Which two plates are squeezing the Atlantic ridge?

Farms on the northern shore of San Jorge Island in Azov Islands on the continental margin.

Including continental shelf, continental slope and continental uplift, its area accounts for about 1/3 of the ocean floor area. Among them, the continental shelf area is 92 1 10,000 square kilometers, accounting for11of the ocean floor area, slightly smaller than the Pacific Ocean and nearly twice that of the Indian Ocean. The width of the continental shelf ranges from tens of kilometers to Qian Qian meters. The Baltic Sea and the North Sea in the northeast of the Atlantic Ocean are the widest, and around the island of Great Britain in the northwest of Europe and along the coast of the Norwegian Sea, the widest point reaches 1000 km. It is one of the widest and largest continental shelves in the world. The widest part of the continental shelf along the coast of South America is also close to 1000 km, and the continental shelf near Newfoundland and Florida in North America is also relatively wide. However, the continental shelf of the African coast south of the Bay of Biscay is very narrow, not exceeding 100 km, and only 20-30 km in some areas. The continental shelf on the east coast of North America and the Caribbean coast on the north coast of South America are relatively narrow. The outer edge of the continental shelf is a continental slope, covering an area of about 7.68 million square kilometers. The continental slope along the continental shelf in Europe and Africa is steep, with a slope of about 5 ~ 10 and a width of only 20 ~ 30 kilometers. The continental slope of the United States is gentle, the slope is less than 3, and the width is more than 50 ~ 80 kilometers. On the other hand, there is a stepped continental slope on the western margin of the Mexican basin and the eastern side of Argentina, which gradually decreases from100 ~ 200m to a depth of more than 5000m, which is related to the intermittent uplift of the continental crust. The average slope of the Atlantic continental slope is 3 5', which is smaller than that of the Pacific Ocean. Between the continental slope and the ocean basin, there are some continental uplifts with much smaller slopes than the continental slope, such as Greenland-Iceland uplift, Blake uplift and Malvinas uplift. There are hundreds of submarine canyons on the continental slope, most of which are on the continental slope on the east side of North America, which are formed by turbidity current erosion, erosion or tectonic action.

Transition zone

Including island arcs, marginal basins, submarine highlands and deep trenches, the area is very small. There are two island arc belts and deep-sea trenches in the Atlantic Ocean: one is a double-island island arc belt (length 1550 km, average width 120 km, deepest 9218m); The other is the island arc extending eastward between the southern tip of South America and the Antarctic Peninsula, which consists of South Georgia, South Sandwich Islands and South Orkney Islands, and the South Sandwich Trench (about1450km long, with an average width of 70km and a maximum depth of 8264m) at the eastern edge of the island arc.

Mid-ocean ridge

Mid-ocean ridge, also known as ocean ridge, is the most special wonder of Atlantic seabed topography. It starts from Iceland in the north, runs through the Atlantic Ocean, reaches Bouvet Island in the south, and then turns northeast to connect with the mid-ocean ridge in the Indian Ocean, with a total length of about 17000 km and a width of about 1500 ~ 2000 km, accounting for about13 of the ocean width. It covers an area of 22.28 million square kilometers, accounting for 1/4 of the Atlantic Ocean floor. It is the most important and remarkable topographic unit of the Atlantic ocean floor. Mid-ocean ridges are S-shaped and consist of a series of narrow parallel ridges divided by faults. The top of the ridge is 2500 ~ 3000 meters away from the sea surface, and the peaks and ridges protruding from the sea surface become islands, such as Iceland, Azores, San Pedro-Sao Paulo Reef, Ascension Island, St. Helena, Tristan da Cunha and Bouvet Island. There is a longitudinal central valley in the middle ridge axis, which is generally 3000 ~ 4000m deep and10m wide. There are also longitudinal ridges on both sides of the central axis, and there are 12 ~ 40 km rifts between the ridges. An active seismic belt extends along the mid-ridge, especially along the central rift of the ridge axis, indicating that the mid-Atlantic ridge is an unstable geological structure. Mid-ocean ridges are also cut off and staggered by numerous transverse fault zones. The strike of the transverse fault zone is almost perpendicular to the mid-ocean ridge, and the topography shows deep linear grooves. Among them, the Romanche fault zone near the equator (the deepest Romanche trench is 7856 meters, located at 016' south latitude and18 35' west longitude) cuts the mid-ocean ridge into two sections, which are staggered by 65433. The northern section is called the Mid-Atlantic Ridge, which runs through the northern Atlantic Ocean, with a length of about 1.500km, the widest point of 1.500km, and the top of the ridge is about 2000-2500m away from the sea. The southern section is called the mid-Atlantic ridge, which runs through the southern Atlantic and is about 4500 kilometers long. The top of the ridge is 2000 ~ 3000 meters away from the ocean. The mid-Atlantic ridge is an integral part of the mid-Atlantic ridge.

