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North America is the third largest continent (1990 est. pop. 365,000,000), c.9,400,000 sq mi (24,346,000 sq km), excluding Eurasia and the northern of the two continents of the Western Hemisphere. <ref name="def">the second largest country in area in the world), U.S.A., Mexico, Greenland (Danish territory), Saint Pierre and Miquelon islands (a small French overseas department) and Bermuda (British dependency). Retrieved on 2006-10-11.</ref>. It is bounded by the Pacific Ocean on the west, the Atlantic Ocean on the east, the Caribbean Sea, Atlantic and Pacific oceans, and South America on the south, and the Arctic Ocean on the north. Canada covers most of the northern half of North America (much of which is sparsely populated). Alaska, the largest state of the U.S.A., occupies the northwestern part of the continent.

The first inhabitants of North America have supposedly come from Asia at least 20,000 years ago, some of which believes to have come over the Bering land bridge. Europeans, such as Christopher Columbus and many others made discoveries to North America. "Most people live in towns and cities with larger cities along the east and west coasts."<ref name="abc">North America is the third largest continent, extending from the Arctic to the tropics and covering 24 million km² / 9.4 million mi². It is divided in Asia by the Bering Strait. Retrieved on 2006-10-11.</ref>

North America consists of all the mainland and related offshore islands lying north of the Isthmus of Panama (which joins with South America). "Anglo-America" can describe Canada and the USA together. "Middle America" is used in reference to the region of Mexico, the republics of Central America, and the Caribbean.

Its natural features include the Rocky Mountains, the Appalachian Mountains (the largest mountains on the east), the Great Lakes, and the Mississippi, Missouri, Rio Grande, and St Lawrence rivers.

Climate is mainly determined, on a large extent, on the latitude, ranging from the arctic cold in the north, and tropical heat in the south. The western half of North America tends to have wilder and wetter climate than other areas with equivalent latitude, although there are steppes (known as "prairies") and deserts in the "American Southwest" (Arizona, Colorado, California, Nevada, New Mexico, Utah, Oklahoma, Texas), along with neighboring parts of Mexico.

Contents 1 Geographic interests 2 History 3 Coastal line 4 Surface and climate 4.1 Hydrography 4.1.1 River systems 4.1.2 Water 4.2 Climate and vegetation 5 Human interaction 6 Zoology 7 Mineralogy 7.1 Rocky Mountains 8 Deserts of North America 8.1 Specific regions in the West 9 References 9.1 Notes 10 See also 11 Other topics 12 Bibliography

[edit] Geographic interests

To the northwest, North America and Asia separates by 56 miles at the Bering Strait. <ref name="abc"/>. To the northeast, Greenland is 300 miles off the European island of Iceland.

North America features the Mississippi-Missouri river system, with a drainage basin of 1,221,000 square miles. Plant life in the arctic consists mainly of grasses, mosses, and arctic willows. Coniferous trees such as spruce, pine, hemlock, and fir are indigenous to the Canadian and Western U.S. mountain ranges as far as San Francisco.

[edit] History

Physiographic ally, the continent may be divided into at least five major regions: the Canadian Shield, which is a geologically stable area of ancient rock that occupies most of the northeastern quadrant, including Greenland; the Appalachian Mountains, a geologically old and eroded system that extends from the Gaspé Peninsula to Alabama; the Atlantic-Gulf Coastal Plain, a belt of lowlands widening to the south that extends from South New England to Mexico; the Interior Lowlands, which extends down the middle of the continent from the Mackenzie Valley to the Gulf Coastal Plain including the Great Plains on the west and the agriculturally productive Interior Plains on the east; and the North American Cordillera, a complex belt of geologically young mountains and associated plateaus and basins, which extend from Alaska into Mexico and includes two orogenic belts—the Pacific Margin on the west and the Rocky Mountains on the east—separated by a system of intermontane plateaus and basins.<ref name="ghi">Jones, Steve. North America's Geology and Geography. USA Today. Retrieved on 2006-08-19.</ref>. The Coastal Plain and the main belts of the North American Cordillera continue in the south in Mexico (where the Mexican Plateau, bordered by the Sierra Madre Oriental and the Sierra Madre Occidental. It is considered a continuation of the intermontane system) to connect the Transverse Volcanic Range, a zone of high and active volcanic peaks south of Mexico City.

