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93-576: The Barents Sea is a rather shallow shelf sea with an average depth of 230 metres (750 ft), and it is an important site for both fishing and hydrocarbon exploration . It is bordered by the Kola Peninsula to the south, the shelf edge towards the Norwegian Sea to the west, the archipelagos of Svalbard to the northwest, Franz Josef Land to the northeast and Novaya Zemlya to the east. The islands of Novaya Zemlya, an extension of

186-677: A 2019 paper holds BKS ice decline responsible for 44% of the 1995–2014 central Eurasian cooling trend, far more than indicated by the models, while another study from that year suggests that the decline in BKS ice reduces snow cover in the North Eurasia but increases it in central Europe. There are also potential links to summer precipitation: a connection has been proposed between the reduced BKS ice extent in November–December and greater June rainfall over South China . One paper even identified

279-508: A better view of their global distribution. The term phytoplankton encompasses all photoautotrophic microorganisms in aquatic food webs . However, unlike terrestrial communities , where most autotrophs are plants , phytoplankton are a diverse group, incorporating protistan eukaryotes and both eubacterial and archaebacterial prokaryotes . There are about 5,000 known species of marine phytoplankton. How such diversity evolved despite scarce resources (restricting niche differentiation )

372-435: A body of water or cultured, though the former method is seldom used. Phytoplankton is used as a foodstock for the production of rotifers , which are in turn used to feed other organisms. Phytoplankton is also used to feed many varieties of aquacultured molluscs , including pearl oysters and giant clams . A 2018 study estimated the nutritional value of natural phytoplankton in terms of carbohydrate, protein and lipid across

465-583: A calcium carbonate shell called a coccosphere that is sensitive to ocean acidification. Because of their short generation times, evidence suggests some phytoplankton can adapt to changes in pH induced by increased carbon dioxide on rapid time-scales (months to years). Phytoplankton serve as the base of the aquatic food web, providing an essential ecological function for all aquatic life. Under future conditions of anthropogenic warming and ocean acidification, changes in phytoplankton mortality due to changes in rates of zooplankton grazing may be significant. One of

558-519: A connection between Kara Sea ice extent and the ice cover of Lake Qinghai on the Tibetan Plateau . The Barents Sea was formerly known to Russians as Murmanskoye More , or the "Sea of Murmans" (i.e., their term for Norwegians). It appears with this name in sixteenth-century maps, including Gerard Mercator 's Map of the Arctic published in his 1595 atlas. Its eastern corner, in the region of

651-455: A continental shelf differs significantly from the geological definition. UNCLOS states that the shelf extends to the limit of the continental margin , but no less than 200 nmi (370 km; 230 mi) and no more than 350 nmi (650 km; 400 mi) from the baseline . Thus inhabited volcanic islands such as the Canaries , which have no actual continental shelf, nonetheless have

744-525: A culture medium. This water must be sterilized , usually by either high temperatures in an autoclave or by exposure to ultraviolet radiation , to prevent biological contamination of the culture. Various fertilizers are added to the culture medium to facilitate the growth of plankton. A culture must be aerated or agitated in some way to keep plankton suspended, as well as to provide dissolved carbon dioxide for photosynthesis . In addition to constant aeration, most cultures are manually mixed or stirred on

837-832: A distance where the depth of waters admitted of resource exploitation were claimed by the marine nations that signed the Convention on the Continental Shelf drawn up by the UN's International Law Commission in 1958. This was partly superseded by the 1982 United Nations Convention on the Law of the Sea (UNCLOS). The 1982 convention created the 200 nautical miles (370 km; 230 mi) exclusive economic zone, plus continental shelf rights for states with physical continental shelves that extend beyond that distance. The legal definition of

930-464: A few exceptions, the shelf break is located at a remarkably uniform depth of roughly 140 m (460 ft); this is likely a hallmark of past ice ages, when sea level was lower than it is now. The continental slope is much steeper than the shelf; the average angle is 3°, but it can be as low as 1° or as high as 10°. The slope is often cut with submarine canyons . The physical mechanisms involved in forming these canyons were not well understood until

1023-783: A fundamental principle to understand marine ecology, biogeochemistry and phytoplankton evolution. However, the Redfield ratio is not a universal value and it may diverge due to the changes in exogenous nutrient delivery and microbial metabolisms in the ocean, such as nitrogen fixation , denitrification and anammox . The dynamic stoichiometry shown in unicellular algae reflects their capability to store nutrients in an internal pool, shift between enzymes with various nutrient requirements and alter osmolyte composition. Different cellular components have their own unique stoichiometry characteristics, for instance, resource (light or nutrients) acquisition machinery such as proteins and chlorophyll contain