Haishuichi

The relatively flat basin at the bottom of the Atlantic Ocean is divided into two rows of basins due to the middle ridge. From north to south, there are West Europa Basin, Iberian Basin, Canary Basin, Cape Verde Basin, Guinea Basin, Angola Basin and Cape Basin in the east. To the west are the North American Basin (located in the southeast of the sargasso sea), the Brazilian Basin and argentine basin. In addition, there is a vast Atlantic-Indian Ocean basin near Antarctica. The average depth of these basins is 4000 ~ 6300 meters, accounting for about 1/3 of the Atlantic ocean floor area. The deep-sea sediments in the Atlantic Ocean floor are mainly globigerina ooze and pterodactyl ooze, followed by diatom ooze, radiolarian ooze and red clay, which account for 80% of the total area of the ocean floor.

[Edit this paragraph] Climate characteristics

The Atlantic Ocean extends from north to south, and the equator passes through the middle. The climate is symmetrical from north to south, and the climate zone is complete. At the same time, influenced by ocean currents, atmospheric circulation, land and ocean contours and other factors, the climate in different sea areas is different. The equatorial belt of the Atlantic Ocean is a low-pressure area, and it is also the intersection of the north and south trade winds. The wind is weak and the direction is uncertain, so it is called windless area. At the same time, the updraft is strong, and there is a lot of convective cloud precipitation, with an annual precipitation of 2000 mm, which is a rainy area in the Atlantic Ocean. The subtropical zone is a high-pressure area, where the airflow is mainly subsiding and diverging, with less clouds and rain, sunny weather and strong evaporation. Generally, the precipitation is 500 ~ 1000 mm, and the annual precipitation in the high-pressure center (near the Azores in the eastern ocean) is only 100 ~ 250 mm, which is much less than the evaporation. It is a dry zone in the Atlantic Ocean. The air flow sinking from the subtropical high pressure area to the equatorial low pressure area is called the trade wind area, with the northeast trade wind in the northern hemisphere and the southeast trade wind in the southern hemisphere. The trade wind has a stable wind direction and a strong wind force (3 ~ 4), which has become an important wind belt in the Atlantic Ocean and is the driving force for the formation and maintenance of ocean surface current. The airflow sinking from subtropical high to subtropical low is called prevailing westerly belt, which is a powerful planetary wind belt at middle and high latitudes and the driving force for the formation of west wind drift at 40 ~ 60 degrees north and south latitudes. The westerlies also often merge with cold air from the polar regions. The formation of fronts and tornadoes leads to changeable weather and more precipitation, especially in winter, which often brings snowstorms, causing strong winds and waves in high latitudes, seriously affecting shipping, offshore fisheries and oil industry production. The high latitude sea area north of 60 in the northern hemisphere (mainly in the east) is affected by warm current and cyclone, and the annual precipitation can reach about 1000 mm; However, in the sea area south of 60 in the southern hemisphere, due to the adjustment of dry cold air and no warm current, the precipitation is very small, generally between100 ~ 250 mm.

The temperature distribution in the Atlantic Ocean is basically similar to that in the Pacific Ocean, extending along the latitude direction and decreasing from the equatorial region to the high latitude. The equatorial region has the highest temperature. The annual average temperature is 25 ~ 26℃, and the annual change of temperature is very small (generally not more than 3℃). Near 20 north latitude and 20 south latitude, the temperature in the hottest month is about 25℃, and that in Leng Yue is about 20℃. Near 40 north latitude, due to the influence of warm current, the temperature in the North Atlantic is higher than that in the South Atlantic, with the hottest month of 20℃, the South Atlantic is only 15℃, and Leng Yue is 13℃ and 10℃ respectively. The warming effect of the North Atlantic warm current is more obvious near the latitude of 60 north and south. The temperature in the hottest month is 10℃, while the temperature in the southern ocean is 0℃, and the temperature in the coldest month is 0℃ and-10℃ respectively, so the air in the North Atlantic is warmer than that in the South Atlantic. At the same time, due to the different effects of cold and warm air currents on the east and west coasts of the Atlantic Ocean, the temperature in the West Sea between 30 north and south latitudes is about 5℃ higher than that in the east. The temperature in the eastern part of the ocean north of latitude 30 is about 5 ~ 10℃ higher than that in the west, while in the south of latitude 30, due to the narrowing of land and the widening of sea area, and the influence of west wind drift, the temperature difference between the eastern and western parts of the Atlantic Ocean is not obvious.

