National parks in the Cordillera. The meaning of the word cordillera. Allocate natural areas

One of the largest mountain systems on our planet is the Cordillera Mountains.

They amaze with their huge scale (they are perfectly visible from space, if you look at the mainland), length and extraordinary beauty with their inherent uniqueness of the local climate, flora and fauna.

Where are the Cordillera

The Cordilleras (Cordilleras English origin of the name) are located on west coast America and extend from north to south. These are huge mountains several thousand kilometers long, up to 18,000 km long and 1,600 km wide.

Looking at the physical map of the world, you can see that the mountains pass through 10 countries and capture the entire western hemisphere of the earth. The coordinates are impressive: south latitude 32/39/12; west longitude 70/00/42.

Note: the age of this system is simply enormous - the Cordilleras were formed in the Jurassic period, and scientists say that their formation has not yet ended, as evidenced by frequent volcanoes(more than 80 active).

The highest point of the Cordillera

The average height of the Cordillera is 3-4 thousand meters above sea level. The highest point of the Cordillera is Mount Aconcagua, located in South America in the Andes near the border with Chile.

Mount Aconcagua

And the place where the Andes formed is called the Patagonian platform. The absolute height of this mountain is about seven thousand kilometers (6961 m) above sea level.

In North America, the most high point The Cordillera is a Denali mountain located in southern Alaska. Mountain just below Aconcagua, height 6190 m.

Characteristics of the Cordillera of North America

The mountains originate in Alaska and pass through the entire continent, through three countries (Canada, USA, Mexico) to a point in the south in the valley of the Mexican river Balasas on the border with Central America.

The tectonic structure is complex, there are: areas of ancient, middle and new folding, many active volcanoes.

Throughout the length of the Cordillera there are three main belts:

• internal - consists of plateaus and plateaus in the middle of the western and eastern, there are many tectonic depressions with rivers;
• eastern - the belt of the Rocky Mountains, large ridges separate the Pacific Ocean and Gulf of Mexico with the Arctic Ocean;
• western - volcanic mountains parallel to the Pacific coast.

Three main arcs of the Cordillera

IN Central America mountains diverge into arcs:

1. One arc forms mountains in Cuba and northern Puerto Rico and Haiti. The arc was formed from the eastern and western belts, from the north.
2. The other starts from the borders of Mexico from the south, further through Central America, to the western part of Panama. This arc smoothly transitions into .
3. The last arc from the south of the western belt takes the direction to the mountains south side Puerto Rico and Haiti, and the mountains of Jamaica.

Geological structure and minerals

Lowlands between mountain ranges sedimentary rocks accumulated for a long time.

And now in the mountains North America large deposits of minerals were formed, while the mountains themselves are valuable in metal ore:

• there are oil fields in Alaska;
• the Rocky Mountains are rich in copper, gold, and tungsten;
• the coastal part of the ridges is of interest for the extraction of mercury and coal.

natural areas

Since the Cordilleras run through all of America, then natural areas mountains capture everything: forest-tundra, mixed forests, forest-steppes, forests, semi-deserts and deserts, tropical shrouds and forests. Only the arctic and subarctic zones are missing.

Rivers and lakes of the Cordillera

In the north of Alaska there are glaciers (large - Bering). Many rivers begin their journey in the Cordillera mountains, for example: Missouri, Yukon. Very full-flowing rivers of the Pacific basin.

The southern rivers are filled with rainwater, the northern rivers are fed by glaciers and snow.

Spring floods are typical for northern regions mountains The strong northern rivers are used for irrigation and power generation. Notable Reservoirs: Columbia, Colorado. There are also fresh and salt lakes.

Climate and climatic zones

The climate in the Cordillera is diverse due to the vast territory on which they are located:

1. Humidity in the southern part of the mountains is not more than 60%, and in the northern part up to 80%.
2. The average air t in summer in July is plus, in the south up to 30 degrees, and in the north up to 15. Winter average t in January in the north is -30, in southern regions -17.
3. The amount of precipitation per year is the largest in southern Alaska up to 4000 mm, and the most meager in the Mojave Desert - 50 mm.