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1116-495: A high concentration of nitrogen but low in phosphorus. Meanwhile, growth machinery such as ribosomal RNA contains high nitrogen and phosphorus concentrations. Based on allocation of resources, phytoplankton is classified into three different growth strategies, namely survivalist, bloomer and generalist. Survivalist phytoplankton has a high ratio of N:P (>30) and contains an abundance of resource-acquisition machinery to sustain growth under scarce resources. Bloomer phytoplankton has

1209-646: A legal continental shelf, whereas uninhabitable islands have no shelf. Phytoplankton Phytoplankton ( / ˌ f aɪ t oʊ ˈ p l æ ŋ k t ə n / ) are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems . The name comes from the Greek words φυτόν ( phyton ), meaning ' plant ', and πλαγκτός ( planktos ), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis , as trees and other plants do on land. This means phytoplankton must have light from

1302-565: A low N:P ratio (<10), contains a high proportion of growth machinery, and is adapted to exponential growth. Generalist phytoplankton has similar N:P to the Redfield ratio and contain relatively equal resource-acquisition and growth machinery. The NAAMES study was a five-year scientific research program conducted between 2015 and 2019 by scientists from Oregon State University and NASA to investigated aspects of phytoplankton dynamics in ocean ecosystems, and how such dynamics influence atmospheric aerosols , clouds, and climate (NAAMES stands for

1395-435: A nutritional supplement for captive invertebrates in aquaria . Culture sizes range from small-scale laboratory cultures of less than 1L to several tens of thousands of litres for commercial aquaculture. Regardless of the size of the culture, certain conditions must be provided for efficient growth of plankton. The majority of cultured plankton is marine, and seawater of a specific gravity of 1.010 to 1.026 may be used as

1488-491: A regular basis. Light must be provided for the growth of phytoplankton. The colour temperature of illumination should be approximately 6,500 K, but values from 4,000 K to upwards of 20,000 K have been used successfully. The duration of light exposure should be approximately 16 hours daily; this is the most efficient artificial day length. Marine phytoplankton perform half of the global photosynthetic CO 2 fixation (net global primary production of ~50 Pg C per year) and half of

1581-493: A species increases rapidly under conditions favorable to growth can produce harmful algal blooms (HABs). Phytoplankton are a key food item in both aquaculture and mariculture . Both utilize phytoplankton as food for the animals being farmed. In mariculture, the phytoplankton is naturally occurring and is introduced into enclosures with the normal circulation of seawater. In aquaculture, phytoplankton must be obtained and introduced directly. The plankton can either be collected from

1674-466: A succession of dry holes, wells containing only gas (which was cheap at the time), and the prohibitive costs of developing wells in such a remote area. Interest in the area was reignited in the late 2000s after the Snovhit field was finally brought into production and two new large discoveries were made. The Russians began exploration in their territory around the same time, encouraged by their success in

1767-465: Is a notable exception). While almost all phytoplankton species are obligate photoautotrophs , there are some that are mixotrophic and other, non-pigmented species that are actually heterotrophic (the latter are often viewed as zooplankton ). Of these, the best known are dinoflagellate genera such as Noctiluca and Dinophysis , that obtain organic carbon by ingesting other organisms or detrital material. Phytoplankton live in

1860-399: Is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea . Much of these shelves were exposed by drops in sea level during glacial periods . The shelf surrounding an island is known as an insular shelf . The continental margin , between the continental shelf and the abyssal plain , comprises a steep continental slope, surrounded by

1953-604: Is an environmental concern in the Barents Sea. For decades there was a boundary dispute between Norway and Russia regarding the position of the boundary between their respective claims to the Barents Sea. The Norwegians favoured a median line , based on the Geneva Convention of 1958 , whereas the Russians favoured a meridian - based sector line, based on a Soviet decision of 1926. A neutral "grey" zone between

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2046-500: Is declining, leading to higher light penetration and potentially more primary production; however, there are conflicting predictions for the effects of variable mixing patterns and changes in nutrient supply and for productivity trends in polar zones. The effect of human-caused climate change on phytoplankton biodiversity is not well understood. Should greenhouse gas emissions continue rising to high levels by 2100, some phytoplankton models predict an increase in species richness , or

