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100-544: Oceanography (from Ancient Greek ὠκεανός ( ōkeanós )  ' ocean ' and γραφή ( graphḗ )  ' writing '), also known as oceanology , sea science , ocean science , and marine science , is the scientific study of the ocean , including its physics , chemistry , biology , and geology . It is an Earth science , which covers a wide range of topics, including ocean currents , waves , and geophysical fluid dynamics ; fluxes of various chemical substances and physical properties within

200-537: A pitch accent . In Modern Greek, all vowels and consonants are short. Many vowels and diphthongs once pronounced distinctly are pronounced as /i/ ( iotacism ). Some of the stops and glides in diphthongs have become fricatives , and the pitch accent has changed to a stress accent . Many of the changes took place in the Koine Greek period. The writing system of Modern Greek, however, does not reflect all pronunciation changes. The examples below represent Attic Greek in

300-667: A commentated translation of earlier work by others, he included a treatise on geometrical and astronomic methods of navigation. There he states clearly that Portuguese navigations were not an adventurous endeavour: "nam se fezeram indo a acertar: mas partiam os nossos mareantes muy ensinados e prouidos de estromentos e regras de astrologia e geometria que sam as cousas que os cosmographos ham dadar apercebidas (...) e leuaua cartas muy particularmente rumadas e na ja as de que os antigos vsauam" (were not done by chance: but our seafarers departed well taught and provided with instruments and rules of astrology (astronomy) and geometry which were matters

400-472: A lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period. They have the same general outline but differ in some of the detail. The only attested dialect from this period is Mycenaean Greek , but its relationship to the historical dialects and

500-503: A lack of wind that he feared would trap them. The sea may have been known to earlier mariners , as a poem by the late fourth century author Avienius describes a portion of the Atlantic as being covered with seaweed and windless, citing a now-lost account by the fifth century BC Carthaginian Himilco the Navigator. Columbus himself was aware of this account and thought Himilco had reached

600-419: A lesser degree. Pamphylian Greek , spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Regarding the speech of the ancient Macedonians diverse theories have been put forward, but the epigraphic activity and the archaeological discoveries in

700-544: A paper on reefs and the formation of atolls as a result of the second voyage of HMS Beagle in 1831–1836. Robert FitzRoy published a four-volume report of Beagle ' s three voyages. In 1841–1842 Edward Forbes undertook dredging in the Aegean Sea that founded marine ecology. The first superintendent of the United States Naval Observatory (1842–1861), Matthew Fontaine Maury devoted his time to

800-543: A prefix /e-/, called the augment . This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect, and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). The two kinds of augment in Greek are syllabic and quantitative. The syllabic augment

900-571: A role in a number of other pioneering research efforts, including William Beebe and Otis Barton 's 1932 dive where they conducted observations of animals and radio broadcasts, John Swallow 's work on the Swallow float in the late 1950s, the discovery of Prochlorococcus by a team of researchers in the 1980s, and various oceanographic data gathering programs such as those of Henry Stommel . In July 1969, British businessman and amateur sailor Donald Crowhurst disappeared after his yacht became mired in

1000-671: A separate historical stage, though its earliest form closely resembles Attic Greek , and its latest form approaches Medieval Greek , and Koine may be classified as Ancient Greek in a wider sense. There were several regional dialects of Ancient Greek; Attic Greek developed into Koine. Ancient Greek was a pluricentric language , divided into many dialects. The main dialect groups are Attic and Ionic , Aeolic , Arcadocypriot , and Doric , many of them with several subdivisions. Some dialects are found in standardized literary forms in literature , while others are attested only in inscriptions. There are also several historical forms. Homeric Greek

1100-609: A standard subject of study in educational institutions of the Western world since the Renaissance . This article primarily contains information about the Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period ( c.  300 BC ), Ancient Greek was followed by Koine Greek , which is regarded as

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1200-460: A systematic scientific large project, sustained over many decades, studying the currents and winds of the Atlantic. The work of Pedro Nunes (1502–1578) is remembered in the navigation context for the determination of the loxodromic curve: the shortest course between two points on the surface of a sphere represented onto a two-dimensional map. When he published his "Treatise of the Sphere" (1537), mostly

1300-510: A vowel or /n s r/ ; final stops were lost, as in γάλα "milk", compared with γάλακτος "of milk" (genitive). Ancient Greek of the classical period also differed in both the inventory and distribution of original PIE phonemes due to numerous sound changes, notably the following: The pronunciation of Ancient Greek was very different from that of Modern Greek . Ancient Greek had long and short vowels ; many diphthongs ; double and single consonants; voiced, voiceless, and aspirated stops ; and

