not be the same as one obtained from a GPS receiver. Coordinates from the mapping system can sometimes be changed into another datum using a simple translation.
For example, to convert from ETRF89 to the Irish Grid add 49 metres to the east, subtract 23.4 metres from the north. More one datum is changed into any other datum using a process called Helmert transformations; this involves converting the spherical coordinates into Cartesian coordinates and applying a seven parameter transformation, converting back. In popular GIS software, data projected in latitude/longitude is represented as a Geographic Coordinate System. For example, data in latitude/longitude if the datum is the North American Datum of 1983 is denoted by'GCS North American 1983'; the "latitude" of a point on Earth's surface is the angle between the equatorial plane and the straight line that passes through that point and through the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the Equator and to each other; the North Pole is 90° N. The 0° parallel of latitude is designated the Equator, the fun
Anguilla is a British overseas territory in the Caribbean. It is one of the most northerly of the Leeward Islands in the Lesser Antilles, lying east of Puerto Rico and the Virgin Islands and directly north of Saint Martin; the territory consists of the main island of Anguilla 16 miles long by 3 miles wide at its widest point, together with a number of much smaller islands and cays with no permanent population. The island's capital is The Valley; the total land area of the territory is 35 square miles, with a population of 14,764. Anguilla has become a popular tax haven, having no capital gains, profit, sales, or corporate taxes. In April 2011, faced with a mounting deficit, it introduced a 3% "Interim Stabilisation Levy", Anguilla's first form of income tax. Anguilla has a 0.75% property tax. The name Anguilla is from the Italian anguilla meaning "eel" in reference to the island's shape, it is believed by most sources to have been named by Christopher Columbus. For similar reasons, it was known as Snake or Snake Island.
Anguilla was first settled by Indigenous Amerindian peoples. The earliest Native American artefacts found on Anguilla have been dated to around 1300 BC; the Arawak name for the island seems to have been Malliouhana. The date of European colonisation is uncertain: some sources claim that Columbus sighted the island during his second voyage in 1493, while others state that the island's first European explorer was the French Huguenot nobleman and merchant mariner René Goulaine de Laudonnière in 1564; the Dutch West India Company established a fort on the island in 1631. The Dutch withdrew after the destruction of the fort by Spanish forces in 1633. Traditional accounts state that Anguilla was first colonized by English settlers from Saint Kitts beginning in 1650. In this early colonial period, Anguilla sometimes served as a place of refuge and recent scholarship focused on Anguilla has placed greater significance on other Europeans and creoles migrating from St. Christopher, Barbados and Antigua.
The French temporarily took over the island in 1666 but returned it to English control under the terms of the Treaty of Breda the next year. A Major John Scott who visited in September 1667, wrote of leaving the island "in good condition" and noted that in July 1668, "200 or 300 people fled thither in time of war", it is that some of these early Europeans brought enslaved Africans with them. Historians confirm. For example, Africans from Senegal lived in St. Christopher in 1626. By 1672 a slave depot existed on the island of Nevis. While the time of African arrival in Anguilla is difficult to place archival evidence indicates a substantial African presence of at least 100 enslaved people by 1683; these seem to have come from Central Africa as well as West Africa. Attempts by the French to capture the island during the War of Austrian Succession and the Napoleonic Wars ended in failure. During the early colonial period, Anguilla was administered by the British through Antigua. In 1967, Britain granted Saint Nevis full internal autonomy.
Anguilla was incorporated into the new unified dependency, named Saint Christopher-Nevis-Anguilla, against the wishes of many Anguillians. This led to two Anguillian Revolutions in 1969 headed by Atlin Harrigan and Ronald Webster; the island operated as the independent "Republic of Anguilla". The goal of the revolution was not independence per se, but rather independence from Saint Kitts and Nevis and a return to being a British colony. British authority was restored in July 1971. Anguilla is an internally self-governing overseas territory of the United Kingdom, its politics take place in a framework of a parliamentary representative democratic dependency, whereby the Chief Minister is the head of government, of a pluriform multi-party system. The United Nations Committee on Decolonization includes Anguilla on the United Nations list of Non-Self-Governing Territories; the territory's constitution is Anguilla Constitutional Order 1 April 1982. Executive power is exercised by the government. Legislative power is vested in the House of Assembly.
