1.
Ocean current
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Depth contours, shoreline configurations, and interactions with other currents influence a currents direction and strength. Therefore ocean currents are primarily horizontal water movements, Ocean currents flow for great distances, and together, create the global conveyor belt which plays a dominant role in determining the climate of many of the Earth’s regions. More specifically, ocean currents influence the temperature of the regions through which they travel, for example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them. Perhaps the most striking example is the Gulf Stream, which makes northwest Europe much more temperate than any region at the same latitude. Another example is Lima, Peru where the climate is cooler than the tropical latitudes in which the area is located, in these wind driven currents, the Ekman spiral effect results in the currents flowing at an angle to the driving winds. In addition, the areas of ocean currents move somewhat with the seasons. Deep ocean basins generally have a surface current, in that the eastern equatorward-flowing branch is broad. These western boundary currents are a consequence of the rotation of the Earth, Deep ocean currents are driven by density and temperature gradients. Thermohaline circulation is known as the oceans conveyor belt. These currents, called submarine rivers, flow under the surface of the ocean and are hidden from immediate detection, where significant vertical movement of ocean currents is observed, this is known as upwelling and downwelling. Deep ocean currents are currently being researched using a fleet of robots called Argo. The South Equatorial Currents of the Atlantic and Pacific straddle the equator, though the Coriolis effect is weak near the equator, water moving in the currents on either side of the equator is deflected slightly poleward and replaced by deeper water. Thus, equatorial upwelling occurs in these westward flowing equatorial surface currents, upwelling is an important process because this water from within and below the pycnocline is often rich in nutrients and greatly benefits the growth of marine organisms. By contrast, generally poor conditions for growth prevail in most of the tropical ocean because strong layering isolates deep. Ocean currents are measured in sverdrup, where 1 sv is equivalent to a flow rate of 1,000,000 m3 per second. Surface currents are found on the surface of an ocean, and are driven by large scale wind currents and they are directly affected by the wind—the Coriolis effect plays a role in their behaviors. Horizontal and vertical currents also exist below the pycnocline in the deeper waters. The movement of water due to differences in density as a function of water temperature, ripple marks in sediments, scour lines, and the erosion of rocky outcrops on deep-ocean floors are evidence that relatively strong, localized bottom currents exist
2.
Atlantic Ocean
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The Atlantic Ocean is the second largest of the worlds oceans with a total area of about 106,460,000 square kilometres. It covers approximately 20 percent of the Earths surface and about 29 percent of its surface area. It separates the Old World from the New World, the Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Eurasia and Africa to the east, and the Americas to the west. The Equatorial Counter Current subdivides it into the North Atlantic Ocean, in contrast, the term Atlantic originally referred specifically to the Atlas Mountains in Morocco and the sea off the Strait of Gibraltar and the North African coast. The Greek word thalassa has been reused by scientists for the huge Panthalassa ocean that surrounded the supercontinent Pangaea hundreds of years ago. The term Aethiopian Ocean, derived from Ancient Ethiopia, was applied to the Southern Atlantic as late as the mid-19th century, many Irish or British people refer to the United States and Canada as across the pond, and vice versa. The Black Atlantic refers to the role of ocean in shaping black peoples history. Irish migration to the US is meant when the term The Green Atlantic is used, the term Red Atlantic has been used in reference to the Marxian concept of an Atlantic working class, as well as to the Atlantic experience of indigenous Americans. Correspondingly, the extent and number of oceans and seas varies, the Atlantic Ocean is bounded on the west by North and South America. It connects to the Arctic Ocean through the Denmark Strait, Greenland Sea, Norwegian Sea, to the east, the boundaries of the ocean proper are Europe, the Strait of Gibraltar and Africa. In the southeast, the Atlantic merges into the Indian Ocean, the 20° East meridian, running south from Cape Agulhas to Antarctica defines its border. In the 1953 definition it extends south to Antarctica, while in later maps it is bounded at the 60° parallel by the Southern Ocean, the Atlantic has irregular coasts indented by numerous bays, gulfs, and seas. Including these marginal seas the coast line of the Atlantic measures 111,866 km compared to 135,663 km for the Pacific. Including its marginal seas, the Atlantic covers an area of 106,460,000 km2 or 23. 5% of the ocean and has a volume of 310,410,900 km3 or 23. 3%. Excluding its marginal seas, the Atlantic covers 81,760,000 km2 and has a volume of 305,811,900 km3, the North Atlantic covers 41,490,000 km2 and the South Atlantic 40,270,000 km2. The average depth is 3,646 m and the maximum depth, the bathymetry of the Atlantic is dominated by a submarine mountain range called the Mid-Atlantic Ridge. It runs from 87°N or 300 km south of the North Pole to the subantarctic Bouvet Island at 42°S, the MAR divides the Atlantic longitudinally into two halves, in each of which a series of basins are delimited by secondary, transverse ridges. The MAR reaches above 2000 m along most of its length, the MAR is a barrier for bottom water, but at these two transform faults deep water currents can pass from one side to the other
3.
