Climate
South America is the most wet continent Earth and not as hot as Africa. Part South America located in temperate climatic zone. Unlike Africa, all climatic zones, except the subequatorial one, replace each other only when moving south of the equator. In general, the climate of South America is more diverse than that of Africa. Average monthly temperatures in most of the continent range from +20 to +28 C. However, sometimes waves of cold air invade the mainland from the south, and on the plains of Patagonia frosts reach -35 C. Large differences are observed in humidification conditions. Precipitation on the mainland is distributed unevenly.
The southern part of the continent is located in a temperate climate zone. The climate here is especially contrasting. On west coast it is marine and temperate. Winter is relatively warm, with temperatures of +4-6 C, with cloudy, windy weather, and summer is humid, cool, with frequent rains at an air temperature of +8-10 C. Precipitation falls more than 2000 mm per year. In the eastern part of the belt, the climate is continental temperate with cool winters with little snow and dry warm summer. However, even in summer snowstorms occur here - the breath of the nearby Antarctic takes its toll.
The Andean highland climate is varied. Its main feature is the change as it rises from the foothills to the peaks and as it moves from north to south near the equator in the lower belt of the Andes, the climate on the eastern and western slopes is equatorial, and on the peaks there are snow and glaciers. The climate is especially harsh in tropical zone on the central plateaus of the Andes, where the air is exceptionally clean and dry. Precipitation here falls mainly in the form of snow even in summer, but it is very small. These highlands are the driest and most barren in the world. Thin air, scorching rays of the sun, hurricane winds, characteristic features weather, which changes sharply and more than once here during the day. A person can hardly tolerate such a high-mountain climate.
In general, the climate of South America, which is characterized by an abundance of heat and moisture over most of the territory, creates favorable conditions for year-round vegetation of plants. On the mainland you can cultivate all tropical crops and harvest several harvests a year. However, it often happens here natural disasters: after prolonged rains, rivers overflow their banks, flooding fields, villages and roads. In the center of the continent there are frequent droughts, and sometimes unexpected cold weather occurs.
For the population of South American countries, these natural disasters are especially severe; there are not enough funds for quick recovery normal life.
Inland waters
Since South America is the wettest continent on earth, it is not surprising that nature created the largest river basin world with the grand Amazon. The area of the river basin is almost equal to the entire Australia. The rise of water in the northern and southern tributaries of the Amazon occurs in different time of the year. This somewhat smoothes out fluctuations in the level of the Amazon, so it is full of water all year round. When the water rises, the river floods vast areas, forming impassable swamps.
The Amazon channel in the middle reaches reaches a width of 5 km, in the lower reaches - 80 km, and at the mouth its width reaches 320 km, so opposite bank impossible to see. The mouth of the river -1 is cleared of sediment sea tides and low tides, which are noticeable on the river for 1,400 km from the mouth.
The waters of the Amazon are rich in life. In quiet creeks and channels, the Victoria Regia water lily grows with floating leaves up to 2 m in diameter. Among the fish, the most famous are predatory piranhas, electric eels, sharks, and the commercial fish piraruca, 4 m long. The river is home to caimans (a type of crocodiles), as well as mammals - freshwater dolphins. Is it any wonder that such a mighty and immense river has given rise to many legends and myths, about which many interesting books have been written.
Paraná and Orinoco, unlike the Amazon, have a pronounced seasonality. With the arrival of humid equatorial air and the rainy season, rivers overflow and flood the surrounding flat areas, turning them into vast swamps. During the dry season, rivers become very shallow. There are many rapids and waterfalls on the rivers flowing from the Andes, Guiana and Brazilian plateaus. Particularly famous is the Iguazu Falls, located on one of the tributaries of the Parana. Its roar can be heard 20-25 km away. The river breaks into 300 streams and streams, separated by rocky islands with dense vegetation. This is one of the most beautiful waterfalls on Earth. On one of the tributaries of the Orinoco, flowing down from the Guiana Plateau, is the highest waterfall in the world - Angel Falls with a height of 1054 m.
