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88-655: The AARI has numerous departments, such as those of oceanography , glaciology , meteorology , hydrology or Arctic river mouths and water resources, geophysics , polar geography, and others. It also has a computer center, ice research laboratory, experimental workshops, and a museum (the Arctic and Antarctic Museum ). Scientists, such as Alexander Karpinsky , Alexander Fersman , Yuly Shokalsky , Nikolai Knipovich , Lev Berg , Otto Schmidt , Rudolf Samoylovich , Vladimir Vize , Nikolai Zubov , Pyotr Shirshov , Nikolai Urvantsev , and Yakov Gakkel have all made contributions to

176-805: A CTD is used to measure electrical conductivity , temperature , and pressure , and is often mounted on a rosette of Nansen bottles to collect seawater for analysis. Sediments are commonly studied with a box corer or a sediment trap , and older sediments may be recovered by scientific drilling . Advanced analytical equipment such as mass spectrometers and chromatographs are applied to detect trace elements, isotopes, and organic compounds. This allows for precisely measuring nutrients, gases, and pollutants in marine environments. In recent years, autonomous underwater vehicles (AUVs) and remote sensing technology have enabled continuous, large-scale ocean chemistry monitoring, particularly for tracking changes in ocean acidification and nutrient cycles. The chemistry of

264-427: 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

352-408: A crucial role in understanding global biogeochemical cycles , ocean circulation , and the effects of human activities, such as pollution and climate change, on oceanic systems. It is influenced by plate tectonics and seafloor spreading , turbidity , currents , sediments , pH levels, atmospheric constituents, metamorphic activity, and ecology. The impact of human activity on the chemistry of

440-546: A new era. Researchers began using isotopic analysis to study ocean circulation and the carbon cycle. Roger Revelle and Hans Suess pioneered using radiocarbon dating to investigate oceanic carbon reservoirs and their exchange with the atmosphere. Since the 1970s, the development of highly sophisticated instruments and computational models has revolutionized marine chemistry. Scientists can now measure trace metals , organic compounds , and isotopic ratios with unprecedented precision. Studies of marine biogeochemical cycles, including

528-563: 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

616-489: A result, less oxygen is available for marine life. Early inquiries about marine chemistry usually concerned the origin of salinity in the ocean, including work by Robert Boyle . Modern chemical oceanography began as a field with the 1872–1876 Challenger expedition , led by the British Royal Navy which made the first systematic measurements of ocean chemistry. The chemical analysis of these samples providing

704-625: 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

792-424: 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 the seas and oceans in pre-historic times. Observations on tides were recorded by Aristotle and Strabo in 384–322 BC. Early exploration of

880-654: Is a global scale ion-exchange system. Hydrothermal vents at spreading centers introduce various amounts of iron , sulfur , manganese , silicon and other elements into the ocean, some of which are recycled into the ocean crust . Helium-3 , an isotope that accompanies volcanism from the mantle, is emitted by hydrothermal vents and can be detected in plumes within the ocean. Spreading rates on mid-ocean ridges vary between 10 and 200 mm/yr. Rapid spreading rates cause increased basalt reactions with seawater. The magnesium / calcium ratio will be lower because more magnesium ions are being removed from seawater and consumed by

968-651: 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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1056-717: Is likely to affect marine organisms with calcareous shells, such as oysters, clams, sea urchins and corals, and 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

1144-515: Is reduced, therefore adding further stress to marine organisms . The rising temperatures in the oceans also cause a reduced solubility of oxygen in the water, which can explain about 50% of oxygen loss in the upper level of the ocean (>1000 m). Warmer ocean water holds less oxygen and is more buoyant than cooler water. This leads to reduced mixing of oxygenated water near the surface with deeper water, which naturally contains less oxygen. Warmer water also raises oxygen demand from living organisms; as

1232-549: 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 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

1320-459: Is the most prolific source of halogenated organic compounds . POM includes of large organic particles, such as organisms, fecal pellets, and detritus, which settle through the water column. It is a major component of the biological pump, a process by which carbon is transferred from the surface ocean to the deep sea. As POM sinks, it decomposes by bacterial activity , releasing nutrients and carbon dioxide. The refractory POM fraction can settle on

1408-429: Is the reduction of the oxygen content in different parts of the ocean due to human activities. There are two areas where this occurs. Firstly, it occurs in coastal zones where eutrophication has driven some quite rapid (in a few decades) declines in oxygen to very low levels. This type of ocean deoxygenation is also called dead zones . Secondly, ocean deoxygenation occurs also in the open ocean. In that part of