Cape Point
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Table Mountain and the city of Cape Town are close to the northern extremity of the same peninsula. The cape is located at 34°21′26″S 18°29′51″E, about 2.3 kilometres east, the peak above Cape Point is higher than that above the Cape of Good Hope. The rugged sandstone ridge that rises from Cape Point at sea level develops into two peaks, there is a major peak that dominates the skyline locally but there is also a smaller peak about 100 m further south. The higher peak has the old lighthouse on the top, from the end of the railway a second path leads to the lower peak. Secondly, foggy conditions often prevail at the levels, making the older lighthouse invisible to shipping. On 18 April 1911, the Portuguese liner Lusitania was wrecked just south of Cape Point at 34°23′22″S 18°29′23″E on Bellows Rock for precisely this reason, prompting the relocation of the lighthouse. The new lighthouse, located at 34°21′26″S 18°29′49″E, cannot be seen from the West until ships are at a distance to the South. The light of the new Cape Point lighthouse is the most powerful on the South African coast, with a range of 63 miles, Cape Point is situated within the Table Mountain National Park, within a section of the park referred to as Cape of Good Hope. This section covers the whole of the tip of the Cape Peninsula. The Cape of Good Hope section of the park is generally wild, the vegetation at Cape Point consists primarily of Peninsula Sandstone Fynbos. Cape Point is often claimed to be the place where the cold Benguela Current of the Atlantic Ocean. In fact, the meeting point fluctuates along the southern and southwestern Cape coast, the two intermingling currents help to create the micro-climate of Cape Town and its environs. Contrary to popular mythology, the point of the currents produces no obvious visual effect. There are, however, strong and dangerous swells, tides and localized currents around the point and these troubled seas have witnessed countless maritime disasters in the centuries since ships first sailed here. Fishing is good along the coast but the unpredictable swells make angling from the very dangerous. Over the years scores of fishermen have been swept to their deaths from the platforms by freak waves. False Bay, which opens to the east and north of Cape Point, is the location of the naval port of Simons Town. The bay is also famous - or infamous - for its great white sharks, Cape Point is the site of one of the Global Atmosphere Watchs atmospheric research stations
4.