The climate in the Atlantic Ocean is very different from north to south, and there are also differences between east and west. The annual temperature is not high, which is below 1℃ in the equatorial region, below 5℃ in the subtropical latitude region, below 10℃ in the northern latitude region and below 60℃ in the southern latitude region, only exceeding 25℃ in the northwest and southernmost part of the ocean. Northeastern trade winds prevail in the northern part of the Atlantic Ocean and southeast trade winds prevail in the southern part. The temperate zonal belt is located in the transition zone between cold and warm airflow and westerly belt, and the wind force is the largest. There are many storms between 40-60 degrees north and south latitude; From May to June, hurricanes often occur in the tropical areas of the northern hemisphere. The precipitation in the Atlantic Ocean is 500- 1 000 mm at high latitudes, 1 000- 1 500 mm at mid latitudes,1000 mm from east to west in subtropical and tropical regions, and over 2,000 mm in equatorial regions. The average sea surface temperature near the equator of the Atlantic Ocean is about 25-27℃, and it is colder in the east than in the west between 30 north and south latitude, but the opposite is true to the north of 30 north latitude. In the Atlantic Ocean, the summer ice floes in the southern hemisphere and the northern hemisphere can reach about 40 degrees north and south latitude respectively.

There is little change in the annual temperature in the Atlantic Ocean, and the annual temperature difference in the equatorial region is less than 65438 0℃. The subtropical zone is 5℃, the mid-latitude zone is 10℃, and only the northwest and extreme south exceed 20℃. The average temperature of seawater is 65438 07℃, which is slightly lower than that of the Pacific Ocean. Salinity is slightly higher than that in the Pacific Ocean, with an average of 35.4. In the North Atlantic, latitude 15? Between 30 and 30 is the subtropical high pressure area, and to the south is the northeast trade wind area. 40 north latitude? Between 60 degrees is the prevailing westerlies. In the South Atlantic, the tropical high pressure zone is located near 30 south latitude, and the prevailing westerly belt extends almost from 40 south latitude to Antarctica. At latitude 5? On the surface of the Atlantic Ocean, 20, 7? There were many hurricanes in June+10/October, 5438. There is often sea fog along the coast of Newfoundland in summer; In winter, the Atlantic coast of Europe is foggy; The southwest coast of Africa is foggy all the year round. The Atlantic Ocean current forms a circulation in the north and south. The northern circulation consists of the North Equatorial Warm Current, the Gulf Warm Current and the Canary Cold Current. The southern circulation warms from the southern equator. Brazil Warm Current, west wind drift and Benguela Current. The Gulf Stream is the most powerful warm current in the Atlantic Ocean and plays an important role in regulating the climate in northwest Europe.

[Edit this paragraph] Hydrological characteristics

The hydrological characteristics of the Atlantic Ocean have obvious regional characteristics. Under the direct action of atmospheric circulation, a huge anti-cyclone circulation system is formed in the south and north subtropical waters, with clockwise circulation in the North Atlantic and counterclockwise circulation in the South Atlantic. There is equatorial countercurrent in the sea area between the two circulation systems, which is opposite to the north-south trade winds from west to east. A complete sub-polar cyclone circulation is formed in the mid-latitude waters of the North Atlantic and the high-latitude waters of the South Atlantic respectively.