1496-444: 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 the ocean and across its boundaries; ecosystem dynamics; and plate tectonics and seabed geology. Oceanographers draw upon

1584-407: Is the study of the chemical composition and processes of the world’s oceans, including the interactions between seawater, the atmosphere, the seafloor, and marine organisms. This field encompasses a wide range of topics, such as the cycling of elements like carbon, nitrogen, and phosphorus, the behavior of trace metals, and the study of gases and nutrients in marine environments. Marine chemistry plays

1672-511: Is very low and salinity is very high. Organisms trapped within freezing sea ice must adapt to a rapid change in salinity up to 3 times higher than that of regular seawater, as well as the rapid change to regular seawater salinity when ice melts. Most brine-pocket dwelling organisms are photosynthetic, therefore, these microenvironments can become hyperoxic, which can be toxic to its inhabitants. Thus, these extremophiles often produce high levels of antioxidants. Seafloor spreading on mid-ocean ridges

1760-705: 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

1848-683: 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. Chemical oceanography Marine chemistry , also known as ocean chemistry or chemical oceanography ,

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1936-704: The Council of Ministers of the USSR (now Federal Service for Hydrometeorology and Environmental Monitoring of Russia ). In 1967, AARI was awarded the Order of Lenin . 59°56′47.5″N 30°14′0″E  /  59.946528°N 30.23333°E  / 59.946528; 30.23333 Oceanography Oceanography (from Ancient Greek ὠκεανός ( ōkeanós )  ' ocean ' and γραφή ( graphḗ )  ' writing '), also known as oceanology , sea science , ocean science , and marine science ,

2024-779: 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 ,

2112-1169: 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),

2200-585: The atmosphere is absorbed by the oceans. This chemical reaction produces carbonic acid ( H 2 CO 3 ) which dissociates into a bicarbonate ion ( HCO − 3 ) and a hydrogen ion ( H ). The presence of free hydrogen ions ( H ) lowers the pH of the ocean, increasing acidity (this does not mean that seawater is acidic yet; it is still alkaline , with a pH higher than 8). Marine calcifying organisms , such as mollusks and corals , are especially vulnerable because they rely on calcium carbonate to build shells and skeletons. Ocean deoxygenation

2288-560: 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

2376-517: The carbon , nitrogen , and sulfur cycles , have become an area of interest to understand global climate change . The use of remote sensing technology and global ocean observation programs, such as the International Geosphere-Biosphere Programme (IGBP), has provided large-scale data on ocean chemistry, allowing scientists to monitor ocean acidification , deoxygenation , and other critical issues affecting

2464-416: The ecology of marine environments . Ocean acidification is the ongoing decrease in the pH of the Earth's ocean . Between 1950 and 2020, the average pH of the ocean surface fell from approximately 8.15 to 8.05. Carbon dioxide emissions from human activities are the primary cause of ocean acidification, with atmospheric carbon dioxide (CO 2 ) levels exceeding 422 ppm (as of 2024 ). CO 2 from

2552-469: The ocean and cause harmful effects there. The majority of this waste (80%) comes from land-based activity, although marine transportation significantly contributes as well. It is a combination of chemicals and trash, most of which comes from land sources and is washed or blown into the ocean. This pollution results in damage to the environment, to the health of all organisms, and to economic structures worldwide. Since most inputs come from land, either via

2640-444: The rivers , sewage or the atmosphere, it means that continental shelves are more vulnerable to pollution. Air pollution is also a contributing factor by carrying off iron, carbonic acid, nitrogen , silicon, sulfur, pesticides or dust particles into the ocean. The pollution often comes from nonpoint sources such as agricultural runoff , wind-blown debris , and dust. These nonpoint sources are largely due to runoff that enters

2728-481: 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

Arctic and Antarctic Research Institute - Misplaced Pages Continue

2816-795: The AARI participated in the organization of Antarctic research. In 1958, it began to organize and lead all of the Soviet Antarctic expeditions, which would later make geographic discoveries, and in the same year the All-Union Arctic Institute was renamed Arctic and Antarctic Research Institute . In 1963, the AARI was incorporated into the Chief Administration of the Hydrometeorological Service (Главное управление Гидрометеослужбы) under

2904-655: 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

2992-490: The Earth's oceans has increased over time, with pollution from industry and various land-use practices significantly affecting the oceans. Moreover, increasing levels of carbon dioxide in the Earth's atmosphere have led to ocean acidification , which has negative effects on marine ecosystems. The international community has agreed that restoring the chemistry of the oceans is a priority, and efforts toward this goal are tracked as part of Sustainable Development Goal 14 . Due to