Angola
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Angola /æŋˈɡoʊlə/, officially the Republic of Angola, is a country in Southern Africa. It is the seventh-largest country in Africa and is bordered by Namibia to the south, the Democratic Republic of the Congo to the north, Zambia to the east, and the Atlantic Ocean to west. The exclave province of Cabinda has borders with the Republic of the Congo, the capital and largest city of Angola is Luanda. In the 19th century, European settlers slowly and hesitantly began to themselves in the interior. As a Portuguese colony, Angola did not encompass its present borders until the early 20th century, following resistance by groups such as the Cuamato, the Kwanyama and the Mbunda. Independence was achieved in 1975 under a communist one-party state backed by the Soviet Union, however, the country soon descended into an even lengthier civil war that lasted until 2002. It has since become a relatively stable presidential republic. Angola has vast mineral and petroleum reserves, and its economy is among the fastest growing in the world, Angolas economic growth is highly uneven, with the majority of the nations wealth concentrated in a disproportionately small sector of the population. Angola is a state of the United Nations, OPEC, African Union, the Community of Portuguese Language Countries, the Latin Union. A highly multiethnic country, Angolas 25.8 million people span various tribal groups, customs, Angolan culture reflects centuries of Portuguese rule, namely in the predominance of the Portuguese language and the Catholic Church, combined with diverse indigenous influences. The name Angola comes from the Portuguese colonial name Reino de Angola, the toponym was derived by the Portuguese from the title ngola held by the kings of Ndongo. Ndongo was a kingdom in the highlands, between the Kwanza and Lukala Rivers, nominally tributary to the king of Kongo but which was seeking greater independence during the 16th century, modern Angola was populated predominantly by nomadic Khoi and San prior to the first Bantu migrations. The Khoi and San peoples were neither pastoralists nor cultivators, following a hunter-gatherer lifestyle and they were displaced by Bantu peoples arriving from the north, some of whom likely originated in northwestern Nigeria. Bantu speakers introduced the cultivation of bananas and taro, as well as large herds, to Angolas central highlands. During this time, the Bantu established a number of entities in most of what today comprises Angola. To its south lay the Kingdom of Ndongo, from which the area of the later Portuguese colony was known as Dongo. The region now known as Angola was reached by the Portuguese explorer Diogo Cão in 1484, the year before, the Portuguese had established relations with the Kongo, which stretched at the time from modern Gabon in the north to the Kwanza River in the south. The Portuguese established their primary trading post at Soyo, which is now the northernmost city in Angola apart from the Cabinda exclave
5.
Phytoplankton
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Phytoplankton /ˌfaɪtoʊˈplæŋktən/ are the autotrophic components of the plankton community and a key part of oceans, seas and freshwater basin ecosystems. The name comes from the Greek words φυτόν, meaning plant, most phytoplankton are too small to be individually seen with the unaided eye. Phytoplankton are photosynthesizing microscopic organisms that inhabit the upper layer of almost all oceans. They are agents for primary production, the creation of organic compounds from carbon dioxide dissolved in the water, Phytoplankton obtain energy through the process of photosynthesis and must therefore live in the well-lit surface layer of an ocean, sea, lake, or other body of water. Phytoplankton account for half of all activity on Earth. Their cumulative energy fixation in carbon compounds is the basis for the vast majority of oceanic, the effects of anthropogenic warming on the global population of phytoplankton is an area of active research. Additionally, changes in the mortality of phytoplankton due to rates of zooplankton grazing may be significant, as a side note, one of the more remarkable food chains in the ocean – remarkable because of the small number of links – is that of phytoplankton-feeding krill feeding baleen whales. Phytoplankton are also dependent on minerals. However, across large regions of the World Ocean such as the Southern Ocean and this has led to some scientists advocating iron fertilization as a means to counteract the accumulation of human-produced carbon dioxide in the atmosphere. Large-scale experiments have added iron to the oceans to promote phytoplankton growth, however, controversy about manipulating the ecosystem and the efficiency of iron fertilization has slowed such experiments. Phytoplankton depend on other substances to survive as well, in particular, Vitamin B is crucial. Areas in the ocean have been identified as having a lack of Vitamin B. While almost all species are obligate photoautotrophs, there are some that are mixotrophic and other. Of these, the best known are dinoflagellate genera such as Noctiluca and Dinophysis, the term phytoplankton encompasses all photoautotrophic microorganisms in aquatic food webs. Phytoplankton serve as the base of the food web, providing an essential ecological function for all aquatic life. However, unlike terrestrial communities, where most autotrophs are plants, phytoplankton are a group, incorporating protistan eukaryotes. There are about 5,000 known species of marine phytoplankton, how such diversity evolved despite scarce resources is unclear. In terms of numbers, the most important groups of phytoplankton include the diatoms, cyanobacteria and dinoflagellates, one group, the coccolithophorids, is responsible for the release of significant amounts of dimethyl sulfide into the atmosphere
6.
