Home-School Connection · 2019-03-28 · ¿Sabían que un arrecife de coral es algo que tiene vida?...
Transcript of Home-School Connection · 2019-03-28 · ¿Sabían que un arrecife de coral es algo que tiene vida?...
Home-School ConnectionHome-School Connection
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Name
Word WorkoutWORDS TO KNOW
brittle current eventually
reef suburbs partnership
Silly Stories Let’s make up a silly story with the words. For example, we could tell of a coral reef gobbling up a town.
SPELLING WORDS
grocer singer zipper harbor grader
enter powder elevator polar odor
danger tanker collar daughter popular
victor pepper anchor cheddar barber
er, ar, or or? All the spelling words this week have the same ending sound, but the sounds are spelled differently. I’ll write the spelling words, leaving off the last two letters of each word. You can write in the correct ending. We’ll go over your words together.
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Dear Family Member:Did you know that a coral reef is a living thing?
It is made up of millions of tiny animals called coral polyps. We’re reading about the coral reef this week in At Home in the Coral Reef. I’m reading about all the animals and plants that live in this environment. As I read, I’ll be able to compare the coral reef with other sea environments. I’ll learn how they are alike and different.
This Week’s Skills
Comprehension: compare and contrast
Vocabulary: context clues —multiple-meaning words
Spelling/Phonics: pronouncing er, ar, and or at the end of words
You, the Illustrator Try your hand at illustrating. Choose two different animals or plants. Draw them as best you can. If you are able, add labels. Show your illustrations to a family member. Tell how they are different and alike.
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Conexión con el hogarConexión con el hogar
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Queridos familiares:¿Sabían que un arrecife de coral es algo que
tiene vida? Está formado por millones de animalitos pequeños llamados pólipos de coral. Esta semana estamos leyendo sobre los arrecifes de coral en un libro llamado At Home in the Coral Reef. Estoy leyendo sobre todas las plantas y animales que viven en este medio ambiente. A medida que lea podré comparar el arrecife de coral con otros ambientes marinos. Aprenderé en qué se parecen y cómo se diferencian.
Destrezas de la semanaComprensión: comparar y contrastar
Vocabulario: claves de contexto —palabras con varios signifi cados
Ortografía/Fonética: la pronunciación de er, ar y or al fi nal de palabra
Nombre
Ejercicio de palabrasPALABRAS DE VOCABULARIO
brittle current eventually
reef suburbs partnership
Cuento fantástico Vamos a inventar un cuento fantástico con las palabras. Podríamos hablar sobre un arrecife de coral que se traga un pueblo entero.
PALABRAS DE ORTOGRAFÍA
grocer singer zipper harbor grader
enter powder elevator polar odor
danger tanker collar daughter popular
victor pepper anchor cheddar barber
¿Cómo terminan? Aunque todas las palabras de ortografía de esta semana tienen el mismo sonido fi nal, ese sonido no se escribe igual. Voy a escribir todas las palabras de la lista, pero sin las últimas dos letras. Tú debes escribir la terminación apropiada. Revisaremos las palabras juntos.
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Tú, ilustrador¿Tienes mano para el dibujo? Intenta hacer de ilustrador. Escoge dos animales o plantas diferentes. Dibújalos lo mejor que puedas. Si quieres, agrega rótulos a las ilustraciones. Muéstraselas a un familiar. Dile en qué se parecen y en qué se diferencian.
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AlikeDifferentSummarize
Use a Venn diagram to help
you compare and contrast
two of the natural forces that
change Earth’s surfaces. Then
use the completed diagram to help you summarize
the book.
Think and Compare 1. Turn to pages 10-11 of this book. How are
tsunami waves like other waves? How are they
different? (Compare and Contrast)
2. What kinds of changes to Earth’s surface have
you seen? What do you think caused them?
