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Geography of North America Nature

Land

Along the west side of North America lies the Cordillarians, a complex of several parallel mountain ranges, averaging 4,000–5,000 m high. Of the peaks, Mount McKinley in Alaska (6,194 m asl) is highest. The chains are separated by valleys, such as the Central Valley in California, or by plateaus, often with desert conditions, such as the Great Basin, the Colorado Plateau and the Mexican highlands. Volcanoes are common in the western part of the Cordillaries, from the Aleutian archipelago in the north to Panama in the south. Many volcanoes are active. Earthquakes often occur in the Cordillarians, especially in the western part. Glaciers and glacial erosion forms the highest parts of the mountains. Along the south coast of Alaska, glaciers reach as far as the sea. There and along Canada's west coast there are fjord coasts and large archipelagos.

To the east of the Cordillarians is the northernmost Canadian shield. It is a heavily degraded urban area characterized by glacial erosion and therefore has a large number of lakes. The lowest portions of the shield form Hudson Bay; the highest parts of northeastern Labrador reach about 1,600 m above sea level. The shield continues north in the Arctic archipelago.

To the south, south and west of the Great Lakes, the central lowland, 200–500 m above sea level, spreads. It continues to the west in the Great Plains, plains that gradually rise from about 500 to close to 2,000 meters above sea level. at the Rocky Mountains, the easternmost of the Cordillarians' chains. To the south, the lowlands turn into a coastal plain. The entire area south of the Shield is drained by the Mississippi River with tributaries.

To the east, the lowlands are bordered by the Appalachians, with elevation ranges up to 1,500 m above sea level. The highest point, Mount Mitchell in the south, reaches 2,037 m above sea level. East of the Appalachians, from New York to Florida and along the Gulf of Mexico to the Yucatán, the coastal plain is spreading. It continues in the lowlands of Cuba, which is the only major plain in the mountainous Great Antilles. The Little Antilles consist of high volcanic islands and low coral and sand islands.

Soil and soils

North America has been built around the Canadian shield, which forms the bedrock in northern and eastern Canada, in the northeastern United States and in most of Greenland. This rock shield consists of rocks formed during the Precambrian (older than about 570 million years), mainly granites and gneisses. The latter have mainly been formed through the transformation of sedimentary and volcanic rocks. The shield began to form through volcanic activity and rock formation (orogenesis) more than 3 900 million years ago. This first orogenesis was followed during the pre-Cambrian by at least five more orogenesis, which meant that new crustaceans were gradually added to the continent. The mountain ranges (orogens) that build up the Canadian shield are today completely degraded.

In the south and west, the shield is covered by flat-lying sedimentary rocks formed from Cambrian to Tertiary (about 570–1.65 million years old). These rocks build up the North American platform, which together with the Canadian shield forms a craton, ie. a stable continent that has not been exposed to mountain range formation or extensive deformation since Proterozoic (more than 570 million years ago). The craton is surrounded by mountain ranges from the phanerozoic (younger than about 570 million years).

During the older Paleozoic period (about 510–409 million years ago), the North American craton (Laurentia) moved on a collision course towards Europe. The collision resulted in the Caledonian orogenesis, a mountain range formation that one can trace in North America from the northern Appalachians via Newfoundland to Greenland's east coast. A Caledonian mountain range zone also extends along Greenland's north coast towards Arctic Canada. During the Varian orogenesis in the younger Paleozoic (approximately 375-245 million years ago), the majority of the Appalachians were formed through a collision with northwestern Africa.

Large parts of the mining area formed under the Precambrian were covered under Cambrian to older carbon (about 570–323 million years before today) by warm groundwater, where sandstones, clay shales and limestones were formed. In younger carbon (about 323–290 million years before today), the conditions were alternately marine and continental. Swamp forests had a widespread distribution, resulting in coal-bearing stocks, especially in the central lowlands and west of the Appalachians. During Perm and Triassic (approximately 290–208 million years before today), North America had a warm and dry climate.

Mainland conditions dominated and continental sediments, e.g. red-colored sandstones, deposited. With the exception of parts of the western United States and southwestern Canada, there were also prevailing legal conditions (approximately 208–146 million years before today) mainly in mainland conditions with the provision of continental stock sequences. Some of these stock sequences, in particular the Morrison Formation in the western United States, are known for their rich occurrences of dinosaurs. During Cretaceous (about 146-65 million years before today), the sea again covered large areas, and thick stockpiles were deposited east of the Cordillarians.