1400-607: A voyage around the Cape of Good Hope in 1777, he mapped "the banks and currents at the Lagullas " . He was also the first to understand the nature of the intermittent current near the Isles of Scilly , (now known as Rennell's Current). The tides and currents of the ocean are distinct. Tides are the rise and fall of sea levels created by the combination of the gravitational forces of the Moon along with

1500-556: Is a literary form of Archaic Greek (derived primarily from Ionic and Aeolic) used in the epic poems , the Iliad and the Odyssey , and in later poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects. The origins, early form and development of the Hellenic language family are not well understood because of

1600-418: Is added to stems beginning with consonants, and simply prefixes e (stems beginning with r , however, add er ). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel: Some verbs augment irregularly; the most common variation is e → ei . The irregularity can be explained diachronically by the loss of s between vowels, or that of the letter w , which affected

1700-502: Is also a body of water that has captured the public imagination, and so is seen in a wide variety of literary and artistic works and in popular culture. A chart drawn by the Catalan cartographer, Gabriel de Vallseca of Mallorca , has been interpreted to indicate that the Azores were first discovered by Diogo de Silves in 1427. In 1431, Gonçalo Velho was dispatched with orders to determine

1800-644: Is called 'East Greek'. Arcadocypriot apparently descended more closely from the Mycenaean Greek of the Bronze Age. Boeotian Greek had come under a strong Northwest Greek influence, and can in some respects be considered a transitional dialect, as exemplified in the poems of the Boeotian poet Pindar who wrote in Doric with a small Aeolic admixture. Thessalian likewise had come under Northwest Greek influence, though to

1900-448: Is considered by some linguists to have been closely related to Greek . Among Indo-European branches with living descendants, Greek is often argued to have the closest genetic ties with Armenian (see also Graeco-Armenian ) and Indo-Iranian languages (see Graeco-Aryan ). Ancient Greek differs from Proto-Indo-European (PIE) and other Indo-European languages in certain ways. In phonotactics , ancient Greek words could end only in

2000-719: Is distinguished from other parts of the Atlantic Ocean by its characteristic brown Sargassum seaweed and often calm blue water. The sea is bounded on the west by the Gulf Stream , on the north by the North Atlantic Current , on the east by the Canary Current , and on the south by the North Atlantic Equatorial Current , the four together forming a clockwise-circulating system of ocean currents termed

2100-626: Is due to the change in the regime of winds and currents: the North Atlantic gyre and the Equatorial counter current will push south along the northwest bulge of Africa, while the uncertain winds where the Northeast trades meet the Southeast trades (the doldrums) leave a sailing ship to the mercy of the currents. Together, prevalent current and wind make northwards progress very difficult or impossible. It

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2200-690: The Challenger expedition . Challenger , leased from the Royal Navy, was modified for scientific work and equipped with separate laboratories for natural history and chemistry . Under the scientific supervision of Thomson, Challenger travelled nearly 70,000 nautical miles (130,000 km) surveying and exploring. On her journey circumnavigating the globe, 492 deep sea soundings, 133 bottom dredges, 151 open water trawls and 263 serial water temperature observations were taken. Around 4,700 new species of marine life were discovered. The result

2300-652: The Australian Institute of Marine Science (AIMS), established in 1972 soon became a key player in marine tropical research. In 1921 the International Hydrographic Bureau , called since 1970 the International Hydrographic Organization , was established to develop hydrographic and nautical charting standards. Ancient Greek language Ancient Greek ( Ἑλληνῐκή , Hellēnikḗ ; [hellɛːnikɛ́ː] ) includes

2400-619: The European eel , the American eel , and the American conger eel. The larvae of these species hatch within the sea, and as they grow they travel to Europe or the East Coast of North America. Later in life, the matured eel migrates back to the Sargasso Sea to spawn and lay eggs . It is also believed that after hatching, young loggerhead sea turtles use currents such as the Gulf Stream to travel to

2500-745: The Greek region of Macedonia during the last decades has brought to light documents, among which the first texts written in Macedonian , such as the Pella curse tablet , as Hatzopoulos and other scholars note. Based on the conclusions drawn by several studies and findings such as Pella curse tablet , Emilio Crespo and other scholars suggest that ancient Macedonian was a Northwest Doric dialect , which shares isoglosses with its neighboring Thessalian dialects spoken in northeastern Thessaly . Some have also suggested an Aeolic Greek classification. The Lesbian dialect

2600-744: The Ishiguro Storm Surge Computer ) generally now replaced by numerical methods (e.g. SLOSH .) An oceanographic buoy array was established in the Pacific to allow prediction of El Niño events. 1990 saw the start of the World Ocean Circulation Experiment (WOCE) which continued until 2002. Geosat seafloor mapping data became available in 1995. Study of the oceans is critical to understanding shifts in Earth's energy balance along with related global and regional changes in climate ,