Mountains, passing through all climatic zones:

• the south is the tropics and subtropics;
• the north of the belt changes climate from arctic to subarctic, then temperate;
• in the central, inland regions - the continental belt, and on the Pacific slopes of the mountains - the soft oceanic.

Flora and fauna

The natural landscape of the mountains is very diverse (due to altitudinal zonation).

Allocate natural areas:

1. Northwestern consists mainly of glacial mountain peaks and plateaus. The climate is harsh, permafrost, to the south coast - a little warmer. The landscape is tundra, woodland. Deer, lemings, and many birds live in the tundra. Bears, wolves, lynxes, cougars can be seen in the forests.
2. Canadian Cordillera in southeastern Alaska. Moderate climate, cedar and fir forests in the landscape. Tui grow on the slopes of the Pacific coast. The inhabitants of the forests are deer, mountain sheep, elks, bears, wolverines, cougars, foxes.
3. US Cordillera is the country where most of them are located. Nature is also very rich, on the slopes of the mountains - pine forests. There are dry plateaus. The low coastal mountains are covered with evergreen bushes and relict trees. The animal world is significantly exterminated. Lizards, snakes, rodents live in semi-deserts.
4. mexican cordillera- the climate is dry, there are many seismic zones. Shrubs, forests, cacti grow in the savannahs. Hares, wolves, cougars, rodents - residents local desert. Wolves, lynxes, bears live in the forests, and monkeys, tapirs, and predators live in the tropics.

National parks in the Cordillera

In order to see the many sights, you must definitely visit the reserves located on the territory of the Cordillera.

Grand Canyon

To get acquainted with the peculiarities of flora and fauna, appreciate the beauty of the landscape, see volcanoes, you can go to one of national parks:

1. In the USA - Grand Canyon, Yellowstone, Sequoia, Yosemite, Glacier.
2. In Canada - Yoho, Banff, Jasper, Garibaldi, Nahanni.

Conclusion

The area and grandeur of the Cordillera is amazing, geographical position And a large number of mountain ranges with amazing secrets beckons and makes you want to go on a trip.

Despite the fact that few people live in large areas, the vulnerable nature of the region has been damaged, which is difficult to restore.

Alaska has 13 national parks that protect typical natural complexes, and native species animals - mountain sheep, caribou deer, black bear (baribal) and grizzly.

Cordillera of Canada and Northwestern United States

This part of the Cordillera system is characterized by a relatively low mountain height and relative narrowness. It includes the Canadian Coast Range, the inland Fraser Plateau, the Columbian Plateau, and the Rocky Mountains up to about 48°N. sh. The westernmost orotectonic zone passes into the islands here. It is only in the south that the region expands, as this zone "returns" to the mainland. Its southern border runs along the northern outskirts of the Great Basin and the Sierra Nevada mountains.

Young folded ridges of the coastal zone are fragmented and lowered. The intermountain valleys are flooded with the sea and are straits and narrow long bays, deeply protruding into the land. The coast ridge continues the Nevadian zone, but its height is less than that of Alaska (2000-3000 meters, in the south - up to 4000 meters). It is dissected and processed by glaciers. The coast here is fjord-like.

Some general lowering of the mountains of the region in comparison with other parts of the Cordillera is presumably explained by the large area of ​​glaciation, both ancient and modern. It is possible that the earth's crust here, as it were, sags under the weight of ice. The inner plateaus are composed of lava covers reaching a thickness of up to 1200 meters. They are high (800-1500 meters), but narrow, expanding only to the south (Columbia Plateau - up to several hundred kilometers). Rivers, cutting through the plateau, form canyons. The Rocky Mountains consist of a series of longitudinal ridges up to 4000 meters high, separated by valleys and abruptly dropping to the east. A graben filled with glacial deposits stretches along the western slopes - the "Moat of the Rocky Mountains". It is believed that this is a continuation of the mid-ocean rift.

The amount of precipitation decreases from west to east (a common pattern for the Cordillera). The ocean coast receives 2000-3000 mm per year. Maximum - winter, snow cover in the mountains reaches an average thickness of up to 6-9 m. Summer is cool, cloudy. The climate is the same as on the coast of Alaska, only a little warmer.

