Land & Climate

Land

North America covers about 24,249,000 square kilometres, or about a sixth of the world's land area. The continent is roughly triangular in shape. The Arctic, Atlantic, and Pacific oceans border the three sides. At its northern end, North America stretches more than 8,900 kilometres from Alaska's Aleutian Islands to the Canadian province of Newfoundland. At the southern end of the continent, the narrowest parts of Panama are only about 50 kilometres wide. The greatest north-south distance spans about 8,900 kilometres, from northern Greenland to Panama.

Land regions. North America has eight major land regions. They are (1) the Pacific Ranges and Lowlands, (2) the Western Plateaus, Basins, and Ranges, (3) the Rocky Mountains, (4) the Interior Plains, (5) the Canadian Shield, (6) the Appalachian Highlands, (7) the Coastal Lowlands, and (8) Central America and the Caribbean.

Pacific Ranges and Lowlands consist of two parallel mountain ranges separated by a series of valleys. The mountains extend all the way from Alaska to Mexico. Fertile valleys between the mountain ranges are productive agricultural centres. The outer ranges include the Olympic Mountains in Washington and the coastal mountains of Oregon and California. The inland ranges have the continent's tallest peaks and some of its most spectacular scenery. Mount McKinley, North America's highest mountain, rises 6,194 metres in the Alaska Range. The inland mountains also include the Cascade Range, which has many volcanic peaks, and the Sierra Nevada of California. Much of this ruggedly beautiful area is preserved as national, state, and provincial parks.

The Western Plateaus, Basins, and Ranges lie between the Pacific ranges and the Rocky Mountains. This dry region includes the Yukon River Basin in Alaska and Canada, the Interior Plateau of British Columbia, the Colorado Plateau, the Great Basin centred in Nevada, and the Plateau of Mexico. Much of the copper, gold, lead, silver, and zinc produced in North America comes from this region. Its land features include the spectacular Grand Canyon. The lowest point in the Western Hemisphere is in Death Valley in California. It is 86 metres below sea level.

The Rocky Mountains form North America's largest mountain system. They run from Alaska to New Mexico, and extend southward into Mexico as the Sierra Madre Oriental. Thick forests cover the northern slopes, and the southern Rockies have rich deposits of minerals. The Rockies' scenic peaks make the region a popular recreation and tourist area.

The Interior Plains cover much of central Canada and the Midwestern United States. The eastern part of this flat, low-lying region is North America's most productive agricultural area. Maize and pigs rank among the leading products. The drier western part--the Great Plains--supplies most of the continent's wheat and much of its cattle, and essential energy resources such as petroleum and natural gas.

The Canadian Shield is a huge area of ancient rock that covers most of Canada east of the Great Plains and north of the Great Lakes. Few people live in this region because of the poor soil and cold climate. Many valuable minerals lie beneath its surface. Evergreen forests spread across the southern part of the region.

The Appalachian Highlands extend from Newfoundland to Alabama. The region includes low, rounded mountains; plateaus; and valleys. One of the world's most productive coal fields lies in the Allegheny Plateau, in the central part of the region. Hardwood forests grow in the northern and southern sections.

The Coastal Lowlands stretch along the Atlantic Ocean and the Gulf of Mexico, from New York City to Mexico's Yucatan Peninsula. The rich soil in much of this region creates good farmland.

Central America and the Caribbean consist of the narrow bridge of land at the southern tip of North America and the islands in the Caribbean Sea. A chain of volcanoes forms a mountainous spine along the Pacific coast of Central America. Most of the Caribbean islands were created by volcanic eruptions. Others are coral and other limestone formations.

Rivers.
West of the Rocky Mountains, the rivers of North America drain into the Pacific Ocean or the Gulf of California, an arm of the Pacific. East of the Rockies, rivers flow into the Arctic Ocean, Hudson Bay, the Atlantic Ocean, or the Gulf of Mexico. The high ridge of the Rockies that separates the waters is called the Great Divide, or the Continental Divide.