There are few large lakes on the mainland. The most big lake- Maracaibo lies in the north in a depression earth's crust and is connected by a narrow channel to the bay Caribbean Sea. Oil is extracted along the shores and from the bottom of the lake. Lake Titicaca, the largest alpine lake in the world, is located in the Andes. Its banks are densely overgrown with reeds, from which the Indians knit their light and elegant rafts.
The rivers of South America play big role in the life of the population. On low-lying plains they are navigable. Power plants are built on fast-flowing rivers. In dry areas, water is used to irrigate fields.
The spaces contribute to the formation of large and deep rivers on the mainland. Under the influence of humid climates, South America receives twice as much precipitation as the average of the entire landmass of the Earth. River flow is also almost twice as high as the global average. Accounts for 8% of land and 14% of runoff globe. Thus, South America is richer than other continents in water resources.
Among the rivers of the mainland, it especially stands out - the deepest river on the globe and the largest in terms of basin area (more than 7 million km2). The length of the Amazon, if taken as the source of the river. Marañon will be 6437 km. The Amazon is the second longest river in the world after. However, unlike the Nile, the Amazon has many tributaries - over 500; 17 of them have a length from 2000 to 3500 km; more than 100 are navigable. The width of the Amazon channel after the confluence of the Marañon and Ucayali rivers is 1-2 km; near the city of Manaus it reaches 5 km, in the lower reaches - 20 km; and at the mouth the width of the main channel of the Amazon is 90 km with a depth of 70 m. The river is navigable over a long distance. Ocean-going ships travel up the river approximately 1,700 km to the city of Manaus.
The Amazon receives tributaries from the northern and southern hemispheres. Since the right tributaries experience high water in October-March, and the left ones in April-October, the Amazon is full of water throughout the year. The maximum flood occurs at the end of summer in the southern hemisphere (March-April), since the right tributaries are larger and more abundant than the left ones. At this time, the level in the river rises by 10-15 m and it floods vast areas. The average annual flow of the Amazon is 5000 km 3, which is the majority of the flow of all South America and 15% of the flow of all rivers on the globe.
And the Orinoco is also a large and high-water river of the mainland. Unlike the Amazon, they have a pronounced seasonality of flow. The water level on these rivers rises in the summer season, and in winter they become very shallow. The rivers and their tributaries in the upper reaches flow along the slopes of the Brazilian and. Here they have many rapids and waterfalls. On one of the tributaries of the Orinoco (Churun River) there is the highest in the world - 1054 m. It is grandiose and is very famous on one of the tributaries of the Parana River.
South America is poor in lakes. The most famous lake mainland - Titicaca. This is the largest of the alpine lakes in the world. It is located at an altitude of 3812 m above sea level. Lake area - 8300 km2, maximum depth— 304 m.
Along the shores Atlantic Ocean there are large lakes - lagoons. The most significant of them is Lake. Maracaibo, connected to the Gulf of Venezuela. Many lagoons have lost connection with the ocean (for example, Lake Patus).
Since South America receives more precipitation than any other continent in the world, a huge number of rivers have formed here. This is why the deepest river on our planet is located here. Amazon is entirely inequatorial beltSouth America. And thanks to its huge area on the mainland, it collects as much water from its basin as no other river on Earth. The Amazon is more than ahead of the deepest river in terms of amount of water. Eastern Hemisphere- Congo. Water flow in the lower reaches of the Amazon reaches 220 thousand m3/s. If we measure the length of this river not from the confluence of the Marañon and the Ucayali, but from the source of the Ucayali in the Andes, then the Amazon will also become the most long river on the planet. When it flows into the Atlantic Ocean, the Amazon forms the largest delta in the world. The river remains full all year, although the water level varies somewhat, this is due to the overflow of the tributaries that feed the Amazon. Many tributaries of the Amazon have their origins already insubequatorial climateskom belt. However, the left tributaries belong to the Northern, and the right – to the Southern Hemispheres, therefore their floods alternate. With the arrival of the rainy season to the north in June-August, the left tributaries are filled with water, and in December-February, the rainy season comes to the Southern Hemisphere, since now the wetequatorial airmassfollowing the onset of summer. Tributaries carry a huge amount of water into the Amazon, it is replenished from falling rains and from melting glaciers. An interesting place is where the Rio Negro River flows into the Amazon. The Rio Negro gets its name from the dark color of the water. The water from it, at the confluence with the Amazon, does not mix for several kilometers and continues to flow in the form of a separate dark stream (in the Photo).