Here, as on the coast of Alaska, "rain" grows. coniferous forests from Sitka spruce, Douglas, western hemlock, etc. with dense undergrowth, epiphytic mosses, ferns.

On the inner plateaus, features of continentality appear: there is little precipitation (300-400 mm), temperature amplitudes increase. In the north there are areas of taiga on podzolic soils, which are replaced by forest-steppe and steppe to the south. Wormwoods appear in the extreme south. The slopes of the Rocky Mountains are covered with pine forests and shrubs, while the valleys are treeless.

The Cordillera of Canada has a large number of mountain glaciers of various types.

The region is rich in minerals, both ore (copper, iron, lead, zinc, silver, gold) and non-metallic, such as coal. Forest resources and the hydro potential of rivers are used. Tourism is developed, especially in the mountains British Columbia. A number of national parks have been created for nature protection - Jasper, Banff, Glacier, etc.

Cordillera of the Southwestern United States

The physiographic country is located approximately between 48 ° and 32 ° N. sh. in the widest and most diverse natural conditions parts of the Cordillera mountain system. The region experienced a general uplift in the Paleogene-Neogene, which was accompanied by faults, denudation, and large erosional dissection.

Here, the manifestations of faults are most clearly visible at the junction of the continental (North American) and oceanic (Pacific) crust. Quite clearly visible are the zones of deep subsidence of the oceanic crust under the continental crust in the California region, where there is a huge gap in the coastal areas. The San Andreas Fault extends in a northwesterly direction for almost 900 km. It has existed since the pre-Mello time, and is still very active today.

Three structural and morphological zones are clearly traced: axial, the most ancient - Nevadian, in the east - Laramian, in the west - young Cenozoic Coast Ranges, the development of which continues to the present.

Modern climatic conditions are characterized by high contrast, which is associated with the position in two climatic zones(temperate and subtropical), significant amplitudes of heights, the presence of mountain barriers in the path of sea air masses.

Areas with annual precipitation up to 100 mm and maximum temperatures up to + 57 ° С (Death Valley) are adjacent to the mountains, where the annual precipitation is up to 2000 mm and even in summer negative temperatures prevail (upper sections of the Sierra Nevada). In the west it has a Mediterranean type climate. In other parts of the region, climatic conditions features of continentality appear.

Different parts of the region differ significantly in all components of nature.

The eastern (Laramian) structures of the Rocky Mountains are often referred to as the continental divide, with elevations of 1,800 m and above.

The ridges are anticlinal folds that have Precambrian cores. Some of them are elongated in the general direction of the entire mountain system from northwest to southeast (the Front Range, Sangre de Cristo, etc.), but there are ranges of a different orientation, sometimes even sublatitudinal. Between them formed vast plateau-like areas connecting the Great Plains with the Great Basin - the so-called "parks". They are composed of sedimentary strata of Paleozoic-Mesozoic age. The summit areas were covered by the Wisconsin glaciation, preserved troughs and kars. Spruce-fir and pine forests are widespread on the slopes of the mountains, the bottoms of the "parks" are usually treeless. In the south and along the slopes of the mountains, steppes and semi-deserts rise.

In the northeast is the Yellowstone Plateau (“yellowstone” in English means “yellow stone”) with a Paleogene cover and young lava covers, having a thickness of more than 1000 meters.

It is known as one of the largest areas of the Earth with geysers and thermal springs. Under powerful lava covers (300-600 meters) forests of ancient sequoias are buried. Their petrified trunks are often found (there is a section with 12 layers of petrified forest covered with volcanic ash). In 1872, the Yellowstone National Park was founded here (an area of ​​about 900 thousand hectares, located at an altitude of 2100 m to 3400 m). There are 200 water thermal and mud springs, about 300 geysers on the territory of the park. The greatest geyser Exilor with a griffon diameter of 8-10 meters "works" here, which throws water up to 100 meters up. The mineral sediment forms geyserite of various shades - blue, purple, pink, etc. The wildlife of the park is rich - bison (their number has increased 20 times since the beginning of the century and amounts to several hundred heads), a variety of brown bear - grizzly, coyote, fox, skunk, badger, puma and 150 species of permanent birds. Access to the park is regulated. The park is divided into zones, each of which solves certain problems: there is a zone of strict protection, where no human influence is allowed, a zone of “managed” protection (to preserve natural landscapes), a zone organized tourism and a tourist-administrative zone (camping sites, parking lots, cafes, office buildings).