2139-497: Is driven by — the Redfield ratio of macronutrients generally available throughout the surface oceans. Phytoplankton also rely on trace metals such as iron (Fe), manganese (Mn), zinc (Zn), cobalt (Co), cadmium (Cd) and copper (Cu) as essential micronutrients, influencing their growth and community composition. Limitations in these metals can lead to co-limitations and shifts in phytoplankton community structure. Across large areas of

2232-889: Is evaluating the contributions of phytoplankton to carbon fixation and forecasting how this production may change in response to perturbations. Predicting the effects of climate change on primary productivity is complicated by phytoplankton bloom cycles that are affected by both bottom-up control (for example, availability of essential nutrients and vertical mixing) and top-down control (for example, grazing and viruses). Increases in solar radiation, temperature and freshwater inputs to surface waters strengthen ocean stratification and consequently reduce transport of nutrients from deep water to surface waters, which reduces primary productivity. Conversely, rising CO 2 levels can increase phytoplankton primary production, but only when nutrients are not limiting. Some studies indicate that overall global oceanic phytoplankton density has decreased in

2325-469: Is evidence that changing wind, rainfall, and regional ocean currents in a warming ocean are having an effect on some shelf seas. Improved data collection via Integrated Ocean Observing Systems in shelf sea regions is making identification of these changes possible. Continental shelves teem with life because of the sunlight available in shallow waters, in contrast to the biotic desert of the oceans' abyssal plain . The pelagic (water column) environment of

2418-425: Is of utmost importance to secondary producers such as copepods, fish and shrimp, because it determines the nutritional quality and influences energy flow through the marine food chains . Climate change may greatly restructure phytoplankton communities leading to cascading consequences for marine food webs , thereby altering the amount of carbon transported to the ocean interior. The figure gives an overview of

2511-447: Is predicted to co-occur with ocean acidification and warming, due to increased stratification of the water column and reduced mixing of nutrients from the deep water to the surface. The compartments influenced by phytoplankton include the atmospheric gas composition, inorganic nutrients, and trace element fluxes as well as the transfer and cycling of organic matter via biological processes (see figure). The photosynthetically fixed carbon

2604-451: Is rapidly recycled and reused in the surface ocean, while a certain fraction of this biomass is exported as sinking particles to the deep ocean, where it is subject to ongoing transformation processes, e.g., remineralization. Phytoplankton contribute to not only a basic pelagic marine food web but also to the microbial loop. Phytoplankton are the base of the marine food web and because they do not rely on other organisms for food, they make up

2697-471: Is unclear. In terms of numbers, the most important groups of phytoplankton include the diatoms , cyanobacteria and dinoflagellates , although many other groups of algae are represented. One group, the coccolithophorids , is responsible (in part) for the release of significant amounts of dimethyl sulfide (DMS) into the atmosphere . DMS is oxidized to form sulfate which, in areas where ambient aerosol particle concentrations are low, can contribute to

2790-629: The North Atlantic drift ; cold Arctic water (temperature <0 °C, salinity <35) from the north; and warm, but not very salty, coastal water (temperature >3 °C, salinity <34.7). Between the Atlantic and Polar waters, a front called the Polar Front is formed. In the western parts of the sea (close to Bear Island ), this front is determined by the bottom topography and is therefore relatively sharp and stable from year to year, while in

2883-698: The Pechora River 's estuary, has been known as Pechorskoye Morye , that is, Pechora Sea . It was also known as Pomorsky Morye , after the first inhabitants of its shores, the Pomors . This sea was given its present name by Europeans in honour of Willem Barentsz , a Dutch navigator and explorer. Barentsz was the leader of early expeditions to the far north, at the end of the sixteenth century. The Barents Sea has been called by sailors " The Devil's Dance Floor " due to its unpredictability and difficulty level. Ocean rowers call it " Devil's Jaw ". In 2017, after

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2976-482: The Persian Gulf . The average width of continental shelves is about 80 km (50 mi). The depth of the shelf also varies, but is generally limited to water shallower than 100 m (330 ft). The slope of the shelf is usually quite low, on the order of 0.5°; vertical relief is also minimal, at less than 20 m (66 ft). Though the continental shelf is treated as a physiographic province of

3069-549: The Timan-Pechora Basin . They drilled their first wells in the early 1980s, and some very large gas fields were discovered throughout this decade. The Shtokman field was discovered in 1988 and is classed as a giant gas field: currently the 5th-largest gas field in the world . Similar practical difficulties Barents Sea resulted in a decline in Russian exploration, aggravated by the nation's political instability of

