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 other mountain ranges. North America's southern limit is the Panama Canal, and its northern end is the Arctic Ocean.

The southern part of North America, 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. If you traveled north along the course of the Rocky Mountains, you would notice that the mountain range gets wider and narrower in various places.

Generally, North America is high and mountainous in the west, but lower in the east. However, the highest peak is a long way north; it goes by two names: Mount McKinley, its older name, and Denali, the name more recently assigned to the mountain. Although Mount Denali is highest in North America, it is lower than the highest peak in South America (that being Aconcagua); and, of course, Denali is lower than the highest mountain peaks in the Himalayas of 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. (However, Cape Cod and Chesapeake Bay are also notable.) The western coast has only one inlet of this 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 the location these rivers cover marks one of the world's largest flat areas, which lies between the Rockies and the Appalachians. The Appalachians, while they are long, are not very high, and in height they are more like the Great Dividing Range than the Rocky Mountains.

Flowing from the Plains to the north toward the Arctic Ocean (through Canada) is the Mackenzie River, which flows through two particularly large lakes, the Great Slave Lake and the Great Bear Lake, before it meets its final destination. Besides these two lakes, there exists another group of five large lakes in North America. These lakes are northwest of the Appalachians and are collectively called the Great Lakes. The lakes in this group—Lake Superior, Lake Michigan, Lake Huron, Lake Ontario, and Lake Erie—are among the largest lakes in the world. Amazingly, the five Great Lakes are all in close proximity to each other, and including the two lakes mentioned earlier in the paragraph, the total number of extremely large lakes in North America is seven.

Various smaller geographical features along both coasts exist, often as parts, ends, or continuations of estuaries. The San Francisco/San Pablo Bay marks the end of the Sacramento River, along with some other, smaller streams like Alameda Creek and Coyote Creek. The San Francisco Bay has a very narrow connection to the Pacific Ocean: the Golden Gate. (The Golden Gate Bridge crosses the Golden Gate.) 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 strait. Many rivers flow from the Sierra Nevada west (or, more specifically, often southwest) into the Central Valley, then meet around the central part of this valley, and finally flow west as part of the Sacramento Delta to the San Pablo Bay, which is connected to the San Francisco Bay and the ocean.

On the East Coast 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 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 not only the construction of roads, but also the use of mountain passes, difficult. The Sierra Nevada makes the transition to the Cascade Mountains in northern California; the Cascades, a 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 a couple 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, a depth not rare for valleys and canyons in this region.

In any forms of study, Greenland is often ignored because it is so far north and has such a small population, but it is actually quite notable in geography. It is northeast of Canada and has some high mountain peaks that pass 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 ice sheet covers most of the island.

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.

Summary[edit]

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.

Quiz[edit]

Complete the North America quiz.

South America[edit]

"We" notice Angel Falls in the distance

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. As we explore South America, let's imagine that, somehow, we could walk through it from north to south and see all the geographical features it has to offer. Since we're walking south, we're facing south, so objects to the right are to the west, and those to the left are to the east.

The northern tip of the continent, where the journey begins, is around the location of the Panama Canal and the Darien Gap (a place on the North America/South America border where no roads exist); it is here that we begin to walk south. As we walk and leave Panama behind, the narrow isthmus we're standing on suddenly widens out to the countries of Colombia and Venezuela, and we can see high mountains like those that exist in North America. The mountain range we've discovered 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 Andes 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. However, we can't see Tierra del Fuego yet, since it is too far away. Since we are still just south of the Darien Gap, our sight limits us to a relatively small part of South America. On the left (east) is a tropical region slightly north of the equator. (The country of Venezuela occupies much of this region.) To your harder left (east) is Lake Maracaibo, and in front of you and slightly to your right (west) is the northern end of the Andes.

The land to your left (again, the east) 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 going southeast toward an eastward "land's end" 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, though flat-topped, mountains. The mountains provide an ideal environment for waterfalls: 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 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 (in the east/west direction) 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 the South America quiz.