Another very large river of the mainland is the Parana River. Its source is located on the Brazilian plateau, it flows south through the subequatorial, tropical and subtropical zone mainland, flowing into the Gulf of La Plata. The river's flooding is also associated with the rainy season and the melting of glaciers in the Andes, which feed its many tributaries. Therefore, the Paraná flood occurs during summer months Southern Hemisphere - December-February. In contrast, another river flows in the north of South America - the Orinoco. Despite the fact that its overflow is also confined to the summer, due to its location in the Northern Hemisphere, it overflows in June-August.
A peculiarity of the location of the rivers of South America is that all large rivers belong to the Atlantic Ocean basin. This is due to the fact that the watershed of the Atlantic and Pacific Ocean passes through the Andes, which are located near the Pacific coast. For this reason, the formation of large rivers flowing into the Pacific Ocean is impossible.
Lakes in South America are few in number. There are no very large lakes here. The largest lakes in area are Lakes Titicaca and Maracaibo. Titicaca is the highest navigable lake in the world. The water in it is always quite cold due to the fact that it is located on high altitude. The Desaguadero Titicaca River connects with another, also high-mountain, drainless lake Poopo. Lake Maracaibo (pictured) is located in the north of the mainland; through a narrow and shallow strait it is connected to the Gulf of Venezuela and the Caribbean Sea, however, it is considered a lake. Exactly this large lake In South America. Its name translates as “Land of Mara” - a local leader during the colonization of the mainland. Now the lake plays a very important role in the economy of Venezuela, since huge volumes of oil are produced here, which remains the most important source of income for this country. Location on the shores of the lake a large number of oil towns. A real miracle of nature in these places is the “Catatumbo lightning”. In the place where the Catatumbo River flows into Lake Maracaibo, lightning strikes 1.2-1.6 million times a year, that is, from 140 to 160 days a year, almost continuously for 7-10 hours per night. This is unique a natural phenomenon and to this day it is a real lighthouse of Lake Maracaibo, serving for all ships, because lightning can be seen from 400 kilometers away! The phenomenon is explained by the collision of air currents from the Andes with rising methane from local swamps, which forms a strong potential difference on the clouds, which is constantly discharged in the form of celestial electricity.
Inland waters of South America
The features of the relief and climate of South America predetermined its exceptional wealth of surface and groundwater, a huge amount of flow, the presence of the deepest river on the globe - the Amazon. Occupying 12% of the Earth's land area, South America receives approximately 2 times more (1643 mm) average precipitation per unit of total area. The rivers between the ocean basins are also extremely unevenly distributed: the Pacific Ocean basin is 12 times smaller than the Atlantic basin (the watershed between them runs mainly along the Andes ridges); in addition, about 10% of the territory of South Africa belongs to the area of internal drainage. Rivers are predominantly fed by rain; in the far south, they are also fed by snow and glaciers.
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A large amount of precipitation brought from the Atlantic, extensive plateaus, gently sloping down to huge lowlands and plains that collect runoff from the adjacent slopes of the Andes, contributed to the formation of large river systems in the east of South Africa: the Amazon, Orinoco, Parana and Paraguay. Uruguay; in the Andes the largest is the river system. Magdalena flowing in a longitudinal depression of the humid Northern Andes. Only lowland rivers are suitable for navigation. Mountain rivers of the Andes and plateaus, replete with rapids and waterfalls (Angel, 1054 m, Caietur, 226 m, Iguazu, 72 m, etc.), as well as deep watercourses of constantly wet plains, have enormous hydroelectric potential (over 300 million kW).
Large lakes, mainly of glacial origin, are concentrated mainly in the Patagonian Andes (Lago Argentino, Buenos Aires, etc.) and in southern Central Chile (Llanquihue, etc.). IN Central Andes lies the highest mountain of the Earth's large lakes - Titicaca, there are also many residual lakes (Poopo and others) and large salt marshes; the latter are also typical for the depressions between the Pampinsky sierras (Salinas Grandes and others). Large lagoon lakes are located in the north - Maracaibo and in the southeast of SA - Patus, Lagoa-Mirin.