In the inner part of the physiographic country, west of the Rocky Mountains, there is the largest inland highlands - Big Pool and the Colorado Plateau.

The Great Basin has undergone a complex history of formation: Paleozoic and Mesozoic folding, Mesozoic sedimentation, and intense deformation of structures.

The modern relief was formed in the Cenozoic under the influence of submeridional faults along the rift between the Rocky Mountains and the Sierra Nevada mountain range. Clastic material filled intermountain depressions. Active volcanism appeared in the northwest. At present, the rejuvenated relief with numerous internal drainless depressions has a wide variation in absolute heights - from 1500-2000 meters to -85 meters (Death Valley). This is the result of powerful vertical movements.

Due to the barrier role of the Cascade Mountains and the Sierra Nevada, which prevent the transfer of Pacific air masses, a climate with well-defined features of continentality has developed.

The annual amount of precipitation here does not exceed 90-100 mm. The result of the dry climate is the weak development of the river network, which has no flow into the ocean. There is no removal of destruction products outside the basin, so the clastic material buries and levels the mountainous terrain.

Within the highlands, a hundred relict lakes - Big Salt (the rest of Lake Bonneville, most of which the river was lowered. Snake).

The soil and vegetation cover and fauna are typical for deserts and semi-deserts of the temperate and subtropical zones. The Americas have a different appearance than the deserts of Eurasia.

Along with saline and rocky deserts, there are areas with a pronounced seasonality, when ephemera bloom brightly in spring. In the southern part of the basin, a “woodland” of cacti (up to 10 meters high) and yucca has formed. Pine and juniper with steppe grasses grow on the slopes of the ridges. Picturesque Sonoran Desert in Arizona. The hilly plain is composed of sedimentary rocks and has insular volcanic mountains. The desert is inhabited by many species of cactus, including the giant tree squaw. volcanic mountains, overgrown with this plant, seem from afar covered with a sparse forest, devoid of small branches and leaves. The age of cacti is tens and hundreds of years, height 10-12 meters, trunk thickness up to 70 cm, coyotes and many poisonous snakes live under them. In addition to cacti, other xerophytic plants grow in Sonora, which can tolerate not only drought, but also extremely high air and soil temperatures. The fauna of the desert is diverse and interesting.

The Colorado Plateau is an area of ​​horizontal occurrence of Phanerozoic rocks of different lithological composition. A highly elevated structural plain (more than 3,500 meters in places) is framed by cuestas.

The deeply incised river network has created steep-sided canyons that expose all the different colored rocks that make up the plateau. On the outskirts of the plateau, volcanic rocks are widely represented in the form of intrusions and laccoliths. The main watercourse - r. Colorado, which cut through the plateau, creating the Grand Canyon. The main canyon has a winding shape, its depth is 1800 m, maximum width up to 25 km, length over 300 km.

To the west of the internal plateaus are Nevadian structures - the Sierra Nevada mountains. This is a large block structure (horst boulder with comb-like peaks), the blocks are inclined to the west, there are batholiths at the base. Cascade Mountains - a prime example volcanic ridge with a number of active volcanoes. The folded structures within them are covered by Cenozoic lavas, and high (some higher than 4000 m) volcanic cones are planted on them. Among them there are also very active: in the 80s. 20th century Mount St. Helens erupted two years in a row, there were many deaths. There are also extinct, but showing post-volcanic activity.

The vegetation of the mountains is typically American.

Here in the valley Merset (Yosemite Valley) preserved forest (park) of the giant sequoiadendron. For their large size (the height of many trees reaches 80-100 meters) and for bending, like mammoth tusks, their branches were called mammoth trees. In the lower tier of the mountains - chaparral (American variety of maquis).