During the Ice Age of the late Cenozoic era, a continental ice sheet covered much of the continent, centered west of Hudson Bay (the floor of which is slowly rebounding after being depressed by the great weight of the ice). Glaciers descended the slopes of the Rocky Mountains and those of the Pacific Margin. Extensive glacial lakes, such as Glacial Lake Missoula, Bonneville (see Bonneville Salt Flats), Lahontan, Agassiz, and Algonquin, formed by glacial melt water. "Remnants of them are still visible in the Great Basin and along the edge of the Canadian Shield in the form of the Great Salt Lake, the Great Lakes, and the large lakes of west central Canada."<ref name="ghi"/>

[edit] Coastal line

The east coast of America resembles the opposite coasts on the other side of the Atlantic. The vast majority of North America is located on the North American Plate, with parts of California and western Mexico forming the partial edge of the Pacific Plate; the two plates meet along the San Andreas fault.

The continent can be divided into four great regions (and sub regions): the Great Plains stretching from the Gulf of Mexico to the Canadian Arctic; the geologically young, mountainous west, including the Rocky Mountains, the Great Basin, California and Alaska; the raised but relatively flat plateau of the Canadian Shield in the northeast; and the varied eastern region, which includes the Appalachian Mountains, the coastal plain along the Atlantic seaboard, and the Florida peninsula.<ref name="abc"/> Mexico and its long plateaus and cordilleras fall largely in the western region, although the eastern coastal plain does extend south along the Gulf.

The western mountains have split in the middle, into the main range of the Rockies and the Coast Ranges in California, Oregon, Washington, and British Columbia with the Great Basin (a lower area containing smaller ranges and low-lying deserts) in between. The highest peak is Denali in Alaska.

The United States Geographical Survey states that the geographic center of North America is “6 miles west of Bata, Pierce County, North Dakota” at approximately 48⁰ 10′ north, 100⁰ 10′ west, approximately 15 miles (25 km) from Rugby, North Dakota. The USGS further states “No marked or monumented point has been established by any government agency as the geographic center of the 50 States, the conterminous United States, or the North American continent.”<ref>Physical Geography of North America. Retrieved on 2006-08-19.</ref> Nonetheless, there is a 15 foot (4.5 m) field stone obelisk in Rugby claiming to mark the center. Three countries (Canada, the United States, and Mexico) make up most of North America's land mass; they share the continent with 34 smaller nations located mainly south of Mexico and in the Caribbean.

[edit] Surface and climate

The Rocky Mountains stretches from north to south, in contrast to South American cordilleras lean on, west, elevated plateaus, which helps to develop large-sized rivers; less high and send to the east more expanded ramifications. The mountain systems do not allow indefinite connection with the cordillera system with exceptions. They lie in chains parallel to the nearest coasts in North America.<ref name="ghi"/> These are named the Appalachians or Alleghenies.

The Great Plains	Saint Lawrence River on the New York-Ontario border	The Upper Rio Grande by Creede, Colorado	The Columbia River from Canada to the Pacific
A vivid showcase of the Pacific Ocean from Pebble Beach, California

In North America, there is about one-half of the Great Plains. The narrow plains in the Mexican coast and the savannas of the Mississippi are analogous to, respectively, the Patagonian steppes and the pampas of the Piranha, Paraguay, and Rio de la Plata. Thus the Appalachians and the mountain chains of Brazil are regarded as creating similar interruptions to the plains community.<ref name="jkl">North America climate. Retrieved on 2006-08-19.</ref>.

North America extends to within 10° of latitude of both the equator and the North Pole. It embraces every climatic zone, from tropical rain forest and savanna on the lowlands of Central America to areas of permanent ice cap in central Greenland.<ref name="jkl"/>. Sub arctic and tundra climates prevail in north Canada and north Alaska, and desert and semiarid conditions are found in interior regions cut off by high mountains from rain-bearing westerly winds.<ref name="abc"/>. However, most of the continent has temperate climates very favorable to settlement and agriculture. Prairies, or vast grasslands cover a huge amount in mountain ranges.<ref name="abc"/>

Below is a list of North America's greatest snowfalls.