2700-1081: The Mediterranean Science Commission . Marine research institutes were already in existence, starting with the Stazione Zoologica Anton Dohrn in Naples, Italy (1872), the Biological Station of Roscoff, France (1876), the Arago Laboratory in Banyuls-sur-mer, France (1882), the Laboratory of the Marine Biological Association in Plymouth, UK (1884), the Norwegian Institute for Marine Research in Bergen, Norway (1900),

2800-460: The Mid-Atlantic Ridge . A 2011 report based the sea's boundaries on several variables including currents, presence of seaweed, and the topography of the ocean floor, and determined that the specific boundaries of the sea were "between 22°–38°N, 76°–43°W and centred on 30°N and 60°W" for a total of around 4,163,499 km (1,213,882 sq nmi). The Sargasso Sea is home to seaweed of

2900-471: The North Atlantic Gyre . It lies between 20° to 35° N and 40° and 70° W and is approximately 1,100 km (600 nmi) wide by 3,200 km (1,750 nmi) long. Bermuda is near the western fringes of the sea. Because the Sargasso Sea is bordered by oceanic currents, its precise borders may change. The Canary Current in particular is widely variable, and often the line utilized is one west of

3000-477: The North Atlantic Gyre . It lies between 20° and 35° north and 40° and 70° west and is approximately 1,100 kilometres (600 nautical miles) wide by 3,200 km (1,750 nmi) long. Bermuda is near the western fringes of the sea. While all of the above currents deposit marine plants and refuse into the sea, ocean water in the Sargasso Sea is distinctive for its deep blue color and exceptional clarity, with underwater visibility of up to 60 m (200 ft). It

3100-560: The biosphere and biogeochemistry . The atmosphere and ocean are linked because of evaporation and precipitation as well as thermal flux (and solar insolation ). Recent studies have advanced knowledge on ocean acidification , ocean heat content , ocean currents , sea level rise , the oceanic carbon cycle , the water cycle , Arctic sea ice decline , coral bleaching , marine heatwaves , extreme weather , coastal erosion and many other phenomena in regards to ongoing climate change and climate feedbacks . In general, understanding

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3200-501: The present , future , and imperfect are imperfective in aspect; the aorist , present perfect , pluperfect and future perfect are perfective in aspect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. The infinitives and participles correspond to the finite combinations of tense, aspect, and voice. The indicative of past tenses adds (conceptually, at least)

3300-404: The seas and oceans in pre-historic times. Observations on tides were recorded by Aristotle and Strabo in 384–322 BC. Early exploration of the oceans was primarily for cartography and mainly limited to its surfaces and of the animals that fishermen brought up in nets, though depth soundings by lead line were taken. The Portuguese campaign of Atlantic navigation is the earliest example of

3400-474: The 29 days Cabral took from Cape Verde up to landing in Monte Pascoal , Brazil. The Danish expedition to Arabia 1761–67 can be said to be the world's first oceanographic expedition, as the ship Grønland had on board a group of scientists, including naturalist Peter Forsskål , who was assigned an explicit task by the king, Frederik V , to study and describe the marine life in the open sea, including finding

3500-1031: The 5th century BC. Ancient pronunciation cannot be reconstructed with certainty, but Greek from the period is well documented, and there is little disagreement among linguists as to the general nature of the sounds that the letters represent. /oː/ raised to [uː] , probably by the 4th century BC. Greek, like all of the older Indo-European languages , is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In ancient Greek, nouns (including proper nouns) have five cases ( nominative , genitive , dative , accusative , and vocative ), three genders ( masculine , feminine , and neuter ), and three numbers (singular, dual , and plural ). Verbs have four moods ( indicative , imperative , subjunctive , and optative ) and three voices (active, middle, and passive ), as well as three persons (first, second, and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"):

3600-490: The Archaic period of ancient Greek (see Homeric Greek for more details): Μῆνιν ἄειδε, θεά, Πηληϊάδεω Ἀχιλῆος οὐλομένην, ἣ μυρί' Ἀχαιοῖς ἄλγε' ἔθηκε, πολλὰς δ' ἰφθίμους ψυχὰς Ἄϊδι προΐαψεν ἡρώων, αὐτοὺς δὲ ἑλώρια τεῦχε κύνεσσιν οἰωνοῖσί τε πᾶσι· Διὸς δ' ἐτελείετο βουλή· ἐξ οὗ δὴ τὰ πρῶτα διαστήτην ἐρίσαντε Ἀτρεΐδης τε ἄναξ ἀνδρῶν καὶ δῖος Ἀχιλλεύς. The beginning of Apology by Plato exemplifies Attic Greek from

