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RELIEF AND MOUNTAINS



About half of the USA territory is covered by plateaus and mountains. The eastern part of the country is occupied by the Appalachian Mountains, which in the north come close to the Atlantic coast and in the south are separated from it by the Atlantic Lowland. West of the Appalachians stretch the Central Plains, the Great Plains, and the Mexican Lowland. The Central Plains are 500-400 m high and have a hilly moraine relief in the north and a more gentle erosional relief in the middle and southern parts. The Great Plains are a deeply cut plateau with the heights of 500m in the east to 1600m at the Cordillera foothills. The flat Mexican Lowland, with the height of up to 150m, is swampy along the Gulf coast and fringed by a strip of marshes. The Cordilleras consist of rows of mountains ranges with the heights of up to 3000-5000m and a broad strip of inter mountain tablelands and plateaus. In Alaska the mountain ranges stretch in the west-east direction and include the Brooks Range, the Yukon Tableland, the Aleutian Range with Mount McKinley, 6193m –the highest peak of the USA and the whole of North America. Rocky Mountains, this system of parallel mountain ranges stretches down the western side of North America from to New Mexico. For long the Rockies cut off the Pacific seaboard of Canada and the United States from the rest of the North America. Within the Rocky Mountains there are many national parks were trees plants animals and birds are protected. The largest of these is the Yellowstone National Park in Wyoming with its great Geysers, its herds of bison, deer, and antelope. Among all the wonders and curiosities of the Rockies, two perhaps deserve mention. One is the grizzly bear, now a rather rare inhabitant, whose fierceness and shyness great size and extreme deftness in moving have made him almost a legendary animal. The other is the great redwood tree with its amazingly tall, straight trunk, branchless for hundreds of feet from the ground.

CLIMATE

North America’s climate is changeable. There are places that are warm all the year round and there are places covered with ice and snow where summer never comes.

The United States occupies a large area in the central part of the North American Continent. Winters in the northern part of the country are long and cold. In the South winters are much shorter. Average temperature in January is mild. As the northern part of the country has such long winters the growing season is quite short.

In the South the growing season is much longer. In fact in some of the states it is nine month long. The climate of these places is affected by other things besides the distance from the Equator. Landforms also affect climate. For example a great belt of mountainous land stretches along the western edge of north America from Alaska south to Panama. Some of these mountains are so high that snow can be seen on their peaks even in summer. Summer days are often bright and warm in the mountains but the nights are cold. The growing season is far shorter than in the lowlands.

Oceans also affect climate. Winters are colder in the interior than along the coasts and summers are warmer. Parts of the Pacific Coast are very wet. The high mountains of this region are responsible for all this rain. They catch the moist air that blows in from the Pacific Ocean.

To the east beyond the mountains there is a vast dry region. This dry land extends from Canada Mexico. But still farther east in the Southeastern United States you can find another wet region. Here warm moist air blows inland from the Atlantic Ocean and the Gulf of Mexico. This all brings plenty of rain to the Southeastern States. The Northern States east of the Mississippi also receive ample moisture.

INLAND WATERS

The longest river in the US is the Mississippi with its tributary of Missouri (7,300km long). The other main tributary of the Mississippi, flowing into it from the east, is the Ohio River. The Mississippi flows to the south and empties into the Gulf of Mexico at New Orleans.

Another important river of the USA is the Hudson River which flows across the north-eastern part of the country and empties into the Atlantic Ocean at New York. The rivers in the west of the country are unsuitable for navigation because they flow through deep canyons and are cut by numerous rapids, which fact, however, makes them a good source of electric power. These rivers start in the Cordilleras and empty into the Pacific Ocean. The largest among them are the Columbia River and the Colorado River.

World – famous is the region of the Great Lakes, situated in the north-east of the United States bordering Canada. It is a system of five great lakes, Superior, Michigan, Huron, Erie and Ontario, joined together by natural channels. The Niagara Falls, great rapids situated on the short Niagara river joined Lakes Erie and Ontario, are famous all over the world and attracts lots of tourists. Buffalo, at the northern end of Lake Erie is the fourth largest port and the seventh industrial city in the United States of America. The lakes can be used only between the months of April and December, as they freeze in winter. The importance of the Lakes is not only commercial: along their shores are vast stretches of forest, meadowland, and grassland, as well as towns, camps, and small country towns.

MINERAL RESOURCES

The USA is rich in coal, iron and oil. There are coal-mines in the Cordillera Mountains, in the Kansas City region and in the east near Birmingham and Pittsburgh. Iron is mined near the Great Lakes and in the Birmingham, Pittsburgh and Philadelphia areas. In California and Texas there are rich oil-fields. There are also deposits of silver and gold.

ECONOMY

The USA is a country of highly developed economy. Heavy industry includes such branches as mining, metallurgical engineering and chemical industries. Detroit is a large motor-car industry centre. Shipbuilding is developed along the Atlantic coast and in San Francisco on the Pacific coast.

Textile industry is also well-developed, especially in the South near large cotton plantations.

Agriculture is very wide-spread, above all in the prairie regions, where wheat and other grain crops are grown.

Cotton is grown in the Mississippi Valley, tobacco in Maryland and Virginia. California is famous for its fruit plantations, and the West-for its cattle-farming. Poultry-farming is wide-spread in the countryside near all big cities.

North America was rich in animal species until explorers from Europe began to visit and set up the feather trade. By the 20th century 70 or more species of animals that had been common disappeared. Bison which were numerous when the Spanish and the French arrived were annihilated in the east by 1825. When railways were built in 1869 vast herds were also killed off in the west. As the Indians depended on their food and skins the white men felt they were killing two birds with one stone the elimination of the bison would make life hard for the Indians.

Control questions:

1. Natural characteristics of the main geographic regions in the USA: New England, Middle Atlantic, South, Midwest, Southwest, West.

2. Describe the climate of the USA? Which parts of the USA have a continental climate? What is characteristics of this climate?

3. The main economic regions of the USA. Mineral resources and their deposits.

4. The role of the USA in the World Economy.

 







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