(Apply)
3. Scientists from all over the world continue to
explore changes to the surface of Earth. What
do they hope to learn? How will their research
help us? (Evaluate/Synthesize)
Comprehension Check
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Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Chapter 1Shifts in the Land. . . . . . . . . . . . . . . . . . . . . . . . 4
Chapter 2Changes Due to Water . . . . . . . . . . . . . . . . . . . 9
Chapter 3Changes Due to Weather. . . . . . . . . . . . . . . . 13
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Glossary/Index . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Comprehension Check . . . . . . . . . . . . . . . . . . . 20
by Barbara M. Linde
Changing Changing Earth Earth
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IntroductionHave you ever seen photographs of Earth
taken from outer space? Earth looks about
the same in all of them. It’s always round.
You always see land and water. From far
away, you’d think that Earth does not change
very much. But that is not true.
In fact, Earth is always changing. Waves
and weather change Earth’s surface. The
land moves and causes changes. Old
features disappear, and new features form.
Earthquakes, volcanoes, and hurricanes are
natural disasters. They change Earth’s surface.
In this book you’ll find out more about the
forces that change the surface of Earth. You’ll
learn how these changes affect Earth.
Earthquakes, landslides, and volcanoes
change the surface of Earth.
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deposition (dep-uh-ZIH-shuhn) the addition of
material to a landform (page 8)
earthquake (URTH-kwayk) the movement of one or
more of Earth’s plates (page 4)
erosion (i-ROH-zhuhn) a wearing or washing away
over time (page 6)
glacier (GLAY-shuhr) a large body of ice formed by
built-up ice and snow (page 6)
hurricane (HUR-i-kayn) a storm with strong winds,
thunderstorms, and rain (page 15)
tornado (tawr-NAY-doh) a spinning, funnel-shaped
column of wind (page 15)
volcano (vol-KAY-noh) an opening in Earth through
which gases and molten rock erupt (page 5)
Indexcoral, 8
current, 10, 12
delta, 12
deposition, 8, 18
dunes, 16
earthquake, 2, 4, 7, 11
erosion, 6, 7, 16, 18
Florida, 8, 10, 12–15,
glacier, 6
hurricane, 2, 14–15
landslide, 3, 7
rivers, 4, 12
tornado, 14–15
volcano, 2, 5, 7
water cycle, 9
weathering, 17–18
winds, 8, 11, 13, 15–16
Glossary
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ConclusionThe surface of Earth changes all the time.
Waves, weather, and movement shape the
land. Weathering, erosion, and deposition
cause changes. Natural disasters change the
shape of Earth, too. Changes go on every
day. Changes will continue in the future.
Scientists learn more about these changes
all the time. Today they understand the
processes better. They have learned more
about the effects of the changes on the
surface of Earth. You can learn more about
our changing Earth, too. Watch the waves on
a beach. Look at a hillside near your home.
Read more books and magazines about our
fascinating, ever-changing Earth!
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C H A P T E R 1
Shifts in the LandEarth’s crust and upper mantle are made
up of large, thin, stiff plates. These plates
border each other. Sometimes one of the
plates shifts and moves against another
plate. This movement causes an earthquake.
Scientists know there are around 20,000
earthquakes every year.
Earthquakes cause changes in the surface
of Earth. Over millions of years, some plates
crashed into each other. The force of the
crashes made parts of the crust rise or fall.
The rising and falling crust formed mountain
ranges. Small or large cracks may suddenly
open up in the ground. The course of a river
can change quickly. Blocks of soil can rush
downward or sideways. Soil under the ground
moves and makes openings on Earth’s surface.
Earthquakes create
cracks called faults.
The San Andreas Fault
is in California. You
can see 625 miles of
the fault on the land.
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WeatheringWeathering is the breaking up of rock,
wood, soil, and minerals from contact with the
atmosphere. The materials break up or loosen,
but they stay in place. Physical weathering
is a slow process. It is caused by changes
in temperature. Water and ice also cause
physical weathering. Rain may get into cracks
in a rock. The rain might freeze and form ice.
Then the ice expands. The pressure of the ice
may crack the rock even more.
