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The
Beginning
Landforms
Mountains and Hills
Mountains are high and rugged, have an elevation of at least 2,000 feet,
and high relief.
Examples: Sierra Nevada with Mount Whitney (14,495 feet), Salt River Range
of the Rocky Mountains above Star Valley.
Mountains have steep slopes and small summits, and are cold and snowy;
glaciers form on summits.
Mountains have low temperatures, no plants at high elevations, but lower
down there are small plants, and at the bases there are many trees.
They are rich in mineral deposits.
People usually live in the valleys (farming and grazing).
Hills are much smaller than mountains, have an elevation of 500-2,000
feet, and moderate relief usually less than 2,000 feet.
Hills have slopes that are steep but much shorter, and summits are more
rounded.
Farming and transportation are easier in hilly areas, they tend to be
populated.
Example: Berkshire Hills in Massachusetts, "West Hills" of Star
Valley.
Plains and Plateaus
Plains are large areas of flat or gently rolling land, have an elevation
of from less than 1,000 feet to no more than 2,000 feet. Plains above 2,000
feet are called high plains, and have low relief.
There are both coastal and inland plains.
Plains have large populations, many cities, and crops are grown in abundance.
There are plains on every continent except Antarctica.
Plateaus are raised plains, have steep cliffs on one or more sides with
mountains and hills on the other.
Plateaus have elevation of at least 2,000 feet, and low relief less than
500 feet.
Example: Colorado Plateau with elevation of 7,000 to 8,000 feet.
Some plateaus have deep canyons created by rivers, are often windy and
dry, and farming is possible with irrigation.
There are plateaus on most continents.
Bodies of Water
Oceans and Seas
70% of the surface of the earth is water.
Oceans are made up of salt water and are the largest bodies of water on
earth.
Ocean water moves in the form of waves and currents.
Currents are caused by the earth's wind patterns and influence climate.
Ocean water also moves in the form of tides and involve the rise and fall
of the ocean caused partly by the gravitational pull of the moon on earth.
Examples: Pacific, Atlantic, and Arctic.
Seas are bodies of salt water, smaller than oceans, and for the most part
landlocked.
Examples: Bering and Caribbean seas.
Ocean inlets are bays and gulfs, both extend into the land, and bays are
smaller than gulfs.
Examples: Gulf of St. Lawrence and San Francisco Bay.
Many inlets provide harbors for ships.
Lakes and Rivers
Lakes are inland bodies of fresh, standing water.
Lakes are important sources of water for plants, animals, and people.
Most lakes are in areas once covered by glaciers.
North America has more lakes than any other continent.
The largest lakes are the Great Lakes, and the largest Great Lake is Lake
Superior.
Rivers are bodies of fresh, moving water.
Rivers are formed by streams coming together (tributaries).
Continental Divide: east of the divide water flows to the Atlantic, west
it flows to the Pacific.
Examples: Missouri, Mississippi, Snake, Salt, and Columbia rivers.
Physical Regions of North America
Pacific Coast and Islands
Westernmost region of North America, extends from Alaska to Mexico.
High mountain ranges: Alaska Range, Coast Mountains, Cascades, and Sierra
Nevada.
Valleys: Puget Trough, Willamette, San Joaquin, and Imperial valleys.
Islands: Hawaii.
Intermontane Plateaus and Basins
East of Pacific Coast, from Alaska to Mexico.
To the North: the Great Basin (Salt Lake is the largest salt lake in in
North America).
South of the Great Basin lies the Colorado Plateau.
The region is dry because the Pacific Coast Mountains block the rain.
The only deserts in North America are here. Examples: Mojave, Painted,
and Death Valley.
Rocky Mountains
Extend from Alaska to Mexico (Sierra Madre).
Individual ranges make up the system (Salt River Range, Snowy Range, Tetons,
Hoback, etc.).
Here you find conifers and deciduous trees.
Interior Plains and Highlands
Extends from Central Canada to Mexico.
Plains: western part are the Great Plains, eastern are the Central Plains.
Great Plains: land is dry, almost treeless grassland.
Interior Plains and Highlands: rich soil, productive farming and the area
was once an inland sea.
Highlands: include the Superior Highlands and the Ozark Plateau (the Ozark
Plateau has several caves that were formed by eroding limestone).
Canadian Shield
Stretches from the Arctic Ocean to the Great Lakes, and covers the eastern
half of Canada and parts of the northeastern United States.
Glaciers eroded its mountains.
Soil in the Canadian Shield is poor, unsuitable for farming, but rich
in minerals.
Appalachian Highlands
Three areas make up the Appalachian Highlands: the Appalachian Plateau,
the Great Valley, and the Appalachian Mountains.
Extends from Canada to Alabama.
Coastal Plains
East of the Appalachian Highlands is the Coastal Plains stretching from
Massachusetts to Mexico.
Atlantic Coastal Plain: Massachusetts to Florida. In the north it has
an irregular coastline with many natural harbors, eg. Chesapeake Bay; in
the south it has lagoons and swamps like the Everglades.
Gulf Coastal Plain: along the Gulf of Mexico, huge delta in Louisiana
where the Mississippi River empties into the gulf, and has many bayous.
Climates of North America
Tropical Moist
Hot all year and has a lot of precipitation.
Areas that have a tropical moist climate are the tropical rain forest,
the savanna, and the tropical monsoon.
Tropical rain forest: in Hawaii, Mount Waialeale on Kauai, is one of the
wettest spots on earth.
Dry
Little precipitation and temperatures vary.
Desert: yearly temperature range is great, this climate is found in the
southwestern part of the United States.
Steppe: more precipitation than deserts, the climate of the Great Plains
is a steppe climate.
Moist Mild Winter
Humid Subtropical: hot summers and mild winters, eg. southeastern United
States (Florida).
Mid-latitude Marine: damp and wet, eg. Pacific Coast. The growing season
of the Pacific Coast is longer than other regions because the warm winds
from the Pacific Ocean affects the temperature.
Subtropical Monsoon: lower temperatures in winter, eg. Mexico and Central
America.
Mediterranean: long summers, short, mild winters, eg. California.
Moist Severe Winter
Moist, severe winter climates are found in the middle and high latitudes
of the Northern Hemisphere, mostly in the interior parts of continents.
Humid Continental: have hot summers, eg. Midwest and Great Plains.
Humid Continental with warm summers, eg. southern Canada and the north
central and northeastern United States.
Subarctic: no fall or spring, very low temperatures, eg. northern Canada
and Alaska.
Polar
No summers and is the opposite of tropical climates.
Tundras: no month is free of frost, eg. northern Canada and northern Alaska.
Icecap: temperatures are never above freezing, plants do not grow, eg.
central and northern Greenland.
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