3080-656: 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

3168-857: 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 ,

3256-586: The Mg/Ca ratio in an organism's skeleton varies with the Mg/Ca ratio of the seawater in which it was grown. The mineralogy of reef-building and sediment-producing organisms is thus regulated by chemical reactions occurring along the mid-ocean ridge, the rate of which is controlled by the rate of sea-floor spreading. Marine pollution occurs when substances used or spread by humans, such as industrial , agricultural and residential waste , particles , noise , excess carbon dioxide or invasive organisms enter

3344-561: 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

3432-411: The basis of unique ecosystems. Several different metabolisms are present in hydrothermal vent ecosystems. Many marine microorganisms, including Thiomicrospira , Halothiobacillus , and Beggiatoa , are capable of oxidizing sulfur compounds, including elemental sulfur and the often toxic compound H 2 S. H 2 S is abundant in hydrothermal vents, formed through interactions between seawater and rock at

3520-552: 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

3608-641: 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 ,

Arctic and Antarctic Research Institute - Misplaced Pages Continue

3696-460: 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

3784-511: 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,

3872-542: 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

3960-456: 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

4048-406: 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

4136-567: The extra heat stored in the ocean from changes in Earth's energy balance . The increase in 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

4224-433: 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

4312-597: The first systematic study of the composition of seawater was conducted by John Murray and George Forchhammer, leading to a better understanding of elements like chloride, sodium, and sulfate in ocean waters The early 20th century saw significant advancements in marine chemistry, particularly with more accurate analytical techniques. Scientists like Martin Knudsen created the Knudsen Bottle, an instrument used to collect water samples from different ocean depths. Over

4400-485: 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

4488-666: The high temperatures found within vents. This compound is a major energy source, forming the basis of the sulfur cycle in hydrothermal vent ecosystems. In the colder waters surrounding vents, sulfur-oxidation can occur using oxygen as an electron acceptor ; closer to the vents, organisms must use alternate metabolic pathways or utilize another electron acceptor, such as nitrate. Some species of Thiomicrospira can utilize thiosulfate as an electron donor, producing elemental sulfur. Additionally, many marine microorganisms are capable of iron-oxidation, such as Mariprofundus ferrooxydans . Iron-oxidation can be oxic, occurring in oxygen-rich parts of

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4576-767: The institute was integrated into the Chief Directorate of the Northern Sea Route (Главное управление Северного морского пути). In 1948 the Arctic Geology Research Institute (Научно-исследовательский институт геологии Арктики, or НИИГА) was established on the basis of the geology department of the All-Union Arctic Institute, which would subordinate to the Ministry of Geology of the USSR . In 1955,

4664-400: 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

4752-475: The interrelatedness of the ocean, chemical oceanographers frequently work on problems relevant to physical oceanography , geology and geochemistry , biology and biochemistry , and atmospheric science . Many of them are investigating biogeochemical cycles , and the marine carbon cycle in particular attracts significant interest due to its role in carbon sequestration and ocean acidification . Other major topics of interest include analytical chemistry of

4840-537: 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

4928-478: The main factors determining ocean currents. The thermohaline circulation (THC) ( thermo- referring to temperature and -haline referring to salt content ) connects 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

5016-435: The marine environment. Chemical oceanographers collect and measure chemicals in seawater, using the standard toolset of analytical chemistry as well as instruments like pH meters , electrical conductivity meters , fluorometers , and dissolved CO₂ meters. Most data are collected through shipboard measurements and from autonomous floats or buoys , but remote sensing is used as well. On an oceanographic research vessel ,

5104-520: 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

5192-432: The ocean is, how nutrients and carbon move around , and how marine habitats function. As the oceans become warmer this increases the loss of oxygen in the oceans. This is because the warmer temperatures increase ocean stratification . The reason for this lies in the multiple connections between density and solubility effects that result from warming. As a side effect, the availability of nutrients for marine life

5280-532: The ocean floor and make relevant contributions to carbon sequestration over a very long period of time The ocean is home to a variety of marine organisms known as extremophiles – organisms that thrive in extreme conditions of temperature, pressure, and light availability. Extremophiles inhabit many unique habitats in the ocean, such as hydrothermal vents , black smokers, cold seeps , hypersaline regions, and sea ice brine pockets . Some scientists have speculated that life may have evolved from hydrothermal vents in

5368-477: The ocean through rivers, but wind-blown debris and dust can also play a role, as these pollutants can settle into waterways and oceans. Pathways of pollution include direct discharge, land runoff, ship pollution , bilge pollution , atmospheric pollution and, potentially, deep sea mining . Increased carbon dioxide levels, mostly from burning fossil fuels , are changing ocean chemistry. Global warming and changes in salinity have significant implications for