The judiciary is independent of the legislature. As a dependency of the UK, the UK is responsible for Anguilla's military defence, although there are no active garrisons or armed forces present. Anguilla has a small marine police force, comprising around 32 personnel, which operates one VT Halmatic M160-class 52-foot fast patrol boat; the majority of residents are black, the descendants of slaves transported from Africa. Minorities include whites at 3.74% and people of mixed race at 4.65%. 72 % of the population is Anguillian. Of the non-Anguillian population, many are citizens of the United States, United Kingdom, St Kitts & Nevis, the Dominican Republic and Nigeria. 2006 and 2007 saw an influx of large numbers of Chinese and Mexican workers, brought in as labour for major tourist developments due to the local population not being large enough to support the labour requirements. Christian churches did not have a consistent or strong presence during the initial period of English colonisation. Spiritual and religious practic
Sombrero known as Hat Island, is part of the British overseas territory of Anguilla and is the northernmost island of the Lesser Antilles. It lies 54 km north-west of Anguilla across Prickly Pear Passage; the distance to Dog Island, the next nearest island of Anguilla, is 38 kilometres. Sombrero is 1.67 kilometres long north-south, 0.38 km wide. The land area is 0.38 km2. When viewed from the sea, the island had the shape of a sombrero hat but guano mining operations have left the island with precipitous sides and a flat top, 12 m above sea level; the surface of the island is rough, vegetation is sparse. The guano-mining operation yielded some 3000 tons of phosphate a year by 1870. By 1890, the phosphate reserves had been exhausted; the lighthouse marks the Anegada Passage, the route from Europe into the Caribbean. The first lighthouse was erected in 1868. In 1960, Hurricane Donna damaged this lighthouse, with the result that a new lighthouse replaced it in 1962; the lighthouses were manned from 1868 to 2001.
In that year, Trinity House donated and installed the current, automated tower, a 15 m round tower, painted white. Anguilla's Department of Fisheries and Marine Resources is responsible for the maintenance of the navigational aids; as a result of the Treaty of Utrecht in 1714, Sombrero passed into the hands of the British. Captain Warwick Lake of Recruit marooned an impressed seaman, Robert Jeffrey, there on 13 December 1807; as it turned out, Jeffrey survived. A passing American vessel, the schooner Adams from Marblehead, had rescued him. Still, a court martial dismissed Lake from the Royal Navy. In 1814, again in 1825, a British geologist surveyed the island and found that it abounded in guano and reported this to the British government. In 1856 the Americans claimed the island, in a short period of time quarried 100,000 tons of phosphate that served as fertilizer for the exhausted lands of the Southern States. Uniquely, an important insurrection occurred when West Indian black workers revolted against the “slavery proclivities” of a white American superintendent vis-à-vis wage-earning free men.
Four of the 200 workers "fatally injured" Superintendent Snow and commandeered the island and company money and stores. The British intervened and demanded compensation from the United States for the occupation; the conflicting claims to the island were settled in Britain's favour in 1867. Sombrero, lying in the route of shipping from England to South and Central America, lay in an area with many hazards and in 1848 the Admiralty was asked to install a light on it. On 30 June 1859, the Royal Mail Steam Packet Company's ship Paramatta was wrecked on her maiden voyage on Horseshoe Reef, which resulted in another request to the Admiralty; the lighthouse was built and first exhibited its light on the evening of 1 January 1868. Paramatta and the Lighthouse built following her demise were both constructed by the same shipyard, the Thames Ironworks and Shipbuilding Company, on the banks of the River Lea in Blackwall, London. Paramatta was the last ship launched from their Middlesex bank, while the lighthouse was built on the Essex side, the yard occupying premises on either side of the river.
In 1871, the lease of the island was sold for £55,000 and sold again for £110,000 to the New Sombrero Phosphate Company, which led to litigation in Erlanger v. New Sombrero Phosphate Co 3 App Cas 1218. From the early 1870s until 1885, a Cornish mining engineer, Thomas Corfield, was Superintendent of Sombrero, his duties included organizing the conveying of the guano to a spot, convenient for loading the lighters to take the guano to the ships lying off the island, overseeing the construction of derricks and engine houses, arranging for the laying of the tram lines for the wagons, which were loaded at the quarries. The guano was just piled in dumps near the engine derricks. There was no semblance of no beach; the black workers were recruited from various islands and lived in wooden huts during their term of service. Stores and various supplies were obtained from a merchant at Sint Maarten, a Mr Nesbit; the company's schooner Logos brought supplies and took the black labourers to and from their homes on the other islands.
The superintendent's house was a wooden bungalow near the middle of the island, around it were grouped the quarters of the technicians, store keepers, lighthouse keepers, other wooden buildings. On the side opposite to the main buildings was a small building for the superintendent. There was a wide veranda round the house and he used to live there with his family, except near the hurricane season. In 1890, the phosphate works on the island were abandoned and by 1893 the lighthouse had come under the authority of the British Board of Trade the Department of Transport. Administration of the light was carried out by Trinity House. In 1931, the old light system was changed and improved to 200,000 candle power and the tower received its first major repair when the basement was encased in concrete. On 20 July 1962, after the destruction caused by Hurricane Donna in 1960, the present lighthouse was put into operation and the old tower demolished on 28 July 1962; the lighthouse is located near the centre of the island, reaches a height of 166 feet above sea level.