The most big rivers South America
Name |
Length in m |
Basin area in thousand km |
Amazon (with Ucayali) |
6437 |
7047 |
Amazon (with Marañon) |
5500 |
|
Paraná (with Rio Grande and La Plata Estuary) |
4876 |
3100 |
Madeira (with Mamore) |
3350 |
1200 |
Jurua |
3283 |
|
Purus |
3211 |
|
San Francisco |
2914 |
|
Zhapura (with Kaketa) |
2816 |
|
Orinoco |
2736 |
|
Tocantins |
2699 |
|
Araguaia |
2627 |
|
Paraguay, river |
2550 |
|
Rio Negro |
2253 |
|
Uruguay, river |
1609 |
|
Magdalena |
1538 |
Amazon river
The largest river in South America is the Amazon. Most of its basin is located south of the equator. The area of this largest river basin in the world is over 7 million km2, the length of the river from the main source (the Marañon River) is 6400 km. If we take Ucayali and Apurimac as the source of the Amazon, then its length reaches 7194 km, which exceeds the length of the Nile. The water consumption of the Amazon is several times higher than that of all largest rivers peace. It is equal to an average of 220 thousand m 3 /s (the maximum flow rate can exceed 300 thousand m 3 /s). The average annual flow of the Amazon in its lower reaches (7000 km 3) accounts for most of the flow of all South America and 15% of the flow of all rivers on Earth!
The main source of the Amazon - the Marañon River - begins in the Andes at an altitude of 4840 m. Only after merging with the first major tributary - the Ucayali - within the plain the river receives the name Amazon.
The Amazon collects its numerous tributaries (more than 500) from the slopes of the Andes, Brazilian and Guiana highlands. Many of them exceed 1500 km in length. The most numerous and major tributaries The Amazons are rivers of the southern hemisphere. The largest left tributary is the Rio Negro (2300 km), the largest right tributary, and the largest tributary of the Amazon, is the Madeira (3200 km).
Some of the tributaries, eroding clay rocks, carry very muddy water (“white” rivers), others, with clear water, - dark from dissolved organic substances (“black” rivers). After the Rio Negro (Black River) flows into the Amazon, light and dark waters flow in parallel, without mixing, for about 20-30 km, which is clearly visible on satellite images.
The width of the Amazon channel after the confluence of Marañon and Ucayali is 1-2 km, but downstream it quickly increases. Near Manaus (1690 km from the mouth) it already reaches 5 km, in the lower reaches it expands to 20 km, and at the mouth the width of the main channel of the Amazon, together with numerous islands, reaches 80 km during the flood. In the western part of the lowland, the Amazon flows almost at the level of the banks, without actually having a formed valley. In the east, the river forms a deeply incised valley, which presents a sharp contrast with the watershed areas.
The Amazon Delta begins approximately 350 km from the Atlantic Ocean. Despite its ancient age, it did not move into the ocean beyond its original shores. Although the river carries huge masses hard material(on average 1 billion tons per year), the process of delta growth is hampered by the activity of tides, the influence of currents, as well as the subsidence of the coast.
In the lower reaches of the Amazon, the ebb and flow of the tides have a great influence on its regime and the formation of the banks. Tidal wave penetrates upstream for more than 1000 km, in the lower reaches its wall reaches a height of 1.5-5 m. The wave rushes against the current with enormous speed, causing strong excitement on sandbanks and banks, destroying the banks. U local population this phenomenon is known as "pororoka" and "amazunu".
The Amazon is full of water throughout the year. Twice a year the water level in the river rises to a significant height. These maximums are associated with rainy periods in the northern and southern hemispheres. The highest flow in the Amazon occurs after the rainy period in the southern hemisphere (in May), when the bulk of the water is carried by its right tributaries. The river overflows its banks and in its middle reaches floods a vast area, creating a kind of giant internal lake. The water level rises by 12-15m, and in the Manaus area the width of the river can reach 35 km. Then comes a period of gradual decrease in water flow, the river enters the banks. The lowest water level in the river is in August and September, then there is a second maximum associated with the period of summer rains northern hemisphere. In the Amazon it appears with some delay, around November. The November maximum is significantly lower than the May one. In the lower reaches of the river, two maxima gradually merge into one.