3162-449: The diatoms ). Most phytoplankton are too small to be individually seen with the unaided eye . However, when present in high enough numbers, some varieties may be noticeable as colored patches on the water surface due to the presence of chlorophyll within their cells and accessory pigments (such as phycobiliproteins or xanthophylls ) in some species. Phytoplankton are photosynthesizing microscopic protists and bacteria that inhabit

3255-422: The diatoms ). Many other organism groups formally named as phytoplankton, including coccolithophores and dinoflagellates , are now no longer included as they are not only phototrophic but can also eat. These organisms are now more correctly termed  mixoplankton . This recognition has important consequences for how we view the functioning of the planktonic food web. Phytoplankton obtain energy through

3348-463: The ocean , it is not part of the deep ocean basin proper, but the flooded margins of the continent. Passive continental margins such as most of the Atlantic coasts have wide and shallow shelves, made of thick sedimentary wedges derived from long erosion of a neighboring continent. Active continental margins have narrow, relatively steep shelves, due to frequent earthquakes that move sediment to

3441-449: The photic zone of the ocean, where photosynthesis is possible. During photosynthesis, they assimilate carbon dioxide and release oxygen. If solar radiation is too high, phytoplankton may fall victim to photodegradation . Phytoplankton species feature a large variety of photosynthetic pigments which species-specifically enables them to absorb different wavelengths of the variable underwater light. This implies different species can use

3534-433: The process of photosynthesis and must therefore live in the well-lit surface layer (termed the euphotic zone ) of an ocean , sea , lake , or other body of water. Phytoplankton account for about half of all photosynthetic activity on Earth. Their cumulative energy fixation in carbon compounds ( primary production ) is the basis for the vast majority of oceanic and also many freshwater food webs ( chemosynthesis

3627-414: The 1960s. Continental shelves cover an area of about 27 million km (10 million sq mi), equal to about 7% of the surface area of the oceans. The width of the continental shelf varies considerably—it is not uncommon for an area to have virtually no shelf at all, particularly where the forward edge of an advancing oceanic plate dives beneath continental crust in an offshore subduction zone such as off

3720-593: The 1990s. The Barents Sea contains the world's largest remaining cod population, as well as important stocks of haddock and capelin. Fishing is managed jointly by Russia and Norway in the form of the Joint Norwegian–Russian Fisheries Commission , established in 1976, in an attempt to keep track of how many fish are leaving the ecosystem due to fishing. The Joint Norwegian-Russian Fisheries Commission sets Total Allowable Catches (TACs) for multiple species throughout their migratory tracks. Through

3813-408: The Arctic, there are concerns that a further increase in pollution is likely, not least from the increased risk of future oil spills from ships not properly equipped for the environment. Barents Sea is the fastest-warming part of the Arctic, and some assessments now treat Barents sea ice as a separate tipping point from the rest of the Arctic sea ice, suggesting that it could permanently disappear once

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3906-633: The Commission, Norway and Russia also exchange fishing quotas and catch statistics to ensure the TACs are not being violated. However there are problems with reporting under this system, and researchers believe that they do not have accurate data for the effects of fishing on the Barents Sea ecosystem. Cod is one of the major catches. A large portion of catches are not reported when the fishing boats land, to account for profits that are being lost to high taxes and fees. Since many fishermen do not strictly follow

3999-667: The German cruiser Admiral Hipper was severely damaged by British gunfire. The Germans later retreated and the British convoy arrived safely at Murmansk shortly afterwards. During the Cold War , the Soviet Red Banner Northern Fleet used the southern reaches of the sea as a ballistic missile submarine bastion , a strategy that Russia continued. Nuclear contamination from dumped Russian naval reactors

4092-625: The North Atlantic Aerosols and Marine Ecosystems Study). The study focused on the sub-arctic region of the North Atlantic Ocean, which is the site of one of Earth's largest recurring phytoplankton blooms. The long history of research in this location, as well as relative ease of accessibility, made the North Atlantic an ideal location to test prevailing scientific hypotheses in an effort to better understand

4185-531: The TACs and rules set forth by the Commission, the amount of fish being extracted annually from the Barents Sea is underestimated. The Barents Sea, where temperate waters from the Gulf Stream and cold waters from the Arctic meet, is home to an enormous diversity of organisms, which are well-adapted to the extreme conditions of their marine habitats. This makes these arctic species very attractive for marine bioprospecting . Marine bioprospecting may be defined as