It protects ships passing from the Atlantic Ocean to the Caribbean Sea through the Anegada Passage. Full responsibility for the light passed from Trinity House to the Anguillan government on 1 December 2001; until the only inhabitants were the staff of the lighthouse but the light was automated in 2002 and now the island is uninhabit
British Virgin Islands
The British Virgin Islands simply the Virgin Islands, are a British Overseas Territory in the Caribbean, to the east of Puerto Rico. The islands are geographically part of the Virgin Islands archipelago and are located in the Leeward Islands of the Lesser Antilles; the British Virgin Islands consist of the main islands of Tortola, Virgin Gorda and Jost Van Dyke, along with over 50 other smaller islands and cays. About 15 of the islands are inhabited; the capital, Road Town, is on Tortola, the largest island, about 20 km long and 5 km wide. The islands had a population of about 28,000 at the 2010 Census, of whom 23,500 lived on Tortola. For the islands, the latest United Nations estimate is 30,661. British Virgin Islanders are British Overseas Territories citizens and since 2002 are British citizens as well. Although the territory is not part of the European Union and not directly subject to EU law, British Virgin Islanders are deemed to be citizens of the EU by virtue of their British citizenship.
The official name of the territory is still the "Virgin Islands", but the prefix "British" is used. This is believed to distinguish it from the neighbouring American territory which changed its name from the "Danish West Indies" to "Virgin Islands of the United States" in 1917. However, local historians have disputed this, pointing to a variety of publications and public records dating from between 21 February 1857 and 12 September 1919 where the Territory is referred to as the British Virgin Islands. British Virgin Islands government publications continue to begin with the name "The territory of the Virgin Islands", the territory's passports refer to the "Virgin Islands", all laws begin with the words "Virgin Islands". Moreover, the territory's Constitutional Commission has expressed the view that "every effort should be made" to encourage the use of the name "Virgin Islands", but various public and quasi-public bodies continue to use the name "British Virgin Islands" or "BVI", including BVI Finance, BVI Electricity Corporation, BVI Tourist Board, BVI Athletic Association, BVI Bar Association and others.
In 1968 the British Government issued a memorandum requiring that the postage stamps in the territory should say "British Virgin Islands", a practice, still followed today. This was to prevent confusion following on from the adoption of US currency in the Territory in 1959, the references to US currency on the stamps of the Territory; the Virgin Islands were first settled by the Arawak from South America around 100 BC. The Arawaks inhabited the islands until the 15th century when they were displaced by the more aggressive Caribs, a tribe from the Lesser Antilles islands, after whom the Caribbean Sea is named; the first European sighting of the Virgin Islands was by the Spanish expedition of Christopher Columbus in 1493 on his second voyage to the Americas. Columbus gave them the fanciful name Santa Ursula y las Once Mil Vírgenes, shortened to Las Vírgenes, after the legend of Saint Ursula; the Spanish Empire claimed the islands by discovery in the early 16th century, but never settled them, subsequent years saw the English, French and Danish all jostling for control of the region, which became a notorious haunt for pirates.
There is no record of any native Amerindian population in the British Virgin Islands during this period, although most of the native population on nearby Saint Croix was killed or dispersed. The Dutch established a permanent settlement on the island of Tortola by 1648. In 1672, the English captured Tortola from the Dutch, the English annexation of Anegada and Virgin Gorda followed in 1680. Meanwhile, over the period 1672–1733, the Danish gained control of the nearby islands of Saint Thomas, Saint John and Saint Croix; the British islands were considered principally a strategic possession, but were planted when economic conditions were favourable. The British introduced sugar cane, to become the main crop and source of foreign trade, slaves were brought from Africa to work on the sugar cane plantations; the islands prospered economically until the middle of the nineteenth century, when a combination of the abolition of slavery in the territory, a series of disastrous hurricanes, the growth in the sugar beet crop in Europe and the United States reduced sugar cane production and led to a period of economic decline.