3700-634: The Azores), bringing what is now Brazil into the Portuguese area of domination. The knowledge gathered from open sea exploration allowed for the well-documented extended periods of sail without sight of land, not by accident but as pre-determined planned route; for example, 30 days for Bartolomeu Dias culminating on Mossel Bay , the three months Gama spent in the South Atlantic to use the Brazil current (southward), or

3800-696: The Classical period of ancient Greek. (The second line is the IPA , the third is transliterated into the Latin alphabet using a modern version of the Erasmian scheme .) Ὅτι [hóti Hóti μὲν men mèn ὑμεῖς, hyːmêːs hūmeîs,   Sargasso Sea The Sargasso Sea ( / s ɑːr ˈ ɡ æ s oʊ / ) is a region of the Atlantic Ocean bounded by four currents forming an ocean gyre . Unlike all other regions called seas , it has no land boundaries. It

3900-577: The Gulf Stream's cause. Franklin and Timothy Folger printed the first map of the Gulf Stream in 1769–1770. Information on the currents of the Pacific Ocean was gathered by explorers of the late 18th century, including James Cook and Louis Antoine de Bougainville . James Rennell wrote the first scientific textbooks on oceanography, detailing the current flows of the Atlantic and Indian oceans. During

4000-766: The Laboratory für internationale Meeresforschung, Kiel, Germany (1902). On the other side of the Atlantic, the Scripps Institution of Oceanography was founded in 1903, followed by the Woods Hole Oceanographic Institution in 1930, the Virginia Institute of Marine Science in 1938, the Lamont–Doherty Earth Observatory at Columbia University in 1949, and later the School of Oceanography at University of Washington . In Australia ,

4100-410: The Sargasso Sea has negatively impacted it, such as over-fishing and shipping. The Sargasso Sea is often portrayed in literature and the media as an area of mystery. It is often depicted in fiction as a dangerous area where ships are mired in weed for centuries, unable to escape. Outer-space equivalents are a recurring motif in science fiction . Ezra Pound 's Portrait d'une Femme opens with

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4200-450: The Sargasso Sea, as did several other explorers. However, modern scholars consider this unlikely. In 1609, the English vessel Sea Venture was blown to the shore of Bermuda . The sea has also been the site of whaling and fishing. The 1920–1922 Dana expeditions , led by Johannes Schmidt , determined that the European eel 's breeding sites were in the Sargasso Sea. The sea has played

4300-435: The Sargasso Sea, where they use the sargassum as cover from predators until they are mature. The sargassum fish is a species of frogfish specially adapted to blend in among the sargassum seaweed. Millions of European eel babies are born there and then make an epic three-year journey back to UK waters ; many seabird species also fly and feed across that vast expanse of open golden sea on their way to Britain . In

4400-601: The Sargasso Sea. He had been competing in the Sunday Times Golden Globe Race , a single-handed , round-the-world yacht race when his poorly-prepared boat began to take on water. He abandoned his circumnavigation attempt, but reported false positions by radio in an attempt to give the impression that he was still participating. Eventually, Crowhurst wound up drifting in the Sargasso Sea, where he deteriorated psychologically, filling his logbooks with metaphysical speculation and delusional comments. His last entry

4500-518: The Sargasso accumulates a high concentration of non- biodegradable plastic waste. The area contains the huge North Atlantic garbage patch . Several nations and nongovernmental organizations have united to protect the Sargasso Sea. These organizations include the Sargasso Sea Commission established 11 March 2014 by the governments of the Azores (Portugal), Bermuda (United Kingdom), Monaco,

4600-450: The Seas describes the Sargasso Sea and gives an account of its formation. Thomas Allibone Janvier 's 1898 novel is titled In the Sargasso Sea . Uncharted Seas (1938) is a fantasy novel by Dennis Wheatley about a tramp steamer trapped in the Sargasso Sea surrounded by killer seaweed, murderous crustaceans, and previously marooned descendants of Spanish Conquistadores and pirates. This

4700-552: The Sun (the Sun just in a much lesser extent) and are also caused by the Earth and Moon orbiting each other. An ocean current is a continuous, directed movement of seawater generated by a number of forces acting upon the water, including wind, the Coriolis effect , breaking waves , cabbeling , and temperature and salinity differences . Sir James Clark Ross took the first modern sounding in deep sea in 1840, and Charles Darwin published

4800-527: The United Kingdom and the United States. Bacteria that consume plastic have been found in the plastic-polluted waters of the Sargasso Sea; however, it is unknown whether these bacteria ultimately clean up poisons or simply spread them elsewhere in the marine microbial ecosystem. Plastic debris can absorb toxic chemicals from ocean pollution , potentially poisoning anything that eats it. Human activity in