The Atlantic equatorial current is formed by the direct action of the north-south trade winds and flows from east to west on both sides of the equator. The Southern Equatorial Current flows westward from the coast of Africa at an average speed of 20-55km per day. When it reaches the Sanroque point in Brazil in South America, it is divided into two branches by the land "sharp corner": the Guiana Warm Current in the north and the Brazil Warm Current in the south. The thickness of the south branch is about 100 ~ 200m. It flows southward along the east coast of South America, near the La Plata River, joins with the Falklands Cold Current and enters west wind drift, then flows eastward at 42 ~ 48 to reach the southwest waters of Africa, and the mainstream continues to flow eastward with west wind drift; Another tributary flows northward along the west coast of Africa, forming a Benguela cold current with relatively thin width and thickness and slow flow rate, reaching near the equator in the north and merging with the South Equatorial Current, forming an anti-clockwise ocean current system in the South Atlantic. The Northern Equator flows from Cape Verde Islands and crosses the Atlantic Ocean at an average speed of 35-40 kilometers per day. It flows to the vicinity of the Lesser Antilles and is divided into two streams: one stream flows to the northwest along the north side of the archipelago, which is called the Antilles Warm Current; The other branch crosses the island and enters the Caribbean Sea, where it joins the Guyana Warm Current, which is called the Caribbean Warm Current. The Caribbean Warm Current enters the Gulf of Mexico from the Yucatan Strait and then flows out of straits of florida, which is called the Florida Warm Current. It flows near 35 north latitude and joins with the Antilles warm current, which is called the Mexican warm current. It flows northward along the east coast of North America, joins the Labrador cold current from north to near 40 north latitude, enters the westerlies and flows eastward, which is called the North Atlantic Warm Current. The warm current fanned out and flowed to the east coast of the Atlantic Ocean. The mainstream turns to the coast of western Europe and even northwest Europe, and then extends northeast to the Arctic Ocean. The other branch of the ocean flows southward, forming the Canary Cold Current along the northwest coast of Africa, and flows to Cape Verde Islands, where it divides into two branches, one of which merges with the northern equatorial current to form a clockwise ocean current system in the North Atlantic; The other branch continues to warm up southward and enters the Gulf of Guinea to form the Guinea Warm Current. The confluence of the warm current in Guinea and the equatorial countercurrent entering the Gulf of Guinea enhances the intensity of the warm current in Guinea, which makes there exist a thermal depression in the Gulf of Guinea all the year round, which is helpful to the formation and maintenance of the tropical monsoon.

The Mexican warm current, referred to as the Gulf Stream, is the most powerful warm current in the world's oceans. The section of the southeastern United States from straits of florida to Cape Hatteras is generally called the Florida Warm Current. The section from Cape Hatteras to 45 west longitude is called Gulf Stream, which means that the Gulf Stream is not in the Gulf of Mexico. From 45 west longitude to the east, it is called the North Atlantic Warm Current. The above three parts are collectively referred to as the Gulfstream System. In the Gulf Stream system, the warm current flowing out of straits of florida is 60-80 kilometers wide and 800 meters deep. The surface water temperature in the middle of the warm current reaches 30.5℃, and the water temperature in the depth of 10m is 27.5℃. The daily flow is 130- 150km, and the average hourly outflow of warm water is about 90 billion tons, which is about the total runoff of rivers in the world. After the warm current flows out of the Strait, a huge Antilles warm current joins in, and at the same time, the northeast trade wind keeps blowing warm current from Sargasso sea area to supplement it, resulting in an increasing amount of hot water, which makes the warm current have a huge warming effect on the sea area flowing northward to the North American continent, especially when it flows across the Atlantic to Western Europe and Northern Europe. It is estimated that the annual heat supplied to the Nordic 1 meter-long coast is equivalent to the heat generated by burning 60,000 tons of coal, which makes the temperature in the Norwegian coastal area in June, 5438+10/October 15 ~ 20℃ higher than that in the same latitude zone, so that some sea areas in the polar circle are not frozen and Murmansk Port becomes an ice-free port. The current flowing southward from the Arctic Ocean along the Labrador Peninsula is called Labrador Cold Current, which joins the Mexican warm current near 40 north latitude in the southeast of Newfoundland Island, resulting in frequent fog in this sea area, where warm-water fish and cold-water fish meet, forming a world-famous Newfoundland fishing ground. The Labrador cold current often brings huge icebergs or ice floes from the Arctic Ocean or Greenland, which not only lowers the seawater temperature, but also poses a serious threat to maritime shipping. South Atlantic sea ice is formed in the coastal waters of Antarctic continent, which can extend to the vast sea area south of 55 south latitude and even float to the vicinity of 40 ~ 35 south latitude. It is estimated that the amount of ice entering the Atlantic Ocean from the edge of the Arctic Ocean and the Antarctic continent reaches 900 cubic kilometers and 1600 cubic kilometers each year respectively.