Rocks are made up of different kinds of
minerals. Water and chemicals in the air can
change some of the minerals in the rocks.
Sometimes the rocks change color. Other
times the rocks may slowly break up. This
slow process is called chemical weathering.
Rainwater made the lava very brittle. As a result,
the lava cracks easily.
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WindsWind causes erosion by blowing away the
top layers of soil. The wind deposits this
material in other areas, changing some of
Earth’s features.
Sometimes particles of sand and dust in
the wind rub against the surface of rocks.
Over long periods of time, the particles wear
away parts of the rock.
The rocks change into
amazing new shapes.
Strong winds move sand
across beaches and create
huge hills. These hills are
called dunes. Small plants
grow in the dunes. The
plants’ roots hold the sand
in place. Sometimes high
waves drag some of the
sand back onto the beach.
Dunes act as a barrier between the ocean and the
land. They keep the land behind them from eroding.
Wind erosion
created Delicate
Arch and other
arches in Arches
National Park, Utah.
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VolcanoesHot molten, or semi-liquid, rocks and gases
build up underground over a long period.
Then suddenly they erupt, or break through
Earth’s crust. The opening where the eruption
takes place is called a volcano. The molten
rock, called lava, flows out of the volcano.
Lava destroys things in its path. Eventually
the lava cools off and hardens. It sometimes
forms a mountain around the volcano. Or the
lava flows outward and forms new land.
Mount St. Helens Mount St. Helens is an active volcano. On
May 18, 1980, it erupted for nine hours. The
eruption blew off one side of the mountain.
The blast blew down whole forests. Ash and
rock buried other forests. Hot ash and gases
melted some of the snow on the mountain.
The melted snow caused mudflows.
Mount St. Helens before 1980
Mount St. Helens erupting in 1980
Mount St. Helens in 2006
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GlaciersA glacier is a large body of ice. It forms
when snow and ice build up from year to
year. Some glaciers are thousands of years
old. One kind of glacier forms in mountain
valleys. The huge ice sheets that cover
Antarctica and the North Pole are also
glaciers.
Glaciers move downward as they grow.
They often carry parts of mountains, loose
rock, and other materials with them. This
movement of materials is called erosion.
Melting glaciers leave behind piles of rock.
They also leave large holes in the ground.
The holes fill with melted ice and form lakes.
The land surface in Antarctica is covered by an
ice sheet. Parts of the sheet are 2.6 miles (4,200
meters) thick. The ice sheet formed over 40 million
years ago.
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Hurricanes and TornadoesA hurricane is a warm-water storm. It has
strong winds, heavy rain, and thunderstorms.
Hurricane season lasts from June through
November. The winds destroy plants and alter
the shape of beaches. Rain may cause floods.
A tornado is a spinning, funnel-shaped
column of wind. It travels across the surface
of the land or sea. Tornadoes damage or
destroy buildings and plants. Most places
have two tornado seasons. One is from June
to September. The other is from February
to April. The worst tornadoes usually occur
between February and April.
Tornadoes occur during some thunderstorms.
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The effects of weather change Earth’s
surface. Heavy rains and melting snow cause
flooding. Winds blow sand and dirt around.
Dry weather may cause large cracks in the
ground. Dry weather also loosens the soil.
Wind can blow away the loose soil.
Hurricanes in 2004 The year 2004 was the worst on record for
hurricanes. There were six big hurricanes. All
of the storms caused flooding. Plants and
buildings suffered a lot of damage.
Hurricane Ivan destroyed many homes.
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Landslides A landslide is the flow of rocks or soil
down a slope. Hills and mountains are two
kinds of slopes. A landslide usually occurs in
a kind of partnership. First, there’s a volcano,
earthquake, wildfire, or flood. This event
weakens the slope. Then gravity makes the
rock and soil move downward. Erosion from
the landslide changes the surface of the
slope. The landslide may also damage other
things in its path.
Cities and suburbs are often built too close
to slopes. Landslides may damage them.
