What causes the day to be longer in the summer in the northern hemisphere?. The half of Earth tilting toward the Sun is warmer than the half that is tilting away.. The northern half of E
Trang 1Suggested levels for Guided Reading, DRA, ™
Lexile, ® and Reading Recovery ™ are provided
in the Pearson Scott Foresman Leveling Guide.
Expository
nonfi ction
• Cause and Effect
• Compare and Contrast
• Ask Questions
• Diagrams
• Captions
• Labels
• Glossary
Scott Foresman Reading Street 4.3.1
ISBN 0-328-13442-2 ì<(sk$m)=bdeech< +^-Ä-U-Ä-U
Sen
Seasons
by Ben Scott
Earth Science
Suggested levels for Guided Reading, DRA, ™
Lexile, ® and Reading Recovery ™ are provided
in the Pearson Scott Foresman Leveling Guide.
Expository
nonfi ction
• Cause and Effect
• Compare and Contrast
• Ask Questions
• Diagrams
• Captions
• Labels
• Glossary
Scott Foresman Reading Street 4.3.1
ISBN 0-328-13442-2 ì<(sk$m)=bdeech< +^-Ä-U-Ä-U
Sen
Seasons
by Ben Scott
Earth Science
Trang 21 Reread page 6 What causes the day to be longer
in the summer in the northern hemisphere? What
is an effect of the summer season? Write your responses in a chart similar to the one below.
2 Reread page 10 If you could interview Aldo
Leopold, what questions would you ask him?
Where could you go to find more information about plant growth during certain seasons?
3 Use the Glossary and a dictionary to find three
meanings of draft Use each meaning in a
sentence.
4 How does the diagram on pages 4 and 5 help you
understand how the Earth moves?
Reader Response
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Sensational
Seasons
by Ben Scott
13442_001-016.indd Sec1:1 11/16/05 4:10:12 PM
Trang 3Every effort has been made to secure permission and provide appropriate credit for
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ISBN: 0-328-13442-2
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2 3 4 5 6 7 8 9 10 V0G1 14 13 12 11 10 09 08 07 06 05
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3
Seasons Change and Have Patterns
The first humans on Earth must have been
fascinated by wildflowers in spring The more timid people might have hidden in terror from
the summer sun They were probably happy to
see colored leaves in fall and designs etched by the winter frost Why do the seasons change and
have patterns?
Winter Spring
Fall Summer
13442_001-016.indd Sec1:3 11/16/05 4:10:24 PM
Trang 4Our Wonderful World
Suppose that Earth is a toy top spinning in
slow motion You, the spinner of the top, are the
Sun One full turn of the top equals one day The
side facing you is in daylight It is night on the
other side
Earth
Axis
The direction the Earth travels around the Sun
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5
Earth spins on its axis The axis is an imaginary line through the center of Earth Earth spins on its axis as it travels around the Sun Each spin takes one day Each trip around the Sun takes one year
Earth tilts on its axis as it spins The half of Earth tilting toward the Sun is warmer than the half that is tilting away The tilt of Earth as it travels around the Sun gives us our seasons
Sun
13442_001-016.indd Sec1:5 11/16/05 4:10:41 PM
Trang 5The Seasons
There are twelve hours of daylight and twelve
hours of darkness on the first day of spring The
Sun is directly over the equator on this day
Then daylight hours get longer The northern
half of Earth, called the northern hemisphere,
tilts toward the Sun The first day of summer has
the most sunlight of the year The weather is
warmer because the Sun’s rays hit the northern
hemisphere more directly
First Day of Summer June 21
How the seasons change
as Earth circles the Sun
First Day of Spring March 21
Sun over Equator
Equator
Equator
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7
Then Earth’s axis starts to tilt away from the Sun Rays of sunlight reach the northern hemisphere less directly The weather cools
There is less daylight
The Sun is also over the equator on the first day of fall Equal amounts of Sun reach the northern and southern hemispheres The northern hemisphere keeps tilting farther away from the Sun The first day of winter is the shortest day of the year in the northern hemisphere
The northern hemisphere tilts toward the Sun in the summer
It tilts away in the winter.
First Day of Winter December 22
First Day of Fall September 23 Sun over Equator
Equator
Equator
13442_001-016.indd Sec1:7 11/16/05 4:10:49 PM
Trang 6Sing for Springtime
There are also many signs on the ground that
a new season has begun For example, birds sing
more in the spring Male birds sing to warn other
birds to stay away from their areas This way they
can safely find food The birds raise their families
A starling sings.
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9
The amount of sunlight during the day affects most plants
Sunlight tells plants when to start making leaves or flowers
For example, the wood anemone reacts to short days It grows flowers in early spring
Wood anemone
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Trang 7The Days of Summer
Summer is a time of growth in the natural
world Naturalist Aldo Leopold studied living
things He counted many species of plants that
bloomed during July and August on his farm in
Wisconsin Plant growth helps birds and other
animals find food
Wildflowers in a meadow
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11
Birds and other animals begin to molt in early summer This means that they begin to lose their feathers or fur They grow new coats for the winter Animals may also gain weight They store fat to help them get through the cold season
Molting feathers
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Trang 8Frost Comes in the Fall
Deciduous trees lose their leaves in the fall
The trees draw back food from the leaves The
leaves turn brown, red, and yellow Then they
fall off
Evergreen trees have needles instead of
leaves They lose a few needles in the fall Most
of the needles stay on the trees all year long
Evergreens only lose
a few needles These trees stay green throughout the year
Many trees
lose their
leaves in
the fall.
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13
Some birds fly south in the fall They will spend the winter where it’s warmer Birds are not the only animals that migrate when the days get colder Many monarch butterflies fly more than two thousand miles south to Mexico
Monarch butterflies migrate south for the winter.
13442_001-016.indd Sec1:13 11/16/05 4:11:20 PM
Trang 9Winter Wonderland
Many wild animals survive the drafts of winter
by going to sleep Hedgehogs, bats, and some
mice are hibernators Their body temperatures
fall Their breathing and heartbeat rates become
much slower These animals live off their stored
body fat in the winter
A squirrel’s nest of
leaves and twigs
keeps the squirrel
from freezing in
the winter.
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15
Most animals do not have a market for food
They don’t have a cozy parlor to help them keep
warm in the winter Animals are adapted to the cold Soon the cold winter days will pass and spring will come again Then the hibernating animals will wake up Another cycle of seasons will begin as Earth circles the Sun
Animals such as frogs, snakes, and turtles may also sleep through the winter
13442_001-016.indd Sec1:15 11/16/05 4:11:34 PM
Trang 10Glossary
drafts n currents of air.
etched v engraved a
drawing or design
fascinated v interested
greatly; attracted very
strongly; charmed.
frost n a freezing
condition; temperature
below the point at
which water freezes.
parlor n a sitting room.
terror n great fear.
timid adj easily
frightened; shy.
13442_001-016.indd Sec1:16 11/16/05 4:11:39 PM
1 Reread page 6 What causes the day to be longer
in the summer in the northern hemisphere? What
is an effect of the summer season? Write your responses in a chart similar to the one below.
2 Reread page 10 If you could interview Aldo
Leopold, what questions would you ask him?
Where could you go to find more information about plant growth during certain seasons?
3 Use the Glossary and a dictionary to find three
meanings of draft Use each meaning in a
sentence.
4 How does the diagram on pages 4 and 5 help you
understand how the Earth moves?
Reader Response