4278-404: The base of marine and freshwater food webs and are key players in the global carbon cycle . They account for about half of global photosynthetic activity and at least half of the oxygen production, despite amounting to only about 1% of the global plant biomass. Phytoplankton are very diverse, comprising photosynthesizing bacteria ( cyanobacteria ) and various unicellular protist groups (notably

4371-484: The boundary equidistant from their competing claims. This was ratified and went into force on 7 July 2011, opening the grey zone for hydrocarbon exploration . Encouraged by the success of oil exploration and production in the North Sea in the 1960s , Norway began hydrocarbon exploration in the Barents Sea in 1969. They acquired seismic reflection surveys through the following years, which were analysed to understand

4464-688: The cause of depleting fish stocks, more recent research suggests that marine mammal consumption has only a trivial influence on fisheries. A model assessing the effects of fisheries and climate was far more accurate at describing trends in fish abundance. There is a genetically distinct polar bear population associated with the Barents Sea. The Barents Sea is "among the most polluted places on Earth" due to accumulated marine garbage, decades of Soviet nuclear tests, radioactive waste dumping and industrial pollution. The elevated pollution has caused elevated rates of disease among locals. With rising military buildup and increased use of shipping lanes heading east through

4557-650: The coast of Chile or the west coast of Sumatra . The largest shelf—the Siberian Shelf in the Arctic Ocean —stretches to 1,500 kilometers (930 mi) in width. The South China Sea lies over another extensive area of continental shelf, the Sunda Shelf , which joins Borneo , Sumatra, and Java to the Asian mainland. Other familiar bodies of water that overlie continental shelves are the North Sea and

4650-567: The coast; sand is limited to shallow, wave-agitated waters, while silt and clays are deposited in quieter, deep water far offshore. These accumulate 15–40 centimetres (5.9–15.7 in) every millennium, much faster than deep-sea pelagic sediments . "Shelf seas" are the ocean waters on the continental shelf. Their motion is controlled by the combined influences of the tides , wind-forcing and brackish water formed from river inflows ( Regions of Freshwater Influence ). These regions can often be biologically highly productive due to mixing caused by

4743-464: The competing claims had an area of 175,000 square kilometres (68,000 sq mi), which is approximately 12% of the total area of the Barents Sea. The two countries started negotiations on the location of the boundary in 1974 and agreed to a moratorium on hydrocarbon exploration in 1976. Twenty years after the fall of the Soviet Union, in 2010 Norway and Russia signed an agreement that placed

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4836-420: The continental shelf constitutes the neritic zone , and the benthic (sea floor) province of the shelf is the sublittoral zone . The shelves make up less than 10% of the ocean, and a rough estimate suggests that only about 30% of the continental shelf sea floor receives enough sunlight to allow benthic photosynthesis. Though the shelves are usually fertile, if anoxic conditions prevail during sedimentation,

4929-428: The deep ocean floor, the abyssal plain . The continental shelf and the slope are part of the continental margin . The shelf area is commonly subdivided into the inner continental shelf , mid continental shelf , and outer continental shelf , each with their specific geomorphology and marine biology . The character of the shelf changes dramatically at the shelf break, where the continental slope begins. With

5022-418: The deep sea. The continental shelves are covered by terrigenous sediments ; that is, those derived from erosion of the continents. However, little of the sediment is from current rivers ; some 60–70% of the sediment on the world's shelves is relict sediment , deposited during the last ice age, when sea level was 100–120 m lower than it is now. Sediments usually become increasingly fine with distance from

5115-433: The deposits may over geologic time become sources for fossil fuels . The continental shelf is the best understood part of the ocean floor, as it is relatively accessible. Most commercial exploitation of the sea, such as extraction of metallic ore, non-metallic ore, and hydrocarbons , takes place on the continental shelf. Sovereign rights over their continental shelves down to a depth of 100 m (330 ft) or to

5208-451: The east (towards Novaya Zemlya ), it can be quite diffuse and its position can vary markedly between years. The lands of Novaya Zemlya attained most of their early Holocene coastal deglaciation approximately 10,000 years before the present. The International Hydrographic Organization defines the limits of the "Barentsz Sea" [ sic ] as follows: Other islands in the Barents Sea include Chaichy and Timanets. The Barents Sea

5301-622: The entire Barents Sea is more or less completely ice-free. From 1920 to 1944, Finland 's territory also reached the Barents Sea. The Liinakhamari harbour in the Pechengsky District was Finland's only ice-free winter harbour until 1944 when it was ceded to the Soviet Union . There are three main types of water masses in the Barents Sea: Warm, salty Atlantic water (temperature >3 °C, salinity >35) from