The distribution and change of surface seawater temperature in the Atlantic Ocean are related to the distribution and change of air temperature. The water temperature is the highest in the equatorial region, with an annual average temperature of 25 ~ 27℃, which gradually decreases from the equator to high latitudes. The annual variation of water temperature in equatorial waters is the smallest, generally between 65438 0 ~ 3℃, and increases to 5 ~ 8℃ between 30 ~ 50 north latitude and 30 ~ 40 south latitude, while the annual variation in high latitude waters is slightly smaller, about 4℃ near Arctic waters and only about 65438 0℃ in Antarctic waters. However, the annual variation of surface water temperature can reach more than 65438 00℃ in local sea areas which are obviously affected by continental climate seasonal variation or cold, warm current, front and other factors. Generally speaking, the north and south ends of the Atlantic Ocean are open, which is obviously affected by the cold water and floating ice in the Arctic Ocean and Antarctic waters, so the average surface water temperature is only 16.9℃, which is lower than that in the Pacific Ocean and the Indian Ocean.

The average salinity of Atlantic surface water is 35.9‰. In subtropical waters, due to strong evaporation and little precipitation, the salinity is as high as 37.3‰, especially in the trade winds in the southwest of Azores, with an average salinity of 37.9‰, and the annual average of coastal waters in Brazil between south latitude10 ~ 20 is also 37.6‰. Because the annual precipitation in equatorial waters is greater than the annual evaporation, the salinity drops to about 35.0‰. Ocean surface current also affects salinity distribution. For example, the Gulf Stream and the North Atlantic Warm Current transport high-salinity seawater to the east side of the ocean at high latitudes, while low-salinity seawater (below 34) is transported to the west side of the ocean, so the salinity of surface seawater on the east side of the Atlantic at high latitudes is higher than that on the west side. In west wind drift, south of 45 south latitude, the isoline of surface seawater is almost parallel to the latitude circle.

Because the two continents are inclined to it, it accepts the flow direction of a large part of the rivers in the world, such as the St. Lawrence River, the Mississippi River, the Orinoco River, the Amazon River, the La Plata River, the Congo River, the Niger River, the Loire River, the Rhine River, the Elbe River, and the Mediterranean Sea and the Baltic Sea. Therefore, the basin area of the Atlantic Ocean (including the Arctic Ocean) is 43,229,700 square kilometers, almost four times that of the Pacific Ocean and just four times that of the Indian Ocean.

ocean current

The Atlantic ocean current forms a north-south circulation system: the northern circulation runs clockwise and consists of the North Equatorial Warm Current, the Antilles Warm Current, the Gulf of Mexico Warm Current and the Canary Cold Current, among which the Gulf of Mexico Warm Current extends to the North Atlantic Warm Current and goes deep into the Arctic Ocean; The circulation in the south is anticlockwise, which consists of the South Equatorial Warm Current, the Brazil Warm Current, the west wind drift and Benguela Cold Current. There is an equatorial countercurrent between the two circulations, which reaches the Gulf of Guinea from west to east and is called the Guinea Warm Current.

[Edit this paragraph] Marine resources

The Atlantic Ocean is rich in marine resources, and the resources that have been developed and utilized are mainly mineral resources and aquatic resources.

The mineral resources in the Atlantic mainly include oil, natural gas, coal, iron, heavy sand and manganese nodules. There are two oil and gas belts in the marginal basins on both sides of the Atlantic Ocean, namely the East Atlantic Belt and the West Atlantic Belt. The western Atlantic oil and gas belt mainly includes: ① the submarine oil field of Lake Maracaibo in northern Venezuela and the oil field of the Gulf of Paria between Venezuela and Trinidad. The proven reserves are 4.02 billion tons and the natural gas is 862.4 billion cubic meters. In recent years, the annual output of oil fields is nearly 654.38 billion tons; 5 billion cubic meters of natural gas. ② Offshore oil fields in the Gulf of Mexico are mainly distributed in bay of campeche in the southwest and along the coasts of Texas and Louisiana in the United States. Among them, bay of campeche has proven oil reserves of nearly 5 billion tons (1978), and the continental shelf area of the Gulf of Mexico, which belongs to the United States, has oil reserves of 2 billion tons and natural gas reserves of 360 billion cubic meters. The East Atlantic oil and gas belt includes: ① North Sea continental shelf oil field, with proven reserves of more than 4 billion tons and natural gas of 3 trillion cubic meters (1977). In recent years, the annual output of oil has reached over 654.38 billion tons, and the annual output of natural gas is nearly 654.38 billion cubic meters. The exploitation of Beihai Oilfield has greatly improved the energy conditions of Nordic countries. However, there are many storms and rainy days in the North Sea in autumn and winter, which brings difficulties to offshore drilling and exploitation and increases the cost of oil production. (2) The offshore oil area in the Gulf of Guinea is dominated by Nigeria, with oil reserves of about 2.6 billion tons. In addition, oil and gas resources have also been found on the offshore continental shelf of Canada, Brazil and Argentina on the west coast of the Atlantic Ocean, and some of them have been put into production.

