Geography/the Americas

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North America[edit]

North America extends in a north-south direction, following the course of the Rocky Mountains and similar ranges. Its southern limit is the Panama Canal, and its northern end is the Arctic Ocean.

The southern part of the continent, called Central America, is tropical, and while it includes some mountains, it is narrow so it does not have large highlands, broad mountain ranges, and long rivers. This changes to the north, however, in Mexico, where the highest peaks reach approximately 20,000 feet (6,100 m) and the center of the continent is covered in dry highlands, where there are many mountain ranges. To the north, the mountain range gets wider (and is called the Rocky Mountains), and then gets narrower again towards Alaska.

North America is generally high and mountainous in the west, and lower in the east. The highest peak is a long way north, though; it is now officially called Denali but often goes by older name as well, Mount McKinley. This peak, however, is lower than the highest peak in South America (Aconcagua) and of course is lower than the highest mountain peaks in the Himalayas in Asia.

On the eastern side of the North American continent, large gulfs and bays create a varied coastline; the largest are the Gulf of Mexico and the Hudson Bay; the western coast has only one inlet of this size or nature, the Gulf of California. North of the Gulf of Mexico are two important landforms, the Mississippi River Basin and the Appalachian Mountains. The Mississippi River and its longest tributary, the Missouri River, dominate the central part of North America, and their location marks one of the world's largest flat areas, between the Rockies and the Appalachians. The Appalachians, while they are long, are not very high, and in height they are more the Great Dividing Range than the Rocky Mountains.

Flowing from the Great Plains (the area on the northern side of the Mississippi River Basin) to the north toward the Arctic Ocean is the Mackenzie River, which flows through two large lakes, the Great Slave Lake and the Great Bear Lake, before it meets its final destination. There is another large group of lakes on the eastern side of the North American continent, to the northwest of the Appalachians, which ironically is called the Great Lakes: the lakes in this group are Lake Superior, Lake Michigan, Lake Huron, Lake Ontario, and Lake Erie. These are among the largest lakes in the world, and it is quite amazing that five lakes of such great size would all be so close to each other, and yet another wonder that the total number of gargantuan lakes in North America is high as seven (including the Great Bear and Great Slave Lakes).

Various smaller features along both coasts exist, often as parts or ends of estuaries. The San Francisco Bay marks the end of the Sacramento River and some other smaller streams like the Alameda Creek. This bay has a very narrow inlet, the Golden Gate, that separates the bay from the Pacific Ocean. (The Golden Gate Bridge stands at this point.) To the south of the San Francisco Bay is the wider, less enclosed Monterey Bay, and farther south again is an island group, the Channel Islands, that is separated from the mainland of North America by a relatively narrow strait. Many rivers flow from the Sierra Nevada west (or often southwest) into the Central Valley, meet around the central part of this valley, and then flow west into San Pablo Bay, which is connected to the San Francisco Bay and therefore the Golden Gate and the Pacific Ocean.

On the east is Chesapeake Bay and other, similar features; Long Island, on the eastern side of the New York City, extends outward into the Atlantic Ocean, and so does Cape Cod to the north. The Gulf of Saint Lawrence, farther north again, marks the end of the St. Lawrence River, and to the east of the this gulf is the large island of Newfoundland. To the south, the Florida Peninsula stretches out toward the Bahamas and Cuba.

While the term Rocky Mountains can be applied to the general mountain range on the western side of the United States, more specific terms can be used for the various mountain ranges that go along the western coast of the country. In the state of California, going from north to south on the eastern end of the state, is the high Sierra Nevada Mountain range. The highest peak in this range is Mount Whitney, which is over 14,000 feet (4,300 m) high. The western side of the Sierra Nevada gradually climbs to elevations of this nature, and then quickly goes downhill on the eastern side, making construction of roads and the use of mountain passes difficult. The Sierra Nevada makes the transition to the Cascade Mountains in northern California, and this more volcanic mountain range continues north into Washington state, and it includes such high peaks as Mount Rainier and Mount Saint Helens. On the western side of California are a group of mountain ranges called the Coastal, or Coast, Ranges. These are much lower than the Sierras (with mountain peaks generally in the low thousands of feet high) but in places can have dramatic scenery.