5394-534: The first recorded complete man-powered crossing of the Barents Sea from Tromsø to Longyearbyen in a rowboat by the Polar Row expedition, captain Fiann Paul was asked by Norwegian TV2 how a rower would name the Barents Sea. Fiann responded that he would name it "Devil's Jaw", adding that the winds you constantly battle are like breath from the devil's nostrils while he holds you in his jaws. Seabed mapping

5487-498: The first trophic level. Organisms such as zooplankton feed on these phytoplankton which are in turn fed on by other organisms and so forth until the fourth trophic level is reached with apex predators. Approximately 90% of total carbon is lost between trophic levels due to respiration, detritus, and dissolved organic matter. This makes the remineralization process and nutrient cycling performed by phytoplankton and bacteria important in maintaining efficiency. Phytoplankton blooms in which

5580-410: The flatter continental rise , in which sediment from the continent above cascades down the slope and accumulates as a pile of sediment at the base of the slope. Extending as far as 500 km (310 mi) from the slope, it consists of thick sediments deposited by turbidity currents from the shelf and slope. The continental rise 's gradient is intermediate between the gradients of the slope and

5673-513: The global population of phytoplankton is an area of active research. Changes in the vertical stratification of the water column, the rate of temperature-dependent biological reactions, and the atmospheric supply of nutrients are expected to have important effects on future phytoplankton productivity. The effects of anthropogenic ocean acidification on phytoplankton growth and community structure has also received considerable attention. The cells of coccolithophore phytoplankton are typically covered in

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5766-513: The global warming exceeds 1.5 degrees. This rapid warming also makes it easier to detect any potential connections between the state of sea ice and weather conditions elsewhere than in any other area. The first study proposing a connection between floating ice decline in the Barents Sea and the neighbouring Kara Sea and more intense winters in Europe was published in 2010, and there has been extensive research into this subject since then. For instance,

5859-413: The ice edge because the fresh water from the melting ice makes up a stable water layer on top of the seawater. The phytoplankton bloom feeds zooplankton such as Calanus finmarchicus , Calanus glacialis , Calanus hyperboreus , Oithona spp., and krill . The zooplankton feeders include young cod , capelin , polar cod , whales , and little auk . The capelin is a key food for top predators such as

5952-436: The key mediators of the biological pump . Understanding the response of phytoplankton to changing environmental conditions is a prerequisite to predict future atmospheric concentrations of CO 2 . Temperature, irradiance and nutrient concentrations, along with CO 2 are the chief environmental factors that influence the physiology and stoichiometry of phytoplankton. The stoichiometry or elemental composition of phytoplankton

6045-507: The location of the main sedimentary basins . NorskHydro drilled the first well in 1980, which was a dry hole, and the first discoveries were made the following year: the Alke and Askeladden gas fields. Several more discoveries were made on the Norwegian side of the Barents Sea throughout the 1980s, including the important Snøhvit field . However, interest in the area began to wane due to

6138-578: The major rift basins that dominate the Barents Shelf, along with various platforms and structural highs. The later geological history of the Barents Sea is dominated by Late Cenozoic uplift , particularly that caused by Quaternary glaciation , which has resulted in erosion and deposition of significant sediment. Due to the North Atlantic drift , the Barents Sea has a high biological production compared to other oceans of similar latitude. The spring bloom of phytoplankton can start quite early near

6231-501: The many food chains in the ocean – remarkable due to the small number of links – is that of phytoplankton sustaining krill (a crustacean similar to a tiny shrimp), which in turn sustain baleen whales . The El Niño-Southern Oscillation (ENSO) cycles in the Equatorial Pacific area can affect phytoplankton. Biochemical and physical changes during ENSO cycles modify the phytoplankton community structure. Also, changes in

6324-592: The more dominant phytoplankton and reflect a larger portion of the biomass . In the early twentieth century, Alfred C. Redfield found the similarity of the phytoplankton's elemental composition to the major dissolved nutrients in the deep ocean. Redfield proposed that the ratio of carbon to nitrogen to phosphorus (106:16:1) in the ocean was controlled by the phytoplankton's requirements, as phytoplankton subsequently release nitrogen and phosphorus as they are remineralized. This so-called " Redfield ratio " in describing stoichiometry of phytoplankton and seawater has become