Coastal ridges - low (up to 2400 meters) Pacific structures are separated from the Nevadian structures by the Willamette and California valleys. This is the result of subduction from latest education shifts and faults, such as, for example, San Andreas.

This fault is especially active. The blocks of the earth's crust move horizontally relative to each other at high speed. The process is accompanied by strong earthquakes. So, for example, in 1992, an earthquake occurred 150 km from Los Angeles in the Mojave Desert, during which more than 5,000 shocks of various strengths were recorded in 10 days. Suffer from earth tremors big cities- San Francisco was badly damaged in 1906, in Los Angeles there were shocks of 7-8 points in 1971.

The climate is subtropical with humid warm winter(up to 10°C) and dry summers. On the coast, summers are cool (average July temperatures are about 15°C), due to the influence of air masses with a northern component and cold currents. When moving inland, summer becomes much warmer (20-22°C). The annual amount of precipitation is 500-600 mm with a winter maximum. The lower tier of mountains is occupied by an analogue of the Mediterranean maquis - chaparral (thickets of shrubby oak, deciduous and evergreen, 1.5-2 meters high, less often - 3 meters, on brown, above 600 meters - stony soils). In the south - thickets of acacia, cacti, yucca. The upper tiers are dominated by coniferous forests of Sitka spruce, Douglasia, pines, sequoias.

On the northern parts of the western slopes are National parks, where forests of evergreen sequoia (mahogany) are taken under protection. national park Redwood is located north of San Francisco, in the valley of the river. Redwood Creek. Sequoias are the tallest and oldest trees, along with mammoth trees from the same family. Sequoia grows up to 2000 years. The phytomass of the thousand-year-old sequoia is more than 4,000 thousand c/ha (1% is needles, the rest is the trunk and branches), the yield of commercial wood is 10 thousand m 3 /ha. Trees are not afraid of fires.

Of all the regions of North America, the Cordillera of the southwestern United States stands out for its variety of natural attractions that attract tourists from all over the world.

In addition to recreational, this region has good agro-climatic and land resources. In the Great California Valley, the natural vegetation of dry wormwood steppes and semi-deserts has been completely replaced by cultivated vegetation. On lands irrigated by the waters of rivers flowing down from the mountains, a variety of subtropical crops are grown. On the coast Pacific Ocean giant urban agglomerations were formed, connected by high-speed highways. From Richmond, Oakland, San Francisco to Los Angeles, including the famous Hollywood, continuous urban development stretches.

The most acute problem is pollution: all harmful emissions remain near the surface of the earth, since a significant part of the year is dominated by the anticyclonic regime and descending air currents. Frequent fogs.

Cordillera, the greatest in length mountain system of the globe, stretching along the western outskirts of North and South America, from 66 ° N.S. (Alaska) to 56°S sh. (Tierra del Fuego).

The length is more than 18 thousand km, the width is up to 1600 km in North America and up to 900 km in South America. Located in [Canada, USA, Mexico, Central America, Venezuela, Colombia, Ecuador, Peru, Bolivia, Argentina and Chile.

Almost along its entire length, it is a watershed between the basins of the Atlantic and Pacific oceans, as well as a pronounced climatic boundary. In height they are second only to the Himalayas and mountain systems Central Asia. The highest peaks of the Cordillera: in North America - Mount McKinley (6193 m), in South America - Mount Aconcagua (6960 m).

The entire Cordillera system is divided into 2 parts - Cordillera of North America, and the Cordillera of South America, or the Andes.

The main mountain-building processes that resulted in the emergence of the Cordillera began in North America in the Jurassic, in South America at the end of the Cretaceous and took place in close connection with the formation of mountain systems on other continents (Alpine folding). The formation of the Cordillera has not yet ended, as evidenced by frequent earthquakes and intense volcanism (more than 80 active volcanoes). An important role in the formation of the relief of the Cordillera was also played by the Quaternary glaciation, especially north of 44° N. latitude. and south of 40°S.