Seabed coal is mainly distributed in the offshore of Scotland in northeast England and the continental shelf outside Nova Scotia Peninsula in Canada. Britain's seabed coal reserves are not less than 550 million tons, and the annual coal mining capacity is 20-25 million tons. In addition, coal deposits have also been found in the coastal seabed of Spain, Turkey, Bulgaria, Italy and other countries. On the east side of Newfoundland Island in North America and Canada, there is the world's largest submarine iron mine. The estimated reserves exceed 2 billion tons and have been mined. There are also submarine iron mines in the Baltic Sea and the Gulf of Finland. There are also a large number of sand mines in the Atlantic Ocean, which are distributed along the coasts of the United States, Brazil, Argentina, Norway, Denmark, Spain, Portugal and Senegal. Manganese nodules are widely distributed at the depth of 4,000-5,000 meters in the Atlantic Ocean, with a total reserve of about 65.438+0 trillion tons, mainly distributed in the North American basin and the bottom of argentine basin, and the enrichment degree and grade are not as good as those in the Pacific Ocean and the Indian Ocean.

The Atlantic Ocean is rich in biological resources, mainly fish, and its catch accounts for about 90% of the catch of marine life in the Atlantic Ocean. The catch of the Atlantic Ocean once ranked first among the world's oceans, and after the 1960s, it was lower than that of the Pacific Ocean, ranking second. However, the catch per unit area reached 250kg/km2, ranking first in the world. The largest catch is in the northeast sea, that is, around the North Sea, the Norwegian Sea and Iceland. The annual catch accounts for about 45% of the total catch in the Atlantic Ocean, the average output per unit area is 830 kg/km2, and the continental shelf area is about 1.200 kg/km2. Followed by the northwest Atlantic, the catch accounts for 20% of the total catch, and the average catch per unit area is 690 kg/km2. Among them, Newfoundland, the United States and Canada produce 1.500 kg/km2 per unit area on the East Continental Shelf, which is the fishing ground with the highest ocean yield in the world. In addition, the Caribbean, the Bay of Biscay, Angola and Namibia are also important fishing areas. The Atlantic Ocean near Antarctica is an important fishing area for krill and whales. The main fish caught in the Atlantic Ocean are herring, northern cod, hairscales, long-tailed cod, flounder, tuna, salmon, horse sole, sea bass and so on. These fish are mainly distributed in the continental shelf and the continental shelf area near the island. In open waters, especially tropical waters, there are sail fish and flying fish. The coastal areas of western Europe and North America are rich in oysters, mussels, sea fans, crayfish and crabs. At present, some countries along the Atlantic coast are actively developing artificial culture of mollusks such as mussels and sand.

There are five biota in the Atlantic Ocean, which are composed of water layers. From the ocean surface to the ocean floor is: 1. Coastal benthic zone, the maximum depth is less than 60 meters, including all kinds of coastal animals and most algae; 2. Bright zone, the maximum depth of which is within180m, belongs to the part where sunlight can shine, and the creatures inhabiting this zone include a large number of zooplankton, which provide 90% nutrients in the ocean; 3. Medium-deep zone with a depth of 200? 900 meters, is the living area of sperm whales and squid; 4. abyssal zone, depth 900? 4000 meters, is a dark area, is the habitat of luminous animals; 5. Benthic zone, the depth of which is below 4000m, is inhabited by primitive animals.

fishery

Lobster fishing in Cape Breton, Nova Scotia, Canada

Rich in marine resources, Newfoundland and Beihai in the northwest and northeast are the main fishing grounds, rich in herring, cod, sardines, mackerel, hairscales and so on. Others include oysters, mussels, crayfish, crabs and various algae. The marine catch accounts for about 1/3-2/5 of the world. Whales, seals and krill are produced near the Antarctic continent, and the catch of marine animals is also very large.