6417-559: The north-east Arctic cod , harp seals , and seabirds such as the common guillemot and Brunnich's guillemot . The fisheries of the Barents Sea, in particular the cod fisheries, are of great importance for both Norway and Russia. SIZEX-89 was an international winter experiment in 1989 for which the main objectives were to perform sensor signature studies of different ice types to develop SAR algorithms for ice variables, such as ice types, ice concentrations and ice kinematics. Although previous research suggested that predation by whales may be

6510-402: The northern areas of Norway play a central role in this strategy. They have excellent access to unique Arctic marine organisms, existing marine industries, and R&D competence and infrastructure in this region. Since 2007, science and industry have cooperated closely on bioprospecting and the development and commercialization of new products. Continental shelf A continental shelf

6603-579: The northern end of the Ural Mountains , separate the Barents Sea from the Kara Sea . Although part of the Arctic Ocean, the Barents Sea has been characterised as "turning into the Atlantic " or in the process of being "Atlantified" because of its status as "the Arctic warming hot spot." Hydrologic changes due to global warming have led to a reduction in sea ice and in the stratification of

6696-498: The number of different species within a given area. This increase in plankton diversity is traced to warming ocean temperatures. In addition to species richness changes, the locations where phytoplankton are distributed are expected to shift towards the Earth's poles. Such movement may disrupt ecosystems, because phytoplankton are consumed by zooplankton, which in turn sustain fisheries. This shift in phytoplankton location may also diminish

6789-504: The ocean. Controversy about manipulating the ecosystem and the efficiency of iron fertilization has slowed such experiments. The ocean science community still has a divided attitude toward the study of iron fertilization as a potential marine Carbon Dioxide Removal (mCDR) approach. Phytoplankton depend on B vitamins for survival. Areas in the ocean have been identified as having a major lack of some B Vitamins, and correspondingly, phytoplankton. The effects of anthropogenic warming on

6882-520: The oceans such as the Southern Ocean , phytoplankton are often limited by the lack of the micronutrient iron . This has led to some scientists advocating iron fertilization as a means to counteract the accumulation of human-produced carbon dioxide (CO 2 ) in the atmosphere . Large-scale experiments have added iron (usually as salts such as ferrous sulfate ) to the oceans to promote phytoplankton growth and draw atmospheric CO 2 into

6975-422: The oxygen production despite amounting to only ~1% of global plant biomass. In comparison with terrestrial plants, marine phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). Therefore, phytoplankton respond rapidly on a global scale to climate variations. These characteristics are important when one

7068-434: The past century, but these conclusions have been questioned because of the limited availability of long-term phytoplankton data, methodological differences in data generation and the large annual and decadal variability in phytoplankton production. Moreover, other studies suggest a global increase in oceanic phytoplankton production and changes in specific regions or specific phytoplankton groups. The global Sea Ice Index

7161-487: The poles. Phytoplankton release dissolved organic carbon (DOC) into the ocean. Since phytoplankton are the basis of marine food webs , they serve as prey for zooplankton , fish larvae and other heterotrophic organisms. They can also be degraded by bacteria or by viral lysis . Although some phytoplankton cells, such as dinoflagellates , are able to migrate vertically, they are still incapable of actively moving against currents, so they slowly sink and ultimately fertilize

7254-853: The population of cloud condensation nuclei , mostly leading to increased cloud cover and cloud albedo according to the so-called CLAW hypothesis . Different types of phytoplankton support different trophic levels within varying ecosystems. In oligotrophic oceanic regions such as the Sargasso Sea or the South Pacific Gyre , phytoplankton is dominated by the small sized cells, called picoplankton and nanoplankton (also referred to as picoflagellates and nanoflagellates), mostly composed of cyanobacteria ( Prochlorococcus , Synechococcus ) and picoeucaryotes such as Micromonas . Within more productive ecosystems, dominated by upwelling or high terrestrial inputs, larger dinoflagellates are

7347-570: The role of phytoplankton aerosol emissions on Earth's energy budget. NAAMES was designed to target specific phases of the annual phytoplankton cycle: minimum, climax and the intermediary decreasing and increasing biomass, in order to resolve debates on the timing of bloom formations and the patterns driving annual bloom re-creation. The NAAMES project also investigated the quantity, size, and composition of aerosols generated by primary production in order to understand how phytoplankton bloom cycles affect cloud formations and climate. Phytoplankton are

7440-488: The seafloor with dead cells and detritus . Phytoplankton are crucially dependent on a number of nutrients . These are primarily macronutrients such as nitrate , phosphate or silicic acid , which are required in relatively large quantities for growth. Their availability in the surface ocean is governed by the balance between the so-called biological pump and upwelling of deep, nutrient-rich waters. The stoichiometric nutrient composition of phytoplankton drives — and