4900-550: The aorist. Following Homer 's practice, the augment is sometimes not made in poetry , especially epic poetry. The augment sometimes substitutes for reduplication; see below. Almost all forms of the perfect, pluperfect, and future perfect reduplicate the initial syllable of the verb stem. (A few irregular forms of perfect do not reduplicate, whereas a handful of irregular aorists reduplicate.) The three types of reduplication are: Irregular duplication can be understood diachronically. For example, lambanō (root lab ) has

5000-419: The augment when it was word-initial. In verbs with a preposition as a prefix, the augment is placed not at the start of the word, but between the preposition and the original verb. For example, προσ(-)βάλλω (I attack) goes to προσ έ βαλoν in the aorist. However compound verbs consisting of a prefix that is not a preposition retain the augment at the start of the word: αὐτο(-)μολῶ goes to ηὐ τομόλησα in

5100-596: The carbonate compensation depth will rise closer to the sea surface. Affected planktonic organisms will include pteropods , coccolithophorids and foraminifera , all important in the food chain . In tropical regions, corals are likely to be severely affected as they become less able to build their calcium carbonate skeletons, in turn adversely impacting other reef dwellers. The current rate of ocean chemistry change seems to be unprecedented in Earth's geological history, making it unclear how well marine ecosystems will adapt to

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5200-546: The cause of mareel , or milky seas. For this purpose, the expedition was equipped with nets and scrapers, specifically designed to collect samples from the open waters and the bottom at great depth. Although Juan Ponce de León in 1513 first identified the Gulf Stream , and the current was well known to mariners, Benjamin Franklin made the first scientific study of it and gave it its name. Franklin measured water temperatures during several Atlantic crossings and correctly explained

5300-438: The center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for the dialects is: West vs. non-West Greek is the strongest-marked and earliest division, with non-West in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Often non-West

5400-572: The centre for oceanographic research well into the 20th century. Murray was the first to study marine trenches and in particular the Mid-Atlantic Ridge , and map the sedimentary deposits in the oceans. He tried to map out the world's ocean currents based on salinity and temperature observations, and was the first to correctly understand the nature of coral reef development. In the late 19th century, other Western nations also sent out scientific expeditions (as did private individuals and institutions). The first purpose-built oceanographic ship, Albatros ,

5500-460: The context of the physical, chemical and geological characteristics of their ocean environment. Chemical oceanography is the study of the chemistry of the ocean. Whereas chemical oceanography is primarily occupied with the study and understanding of seawater properties and its changes, ocean chemistry focuses primarily on the geochemical cycles . The following is a central topic investigated by chemical oceanography. Ocean acidification describes

5600-502: The cosmographers would provide (...) and they took charts with exact routes and no longer those used by the ancient). His credibility rests on being personally involved in the instruction of pilots and senior seafarers from 1527 onwards by Royal appointment, along with his recognized competence as mathematician and astronomer. The main problem in navigating back from the south of the Canary Islands (or south of Boujdour ) by sail alone,

5700-533: The currents and winds of the Atlantic, is demonstrated by the understanding of the seasonal variations, with expeditions setting sail at different times of the year taking different routes to take account of seasonal predominate winds. This happens from as early as late 15th century and early 16th: Bartolomeu Dias followed the African coast on his way south in August 1487, while Vasco da Gama would take an open sea route from

5800-451: The decade long period between Bartolomeu Dias finding the southern tip of Africa, and Gama's departure; additionally, there are indications of further travels by Bartolomeu Dias in the area. The most significant consequence of this systematic knowledge was the negotiation of the Treaty of Tordesillas in 1494, moving the line of demarcation 270 leagues to the west (from 100 to 370 leagues west of

5900-405: The decrease in ocean pH that is caused by anthropogenic carbon dioxide (CO 2 ) emissions into the atmosphere . Seawater is slightly alkaline and had a preindustrial pH of about 8.2. More recently, anthropogenic activities have steadily increased the carbon dioxide content of the atmosphere; about 30–40% of the added CO 2 is absorbed by the oceans, forming carbonic acid and lowering

6000-611: The dialect of Sparta ), and Northern Peloponnesus Doric (including Corinthian ). All the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects. After the conquests of Alexander the Great in the late 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek , but with influence from other dialects. This dialect slowly replaced most of

6100-488: The early 2000s, the Sargasso Sea was sampled as part of the Global Ocean Sampling survey, to evaluate its diversity of microbial life through metagenomics . Contrary to previous theories, results indicated the area has a wide variety of prokaryotic life. Commonly called seaweed, Sargassum is a type of macroalgae. Like all algae, it produces oxygen. Based on 1975 measurements of oxygen production, and estimates of