Greatest Snowfalls

	Places	Date	Inches	Centimeters
24 hours	Silver Lake, Colorado	April 14–15, 1921	76	195.6
1 month	Tamarack, California	Jan. 1911	390	991
One storm	Mt. Shasta Ski Bowl, Calif.	Feb. 13–19, 1959	189	480
One season	Mount Baker, Wash	1988-1999	1, 140	2, 895.6

[1]

[edit] Hydrography

[edit] River systems

North America has the most extensive lake groups in the world. The Mississippi, or preferably, the Mississippi-Missouri is the largest North American River.<ref>Longest River in North America. Retrieved on 2006-08-19.</ref>. Its size is 1,221,000 square miles. Among the MR, is the St. Lawrence River, which is at length is 600, 000 square miles and just like the MR, opens up the "heart" of the continent, while other rivers cross the northern plains.

The Mississippi River is called the Father of Waters since it is one of the largest rivers in the world. Including its major tributary, the Missouri River, which rises in the Rocky Mountains, the Mississippi is 3,892 miles long. Its river basin drains 2/5ths of the Continental United States, which is 1/3 size of Europe. The Mississippi rises in several small lakes in Northern Minnesota at 1,670 ft above sea level.<ref name="ghi"/> It gets larger, as it flows into the Gulf of Mexico. Then it is joined first by the Missouri River, and next by the Ohio and many smaller rivers flow into it.

High bluffs borders the wide stream of the Mississippi in central U.S. It is thought that ancient glaciers melted, and streams fed by melted ice cut the deep valley in the upper MR. Gradually, their streams carved the sloping, wooded hills that goes into the bluffs. Seventeen miles north of St. Louis, the MR, joins the Mississippi side by side. A little north at Cape Girardeau, the bluff ends. Next, it flows through its alluvial valley. Along this valley, centuries of mud deposits have built up the bottom and natural levees alongside the river. In places, surface of MS lays above land, which can result in disastrous floods over the riverbank. It has always been a threat to people alongside the river.

From then on, it enters the delta area, which is 12,000 square miles, and stretches out into the Gulf of Mexico in the shape of a bird's foot (although this shape consists of very low-lying land, which is in the process of getting flooded). In 1882, the U.S. government contributed to the new levee system. They built 8ft wide and 150ft at the bottom, 15-25 ft high-level banks. As forests chops away and swamps drained, floods increased in the river. (For example, the 1926 flood that lasted along the river and grew higher). The flood covered over almost 23,000 square miles of land, killing hundreds. Federal and state governments set up a flood control plan that included building stronger and higher levees and creating dams and spillways to divert floodwaters into other channels. Then forests replanted in order to hold moisture in the ground, and curves in the river straightened.

Other main North American rivers include the Mackenzie and Copper mine, approaching the Arctic Ocean, the Churchill, Nelson River Nelson, Severn, and Albany. Then it enters the Hudson Bay, the St. Lawrence River, Rio Grande, Magdalena, Colorado. Followed by entering the Atlantic; and the Yukon, Fraser, Columbia, Sacramento, San Joaquin, and last entering the Pacific.<ref name="abc"/><ref name="ghi"/>

[edit] Water

Water is a major natural resource in North America.<ref name="def"/> In addition, there is high runoff and snowmelt on the landscape. Rocky Mountain Rivers and lakes supply water for one-quarter of the United States. The rivers that flow from the Rocky Mountains eventually drain into three of the world's five oceans: the Atlantic, the Pacific, and the Arctic. Some of the most prolific rivers are the Colorado, the Arkansas, the Columbia, the Missouri, and the Yellowstone.

Water is a main form of energy, a valuable resource that wastes frivolously. Fresh, clean water can be scarce. This can increase dehydration. Less than 3 percent of the Earth's water is fresh, and all but three-thousand of that is locked up in glaciers or icecaps or is too deep in the earth to retrieve. Even the fresh water available in rivers, lakes, and the ground is polluted with biological, chemical, and radioactive contaminants.