7533-437: The search for bioactive molecules and compounds from marine sources that have new, unique properties and the potential for commercial applications. Amongst others, applications include medicines, food and feed, textiles, cosmetics and the process industry. The Norwegian government strategically supports the development of marine bioprospecting as it has the potential to contribute to new and sustainable wealth creation. Tromsø and

7626-400: The shallower waters and the enhanced current speeds. Despite covering only about 8% of Earth's ocean surface area, shelf seas support 15–20% of global primary productivity . In temperate continental shelf seas, three distinctive oceanographic regimes are found, as a consequence of the interplay between surface heating, lateral buoyancy gradients (due to river inflow), and turbulent mixing by

7719-519: The shelf. Under the United Nations Convention on the Law of the Sea , the name continental shelf was given a legal definition as the stretch of the seabed adjacent to the shores of a particular country to which it belongs. The shelf usually ends at a point of increasing slope (called the shelf break ). The sea floor below the break is the continental slope . Below the slope is the continental rise , which finally merges into

7812-432: The structure of the phytoplankton, such as a significant reduction in biomass and phytoplankton density, particularly during El Nino phases can occur. The sensitivity of phytoplankton to environmental changes is why they are often used as indicators of estuarine and coastal ecological condition and health. To study these events satellite ocean color observations are used to observe these changes. Satellite images help to have

7905-406: The sun, so they live in the well-lit surface layers ( euphotic zone ) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form

7998-459: The tides and to a lesser extent the wind. Indian Ocean shelf seas are dominated by major river systems, including the Ganges and Indus rivers. The shelf seas around New Zealand are complicated because the submerged continent of Zealandia creates wide plateaus. Shelf seas around Antarctica and the shores of the Arctic Ocean are influenced by sea ice production and polynya . There

8091-501: The upper sunlit layer of marine and fresh water bodies of water on Earth. Paralleling plants on land, phytoplankton undertake primary production in water, creating organic compounds from carbon dioxide dissolved in the water. Phytoplankton form the base of — and sustain — the aquatic food web , and are crucial players in the Earth's carbon cycle . Phytoplankton are very diverse, comprising photosynthesizing bacteria ( cyanobacteria ) and various unicellular protist groups (notably

8184-446: The various environmental factors that together affect phytoplankton productivity . All of these factors are expected to undergo significant changes in the future ocean due to global change. Global warming simulations predict oceanic temperature increase; dramatic changes in oceanic stratification , circulation and changes in cloud cover and sea ice, resulting in an increased light supply to the ocean surface. Also, reduced nutrient supply

8277-489: The water column, which could produce major changes in weather in Eurasia . One prediction is that, as the Barents Sea's permanent ice-free area grows, evaporation will increase, leading to increased winter snowfalls in much of continental Europe. The southern half of the Barents Sea, including the ports of Murmansk (Russia) and Vardø (Norway) remain ice -free year-round due to the warm North Atlantic drift . In September,

8370-471: The wavelength of light different efficiently and the light is not a single ecological resource but a multitude of resources depending on its spectral composition. By that it was found that changes in the spectrum of light alone can alter natural phytoplankton communities even if the same intensity is available. For growth, phytoplankton cells additionally depend on nutrients, which enter the ocean by rivers, continental weathering, and glacial ice meltwater on

8463-402: The world ocean using ocean-colour data from satellites, and found the calorific value of phytoplankton to vary considerably across different oceanic regions and between different time of the year. The production of phytoplankton under artificial conditions is itself a form of aquaculture. Phytoplankton is cultured for a variety of purposes, including foodstock for other aquacultured organisms,

8556-452: Was completed in 1933; the first full map was produced by Russian marine geologist Maria Klenova . The Barents Sea was the site of a notable World War II engagement which later became known as the Battle of the Barents Sea . Under the command of Oskar Kummetz , German warships sank minelayer HMS Bramble and destroyer HMS  Achates but lost destroyer Z16 Friedrich Eckoldt . Also,

8649-582: Was originally formed from two major continental collisions: the Caledonian orogeny , in which the Baltica and Laurentia collided to form Laurasia , and a subsequent collision between Laurasia and Western Siberia. Most of its geological history is dominated by extensional tectonics , caused by the collapse of the Caledonian and Uralian orogenic belts and the break-up of Pangaea . These events created

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