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6200-406: The early ocean expeditions in oceanography, a major interest was the study of ocean currents and temperature measurements. The tides , the Coriolis effect , changes in direction and strength of wind , salinity, and temperature are the main factors determining ocean currents. The thermohaline circulation (THC) ( thermo- referring to temperature and -haline referring to salt content ) connects

6300-433: The first all-woman oceanographic expedition. Until that time, gender policies restricted women oceanographers from participating in voyages to a significant extent. From the 1970s, there has been much emphasis on the application of large scale computers to oceanography to allow numerical predictions of ocean conditions and as a part of overall environmental change prediction. Early techniques included analog computers (such as

6400-421: The first woman to have earned a PhD (at Scripps) in the United States, completed a major work on diatoms that remained the standard taxonomy in the field until well after her death in 1999. In 1940, Cupp was let go from her position at Scripps. Sverdrup specifically commended Cupp as a conscientious and industrious worker and commented that his decision was no reflection on her ability as a scientist. Sverdrup used

6500-563: The forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek ( c.  1400–1200 BC ), Dark Ages ( c.  1200–800 BC ), the Archaic or Epic period ( c.  800–500 BC ), and the Classical period ( c.  500–300 BC ). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers . It has contributed many words to English vocabulary and has been

6600-407: The genus Sargassum , which floats en masse on the surface. The Great Atlantic Sargassum Belt is the largest such mass in the world. The sargassum masses generally are not a threat to shipping, and historic incidents of sailing ships being trapped there are due to the often-calm winds of the horse latitudes . The Sargasso Sea plays a role in the migration of catadromous eel species such as

6700-506: The historical Dorians . The invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians. The Greeks of this period believed there were three major divisions of all Greek people – Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cypriot, far from

6800-424: The historical circumstances of the times imply that the overall groups already existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not later than 1120 BC, at the time of the Dorian invasions —and that their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to

6900-400: The instructor billet vacated by Cupp to employ Marston Sargent, a biologist studying marine algae, which was not a new research program at Scripps. Financial pressures did not prevent Sverdrup from retaining the services of two other young post-doctoral students, Walter Munk and Roger Revelle . Cupp's partner, Dorothy Rosenbury, found her a position teaching high school, where she remained for

7000-429: The latitude of Sierra Leone , spending three months in the open sea of the South Atlantic to profit from the southwards deflection of the southwesterly on the Brazilian side (and the Brazilian current going southward - Gama departed in July 1497); and Pedro Álvares Cabral (departing March 1500) took an even larger arch to the west, from the latitude of Cape Verde, thus avoiding the summer monsoon (which would have blocked

7100-490: The line: "Your mind and you are our Sargasso Sea", suggesting that the woman addressed in the poem is a repository of trivia and disconnected facts. The Sargasso Sea features in classic fantasy stories by William Hope Hodgson , such as his novel The Boats of the "Glen Carrig" (1907), Victor Appleton 's Don Sturdy novel Don Sturdy in the Port of Lost Ships: Or, Adrift in the Sargasso Sea , and several related short stories . Jules Verne 's Twenty Thousand Leagues Under

7200-725: The location of "islands" first identified by de Silves. Velho apparently got as far as the Formigas , in the eastern archipelago, before having to return to Sagres, probably due to bad weather. By this time, the Portuguese navigators had also reached the Sargasso Sea (western North Atlantic region), naming it after the Sargassum seaweed growing there ( sargaço / sargasso in Portuguese). Later in 1492, Christopher Columbus wrote about seaweed that he feared would trap his ship and potentially hide shallow waters that could run them aground, as well as

7300-508: The northern latitudes where the westerly winds will bring the seafarers towards the western coasts of Europe. The secrecy involving the Portuguese navigations, with the death penalty for the leaking of maps and routes, concentrated all sensitive records in the Royal Archives, completely destroyed by the Lisbon earthquake of 1775 . However, the systematic nature of the Portuguese campaign, mapping

7400-405: The ocean and across its boundaries; ecosystem dynamics; and plate tectonics and seabed geology. Oceanographers draw upon a wide range of disciplines to deepen their understanding of the world’s oceans, incorporating insights from astronomy , biology , chemistry , geography , geology , hydrology , meteorology and physics . Humans first acquired knowledge of the waves and currents of

7500-399: The ocean basins and is primarily dependent on the density of sea water . It is becoming more common to refer to this system as the 'meridional overturning circulation' because it more accurately accounts for other driving factors beyond temperature and salinity. Oceanic heat content (OHC) refers to the extra heat stored in the ocean from changes in Earth's energy balance . The increase in

7600-472: The ocean heat play an important role in sea level rise , because of thermal expansion . Ocean warming accounts for 90% of the energy accumulation associated with global warming since 1971. Paleoceanography is the study of the history of the oceans in the geologic past with regard to circulation, chemistry, biology, geology and patterns of sedimentation and biological productivity. Paleoceanographic studies using environment models and different proxies enable