In 1917, the United States purchased St. John, St. Thomas, St. Croix from Denmark for US$25 million, renaming them the United States Virgin Islands; the British Virgin Islands were administered variously as part of the British Leeward Islands or with St. Kitts and Nevis, with an administrator representing the British Government on the islands; the islands gained separate colony status in 1960 and became autonomous in 1967. Since the 1960s, the islands have diversified away from their traditionally agriculture-based economy towards tourism and financial services, becoming one of the wealthiest areas in the Caribbean; the British Virgin Islands comprise around 60 tropical Caribbean islands, ranging in size from the largest, being 20 km long and 5 km wide, to tiny uninhabited islets, altogether about 150 square kilometres in extent. They are located in the Virgin Islands archipelago, a few miles east of the US Virgin Islands, about 95 km from the Puerto Rican mainland. About 150 km east south-east lies Anguilla.
The North Atlantic Ocean lies to the east of the islands, the Caribbean Sea lies to the
The Atlantic Ocean is the second largest of the world's oceans, with an area of about 106,460,000 square kilometers. It covers 20 percent of the Earth's surface and about 29 percent of its water surface area, it separates the "Old World" from the "New World". The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, the Americas to the west; as one component of the interconnected global ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, the Southern Ocean in the south. The Equatorial Counter Current subdivides it into the North Atlantic Ocean and the South Atlantic Ocean at about 8°N. 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; the oldest known mentions of an "Atlantic" sea come from Stesichorus around mid-sixth century BC: Atlantikoi pelágei and in The Histories of Herodotus around 450 BC: Atlantis thalassa where the name refers to "the sea beyond the pillars of Heracles", said to be part of the sea that surrounds all land.
Thus, on one hand, the name refers to Atlas, the Titan in Greek mythology, who supported the heavens and who appeared as a frontispiece in Medieval maps and lent his name to modern atlases. On the other hand, to early Greek sailors and in Ancient Greek mythological literature such as the Iliad and the Odyssey, this all-encompassing ocean was instead known as Oceanus, the gigantic river that encircled the world. In contrast, the term "Atlantic" referred to the Atlas Mountains in Morocco and the sea off the Strait of Gibraltar and the North African coast; the Greek word thalassa has been reused by scientists for the huge Panthalassa ocean that surrounded the supercontinent Pangaea hundreds of millions of years ago. The term "Aethiopian Ocean", derived from Ancient Ethiopia, was applied to the Southern Atlantic as late as the mid-19th century. During the Age of Discovery, the Atlantic was known to English cartographers as the Great Western Ocean; the term The Pond is used by British and American speakers in context to the Atlantic Ocean, as a form of meiosis, or sarcastic understatement.
The term dates to as early as 1640, first appearing in print in pamphlet released during the reign of Charles I, 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. The International Hydrographic Organization defined the limits of the oceans and seas in 1953, but some of these definitions have been revised since and some are not used by various authorities and countries, see for example the CIA World Factbook. Correspondingly, the extent and number of oceans and seas varies; the Atlantic Ocean is bounded on the west by South America. It connects to the Arctic Ocean through the Denmark Strait, Greenland Sea, Norwegian Sea and Barents Sea. To the east, the boundaries of the ocean proper are Europe: the Strait of Africa. In the southeast, the Atlantic merges into the Indian Ocean; the 20° East meridian, running south from Cape Agulhas to Antarctica defines its border.
In the 1953 definition it extends south to Antarctica, while in maps it is bounded at the 60° parallel by the Southern Ocean. The Atlantic has irregular coasts indented by numerous bays and seas; these include the Baltic Sea, Black Sea, Caribbean Sea, Davis Strait, Denmark Strait, part of the Drake Passage, Gulf of Mexico, Labrador Sea, Mediterranean Sea, North Sea, Norwegian Sea all of the Scotia Sea, other tributary water bodies. Including these marginal seas the coast line of the Atlantic measures 111,866 km compared to 135,663 km for the Pacific. Including its marginal seas, the Atlantic covers an area of 106,460,000 km2 or 23.5% of the global ocean and has a volume of 310,410,900 km3 or 23.3% of the total volume of the earth's oceans. Excluding its marginal seas, the Atlantic covers 81,760,000 km2 and has a volume of 305,811,900 km3; the North Atlantic covers 41,490,000 km2 and the South Atlantic 40,270,000 km2. The average depth is 3,646 m and the maximum depth, the Milwaukee Deep in the Puerto Rico Trench, is 8,486 m.
The bathymetry of the Atlantic is dominated by a submarine mountain range called the Mid-Atlantic Ridge. It runs from 87°N or 300 km south of the North Pole to the subantarctic Bouvet Island at 42°S; the MAR divides the Atlantic longitudinally into two halves, in each of which a series of basins are delimited by secondary, transverse ridges. The MAR reaches above 2,000 m 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; the MAR is a barrier for bottom water, but at these two transform faults deep water currents can pass from one side to the othe