West of the Rockies, such rivers as the Yukon, Fraser, and Columbia rush to the Pacific through gaps in the coastal ranges. The Colorado River cuts through the Grand Canyon as it flows toward the Gulf of California.

The Mackenzie River, which forms part of Canada's longest river system, flows from Great Slave Lake into the Arctic Ocean. Many Canadian streams and rivers empty into Hudson Bay. East of the Appalachian Mountains, several short rivers, such as the Connecticut and the Hudson, drain into the Atlantic.

The continent's longest river system, the Mississippi-Missouri-Ohio, flows into the Gulf of Mexico. This system, which is about 7,600 kilometres long, drains almost all of the United States between the Rockies and the Appalachian Mountains. The Rio Grande, which forms most of the border between the United States and Mexico, also empties into the gulf.

Lakes.
Lake Superior is the largest freshwater lake in the world. It is one of the five Great Lakes, which make up part of North America's most important inland waterway. Four of the Great Lakes--Superior, Huron, Erie, and Ontario--lie on the border between Canada and the United States. The fifth, Lake Michigan, lies entirely within the United States. A chain of large lakes extends northwest from the Great Lakes to Great Bear Lake, Canada's largest lake. Utah's Great Salt Lake, one of the natural wonders of North America, is saltier than the ocean.

Waterfalls.
North America's most famous waterfall is Niagara Falls, on the U.S.-Canadian border between Lake Erie and Lake Ontario. Niagara Falls consists of two waterfalls, the Horseshoe Falls and the American Falls. The Horseshoe Falls is only 51 metres high, but more water passes over it than over any other waterfall in North America. A number of higher falls--several more than 300 metres high--plunge through the Cascade Range and the Sierra Nevada. North America's highest waterfall, Yosemite Falls, is a main attraction at Yosemite National Park in the Sierra Nevada. Yosemite Falls drops 739 metres.

Deserts.
Most North American deserts lie in the Southwestern United States and northern Mexico. One vast dry area reaches from southern Idaho and Oregon into Mexico. It includes the Great Basin, the Mojave Desert and Death Valley, and the Sonoran Desert. Another area, the Chihuahuan Desert, extends from southern New Mexico through western Texas into Mexico.

Coastline and islands.
North America has a longer total coastline than any other continent. Including the continent's many islands, the coastline is about 300,000 kilometres long.

Mountains line the Pacific and north Atlantic coasts, and many bays cut into the rocky land. Plains slope gently to the coasts along the Gulf of Mexico, the Caribbean Sea, and the Atlantic south of New York City. There, the coastline is relatively smooth and even.

A number of islands lie off the coasts of North America. Greenland is located in the North Atlantic Ocean. Although Greenland is part of North America, it is governed as a province of Denmark. Newfoundland and other islands lie off the Canadian coast in the Atlantic Ocean. In the Pacific Ocean, Vancouver and many other islands lie off Canada, and the Aleutian Islands extend westward from the tip of the Alaska Peninsula. The islands in the Caribbean Sea are called the West Indies. They include the Bahamas, the Greater Antilles, and the Lesser Antilles. Cuba, one of the Greater Antilles, is the largest Caribbean island.

Climate

North America is the only continent that has every kind of climate, from the dry, bitter cold of the Arctic to the steamy heat of the tropics. An icecap permanently covers the interior of Greenland, where the temperature almost never rises above freezing.

In the North American tundra, the vast treeless plain of the far north, the temperature rises above freezing for only a short period each summer. In the low-lying areas of the far south, it is hot and rainy all the time.

Most of the rest of North America is cold in the winter and warm in the summer, with moderate precipitation. ome areas have mild winters and long, hot summers. Other areas have harsh winters and short summers. The highest temperature ever recorded in North America was 57 °C at Death Valley in 1913. The lowest temperature was -66 °C at Northice in Greenland in 1954.