7700-499: The older dialects, although the Doric dialect has survived in the Tsakonian language , which is spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek . By about the 6th century AD, the Koine had slowly metamorphosed into Medieval Greek . Phrygian is an extinct Indo-European language of West and Central Anatolia , which

7800-509: The pH (now below 8.1) through ocean acidification. The pH is expected to reach 7.7 by the year 2100. An important element for the skeletons of marine animals is calcium , but calcium carbonate becomes more soluble with pressure, so carbonate shells and skeletons dissolve below the carbonate compensation depth . Calcium carbonate becomes more soluble at lower pH, so ocean acidification is likely to affect marine organisms with calcareous shells, such as oysters, clams, sea urchins and corals, and

7900-487: The perfect stem eilēpha (not * lelēpha ) because it was originally slambanō , with perfect seslēpha , becoming eilēpha through compensatory lengthening. Reduplication is also visible in the present tense stems of certain verbs. These stems add a syllable consisting of the root's initial consonant followed by i . A nasal stop appears after the reduplication in some verbs. The earliest extant examples of ancient Greek writing ( c.  1450 BC ) are in

8000-521: The pirate Jolly Roger, Erik of Norway and Flavius from ancient Rome. They explain to Batman that a strange mist from the seaweed keeps them alive and ageless. Television "The Mystery of the Lizard Men" is the 1964 pilot episode of the animated series Jonny Quest . The story involves the disappearance of multiple ships in the Sargasso Sea and a secret laser base (protected by lizard-suited scuba divers) hidden aboard an 18th-century shipwreck. In

8100-689: The polar regions and Africa , so too did the mysteries of the unexplored oceans. The seminal event in the founding of the modern science of oceanography was the 1872–1876 Challenger expedition . As the first true oceanographic cruise, this expedition laid the groundwork for an entire academic and research discipline. In response to a recommendation from the Royal Society , the British Government announced in 1871 an expedition to explore world's oceans and conduct appropriate scientific investigation. Charles Wyville Thomson and Sir John Murray launched

8200-465: The rest of her career. (Russell, 2000) Sverdrup, Johnson and Fleming published The Oceans in 1942, which was a major landmark. The Sea (in three volumes, covering physical oceanography, seawater and geology) edited by M.N. Hill was published in 1962, while Rhodes Fairbridge 's Encyclopedia of Oceanography was published in 1966. The Great Global Rift, running along the Mid Atlantic Ridge,

8300-512: The return route from the western coast of Africa (sequentially called 'volta de Guiné' and 'volta da Mina'); and the references to the Sargasso Sea (also called at the time 'Mar da Baga'), to the west of the Azores , in 1436, reveals the western extent of the return route. This is necessary, under sail, to make use of the southeasterly and northeasterly winds away from the western coast of Africa, up to

8400-407: The route taken by Gama at the time he set sail). Furthermore, there were systematic expeditions pushing into the western Northern Atlantic (Teive, 1454; Vogado, 1462; Teles, 1474; Ulmo, 1486). The documents relating to the supplying of ships, and the ordering of sun declination tables for the southern Atlantic for as early as 1493–1496, all suggest a well-planned and systematic activity happening during

8500-601: The scientific community to assess the role of the oceanic processes in the global climate by the reconstruction of past climate at various intervals. Paleoceanographic research is also intimately tied to palaeoclimatology. The earliest international organizations of oceanography were founded at the turn of the 20th century, starting with the International Council for the Exploration of the Sea created in 1902, followed in 1919 by

8600-644: The shifting conditions of the near future. Of particular concern is the manner in which the combination of acidification with the expected additional stressors of higher ocean temperatures and lower oxygen levels will impact the seas. Geological oceanography is the study of the geology of the ocean floor including plate tectonics and paleoceanography . Physical oceanography studies the ocean's physical attributes including temperature-salinity structure, mixing, surface waves , internal waves, surface tides , internal tides , and currents . The following are central topics investigated by physical oceanography. Since

8700-477: The study of marine meteorology, navigation , and charting prevailing winds and currents. His 1855 textbook Physical Geography of the Sea was one of the first comprehensive oceanography studies. Many nations sent oceanographic observations to Maury at the Naval Observatory, where he and his colleagues evaluated the information and distributed the results worldwide. Knowledge of the oceans remained confined to

8800-520: The submersible DSV  Alvin . In the 1950s, Auguste Piccard invented the bathyscaphe and used the bathyscaphe Trieste to investigate the ocean's depths. The United States nuclear submarine Nautilus made the first journey under the ice to the North Pole in 1958. In 1962 the FLIP (Floating Instrument Platform), a 355-foot (108 m) spar buoy, was first deployed. In 1968, Tanya Atwater led