Inland but still on the west-central side of the continent are many large, dramatic canyons, like the Grand Canyon, which is approximately 5,000 feet (1,500 m) deep, and the similarly deep Hells Canyon. Yosemite Valley is also a few thousand feet deep, and while this may sound astonishing, such valleys are quite ordinary in the region.

Greenland is often ignored because it is so far north and has such a small population, but it is actually quite notable. It is northeast of Canada and has some high mountain peaks, reaching above 10,000 feet (3,000 m). Greenland's western coast has many inlets, called fjords, and has some habitable land. Inland, however, is a large ice sheet similar to the one in Antarctica, and this covers most of the island.

Overall, North America is a continent with a little of everything. Even surrounding it are notable geographical features — the island of Greenland is the world's largest island, and to the west of the continent is the world's largest ocean.

Another important factor in North America is climate, which is varied across the continent. A narrow section along the west coast gets a reasonable amount of rainfall, but only a couple hundred miles inland, it is dry, especially in the center-south. The eastern side of North America is wetter, especially in the tropical parts like Florida.

Quiz[edit]

Complete North America quiz.

South America[edit]

South America is a smaller continent than its northern neighbor, but it is still a great, expansive landmass dominated by tropical forests, high mountains, and lower plains.

The northern tip of the continent is around the location of the Panama Canal and the Darien Gap (an place on the North/South American border where there are no roads); it is here that the land suddenly widens to the countries of Colombia and Venezuela, and there are high mountains as there are in North America; this range is the Andes Mountain Range, or just the Andes, and it extends all the way across the continent. There are large plains, forests, basins, deserts, and highlands east of the Andes, but the portion of South America west of the Andes is relatively narrow. On the western side of the range is the Atacama Desert, and on the eastern side of the range are the Guiana Highlands and the Amazon Basin, toward the north, and toward the south Brazil's highland regions and the great expanse of Pampas in Argentina. In the far south is Tierra del Fuego; this land at South America's southern tip is not only associated with fire, but also cold, stormy oceans.

If a person were to walk or, by some means, drive south into South America from the Darien Gap, on the left would be a tropical region slightly north of the equator. (The country of Venezuela occupies much of this region.) To your harder left, would be Lake Maracaibo, and in front of you and slightly to your right would be the northern end of the Andes.

So, there is this land to the left that is tropical, and slightly north of the equator. The Atlantic Ocean and the Caribbean Sea form a coastline along the northern side of this tropical region, gradually sloping down toward an eastward point, in Brazil. Between the point at which South America gets as far east as it possibly can reach, and Lake Maracaibo, is the Guiana Highlands region, where there are some fairly high, but flat-topped mountains. This provides the ideal environment for very tall waterfalls, and waterfalls there are: Angel Falls, which comes off the side of one of these flat-topped mountains, is the highest waterfall in the world.

To the south of the Guiana Highlands is the Amazon River Basin. The Amazon and many other rivers gather here and go east from the Andes toward the Atlantic Ocean. This tropical rainforest region is right around the location of the equator. The basin has a low elevation, unlike the destination where the rivers begin, in the Andes.

The Andes Mountains, or just the Andes, mark the divide between the Amazon River and tributaries and any rivers that flow in the opposite direction, to the west. At the top of the Andes is a high plateau that itself is covered with mountains. Compared to the Amazon Basin, the region at the top of the Andes is cold and dry, but it does have some lakes. Lake Titicaca is known for its high elevation and the people that live around (and, on) the lake.

The land west of the Andes is tropical in the north, but south of the equator, it quite quickly becomes very dry — so dry that it hardly receives any rain at all. This is the Atacama Desert, which is in the country of Chile.

Meanwhile, on the other side of the Andes, the tropical land gradually changes to grassland. Along the way are some highlands, and in Rio de Janeiro, for example, it is quite mountainous. To the south, however, is Uruguay, which is much flatter. South again in Argentina, the grassland is good ranching country, but going south again, gives way to desert. In Chile, however, the opposite is the case; as one goes south, it gets wetter.

The southern end of the continent is colder and is quite close to Antarctica. The continent is narrow (east/west) here. The Strait of Magellan and Tierra del Fuego mark the southern end of South America, before the Southern Ocean and then Antarctica's northern end. East of South America's southern tip are some islands, including the Falkland Islands and the South Georgia Islands.

Quiz[edit]

Complete South America quiz.