3.Relief.

The relief of the continent is not very complicated but rather varied. There are mountains, plains and lowlands. The average height over the sea level is 720 m.

Along the western coast of the continent there are high mountains called the Cordilleras. They consist of several ranges along the coast (the Coast Ranges) and further into the continent (the Sierra Nevada, the Rocky Mountains, and the Cascade Mountains). In the east the Appalachian Mountains run. The highest mountain is McKinley (6 194 m). The highest volcano is Orizaba (5 747 m).

There are also some lowlands: the Mississippi Lowland, the Preatlantic Lowland, the Premexican Lowland and the Central Plains.

North America is rich in gold, copper, uranium, polymetallic ores, oil and gas.

4. Climate.

The continent crosses all climatic belts but equatorial. The greater part of it is in temperate zone. In arctic zone winters are severe with heavy snow-falls and violent snow storms. The summer here is cool. The polar nights last for 5 months. Most territories are covered with ice.

The climate of North America depends on winds, relief and oceanic currents. The Cordilleras make the climate of both sides of the continent different. The central part is occupied by the plains, so the tropical air masses move far to the north and the arctic air masses penetrate into the land to the Gulf of Mexico. That is why the weather here is changeable.

The oceanic currents influence the climate mostly in the coastal regions. The warm North Pacific current brings many rainfalls and high t^o. The cold Californian Current cools and dries the territory of California.

The tropical climatic belt is divided into two regions: tropical deserts and tropical wet climate. In subequatorial climatic belt the t^o is high all year round and there are many rains in summer.

Climatic Belts.

(Laboratory Work).

Climatic belt	Geographical position. Relief.	Rainfalls	Winds	Winter t^o	Summer t^o
Subequatorial
Tropical
Subtropical
Temperate
Subarctic
Arctic