From its mouth to the city of Manaus, the Amazon is accessible to large ships. Vessels with a fairly deep draft can penetrate even as far as Iquitos (Peru). But in the lower reaches, due to the tides, the abundance of sediments and islands, navigation is difficult. The southern branch, Para, which has a common mouth with the Tocantins River, is deeper and more accessible to ocean-going ships. It is home to the major ocean port of Brazil - Belém. But this branch of the Amazon is now connected to the main channel only by small channels. The Amazon with its tributaries is a system waterways communications with a total length of up to 25 thousand km. Transport value the river is large. For a long time she was the only way, connecting the interior of the Amazonian lowland with the Atlantic coast.
The rivers of the Amazon basin have large reserves water energy. Many tributaries of the Amazon, when entering the lowlands, cross the steep edges of the Brazilian and Guiana highlands, forming large waterfalls. But these hydro resources are still very little used.
Rivers Parana and Uruguay
The second largest river system in South America includes the Parana and Uruguay rivers, which share a common mouth. The system received its name (La Plata) from the giant estuary of the same name in Parana and Uruguay, reaching 320 km in length and 220 km in width at the mouth. The basin area of the entire system is more than 4 million km 2, and the length of the Parana, according to different sources, ranges from 3300 to 4700 km. The sources of the Paraná - Rio Grande and Paranaiba - are located in the Brazilian Highlands. Many other rivers of the system also begin there. All of them have rapids in their upper reaches and form several large waterfalls. The largest waterfalls are Guaira with a height of 40 m and a width of 4800 m on the Parana and Iguazu with a height of 72 m on its tributary of the same name. A network of hydroelectric power stations has been created on them.
In its lower reaches, the Paraná is a typical lowland river. The main maximum flow occurs in May due to summer rains in the Brazilian Highlands. The navigable importance of the rivers of the La Plata system and La Plata itself is very great.
Orinoco River
The third largest river in South America is the Orinoco. Its length is 2730 km, the basin area is over 1 million km2. The Orinoco originates in the Guiana Highlands. Its source was discovered and explored by a French expedition only in 1954. The Casiquiare Orinoco River connects with the Rio Negro, a tributary of the Amazon, where part of the water of the upper Orinoco flows. This is one of the most significant examples of river bifurcation on Earth. When it flows into the Atlantic Ocean, the river forms a large delta, the length of which reaches 200 km.
The water level in the Orinoco depends entirely on the rainfall that falls in the northern part of its basin in the summer (from May to September). The maximum for the Orinoco, which occurs in September-October, is very pronounced. The difference between summer and winter water levels reaches 15 m.
Lakes
Lakes in South America are few and far between. The main genetic groups of continental lakes are tectonic, glacial, volcanic, and lagoonal. There are small glacial and volcanic lakes in different parts Andes. The largest glacial and glacial-tectonic lakes are concentrated in the west of the Southern Andes.
The largest lake on the mainland is Titicaca - located on the Andean plateau at an altitude of more than 3800 m, on the border between Peru and Bolivia. Its area is 8300 km 2, and its maximum depth is 281 m. There are terraces on the shores of the lake, indicating a repeated decrease in its level. The lake has a drainage into another, shallower tectonic lake - Poopo . The water in Lake Titicaca is fresh, while in Poopo it is highly saline.
On the interior plateaus of the Andes and on the Gran Chaco plain there are many lakes of tectonic origin, shallow, drainless and saline. In addition, salt marshes and salt marshes (“salares”) are common.
There are large lagoon lakes along the low-lying shores of the Atlantic Ocean and the Caribbean Sea. The largest of these lagoons is located in the north, in a vast depression between the Andes ridges. It is called Maracaibo and is connected to the Gulf of Venezuela. The area of this lagoon is 16.3 thousand km 2, length -220 km. The water in the lagoon is almost fresh, but during high tides its salinity increases noticeably.