Zooplankton
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Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word zooplankton is derived from the Greek zoon, meaning animal, individual zooplankton are usually microscopic, but some are larger and visible with the naked eye. Zooplankton is a categorization spanning a range of organism sizes including small protozoans, although zooplankton are primarily transported by ambient water currents, many have locomotion, used to avoid predators or to increase prey encounter rate. Ecologically important protozoan zooplankton groups include the foraminiferans, radiolarians and dinoflagellates and this wide phylogenetic range includes a similarly wide range in feeding behavior, filter feeding, predation and symbiosis with autotrophic phytoplankton as seen in corals. Zooplankton feed on bacterioplankton, phytoplankton, other zooplankton, detritus, as a result, zooplankton are primarily found in surface waters where food resources are abundant. Just as any species can be limited within a geographical region, however, species of zooplankton are not dispersed uniformly or randomly within a region of the ocean. As with phytoplankton, ‘patches’ of zooplankton species exist throughout the ocean, zooplankton patchiness can also be influenced by biological factors, as well as other physical factors. Biological factors include breeding, predation, concentration of phytoplankton, the physical factor that influences zooplankton distribution the most is mixing of the water column that affects nutrient availability and, in turn, phytoplankton production. Since they are small, zooplankton can respond rapidly to increases in phytoplankton abundance, for instance. Zooplankton can also act as a disease reservoir, crustacean zooplankton have been found to house the bacterium Vibrio cholerae, which causes cholera, by allowing the cholera vibrios to attach to their chitinous exoskeletons. This symbiotic relationship enhances the ability to survive in an aquatic environment, as the exoskeleton provides the bacterium with carbon. A global coverage database of zooplankton biomass and abundance data
7.
Namibia
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Namibia, officially the Republic of Namibia, is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south, although it does not border Zimbabwe, a part of less than 200 metres of the Zambezi River separates the two countries. Namibia gained independence from South Africa on 21 March 1990, following the Namibian War of Independence. Its capital and largest city is Windhoek, and it is a state of the United Nations, the Southern African Development Community, the African Union. The dry lands of Namibia were inhabited since early times by the San, Damara, since about the 14th century, immigrating Bantu peoples arrived as part of the Bantu expansion. Since then the Bantu groups in total, known as the Ovambo people, have dominated the population of the country, in the late 19th century during European colonization, the German Empire established rule over most of the territory as a protectorate in 1884. It began to develop infrastructure and farming, and maintained this German colony until 1915, after the end of World War I, in 1920 the League of Nations mandated the country to the United Kingdom, under administration by South Africa. It imposed its laws, including racial classifications and rules, from 1948, with the National Party elected to power, South Africa applied apartheid also to what was known as South West Africa. In 1878 the Cape of Good Hope had annexed the port of Walvis Bay and the offshore Penguin Islands, following continued guerrilla warfare, South Africa installed an interim administration in Namibia in 1985. Namibia obtained full independence from South Africa in 1990, but Walvis Bay and the Penguin Islands remained under South African control until 1994. Namibia has a population of 2.1 million people and a stable multi-party parliamentary democracy, Agriculture, herding, tourism and the mining industry – including mining for gem diamonds, uranium, gold, silver, and base metals – form the basis of its economy. The large, arid Namib Desert has resulted in Namibia being overall one of the least densely populated countries in the world, Namibia enjoys high political, economic and social stability. The name of the country is derived from the Namib Desert, before its independence in 1990, the area was known first as German South-West Africa, then as South-West Africa, reflecting the colonial occupation by the Germans and the South Africans. The dry lands of Namibia were inhabited since early times by San, Damara, from about the 14th century, immigrating Bantu peoples arrived during the Bantu expansion from central Africa. From the late 18th century onwards, Oorlam people from Cape Colony crossed the Orange River and their encounters with the nomadic Nama tribes were largely peaceful. The missionaries accompanying the Oorlam were well received by them, the right to use waterholes, on their way further northwards, however, the Oorlam encountered clans of the Herero at Windhoek, Gobabis, and Okahandja, who resisted their encroachment. The Nama-Herero War broke out in 1880, with hostilities ebbing only after the German Empire deployed troops to the places and cemented the status quo among the Nama, Oorlam. The first Europeans to disembark and explore the region were the Portuguese navigators Diogo Cão in 1485 and Bartolomeu Dias in 1486, like most of interior Sub-Saharan Africa, Namibia was not extensively explored by Europeans until the 19th century
8.