The Cordilleras lie in all geographic zones (except for the subantarctic and antarctic) and are distinguished by a wide variety of landscapes and a pronounced altitudinal zonality. The snow limit in Alaska is at an altitude of 600 m, in Tierra del Fuego - 500-700 m in Bolivia and South Peru rises to 6000-6500 m. In the northwestern part of the Cordilleras of North America and in the southeast of the Andes, glaciers descend to ocean level in the hot zone they cover only the highest peaks. total area glaciations - about 90 thousand km 2 (in the Cordillera of North America - 67 thousand km 2, in the Andes - about 20 tons km 2).

Literature

• Geographic encyclopedic dictionary, M., 1986.

Cordillera - mountains, a huge system of which occupies western edge continent of North America. They stretched for about 7 thousand km. The Cordilleras are mountains characterized by a wide variety of natural conditions. They are characterized by a number of features, and this determines their uniqueness among the rest of the mountain systems of our planet.

General characteristics of the Cordillera

Where are the Cordillera Mountains located? They are predominantly elongated in the submeridional direction. These mountains are formed within five orotectonic belts of different ages. The Cordilleras have in their composition a significant proportion of highlands (2.5-3 thousand or more meters above sea level). They have active volcanism and high seismicity. The large extent of these mountains from north to south has led to the presence here of many spectra of altitudinal zonality. Cordilleras are mountains formed at the junction between lithospheric plates. The border between them almost coincides with the coastline.

Composition of the Cordillera

The third part of the area of ​​the entire continent is occupied by a mountain fold-block system. It has a width of 800-1600 km. It includes mountain plateaus, intermountain basins, ranges, as well as volcanic plateaus and mountains. Young deformations, volcanism, denudations have undergone the Cordillera, which determined their current appearance and disguised many geological structures that appeared earlier. The mountain system is very heterogeneous both in the transverse and in the longitudinal direction.

More about the structure of the Cordillera

The structure of the surface of the mainland, where the mountains of the Cordillera are located, is asymmetrical. They occupy the western part of it, the eastern - low mountains and vast plains. West Side located at an altitude of about 1700 meters, and the eastern one - 200-300 m. 720 meters is average height continent.

The Cordilleras are mountains that include a number of mountain arcs, which are elongated mainly in the direction from the northwest to the southeast. From Mackenzie, Mt. Brooks, the Rocky Mountains consists of the eastern arc. A discontinuous belt formed from internal plateaus and plateaus is located to the west of these ranges. 1-2 thousand meters is their height. The Cordilleras are mountains that include the following plateaus and plateaus: the Yukon Plateau, the Columbian Plateau and the British Columbia Plateau, the Great Basin, the plateaus and the volcanic plateau of the Mexican Highlands (its inner part). For the most part, they represent an alternation of basins, ridges and table flat surfaces.

The highest mountain

The Cordilleras from the western part are marked by a system of the highest ridges. These are the Aleutian Ridge, the Aleutian Islands, the Alaska Ridge. The latter reaches a height of 6193 meters. This is McKinley, the highest mountain shown in the photo above. The Cordillera is a system that also includes in the western part the Cascade Mountains, the Canadian Coast Range, the Western Sierra Madre and the Sierra Nevada, as well as the Transverse Volcanic Sierra located here (5700 meters), etc.

To the west of them, the height decreases. The Cordilleras are mountains that smoothly merge into the flat part of the mainland. It is occupied in the west by either Puget Sound, Cook), or lowlands (California Valley, Willamette River Valley). This coast of the continent is formed by the St. Elijah, Chugach, Kenai, Canadian Island Ranges, and the US Coast Ranges. The chains of the Cordillera to the south of the Mexican highlands bifurcate. One of them deviates to the east, forming the islands of the West Indies and underwater ridges, after which it passes into the Venezuelan Andes. The second half stretches through the Isthmus of Panama and Tehuantepec to the Colombian Andes.

What is the reason for the diversity of the relief of mountains?

It is associated with different ages of land areas, as well as with the history of their development. The mainland did not immediately form in its present form. The mountains of the Cordillera in their present form arose thanks to various processes that took place in different time on the continent.