[edit] Climate and vegetation

The climate in North America is typically cool and humid. The rainy zone disproportionately extends in America, and as the continent stretches over the climatic zones, vegetation is remarkably distinctive. Great indentations of the shoreline make insular conditions to prevail in much of its interior. The area along the west coast tends to be milder and wetter than other areas with the same latitude.<ref name="abc"/>

There are various plant life distributions in North America. Plant life in the arctic includes grasses, mosses, and arctic willows. Coniferous trees, including spruces, pines, hemlocks, and firs, are indigenous to the Canadian and Western U.S. mountain ranges as far as San Francisco. Among this includes giant sequoias, redwoods, great firs, and sugar pines. Sugar pines confine on the northwestern area of the United States. The central region of the country has hardwoods. Southern states grow extensive yellow pines. In addition, goods such as mahogany, logwood, and lignumative are sells. These are tropical.<ref name="abc"/> The southwest has desert plants that are yucci and cacti. The cultivated native plants of North America is tobacco, maize, potato, vanilla, melons, cacao, gourds, indigo plant, and beans. <ref name="abc"/>

[edit] Human interaction

In the Western Hemisphere, remains of coral reefs lie in Florida, which are estimated to be 10,000 years old; and a skeleton dug up in the Mississippi Delta (in buried forests), near New Orleans, is supposed to have lain there 50,000 years ago. These artifacts could prove that man existed in America prehistorically. New mixed races are distinguished by a variety of names (e.g., Mestizos, Mulattoes, and Zambos, and native ancestors of European parents called Creoles.<ref>After Columbus's "discovery" of the New World, Europeans arrived, devastating the Native Americans, drawing borders, and clashing with each other. Retrieved on 2006-10-11.</ref>.

In 1960, the population of North America estimated at 405,000,000 persons. Now, North America is the fourth largest continent by population. <ref name="abc"/>

[edit] Zoology

America has many animals that are native to it, such as the species of bear (the grizzly being most midable), the wolf, and deer, the bison and musk ox, with special kinds of squirrel. These include the opossum and raccoon. Central America has adapted sloths, anteaters, and armadillos. Other animals includes the condor, among the heights of the Andes, the parrots and the monkeys of Tropical forests, the humming bird, rattlesnake, alligator, and Cayman of the banks of the streams, the electric eel in the tropical waters, and swarms of mosquitoes on the wide plains.

[edit] Mineralogy

More than any other area in the world, North America produces the most metals and minerals used by man. Thus this makes Canada, the United States, and Mexico some of the richest regions in the earth.<ref name="def"/><ref name="pqr">North America's extensive agricultural lands (especially in Canada and the United States) are a product of the interrelationship of positive climatic conditions, fertile soils, and technology. Retrieved on 2006-10-11.</ref> <ref name="mno">Economically, North America is one of the wealthiest regions of the world. Retrieved on 2006-10-11.</ref>. However, in the Rocky Mountains mineral resources are often scarce.

[edit] Rocky Mountains

The Rockies known for it is the vast amount of resources has rich minerals that include bauxite, copper, lead, gold, silver, tungsten, uranium, and zinc. Coal, petroleum, and natural gas are other minerals to be found there in Wyoming.<ref name="pqr"/><ref name="mno"/> Wakes of toxic wastes dot and mine tailings the Rocky Mountain landscape. In one major example, eighty years of zinc mining polluted the river and bank near Eagle River in north-central Colorado. A high concentration of the metal carries off by spring runoff.

Agriculture and forestry are two major industries. Agriculture includes arid land and irrigated farming and livestock grazing.<ref name="def"/> This provides you with some of the richest crops throughout the year.<ref name="mno"/> Livestock are often moved between high-elevation summer pastures and low-elevation and winter pastures.