Indian Ocean
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The Indian Ocean is the third largest of the worlds oceanic divisions, covering 70,560,000 km2. It is bounded by Asia on the north, on the west by Africa, on the east by Australia, the Indian Ocean is known as Ratnākara, the mine of gems in ancient Sanskrit literature, and as Hind Mahāsāgar, in Hindi. The northernmost extent of the Indian Ocean is approximately 30° north in the Persian Gulf, the oceans continental shelves are narrow, averaging 200 kilometres in width. An exception is found off Australias western coast, where the width exceeds 1,000 kilometres. The average depth of the ocean is 3,890 m and its deepest point is Diamantina Deep in Diamantina Trench, at 8,047 m deep, Sunda Trench has a depth of 7, 258–7,725 m. North of 50° south latitude, 86% of the basin is covered by pelagic sediments. The remaining 14% is layered with terrigenous sediments, glacial outwash dominates the extreme southern latitudes. The major choke points include Bab el Mandeb, Strait of Hormuz, the Lombok Strait, the Strait of Malacca, the Indian Ocean is artificially connected to the Mediterranean Sea through the Suez Canal, which is accessible via the Red Sea. All of the Indian Ocean is in the Eastern Hemisphere and the centre of the Eastern Hemisphere is in this ocean, marginal seas, gulfs, bays and straits of the Indian Ocean include, The climate north of the equator is affected by a monsoon climate. Strong north-east winds blow from October until April, from May until October south, in the Arabian Sea the violent Monsoon brings rain to the Indian subcontinent. In the southern hemisphere, the winds are milder. When the monsoon winds change, cyclones sometimes strike the shores of the Arabian Sea, the Indian Ocean is the warmest ocean in the world. Long-term ocean temperature records show a rapid, continuous warming in the Indian Ocean, Indian Ocean warming is the largest among the tropical oceans, and about 3 times faster than the warming observed in the Pacific. Research indicates that human induced greenhouse warming, and changes in the frequency, among the few large rivers flowing into the Indian Ocean are the Zambezi, Shatt al-Arab, Indus, Godavari, Krishna, Narmada, Ganges, Brahmaputra, Jubba and Irrawaddy River. The oceans currents are controlled by the monsoon. Two large gyres, one in the northern hemisphere flowing clockwise and one south of the equator moving anticlockwise, during the winter monsoon, however, currents in the north are reversed. Deep water circulation is controlled primarily by inflows from the Atlantic Ocean, the Red Sea, north of 20° south latitude the minimum surface temperature is 22 °C, exceeding 28 °C to the east. Southward of 40° south latitude, temperatures drop quickly, surface water salinity ranges from 32 to 37 parts per 1000, the highest occurring in the Arabian Sea and in a belt between southern Africa and south-western Australia
9.