Until the beginning of the tertiary (about 60 million years ago), North America was still associated with Europe. The North Atlantic then expanded further and North America continued to move westward, a movement that is still ongoing at a rate of about 1 cm per year. Through North America's movement westward, a collision with the seabed to the west occurred. From the folded material, a new continental crust was created in the form of the Kordiljärna mountain range along the west side of the continent. This complex of parallel mountain ranges was formed during the alpine orogenesis. Mountain range formation in the area has been going on at least since the end of the Devon (about 370 million years ago), but the true Cordillarians only started to form at the beginning of the tertiary. The mountain range complexes in the west have given rise to large amounts of sediment deposited east of the Cordillaries.

During the early part of the tertiary, up to the middle of the Eocene (about 45 million years ago), North America had land links with Eurasia, and the fauna of the continents was similar. Subsequently, the continents were separated and with the exception of short periods, North America was isolated until the latter part of the Miocene (about 15-10 million years ago). This led to the development of an endemic flora and fauna, which came to mix with the Eurasian at the end of the Miocene epoch.

The quaternary period (the last 1.65 million years) is characterized by repeated cold times. In North America, traces of four major icings have been found. During the maximum extent, the inland ice covered all of Canada and Greenland, the northern parts of the Mississippi Basin and the northeastern United States. Local rock carvings occurred on the mountain ranges in the western United States. The North American fauna has been heavily influenced by immigration waves from Asia over the Quaternary period via the land bridge that was sometimes established over the Bering Strait. The emergence of the Panamanese in the late Tertiary (about 3.5 million years ago) has also been of significance for the fauna's composition and changes in it.

In northern North America, the soils are moraine and other glacial deposits. Loose soils have a widespread distribution in the central United States, especially in the central lowlands. Other loose deposits can be found, for example, on the coastal plains to the east of the Appalachians, along the Gulf of Mexico and in sinks in the Cordillarians. In other areas, there are mainly weathering soils.

Soils

The northern part of the Arctic climate is covered by leptosols with thin soil cover or cryosols with permanent scab (permafrost). In the temperate zone south of it, pod soles predominate on sandy soils and albelu visols and cambisols (brown soils) on more fine-grained soils. In more humid climatic conditions in this zone, there are organogenic and other water-affected soils (histosols and slides). In the hot and humid area of the southeastern United States, there is an area of heavily weathered soils (acrisols and alisoles).

The prairie in the interior of the continent is dominated by humus-rich steppe moons (chernozems and castanozems) surrounded by deciduous forests with clay enrichment horizons (luvisols). In the desert areas of the southwestern United States and northern Mexico, calcisols are the natural soil. In Texas, there is an area with clay-rich vertical insoles.

In the tropical climate of Central America and the Caribbean, highly weathered soils (nitisols, acrisols and alisols) take over. Volcanic soils (andosoles) are also common in this area.

Climate

As a result of the great extent of the North American continent in the north-south direction, there are a number of different types of climate. In the far north, the climate is cold, in the middle temperate and in the Caribbean and on the Central American nose tropical. When mountain ranges or other topographic barriers in the east – west direction are missing, the entire continent becomes funnel-open from north to south. This facilitates the exchange of air masses of different character, and the weather development can be very dramatic. Thus, cold air masses can penetrate far south and cause frost and snow, while on the other hand warm and humid air masses can affect the climate all the way up in southern Canada. Tropical cyclones often develop in the border zone between hot and cold air, which can cause major damage, especially in the southeastern United States.

A topographical feature of the continent's structure that has a significant impact on the climatic conditions in the western parts is the Cordillarians. Because the air currents from the Pacific are forced upwards as they reach the high and long mountains precipitates abundantly with precipitation on the west side of the mountains, while rain shadow and dry climates arise further east. From Oregon in the northwestern United States to Alaska, the west wind impacts and causes rainfall to exceed 2,000 mm per year in a narrow belt along the coast. The California current (a cold ocean current outside of California) and outward winds mean that the rainfall here is very low. Within this western area also arise storms which are then driven by a jet stream and converge towards New England.

Cold climates have a very wide distribution in North America. This is largely due to the continent's location and shape - the continent has its greatest breadth at high latitudes and tapers to the south. The northernmost parts, including the Canadian Shield and Archipelago and Greenland, have polar climates. The average temperature here is around –18 °C for five to seven months of the year. Only during June to September is the temperature above 0 °C. The majority of the area has constantly frozen ground, permafrost, with tundra and polar desert. South of this, an extensive area of cold-temperate, humid climate takes over. It extends from Alaska to Newfoundland, from Hudson Bay to the Ohio River. The winter is cold and long and the temperature from October to April is below 0 °C. Freezing periods in spring and autumn can destroy the crops, while tropical air masses from the south quickly raise the June temperature to above 10 °C. The rainfall stays between 275 mm and 875 mm, which is sufficient because it falls during the growing season and the evaporation is small.