The Atlantic Ocean occupies more than half of the world's fishing grounds. High-yield areas are along the coasts of North America and South America. On the coast of Newfoundland, where the Gulf Stream meets the Labrador Current, it is the richest fishing ground in the world. Overfishing in the second half of the 20th century led to the shortage of fish in several traditional fishing grounds, especially in the North Atlantic. There are abundant manganese nuclei in the ocean. There are a lot of diamond placers on the seabed along the southwest coast of Africa. The North Sea and the Gulf of Mexico are rich in oil and natural gas. There is a small amount of coal and tin near the British Isles. 70% of the world's bromine production comes from Atlantic seawater.

mineral

The Caribbean Sea, the Gulf of Mexico, the North Sea, the Gulf of Guinea and the Mediterranean Sea are all rich in submarine oil and natural gas.

[Edit this paragraph] Traffic

The Atlantic Ocean plays an extremely important role in world shipping. It is connected to the Panama Canal and the Pacific Ocean in the west, the Strait of Gibraltar in the east, the Indian Ocean via the Mediterranean Sea and Suez Canal, the Arctic Ocean in the north and the Antarctic waters in the south. The routes extend in all directions and are very convenient. At the same time, the Atlantic coast is almost all the most developed regions on all continents and capitalist countries with high economic level, with frequent trade and economic exchanges, which is an important link and hub in the world's global shipping system. Among the more than 2,000 ports in the world, the Atlantic coast accounts for 3/5, many of which are world-famous ports. There are more than 4,000 ships on the North Atlantic route every day, accounting for 2/3 of the world's cargo turnover and 3/5 of the cargo throughput. It is the most developed ocean in the world. There are five main routes: ① North Atlantic route between Europe and North America. (2) the Far East route between Europe and Asia and Oceania. ③ Mid-Atlantic route between Europe and the Gulf of Mexico and the Caribbean. (4) the South Atlantic route between Europe and South America. ⑤ The route from Europe to Cape Town along the Atlantic coast of Africa. Among them, the North Atlantic route is the busiest, and more than 1/3 merchant ships in the world sail on this route. The main goods transported by sea are petroleum and petroleum products, followed by iron ore, grain, coal, bauxite and alumina. The main coastal ports are Gdansk, Hamburg, Rotterdam, Antwerp, London, Liverpool, le havre, Marseille, Genoa, Trieste, constanta and Odessa. Alexandria, Darbeda (Casablanca), Monrovia, Halcott Port and Cape Town in Africa; New york, Philadelphia, Baltimore, Norfolk, Tampa, New Orleans and Houston in North America; Maracaibo, Tubaran, Rio de Janeiro and Buenos Aires in South America. Rotterdam is the largest seaport in the world with an annual throughput of 300 million tons. In 1970s, the total length of submarine cables in the North Atlantic was 200,000 kilometers, of which 16 cables connected Western Europe and North America. The Atlantic Ocean is the main road connecting Western Europe, North America, South America and Africa.

shipping

Atlantic shipping is developed, and east and west are connected with Indian Ocean and Pacific Ocean through Suez Canal and Panama Canal respectively. Seagoing ships can sail all year round, and about 75% of the world's seaports are located in this sea area. Europe and North America mainly have North Atlantic routes; Far East routes between Europe, Asia and Oceania; The mid-Atlantic route between Europe and the Gulf of Mexico and the Caribbean; South Atlantic route between Europe and the Atlantic coast of South America; The route from western Europe to Cape Town along the Atlantic coast of Africa. The total length of the Atlantic submarine cable is over 200,000 kilometers. The line from the northwest end of Valencia Island in Ireland and Brittany Peninsula in France to the southeast end of Newfoundland Island in Canada, or all the way to the northern end of Nova Scotia Peninsula in Canada, is the main trunk line of the Atlantic submarine cable.

