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The NorTh americaN continent
is a region of great contrasts. impressive
mountain chains—the appalachians and
rockies—run down its east and west
coasts, enclosing a vast, and mostly flat,
landscape, crisscrossed by mighty rivers
such as the mississippi and missouri. The
north is blanketed with coniferous forests.
The central Great Plains are grasslands, once grazed
by huge herds of buffalo. in the north, the arctic
region is permanently frozen, while in the south,
arid deserts and rocky canyons bake in year-round
sunshine. Tropical forests cover southern mexico, and
in the southeastern US, semitropical wetlands harbor
many endangered species. Native americans are
descendants of the peoples who first settled the
continent over 25,000 years ago. They were
displaced by european colonists
who explored and settled on the
continent from the 16th century.
Successive waves of immigrants,
first from europe, and then from
the rest of the world, settled in
North america, drawn by its
wealth of natural resources, its
fertile prairies, and its vibrant cities—
home to most of its population.Limestone, sandstone, shale,
and granite are eroded at different
speeds, giving the Grand Canyon
its distinctive layered colors.The North american continent
stretches from the arctic circle
to the tropics and is flanked
by the atlantic, Pacific, and
arctic oceans. The five Great
Lakes of North america form
the largest area of freshwater
in the world.rockieS
The rocky mountains form the backbone of the
american continent, separating the great plains
of the east from the high plateaux and basins of
the west. Stretching from the canadian arctic
to New mexico, they are highest in colorado,
where some 254 mountains are over 13,000 ft
(4,000 m). The highest point, mount
elbert, is 14,149 ft (4,312 m).GraNd caNyoN
canyons are dramatic, deep
rock formations created by
the eroding flow of a river.
The most famous is the Grand
canyon in arizona, formed
by the colorado river. it is
220 miles (350 km) long, and
plunges to depths of 5,970 ft (1,820
m). The processes of erosion started
about 5–6 million years ago. Some of
the rocks at the base are 2 billion years
old—the oldest rocks known in the US.faLL iN New eNGLaNd
The climate of North america ranges from
the hot rain forests of the yucatán to the
frozen arctic. The eastern coast of the US has
four distinct seasons. The colors of autumnal
leaves, especially the bright red of the maple,
is a famous sight that attracts many tourists.The biG freeze
Severe winter weather is common
in the center of the continent,
especially around the Great
Lakes, which often freeze over
in the winter. chicago, on Lake
michigan, is prone to severe
snowstorms, which can cut off the
city. in 1998, a freak icestorm in
the canadian Great Lakes region
froze power lines, blacking out
the area for several days.Moose live in the subarctic forests.
They have huge antlers, long legs,
and fleshy muzzles.TUNdra iN aLaSka
Tundra is a finnish word meaning
“treeless heights.” it describes the
landscape of alaska (above), where
the only vegetation is lichens, mosses,
turf, and low-lying shrubs. The average
temperature is below freezing, and in
the winter it can plummet to -89.6°f
(-32°c). These low temperatures leave a
layer of permanently frozen soil which
can reach depths of 5,000 ft (1,525 m).North America 381-
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