Cape Agulhas
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Cape Agulhas is a rocky headland in Western Cape, South Africa. It is the southern tip of the African continent and the beginning of the dividing line between the Atlantic and Indian Oceans according to the International Hydrographic Organization. Historically, the cape has been known to sailors as a hazard on the traditional clipper route. It is sometimes regarded as one of the great capes and it was most commonly known in English as Cape LAgulhas until the 20th century. The town of LAgulhas is located near to the cape, Cape Agulhas is located in the Overberg region,170 kilometres southeast of Cape Town. The cape is within the Cape Agulhas Local Municipality in the Overberg District of the Western Cape province of South Africa, the nearby small airport of Andrews Field services Agulhas. South of Cape Agulhas the warm Agulhas Current that flows south along the east coast of Africa retroflects back into the Indian Ocean. While retroflecting, it pinches off large ocean eddies that drift into the South Atlantic Ocean and take enormous amounts of heat and this mechanism constitutes one of the key elements in the global conveyor belt circulation of heat and salt. Unlike its better-known relative, the Cape of Good Hope, Cape Agulhas is relatively unspectacular, a survey marker indicates the location of the cape, which would otherwise be difficult to identify. The waters of the Agulhas Bank off the coast are quite shallow and are renowned as one of the best fishing grounds in South Africa, the rocks that form Cape Agulhas belong to the Table Mountain Group, often loosely termed the Table Mountain sandstone. They are closely linked to the formations that are exposed in the spectacular cliffs of Table Mountain, Cape Point. The climate is mild, with no temperature or rainfall extremes. According to South African National Parks, who administer the nature reserve, over the past few hundred years it has been believed that around 150 ships have sunk around Agulhas. These conditions are caused by a number of factors and these hazards have combined to make the cape notorious among sailors. The coast here is littered with wrecks, Arniston, Cooranga, Elise, Federal Lakes, Geortyrder, Gouritz, owing to the hazards and following the loss of several vessels, notably the Arniston, a lighthouse was built in 1848. The lighthouse now plays host to a museum and a rustic restaurant. Cape Agulhas Local Municipality, the municipality containing Cape Agulhas, Agulhas National Park Cape of Good Hope, near Cape Town, often incorrectly regarded as the southernmost point of Africa. SS Wafra oil spill Cape Agulhas Lighthouse Agulhas National Park
10.
Anchovy
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An anchovy is a small, common salt-water forage fish of the family Engraulidae. The 144 species are placed in 17 genera, they are found in the Atlantic, Indian, and Pacific Oceans, and in the Black Sea, Anchovies are usually classified as oily fish. Anchovies are small, green fish with blue reflections due to a longitudinal stripe that runs from the base of the caudal fin. They range from 2 to 40 cm in length. The snout is blunt with tiny, sharp teeth in both jaws, the snout contains a unique rostral organ, believed to be sensory in nature, although its exact function is unknown. The mouth is larger than that of herrings and silversides, two fish which anchovies closely resemble in other respects, the anchovy eats plankton and recently hatched fish. Anchovies are found in scattered areas throughout the oceans, but are concentrated in temperate waters. They are generally accepting of a wide range of temperatures. Large schools can be found in shallow, brackish areas with muddy bottoms, as in estuaries and they are abundant in the Mediterranean, particularly in the Alboran Sea, Aegean Sea and the Black Sea. The species is caught along the coasts of Crete, Greece, Sicily, Italy, France, Turkey. They are also found on the coast of northern Africa, the range of the species also extends along the Atlantic coast of Europe to the south of Norway. Spawning occurs between October and March, but not in water colder than 12 °C, the anchovy appears to spawn at least 100 km from the shore, near the surface of the water. The anchovy is a significant food source for almost every predatory fish in its environment, including the California halibut, rock fish, yellowtail, shark, chinook, and coho salmon. It is also important to marine mammals and birds, for example, breeding success of California brown pelicans. Anchovies, like most clupeoids, are filter-feeders that open their mouths as they swim, as water passes through the mouth and out the gills, food particles are sieved by gill rakers and transferred into the esophagus. * Type species On average, the Turkish commercial fishing fleet catches around 300,000 tons per year, the largest catch is in November and December. The Peruvian anchovy fishery is one of the largest in the world, in 1973 it collapsed catastrophically due to the combined effects of overfishing and El Niño and did not recover fully for two decades. A traditional method of processing and preserving anchovies is to gut and salt them in brine, allow them to mature and this results in a characteristic strong flavor and the flesh turns deep grey
11.