8900-517: The syllabic script Linear B . Beginning in the 8th century BC, however, the Greek alphabet became standard, albeit with some variation among dialects. Early texts are written in boustrophedon style, but left-to-right became standard during the classic period. Modern editions of ancient Greek texts are usually written with accents and breathing marks , interword spacing , modern punctuation , and sometimes mixed case , but these were all introduced later. The beginning of Homer 's Iliad exemplifies

9000-400: The topmost few fathoms of the water and a small amount of the bottom, mainly in shallow areas. Almost nothing was known of the ocean depths. The British Royal Navy 's efforts to chart all of the world's coastlines in the mid-19th century reinforced the vague idea that most of the ocean was very deep, although little more was known. As exploration ignited both popular and scientific interest in

9100-410: The total mass of Sargassum in the sea, it can be calculated that the Sargasso Sea may produce 2.2 billion litres of O₂ per hour, making the sea one of the primary sources of atmospheric oxygen. The Sargasso Sea, like many unique ocean ecosystems, is under various threats, such as industrial-scale fishing , plastic waste pollution , oil drilling , and deep-sea mining . Owing to surface currents,

9200-432: The world ocean through further scientific study enables better stewardship and sustainable utilization of Earth's resources. The Intergovernmental Oceanographic Commission reports that 1.7% of the total national research expenditure of its members is focused on ocean science. The study of oceanography is divided into these five branches: Biological oceanography investigates the ecology and biology of marine organisms in

9300-475: Was Aeolic. For example, fragments of the works of the poet Sappho from the island of Lesbos are in Aeolian. Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric ), Southern Peloponnesus Doric (including Laconian ,

9400-435: Was July 1, and his yacht was found unoccupied and drifting on July 10. It is unclear whether his death came as the result of suicide or misadventure . The sea is bounded on the west by the Gulf Stream , on the north by the North Atlantic Current , on the east by the Canary Current , and on the south by the North Atlantic Equatorial Current , the four together forming a clockwise-circulating system of ocean currents termed

9500-719: Was built in 1882. In 1893, Fridtjof Nansen allowed his ship, Fram , to be frozen in the Arctic ice. This enabled him to obtain oceanographic, meteorological and astronomical data at a stationary spot over an extended period. In 1881 the geographer John Francon Williams published a seminal book, Geography of the Oceans . Between 1907 and 1911 Otto Krümmel published the Handbuch der Ozeanographie , which became influential in awakening public interest in oceanography. The four-month 1910 North Atlantic expedition headed by John Murray and Johan Hjort

9600-586: Was discovered by Maurice Ewing and Bruce Heezen in 1953 and mapped by Heezen and Marie Tharp using bathymetric data; in 1954 a mountain range under the Arctic Ocean was found by the Arctic Institute of the USSR. The theory of seafloor spreading was developed in 1960 by Harry Hammond Hess . The Ocean Drilling Program started in 1966. Deep-sea vents were discovered in 1977 by Jack Corliss and Robert Ballard in

9700-586: Was made into an adventure film, The Lost Continent (1968), by Hammer Films and Seven Arts . Wide Sargasso Sea (1966) by Jean Rhys is inspired by Charlotte Brontë's Jane Eyre and gives Bertha Mason 's history, experiences and perspective. Two film adaptations of the same name have been released, one in 1993 and another in 2006 . "Prisoners of the Sargasso Sea" was a story published in Batman number 122 dated March 1959. Batman encounters ships trapped there for centuries. Batman and Robin are welcomed by

9800-600: Was the Report Of The Scientific Results of the Exploring Voyage of H.M.S. Challenger during the years 1873–76 . Murray, who supervised the publication, described the report as "the greatest advance in the knowledge of our planet since the celebrated discoveries of the fifteenth and sixteenth centuries". He went on to found the academic discipline of oceanography at the University of Edinburgh , which remained

9900-509: Was the most ambitious research oceanographic and marine zoological project ever mounted until then, and led to the classic 1912 book The Depths of the Ocean . The first acoustic measurement of sea depth was made in 1914. Between 1925 and 1927 the "Meteor" expedition gathered 70,000 ocean depth measurements using an echo sounder, surveying the Mid-Atlantic Ridge. In 1934, Easter Ellen Cupp ,

10000-471: Was to overcome this problem and clear the passage to India around Africa as a viable maritime trade route, that a systematic plan of exploration was devised by the Portuguese. The return route from regions south of the Canaries became the ' volta do largo' or 'volta do mar '. The 'rediscovery' of the Azores islands in 1427 is merely a reflection of the heightened strategic importance of the islands, now sitting on

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