Buildings on hillsides may weaken the land.
Then an earthquake, heavy rain, or snow
could start a landslide.
Landslides occur all over the world. They can
happen on any slope. A landslide usually starts
slowly but quickly gains speed and size.
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DepositionDeposition takes place when material is
added to a landform. Wind, water, and ice
can all cause deposition.
The Florida Keys were formed by
deposition. Long ago, forests of tiny creatures
called coral grew in the ocean off the coast
of Florida. The coral built up to form a large
underwater reef, or ridge. Over time, the level
of water in the ocean dropped. The coral
died. Sand and other things built up on the
reef. The water level rose and fell a few more
times. Finally, parts of the reef were again
above water. The Florida Keys are the tops of
the reef.
There are about 800 islands in the Florida Keys.
The Keys are just over 100 miles long. Most of the
land is only a few feet above sea level.
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C H A P T E R 3
Changes Due to Weather Weather occurs close to the surface of
Earth. Weather includes temperature, air
pressure, and humidity. Wind, clouds, and
sunshine are weather, too. Precipitation is part
of weather. Thunderstorms, lightning, and dust
storms are also weather.
Every place on Earth has weather. Some
places, like western Australia, have the same
weather for months. In other places the
weather may change quickly. One day can be
sunny and hot. The next day might be cloudy
and cool.
People enjoy sunny, warm days.
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Rivers A river is a body of water that flows from
one place to another. Gravity makes rivers
flow downward. They go from a high place
into a lake, another river, or the ocean. Rivers
erode the land upstream. The current carries
mud and other material downstream. Then
deposition forms new features along the path
of the river.
A river current carries material downstream.
The current slows down at the mouth of
the river. This is where the river flows into
another body of water. The river deposits
material at its mouth. The land that is formed
in the mouth of the river is called a delta. It’s
shaped like a triangle.
The Apalachicola River Delta is in Florida. It forms
in the Gulf of Mexico.
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Evaporation
Condensation
Runoff
Precipitation
C H A P T E R 2
Changes Due to WaterThree-quarters of Earth’s surface is covered
with water. Water makes many changes to the
land. The water cycle replaces Earth’s water.
The water cycle
is the movement
of water above,
on, and below the
surface of Earth.
Temperature, air
pressure, and
landforms all
affect the water
cycle. Most of the
water on Earth is
in the ocean. Heat
from the sun warms the water. Some water
evaporates, or changes into a gas called water
vapor. The water vapor rises into the colder
air where it changes back into a liquid. Drops
of water join together and form clouds. Some
clouds get too full of water. The water falls
to Earth as precipitation. Rain, snow, sleet,
and hail are all forms of precipitation. Most
precipitation falls into the ocean.
The same water is recycled
all the time. Drops of water
in the cycle may be millions
of years old.
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Waves A wave is the rise and fall of the water’s
surface. When waves move into shallow water,
they get taller. Their speed slows down until
they break on the shore. The waves bring
sand from the deeper ocean onto the shore.
They deposit some of the sand on the beach.
Then they wash over it and take away small
particles. Currents near the shore carry sand
along the ocean floor near the beach. The
currents deposit the sand. It builds up and
forms sandbars. Strong waves also break up
rocks on the beach. Over time, the rocks
wear down and become small bits. The
shoreline is always changing because of the
constant motion of ocean waves.
Protecting beaches is very important. Workers
add new sand to the beaches. City and state laws
protect beaches from too much use.
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TsunamisA tsunami is a series of huge waves.
The wind does not cause a tsunami. An
underground earthquake or a volcanic
eruption causes a tsunami. Most tsunamis
occur in the Pacific Ocean. As the tsunami
travels through the ocean, it gains strength
and speed. The tsunami pushes huge
amounts of water onto the shore. The force
of the water changes the shape of the
beach. It destroys things in its path. The
water floods the land.
A tsunami formed in the Indian Ocean in
2004. Indonesia and 10 other countries had
floods and other damage. This was the worst
tsunami in history.
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