[edit] Deserts of North America

The desert makes up a large part of the United States. From the northern part of Mexico through the southwest and west parts of the U.S., the land is typically arid and sandy, has little vegetation, and inhabitates few animals. Nuclear tests often occurs in the American deserts, and airplanes are commonly stored there when mothballed because the dry climate lessens the risk of deterioration

Relief maps of the United States partially show why deserts come to exist. The Sierra Nevada and Cascade mountain ranges run along the entire Pacific Coast, acting as a barrier to the humid winds that sweep off in the ocean. The winds leave their moisture in the form of rain on the western slopes of the mountains, with some areas receiving more than 70 inches of rainfall per year. As a result, the air has moisture and becomes hot and dry when it reaches the east land of the mountains.<ref name="abc"/> These winds that form from mountains conclude the large deserts in the United States and Mexico. Despite this, rain does not usually help plants from leaking water off the land and becoming lost.

Another cause of deserts is the pattern of motion of the Earth's atmosphere. In regions 15 to 30 degrees north and south, air sinks, making it warmer and drier.<ref name="jkl"/> This movement creates the deserts in North America as well as in Africa, Asia, and Australia.

[edit] Specific regions in the West

Most of the Columbian Plateau forms by volcanic action millions of years ago. Lava at once poured out of vast cracks in the earth and covered the land. In some places, lava was 7,000 feet deep. With accurate water, the lava beds remain as a good source of crop growth.

South of the Columbian Plateau is the Great Basin, which is a 200,000-square-mile region between the western wall of the Sierra Nevada and the Rocky Mountains. It includes all or parts of Oregon, Idaho, Nevada, Utah, and California. The Great Basin is a rocky desert, eroded by winds, divided into valleys by rugged mountain ranges, with little rainfall, and no other waters find their way to the sea. Formerly much of the Basin was covered in large salt lakes. The largest was Lake Bonneville, which was 1,000 ft. deep. Now only a small part of the area that was Lake Bonneville contains any water at all, that is named the Great Salt Lake. The remaining area is now long, flat and dry. These flats are used as tracks where automobile speed trials are run.

Another famous desert area in the Great Basin is Death Valley. It received its name when a clique of miners attempted to cross the valley as a shortcut and became lost. It was nearly 2,000,000 acres, and was made into a national monument in 1933. Its lowest point, Badwater, is 282 feet below sea level. In the summer, the temperatures of Death Valley rival the Sahara, climbing as high as 134 degrees Fahrenheit. The only water located there is in salt pools.

Another desolate region is the Mojave Desert which lies south of Death Valley. It covers 15,000 square miles and has dry lakes, desert valleys, and barren mountains that rest on lava base. Like Death Valley, the Mojave contain gold and remarkable deposits of borax.

Arizona as well contains many desert areas, the best known being the Grand Canyon. The vast canyon is over 200 miles long and about a mile deep, and has been cut into layers of rock by the Colorado River. The Grand Canyon is four miles wide at its narrowest point and as wide as 18 miles in some places.

[edit] References

• 1. "Deserts of America". The Golden Treasury of Knowledge 4, book 13: 1008-1091. (1961). Fratelli Fabbri. 61-10594. Retrieved on 2006-08-19.

• 2. "Geography of North America". Universal World Reference Encyclopedia 11, book 1: 231-233. (1964). V.S. Thatcher. 64-12955. Retrieved on 2006-08-19.

[edit] Notes

<references/>

[edit] See also

• Central America
• South America

[edit] Other topics

[edit] Bibliography

Map and aerial photos

• North America map
• Physical map
• Map of the Great Lakes
• North American map
• North America Political map

• Oldest Human Remains in North America Found
• T. H. Clark and C. W. Stearn, The Geological Evolution of North America (1968)
• W. P. Cumming et al., The Discovery of North America (1972)
• R. C. West et al., Middle America: Its Lands and Peoples (3d ed. 1989)
• T. L. McKnight, Regional Geography of the United States and Canada (1992)
• S. Birdsall, Regional Landscapes of the United States and Canada (4th rev. ed. 1992)
• T. Flannery, The Eternal Frontier: An Ecological History of North America and Its Peoples (2001)
• A. Taylor, American Colonies (2001).

es:Geografía de América del Norte