Warm temperate, humid climate is found in the southeastern part of North America. The area is strongly influenced by tropical air masses from the Gulf of Mexico. Winter becomes mild with January averages of 4 to 12 °C. July has an average of 28 °C. The annual rainfall amounts to between 1,000 and 1,500 mm. The tropical air masses, especially in the summer, can give rise to devastating cyclones that pull all the way up the Mississippi valley. In southern and central California, there is a Mediterranean climate with winter rainfall and mild and dry summer (21-27 °C).

Tropical climates with abundant rainfall (rain forest climate ) are prevalent mainly in Central America, apart from the higher levels that have mountain climates. Winter is missing and the summer temperature is around 27-28 °C. The rainfall is between 1,125 mm and 2,000 mm per year and is introduced by the eastern pass winds. The coastal areas are often hit by tropical cyclones during the summer, which can cause great damage.

Dry climates occur in both cold and warm parts of North America. If the polar regions are included, the dry climate areas occupy one third of the continent's surface. Main areas for arid and semi-arid climates with desert and steppe are found in the southwest. They are caused by the high-pressure belts of the middle widths with stable, descending air or by the rain shadow effect found east of Sierra Nevada. The air moving down from the high, inner plateaus also gets drier. The drought in the Arctic is due to the fact that most water collections are frozen for six to nine months and that cold air can hold only a small amount of humidity.

Plant Life

South of the tundra in North America, the boreal coniferous forest zone takes over. Black spruce, white spruce, fir branches and larch go farthest to the north, and large areas are covered with marshes and mosses. Along the west coast from southern Alaska to California are moist, rich coniferous forests. American sequoia in Northern California is the world's tallest tree, while the mammal tree in Sierra Nevada has the largest pulp.

In California, the vegetation type is chaparral, dominated by evergreen shrubs and small trees, including oaks, pines, mills, conifers (Arbutus) and sack bushes (Ceanothus). The area is rich and has many endemic species. The arid regions of the southwestern United States and northwestern Mexico are dominated by cactus plants, such as saguaro (Carnegiea gigantea), as well as palm lilies and agave. A characteristic species is creosote bush (Larrea tridentata).

The forests in the Klippiga mountains consist of, among other things, yellow numbers, contort numbers, blue-spruce and angelic branches ; at high altitude also grows American aspen (Populus tremuloides). Important herb genera in western North America are Native American brushes (Castilleja), flocks, woolen slippers as well as many wicker plants and pea plants.

The Atlantic region encompasses the area east of the Rocky Mountains. The boreal coniferous forest forms a continuous belt there. The tree line extends farther south in the eastern parts, in Labrador at about 53 ° 30 'north latitude. Around the Great Lakes and in New England, mixed forests with conifers such as weymouth pine, white spruce, balsam fir and hemlock dominate. Among the deciduous trees, sugar maple and species of birch, elm, oak and linden dominate. The area is relatively similar to Northern Europe; some species, especially in marshes and mosses, are found on both sides of the Atlantic.

In the eastern and central United States there are rich summer green deciduous forests. In addition to the genus that is also found in Europe (oaks, ashes, walnuts and chestnuts ), there are also hickory, tulip trees and catkins and in the southern states magnolias.

The area between the deciduous forests to the east and the Rocky mountains to the west, the prairie, is naturally wooded. In the east (with an annual rainfall of 500–900 mm), tall perennial grasses dominate in the genera spring grass, Andropogon and drip grass (Sporobolus). In the shade of the Rocky Mountains (with an annual rainfall of 300–500 mm), there are short grass prairies with gram grass, buffalo grass and even small cacti. The prairie is now largely cultivated with wheat and maize, among others.

In Mexico, there are northern elements, including many pines and oaks, and tropical vegetation types, ranging from desert to rainforest. Cactus plants predominate in arid areas. In Central America and the Caribbean islands cone trees are found. Rainforests in Central America are probably the world's richest ecosystems.

Wildlife

The nectaric region has a fauna similar to that of Eurasia, but is much richer. In particular, crawfish and starless amphibians are numerous. This is partly due to the fact that the north-south oriented mountain ranges have not prevented the animals' retreat from expanding inland ice, unlike the transverse Eurasian mountains. Some South American features are also available. North America (north of Mexico) houses up to 400 mammals, 835 birds (of which 650 breed), 285 crustaceans and 195 mammals. Pronghorn, three gnagarfamiljer ( ekorrbävrar, gophers and kindpåsspringmöss), heloderma, grävnosödlor (genus Anie'lla) and some fish families (including arctic foxes, dwarf moths, cave fish, and sunfish) are endemic.