For the Laurentian Upland, marked by the most ancient geological structures, the relief is characterized by leveling surfaces, the formation of which began at the beginning of the Paleozoic. The wavy surface of the modern upland was determined by the different resistance of rocks to denudation, as well as uneven tectonic movement. The lowering of the central part of the territory caused a cover Quaternary glaciation, due to which the depressions of the modern one were formed. In addition, under its influence, the accumulation of water-glacial and moraine sediments occurred, which formed the type of relief (moraine-hilly).

Great and belong to the type of reservoir. Under the influence of denudation processes in different places, depending on the characteristics of the occurrence of various rocks, cuest ridges (Great Lakes), stepped plateaus (Great Plains region), midlands and erosion low mountains (Washita, Ozarks) were formed.

The relief of the Cordilleras themselves is very complex. The strip of compression of the earth's crust is crossed by numerous faults, starting from the bottom of the ocean and ending on land. The mountain building process has not been completed yet. This is evidenced by volcanic eruptions (for example, Popocatepetl and Orizaba), as well as strong earthquakes that occur here from time to time.

Minerals

As you know, many different minerals can be found where there are mountains. The Cordillera is no exception. There are huge reserves of ores of non-ferrous and ferrous metals. From non-metallic, one can distinguish oil, which is located in intermountain troughs. Stocks of brown coal are available in the Rocky Mountains (their internal basins).

Climate

We continue the description of the mountains with the characteristics of the climate. The Cordilleras are in the path of oceanic air masses. Because of this, in eastbound the influence of the ocean is drastically weakened. This climatic feature The Cordillera is reflected in the soil and vegetation cover, the development of modern glaciation, and altitudinal zonation. The elongation from north to south of the mountain ranges predetermines the differences in temperatures in summer and winter. In winter, it ranges from -24 ° С (in the Alaska region) to +24 ° С (Mexico, south of the country). In summer the temperature reaches from +4 to +20 °С.

Precipitation

The northwest receives the most rainfall. The fact is that this part of the Cordillera is located on the path of the westerly winds blowing from the Pacific Ocean. The amount of precipitation here is approximately 3000 mm. Tropical latitudes are the least humidified, since oceanic air masses do not reach them. The low amount of precipitation is also due to the cold current passing near the coast. The inner plateaus of the Cordillera are also not very wet. The mountains are located within the temperate, subarctic, tropical and subtropical climatic zones.

Rivers and lakes of the Cordillera

A significant part of the western rivers of the continent originates precisely in the Cordillera. Mostly their food is snow and glacial, in the summer there is a flood. These rivers are mountainous, swift. The largest of them are Colorado and Columbia. The lakes of the Cordillera are of glacial or volcanic origin. On the inner plateaus there are saline shallow water bodies. These are the remains of large lakes that existed here for a long time, in times of a humid climate.

Vegetable world

The flora of the Cordilleras is very diverse. Coniferous forests with a peculiar appearance are located up to 40 ° N. sh. In terms of species composition, they are very rich. Spruce, cypress, fir, thuja (red cedar) are their typical representatives. The height of coniferous trees reaches 80 meters. Between them there is practically no woody undergrowth. However, a variety of shrubs grow here in abundance. There are many mosses and ferns in the ground cover. In the coniferous forests, when moving south, sugar pine, white fir, and yellow pine begin to come across. The evergreen sequoia appears further south. As dryness increases, south of 42 ° N. sh., thickets of bushes are replaced by forests. They are juniper, heather, and their height usually does not exceed two meters. Here you can sometimes find different types evergreen oak. The humidity of the climate in the interior of the Cordillera is decreasing. They are characterized by dry forests, as well as areas of saltwort and wormwood deserts. The mountain slopes that receive rainfall are covered up to a height of 1200 m with evergreen forests.

Animals living in the mountains of the Cordillera

Where the mountains of the Cordillera are located, you can meet the brown grizzly bear - a large predator of the continent of North America. having long black fur, lives in the southwest of this system. It destroys livestock and spoils crops. There are also many lynxes, foxes, wolves. Arthropods, lizards, snakes are often found in the southern regions of the mountains. In addition, the gilatooth lives here - the only legless poisonous lizard. Large animals in places where people live are either destroyed or are extremely rare. Bison and pronghorn (a rare antelope) are only saved through national programs in North America. Only in the reserves one can observe today a rich animal world.