The shipping industry in the Atlantic Ocean is extremely developed. West across the Panama Canal between China and the United States, directly to the Pacific Ocean; You can also bypass Cape Horn at the southern tip of South America, cross the Drake Strait or strait of magellan, and reach the Pacific Ocean. In the east, it crossed the Strait of Gibraltar into the Mediterranean Sea, crossed the Suez Canal through the Red Sea, and took a shortcut to the Indian Ocean. You can also bypass the Cape of Good Hope at the southern tip of Africa and enter the Indian Ocean. The connection between the Atlantic Ocean and the Arctic Ocean is more convenient than other oceans, and there are many waterways connecting them. There are many international routes in the Atlantic Ocean, connecting Europe, America and coastal countries in Africa, and the cargo volume ranks first in all oceans. Especially in the North Atlantic. The Dover Strait and the English Channel, which connect the Atlantic Ocean and the North Sea, are the busiest places in the world. There are many ports along the Atlantic coast, mainly including Boston, new york, Baltimore, New Orleans, Havana, Amsterdam, Copenhagen and Venice.

[Edit this paragraph] Human geography

The origin of the Atlantic Ocean and its influence on China.

Atlantic Ocean: The word Daxi comes from the name of Atlas, the Hercules in ancient Greek mythology. It is said that Atlas lives in the Atlantic Ocean, can know the depth of any ocean, and has the power to stand on the earth. 1845, the Atlantic Ocean was named by the Geographical Society of London.

"Atlantic" is not a translated name, but an authentic domestic and foreign place name! Since the Ming Dynasty, China has always taken Leizhou Peninsula to Kalimantan as the boundary when expressing its geographical position, with the East China Sea to the east and the West Sea to the west. This is why we often call the Japanese easterners and the Europeans westerners. In Ming Shenzong, Matteo Ricci came to China to visit Emperor China. In China's way, he said he was an "Atlantic" man on the west side of "Little Western Ocean (as China said at that time)". It can be seen that at that time, we called the Atlantic Ocean "Atlantic Ocean", and there was no other translation of this name.

The English name of the ATLANTICOCEAN is Atlantic Ocean, which was called OCEAMUSATLANTICUS in ancient times. It is named after Atlas, the Hercules in ancient Greek mythology. Atlas can know the depth of any ocean and support pillars to separate heaven and earth. Legend has it that the Atlantic Ocean is where he lives. At first, the Greeks named the mountains in northwest Africa after the god Aras, and later they extended to the ocean outside Gibraltar. This name was quoted by the Dutch geographer Berthard Vasini (1622- 1650) in 1650.

The Chinese name "Atlantic" was first recorded in the Ming Dynasty. In the Ming Dynasty, it was customary to divide things from Leizhou Peninsula to kalimantan island, with "West" in the west and "East" in the east. So China used to call Europeans "Westerners" and Japanese "Orientals". At the end of Ming Dynasty, with the increase of geographical knowledge in Europe, the Indian Ocean was renamed "Little Western Ocean" and the sea west of Europe was called "Atlantic Ocean". After the introduction of western geography and maps, translators found it difficult to translate the word Atlantic into suitable Chinese, so they used to translate it into "ATLANTICOCEAN", which has been in use ever since.

The Atlantic War.

Normandy landing, Jutland naval battle, Dunkirk retreat.

other

Most seamounts in the Atlantic Ocean are hidden below 3000 meters, and only a few ridges protrude from the ocean surface to form islands. Most of the islands are concentrated in the northwest of the Caribbean. Columbus mistook North America for India, so he gave them a very inappropriate name "West Indies". Legend has it that the bottom of the Atlantic Ocean is an ancient Atlantis civilization.

The peculiar "S"-shaped coastline of the Atlantic Ocean also inspired German meteorologist Wei Gena to boldly put forward the famous theory of continental drift.

In the North Atlantic, there is also a clockwise circulation, which consists of the North Equatorial Current, the Gulf Warm Current, the North Atlantic Warm Current and the Canary Cold Current. Among them, the Gulf Stream is the largest warm current in the world, and its flow is equivalent to 120 times of the total flow of rivers in the world. Like a huge heating pipe, it supplies huge heat and makes the climate in northwest Europe warm as spring. The circulation in the South Atlantic is counterclockwise, which consists of the South Equatorial Current, the Brazilian Warm Current, the west wind drift and the Benguela Cold Current. Most of the tides in the Atlantic Ocean belong to semidiurnal tides. On the open ocean, the tidal range is not obvious; In nearshore or narrow bays, the tidal range is very large. The tidal range in Bristol Bay on the south coast of Britain is as high as 1 1 m, and that in Fendi Bay in North America is as high as 2 1 m.. The tidal bore in the mouth of Amazon River in South America is even more spectacular than that in Qiantang River in China.