The fauna of the North American tundra and taig is very similar to that found in Eurasia. The tundra includes muskox, caribou (the North American subspecies of reindeer) and polarhare and mountain fox. Here and in the taiga there are also snowshoes, which is the most important prey for Canadian fluff. There are also North American tree bears (Erethizon dorsatum), North American beaver, white-headed sea eagle (United States national bird) and several species of yarns. Several species of Pacific salmon migrate into the rivers to play each year, which leads to Grizzly bears and white-headed sea eagles can sometimes be collected locally in large numbers. The coastal rainforest along southern Alaska and British Columbia is home to, for example, squirrels and the increasingly rare spotted owl ( Striʹx occidentaʹlis). In the Rocky Mountains you will find, among other things, the snow, thicket sheep, black bear, cougar and pipe sharks. In the eastern deciduous forest area, white-tailed deer, North American opossum (pointy rat), raccoon, mink, turkey, many woodsmen and monarchs are widespread.

The large prairie along central North America is practically fully cultivated today. The huge bison herds of bison have been decimated into small flocks within scattered reserves. Still, however, there are prairie wolves, skunks, the peculiar fork antelope, prairie dogs (increasingly rare), ground squirrels, cheetah rats, prairie owl, tooth quail and prairie hens. Californiakondor, North America's largest terrestrial bird, stood when the extinction limit but breeding programs have become so successful that the species now exists freely in Arizona, Utah (including in the Grand Canyon), California and Baja California.

The deserts of the southwestern United States and northern Mexico harbors åsneharar, many rodents (eg kangaroo rat), ring-tailed cat, fox, rooster cuckoos (long-legged, ground-living ödlejägare), rattlesnakes and the poisonous Gila monster.

The cold currents off the west coast of North America mean that wildlife is rich with, among other things, two species of sea lion, northern sea elephant (Mirounga angustirostris) and sea otter. Here, white shark and killer whale also regularly patrol, and during the winter months gray whales stay in the area around the California peninsula.

Around the Florida peninsula in the southeast, there are tropical features of the fauna, such as a lizard crocodile, Mississippi alligator, lamantine (a sea cow) and many marshland birds. There is also a subspecies of cougar (here called the Florida panther), now very rare.

Natural Resources

North America has significant assets of almost all metals. Deficiency mainly prevails on chrome ore. In the urban areas there are iron, nickel, platinum, gold, silver, copper, tungsten, lead and zinc ores. In addition to the alloys (mainly molybdenum in Colorado), the Cordillaries contain gold and silver (mainly in Mexico) and mercury. Significant lead and zinc resources are found in sedimentary deposits in the Mississippi Basin. The major Antillean assets are cobalt and nickel (Cuba) and bauxite (Jamaica).

Of non-metals, North America has the world's largest potassium carbonate (potash) reserves in Saskatchewan. Check more on Countryaah.

The energy resources are dominated by uranium (Canada and the US - primarily the Colorado Plateau) and oil (USA and Mexico) and gas (USA). Oil shale (USA) and oil sands (Canada) are other important oil resources. At least 20% of the world's coal reserves should be found in North America. Hydropower assets are relatively large, mainly in the Cordillarians. Geothermal energy and peat are essential assets.

The freshwater is insufficient in North America's arid regions, in some agricultural districts and in many metropolitan regions, e.g. Mexico City. Large pipeline systems bring water to California; In dry areas such as Arizona, relative water (fossil groundwater) is exploited. Dirt is a major problem in areas with good water resources.

The tajgan is in North America the most economically important natural vegetation type. Of the temperate grasslands, especially the prairie, little remains in the natural state. The same goes for the prairie's original bison herds. The Prairie is today North America's most important agricultural area. The basis for the region's cultivation lands is loose soil. The area has extensive soil erosion, mainly wind erosion. Alluvial soils are important cultivation lands especially in Central America and the Greater Antilles. The fishing waters off Labrador as well as in the Caribbean, where seafood is significant, are among the world's most important.

Countries in North America
  1. Antigua and Barbuda
  2. Bahamas
  3. Barbados
  4. Belize
  5. Canada
  6. Costa Rica
  7. Cuba
  8. Dominica
  9. Dominican Republic
  10. El Salvador
  11. Greenland
  12. Grenada
  13. Guatemala
  14. Haiti
  15. Honduras
  16. Jamaica
  17. Mexico
  18. Nicaragua
  19. Panama
  20. Saint Kitts and Nevis
  21. Saint Lucia
  22. Saint Vincent and the Grenadines
  23. Trinidad and Tobago
  24. United States

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