Southern shores of Tierra del Fuego (56° lat.). The length is more than 18 thousand km. Located on the territory of Canada, USA, Mexico, Central America, Venezuela, Colombia, Ecuador, Peru, Bolivia, Argentina, Chile. Forms a high barrier between the plains eastern parts continents and the Pacific coast. Almost throughout its length. are a watershed between the Atlantic and Pacific oceans, as well as a pronounced climatic boundary between countries lying on both sides of the mountain uplift. Kabul is second only to the Himalayas and the mountain systems of Central Asia in height. The highest peaks of K.: in North America -. McKinley (in Alaska), 6193, in South America - the city of Aconcagua, 6960 m. The entire K. system is divided into 2 parts - the Cordillera of North America and the Cordillera of South America, or Andes, and consists of numerous parallel ridges, bordering the intermittent belt of internal plateaus and plateaus (in North America - Yukon, Fraser, Colombian, Basin, Colorado, Mexican; in South - Peruvian and Central Andean). In North America, 3 parallel systems of mountain ranges are expressed, of which one passes to. from the zone of plateaus (Rocky Mountains), another - directly to the west from this zone (Alaska Range, Coastal Range of Canada, Cascade Mountains, Sierra Nevada, etc.) and the third - along the coast of the Pacific Ocean, partially - on offshore islands. In Central America, K. go down and bifurcate. One of their branches goes along Antilles, the other through the Isthmus of Panama passes into the territory of South America. The Andes in the northern and central parts consist of four, and in the rest of the length of two systems of parallel ridges, separated by deep longitudinal depressions or intermountain plateaus. The highest are the ridges of the middle part of the Andes, where the height of individual peaks reaches more than 6700 m (Aconcagua, 6960 m; Ojos del Salado, 6880 m; Sajama, 6780 m; Lullaillaco, 6723 m). The width of the mountain belt in North America reaches 1600 km, in South - 900 km. The main mountain-building processes that resulted in rock formations began in North America in the Jurassic, and in South America (where the structures of the Paleozoic Hercynian folding play a large part) at the end of the Cretaceous and took place in close connection with the formation of mountain systems on other continents. Alpine folding). Mountain-building movements actively continued in the Cenozoic. These movements largely determine the main orographic elements. The folded structures of Kazakhstan are closely connected with the mountain systems of the north-east. Asia and Antarctica. The formation of K. has not yet ended, as evidenced by frequent earthquakes and intense volcanism. There are more than 80 active volcanoes here, of which the most active are Katmai, Lassen Peak, Colima, Antisana, Sangay, San Pedro, and the volcanoes of Chile. ° c. . and to the south from 40 ° south. sh. Within China there are significant deposits of copper, zinc, lead, molybdenum, tungsten, gold, silver, platinum, tin, oil, and others. K. This mountain system lies in all geographical zones (except for the Antarctic and Subantarctic). The climate of K. varies greatly depending on the latitude of the area, the height, and the exposure of the slopes. The marginal ranges are abundantly moistened in the temperate and subarctic zones ( western slopes) and in the equatorial and subequatorial belts (mainly eastern slopes). The internal plateaus have a sharply continental climate; in the subtropical and tropical zones they are distinguished by exceptional aridity. Significant parts of the plateaus, internal depressions and slopes of the ridges, mainly in the tropical zones, are occupied by steppes, semi-deserts and deserts. The heavily moistened outlying mountain chains are covered with dense forests. Coniferous forests (in the north) and mixed forests of evergreen beeches and conifers (in the south) are widely developed in the temperate zones; closer to the equator, mixed (deciduous-evergreen) subtropical and rainforests. On the wet slopes of the ridges of the equatorial, subequatorial and subtropical belts, there are complex spectra of high belts, from hyla to eternal snow. The snow limit lies in Alaska at an altitude of 600 m, in Tierra del Fuego 500-700 m, in Bolivia and Southern Peru it rises to 6000-6500 m. In Alaska and Southern Chile, glaciers descend to ocean level, in the hot zone they cover only the highest tops. G. M. Ignatiev.