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5456-480: 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 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

5544-428: The ocean, or anoxic, requiring either an electron acceptor such as nitrate or light energy. In iron-oxidation, Fe(II) is used as an electron donor ; conversely, iron-reducers utilize Fe(III) as an electron acceptor. These two metabolisms form the basis of the iron-redox cycle and may have contributed to banded iron formations . At another extreme, some marine extremophiles inhabit sea ice brine pockets where temperature

5632-496: The ocean, there is nowadays an ongoing reduction in oxygen levels. As a result, the naturally occurring low oxygen areas (so called oxygen minimum zones (OMZs)) are now expanding slowly. This expansion is happening as a consequence of human caused climate change . The resulting decrease in oxygen content of the oceans poses a threat to marine life , as well as to people who depend on marine life for nutrition or livelihood. A decrease in ocean oxygen levels affects how productive

5720-533: The ocean. In hydrothermal vents and similar environments, many extremophiles acquire energy through chemoautotrophy , using chemical compounds as energy sources, rather than light as in photoautotrophy . Hydrothermal vents enrich the nearby environment in chemicals such as elemental sulfur , H 2 , H 2 S , Fe , and methane . Chemoautotrophic organisms, primarily prokaryotes, derive energy from these chemicals through redox reactions . These organisms then serve as food sources for higher trophic levels , forming

5808-412: 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 a systematic scientific large project, sustained over many decades, studying the currents and winds of the Atlantic. The work of Pedro Nunes (1502–1578)

5896-428: The oceans, marine pollution , and anthropogenic climate change . DOM is a critical component of the ocean's carbon pool and includes many molecules such as amino acids, sugars, and lipids. It represents about 90% of the total organic carbon in marine environments. Colored dissolved organic matter (CDOM) is estimated to range from 20-70% of the carbon content of the oceans, being higher near river outlets and lower in

5984-430: The open ocean. DOM can be recycled and put back into the food web through a process called microbial loop which is essential for nutrient cycling and supporting primary productivity. It also plays a vital role in the global regulation of oceanic carbon storage, as some forms resist microbial degradation and may exist within the ocean for centuries. Marine life is similar mainly in biochemistry to terrestrial organisms, and

6072-402: 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

6160-534: The past three decades (1970s, 19802, and 1990s), a comprehensive evaluation of advancements in chemical oceanography was compiled through a National Science Foundation initiative known as Futures of Ocean Chemistry in the United States (FOCUS). This project brought together numerous prominent chemical oceanographers, marine chemists, and geochemists to contribute to the FOCUS report. After World War II, advancements in geochemical techniques propelled marine chemistry into

6248-705: 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

6336-474: 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,

6424-523: 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

6512-624: The rock, and more calcium ions are being removed from the rock and released to seawater. Hydrothermal activity at ridge crest is efficient in removing magnesium. A lower Mg/Ca ratio favors the precipitation of low-Mg calcite polymorphs of calcium carbonate ( calcite seas ). Slow spreading at mid-ocean ridges has the opposite effect and will result in a higher Mg/Ca ratio favoring the precipitation of aragonite and high-Mg calcite polymorphs of calcium carbonate ( aragonite seas ). Experiments show that most modern high-Mg calcite organisms would have been low-Mg calcite in past calcite seas, meaning that

6600-410: 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

6688-619: 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

6776-400: 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

6864-486: 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

6952-530: 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

7040-400: 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

7128-507: The work of the AARI. Throughout its history, the AARI has organized more than a thousand Arctic expeditions, including dozens of high-latitude aerial expeditions, which transported 34(?) manned drifting ice stations Severniy Polyus ("Северный полюс", or North Pole) to Central Arctic. In 2019-2020 Arctic and Antarctic Research Institute joined a biggest in history Arctic expedition MOSAiC , where its scientists were primarily involved in measurements of sea ice mechanics and seismics. The AARI

7216-434: 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

7304-736: 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

7392-553: 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

7480-751: Was founded on 3 March 1920 as the Northern Research and Trade Expedition (Северная научно-промысловая экспедиция) under the Scientific and Technical Department of the All-Union Council of State Economy . In 1925, the expedition was reorganized into the Institute of Northern Studies (Институт по изучению Севера) and five years later - into the All-Union Arctic Institute (Всесоюзный арктический институт). In 1932,

7568-627: 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

7656-521: 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 ,

7744-476: 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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