The lagoons, which have almost lost contact with the Atlantic Ocean, are located in the southeast of the continent. The largest of them are Patus and Lagoa Mirin .
A significant part of the continent, especially the Extra-Andean East, has large reserves of groundwater. In the sandy strata of syneclises not only in the Amazon, but also in the Guiana Lowland, Llanos Orinoco, Gran Chaco, Pampa, and also in other areas, up to 40-50% of the flow comes from groundwater.
Waterfalls
Waterfall Angel or Salto Angel- the world's tallest free-falling waterfall with a height of 978 meters.
Angel Falls is located in the Guyana Highlands, one of the five topographic regions of Venezuela, in South America. It is located on the Carrao River. The Carrao River is a tributary of the Caroni River, which eventually flows into the Orinoco. Getting to the waterfall is not easy as it is located in a dense tropical forest. There are no roads leading to the waterfall.
Angel Falls cascades from the top of a flat mountain called tepui by the natives. The flat mountain called Auyan Tepuy (Devil's Mountain) is one of more than a hundred similar ones scattered across the Guiana Highlands in southeastern Venezuela. These slumbering giants are characterized by their massive heights that soar into the sky, with flat tops and completely vertical sides. Tepuis, also called "table mountains" (which accurately describes their shape), were formed from sandstone billions of years ago. Their vertical slopes are continuously destroyed under the influence of heavy rains falling on the Guiana Highlands.
The natives of Venezuela have known about "Salto Angel" since time immemorial. The falls were originally discovered in 1910 by a Spanish explorer named Ernesto Sanchez La Cruz. However, it was not known to the world until its official discovery by American aviator and gold prospector James Crawford Angel, after whom it was named. Angel was born in Springfield, Missouri in 1899.
This enterprising experienced pilot in 1935 flew over the area and landed on the top of a lonely mountain in search of gold. His Flamingo monoplane was stuck in the swampy jungle at the top, and he noticed a rather impressive waterfall extending down thousands of feet. He had little luck on the 11-mile excursion back to civilization, and his plane remained chained to the mountain, a rusting monument to his discovery. Soon the whole world learned about the waterfall, which became known as Angel Falls, in honor of the pilot who discovered it.
Jimmy Angel's plane remained in the jungle for 33 years until it was recovered by helicopter. It is currently housed in the Aviation Museum in Maracay. The one you can now see on top of the tepui is its exact copy.
The official height of the waterfall was determined by an expedition of the National Geographic Society in 1949. The waterfall is the main attraction of Venezuela.
Waterfalls Iguazu- a wonder of the world, consisting of 275 different cascades of water, total area which are 2700 sq.m., and the fall height reaches 82 meters! The width of the waterfall is about 3 km. The largest waterfall is the Devil's Throat, a U-shaped cliff 150 meters wide and 700 meters long, marking the border between the countries of Argentina and Brazil. The name "Iguazu" comes from the Guarani words for "water" and "big".
Many islands separate the waterfalls from each other. Approximately 900 meters out of a total width of 3 km. not covered with water. About 2 km. The bridges connecting the islands help to better see all the streams. Most of the waterfalls are located within the territory of Argentina, but from the side of Brazil it opens good view on "The Devil's Throat".
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Smaller waterfalls are formed by ledges of durable rock, turning the water falling on them into clouds of fog and spray. sunlight adds the finishing touch to create shimmering rainbows. Below, in the middle of the water, an island covered with trees miraculously rose up. On one side of the island, where the water flows calmly, there is a beach with yellowish sand.
Different areas of the South American continent receive unequal amounts of precipitation, which explains the significant differences in the density of the continent's hydrographic network. The density of the river network, full flow and river regime depend on the characteristics of precipitation.
The Andes, stretching along the Pacific coast, blocking the flow to the east, also limits the drainage basin of the Pacific Ocean. It accounts for only 1/3 of the continent's drainage area. Numerous rivers of the Pacific coast are short, stormy, and rapids. Rivers in the northern and southern parts The Pacific basin is fed by heavy rains and meltwater from snow and glaciers. Occasional watercourses from the Andes barely make their way through the desert center, of which only the Rio Loa is able to carry its meager waters to the ocean. These rivers are fed mainly by groundwater, accumulating in sediments of crushed stone and sand.