Benguela
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Benguela is a city in western Angola, south of Luanda, and capital of Benguela Province. It lies on a bay of the name, in 12° 33’ S. 13° 25’ E. Benguela is one of Angolas most populous cities. Benguela, a Portuguese fort from 1587, was founded in 1617 by the Portuguese under Manuel Cerveira Pereira and it was long the centre of an important trade, especially in slaves to Brazil and Cuba. Ships anchored about 1.6 kilometres off the shore, in depths of 7 to 11 metres, however the nearby deep-water sheltered harbour of Lobito was a much larger port. Besides the churches of S. Felipe and S. António, the hospital, a short way beyond Benguela is Baía Farta, where salt was manufactured and sulphur was extracted. Close to Baia Farta was the beach of Baia Azul, the city prospered and grew in the following decades. Starting in the early 20th century, Benguela attracted, developed, sisal and fishing industries expanded and the financial, construction and services market boomed until 1974. In 1975, after the April 1974 Carnation Revolution in Lisbon, Portugal, in the mid-2000s, with a more peaceful environment, restoration of the railway between Benguela and Huambo commenced. In 1983 Benguela had a population of 155,000, during the civil war the city of Benguela increased its population due to refugees from the countryside. While the colonial part of the city consists of relatively good-quality houses, Benguela was one of the centres of Portuguese trade to the African interior. The city remains an important commercial link between western and eastern Angola, coffee, corn, sisal, sugarcane, and tobacco are grown in the interior regions of Angola and widely traded in Benguela. Manganese from the interior is also traded in Benguela, industries local to the city include fish processing and the milling of sugarcane, the city also produces pottery, soap, and tools. Foreign trade is handled through the port of Lobito, which is located 29 kilometres north of Benguela. Lobito, once the busiest port in Angola, was disrupted during the Angolan Civil War. The port has since revived and supports trade in the Benguela region, the city formerly had a German school, Deutsche Schule Benguela. Leila Lopes - actress and Miss Universe 2011 Benguela Airport Benguela Railway Port of Lobito
12.
Upwelling
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The nutrient-rich upwelled water stimulates the growth and reproduction of primary producers such as phytoplankton. Due to the biomass of phytoplankton and presence of water in these regions, upwelling zones can be identified by cool sea surface temperatures. The increased availability in upwelling regions results in levels of primary productivity. Approximately 25% of the global marine fish catches come from five upwellings that occupy only 5% of the total ocean area. Upwellings that are driven by coastal currents or diverging open ocean have the greatest impact on nutrient-enriched waters, the three main drivers that work together to cause upwelling are wind, Coriolis effects, and Ekman transport. They operate differently for different types of upwelling, but the effects are the same. In the overall process of upwelling, winds blow across the sea surface at a particular direction, as a result of the wind, the water is transported a net of 90 degrees from the direction of the wind due to Coriolis forces and Ekman transport. This results in a spiral of water movement down the water column, then, it is the Coriolis forces that dictate which way the water will move, in the Northern hemisphere, the water is transported to the right of the direction of the wind. In the Southern Hemisphere, the water is transported to the left of the wind, if this net movement of water is divergent, then upwelling of deep water occurs to replace the water that was lost. The major upwellings in the ocean are associated with the divergence of currents that bring deeper, colder, coastal upwelling is the best known type of upwelling, and the most closely related to human activities as it supports some of the most productive fisheries in the world. Wind-driven currents are diverted to the right of the winds in the Northern Hemisphere, the result is a net movement of surface water at right angles to the direction of the wind, known as the Ekman transport. When Ekman transport is occurring away from the coast, surface waters moving away are replaced by deeper, colder, and denser water. Normally, this process occurs at a rate of about 5–10 meters per day. Deep waters are rich in nutrients, including nitrate, phosphate and silicic acid, Upwelling regions therefore result in very high levels of primary production in comparison to other areas of the ocean. They account for about 50% of global marine productivity, high primary production propagates up the food chain because phytoplankton are at the base of the oceanic food chain. All of these currents support major fisheries, the four major eastern boundary currents in which coastal upwelling primarily occurs are the Canary Current, Benguela Current, California Current, and Humboldt Current. The Benguela Current is the boundary of the South Atlantic subtropical gyre. The subsystems are divided by an area of permanent upwelling off of Luderitz, the California Current System is an eastern boundary current of the North Pacific that is also characterized by a north and south split