The Atlantic Ocean collects runoff from the entire flat-mountain East and from the eastern part of the Andes, which usually receives a lot of moisture. The largest Andean river system, the Magdalena-Cauca in Colombia, also belongs to the Caribbean Sea. The well-moistened gentle slopes of the Guiana and Brazilian plateaus send their waters to the flat Amazonian lowland stretching between them with its constant downpours, where rivers also flow from the adjacent Andes ridges. It is not surprising that nature has created here the largest river basin in the world, with an area of over 7 million km2, with the deepest (and according to some sources, also the longest) river in the world, the Amazon. It originates near the Pacific coast, on the eastern slopes of the Western Cordillera in Peru, at an altitude of 4840 m. The Amazon has 2 sources: the more full-flowing Marañon (with it the river length is 6400 km) and the longer Ucayali (with it the river length is about 7100 km) . The river gets its name Amazon after the confluence of Marañon and Ucayali.
The Marañon flows north in a deep gorge and, turning east, breaks out into the lowlands, soon accepting its second source - the river. Ucayali. And then 4,300 km of free shipping route to the Atlantic with an insignificant drop. The Amazon is full of water all year round. The average water flow is 220 thousand m3/s, the maximum is up to 300 thousand m3/s. The Amazon regime depends on the timing of rainfall in the basins of its main tributaries, and 17 of them are 1500-3500 km long. The length of the shipping routes of the entire system is over 25 thousand km, the hydropower resources are enormous, approximately 280 million kW, but they are still extremely poorly used.
Favorable natural conditions formation of the second largest river in South America - the Paraná. It, with its mainly left tributaries, like Uruguay, which has a common mouth with it, flows from the southern slope of the Brazilian Plateau, replete with rapids and waterfalls. Her pool is well-watered. The main right tributary of the Paraná - Paraguay - is a lowland river, but with very sharp fluctuations in flow, and its tributaries from the Gran Chaco to winter time They may even dry out in places.
There are also very large fluctuations in the level of the third water artery - the river. The Orinoco flows at the junction of the Llanos and the Guiana Plateau. The left tributaries of the Orinoco are flat, and during the rainy season they overflow their banks; those on the right are distinguished by an abundance of waterfalls, sometimes cascading with the entire mass of water from the ledges of a crystalline bed, sometimes falling from steep sandstone walls, like the famous Angel. On the river Caroni in Venezuela has already built a cascade of hydroelectric power stations. A dense network of similar “waterfall” rivers also irrigates the eastern slopes of the Guiana Plateau.
Large areas in arid regions have no flow into the ocean at all. This is Puna, many areas of the Gran Chaco, the Pampinsky Sierras and, oddly enough, not only the dry western, but also the humid eastern Pampa, where precipitation is absorbed by porous loess or stagnates in flat depressions. Patagonia, whose rivers, originating in the Andes, cross it in deep canyons without receiving tributaries, do not have an external drainage and interfluve.
But the foothills of the Patagonian Andes abound in large lakes: Nahuel Huapi, Buenos Aires, etc. These terminal glacial lakes, dammed by moraines, with branched fjord-like bays cutting into the mountains, into which glaciers slide, surrounded by dense forests are surprisingly picturesque, and some of they are included in National parks. Similar lakes, only smaller in size, stretch in a chain on the other side of the Andes in Chile. There are many round tarn lakes in other glacial areas. The most remarkable lake in the Andes is Titicaca. It lies in Pune at an altitude of 3812 m and has an area of 8290 km 2 - 2 times higher and 3 times larger than Sevan. They are found in lakes and volcano craters in the Andes. There are few lakes in the east. The largest lagoon lake is Maracaibo, along the banks and from the bottom of which, as in the Caspian Sea, oil is extracted. The shallow large lagoon lakes Patus and Lagoa Mirin and a number of small ones are tied off by sand spits from the Atlantic Ocean on the coastal lowlands of Brazil and Uruguay.