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Our Amazing Earth6 Articles

Check articles you have read:

Volcanoes156 words

Twister!230 words

Wild Weather339 words

Secrets of the Rain Forest201 words

Discover the Rain Forest!280 words

Let's Explore Caves!271 words

Eruption!310 words

Mexico's Natural Wonder: Paricutin Volcano245 words

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Volcanoes

VolcanoesHot Stuff!

Look inside a volcano.

Hot liquid rock moves deep underground. A volcano is ready to erupt, or

explode. Soon, hot liquid rock flows out. That is called lava. Lava can move

slowly or quickly.

Read how a volcano erupts.

Jim Sugar/Corbis

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Volcanoes

(1) Hot liquid rock collects.

Hot liquid rock is found deep underground. It is called magma. (Magma that

flows out of a volcano is called lava.)

(2) The ground shakes.

Magma moves under the volcano. It can cause earthquakes. An

earthquake is a strong, shaking movement of the ground. Rocks break apart

and form cracks in the volcano.

(3) Magma rises.

Magma travels along the cracks deep inside the volcano. Some cracks go

all the way to the outside of the volcano. Those openings are called vents.

(4) The volcano erupts!

Lava comes out the top of the volcano. The top is called the main vent.

Sometimes, gases and smoke burst out too.



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Twister!

Twister!

Pete Turner/Getty Images

Wild Weather

What do you know about tornadoes?

Tornado season has started in the United

States. A tornado is a powerful, spinning wind. It is also known as a twister.

Steve Bloom Images/Alamy

Most tornadoes last fewer than 15 minutes. During

that time, a twister can travel across a large area of

land and destroy everything in its path.

Getty Images

A tornado can destroy homes and trees.

The strong winds

in some

tornadoes reach

speeds of up to

300 miles per

hour. Those

winds can toss

cars and other

objects high into the air.

Tornadoes can happen any time of the

year. However, they are most common

from March through July.



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Twister!

How Does a Tornado Form?Most tornadoes start as thunderstorms. During those storms, heavy rain and

lightning are common. Large hail, or ball-shaped pieces of ice, may also

fall.

Tina Rencelj/Shutterstock

Large thunderstorm clouds appear in the sky. The clouds become dark.

Thunder can be heard.

Jim Reed/Getty Images

Warm and cold air meet. Air rises from the ground to the clouds. If the rising

air starts to spin, a funnel-shaped cloud can form.



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Twister!

Jim Reed/Getty Images

The funnel-shaped cloud spins faster. When the bottom of the cloud

touches the ground, it becomes a tornado.

A.T. Willett/Getty Images

As the tornado travels across the ground, it picks up anything in its way.



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Wild Weather

Wild Weather

fotostock/Superstock

Blizzard

March is filled with many different types of weather. Weather is the

condition of the outside air. Tornadoes are one type of weather. Tornado

winds can reach 300 miles per hour. That's as fast as some airplanes can

fly. Keep reading for answers to some common questions about weather.

The Truth About WeatherThere is a science behind every kind of weather. Uncover some interesting

weather facts.

Why do clouds sometimes look as if they are on the ground instead of

in the sky?

Sometimes clouds form near the ground. That is called fog. Both fog and

clouds are made up of tiny drops of water that hang in the air. Fog forms

over the Golden Gate Bridge in San Francisco, California.



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Wild Weather

What is a blizzard?

A blizzard is a winter storm with strong winds. The wind blows the snow so

that it is hard to see. Most blizzards last at least three hours.

Which comes first, thunder or lightning?

photos.com

Lightning

Thunder and lightning happen at the same time. As lightning strikes, it heats

the air around it. That causes the air to expand. When the air expands, we

hear a loud crash called thunder. The sound reaches us after we have seen

the lightning.

How does rain make a rainbow?

Rainbows appear when sunlight passes through raindrops in the sky. As the

light passes through, it is broken up into seven colors: red, orange, yellow,

green, blue, indigo, and violet.

Cloud Coverage



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Wild Weather

Corel Images

Roy G. Biv is a name made with the first letters of the colors in a rainbow.

Clouds form when warm air rises and then cools.

Cirrus clouds are white, wispy streaks high in the sky. Inside these clouds is

ice.

Cumulonimbus clouds are large thunderclouds. Thunderstorms and

tornadoes can form in these clouds.

Cumulus clouds are large and puffy. They usually form near the ground and

rise to the sky.

Stratus clouds are thick layers of clouds low in the sky. Light rain or snow

can fall from these clouds.



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Secrets of the Rain Forest


Roine Magnusson/Getty Images

David Sheldon

Life in a Tropical Rain Forest

What can you find in this amazing place?

Welcome to a tropical rain forest! It is a warm, rainy place with many tall

trees. More than half of the world's species, or types, of plants and animals

are found here.



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Layers of LifeA tropical rain forest has four layers. From top to bottom, the forest is full of

life.

Ian Cumming/Getty Images

People walk on a bridge through a tropical rain forest canopy.

Trees Clean the AirYou can thank tropical rain forests for

keeping the air clean. Trees help to

recycle Earth's air. The leaves take in a

gas called carbon dioxide. Too much

carbon dioxide in the air is harmful to

people. The leaves then give off a gas

called oxygen. People need oxygen to stay alive.

Marion Brenner/Jupiter Images

Lemon trees grow in tropical rain forests.

Foods and MedicineWhat do lemons, chocolate, and cashew

nuts have in common? They are foods

that first came from tropical rain forests.

Hundreds of foods grow there today.

Many medicines are made from rain forest

plants. Today, scientists are studying the

plants to find new medicines to cure

diseases.



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Discover the Rain Forest!


Many animals live in a tropical rain forest. Some of them have bright colors.

The red-eyed tree frog is one of those animals.

USDA.com

A leaf-cutting ant uses leaves to make a tent for shelter.

What are some others?

What a Colorful Place!

A tropical rain forest is a warm, wet place.

It is a home for many animals. Many kinds

of plants grow there too. Read about the

layers of a rain forest.

The emergent layer is the top layer. It is

made up of the tops of the very tallest

trees. It is home to many birds and insects. Macaws fly up in the trees here.

They like to call loudly to each other. These birds eat fruits, nuts, and

flowers.

The canopy is made up of the tops of most other rain forest trees. It is

home to many animals. Sloths hang upside down from tree branches here.

Big, strong claws on the sloth's feet help it grab a branch. The furry sloth

does not move much.



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U.S. Fish and Wildlife Service

Jaguars live in the understory of the rain forest.

The understory is a dark, cool layer

under the leaves of many trees. Emerald

tree boas wrap around branches of trees

here. The boa hunts at night to catch birds

and other small animals. This snake can

open its jaws wide enough to swallow a

bird whole!

The forest floor is dark and damp. Not

much sunlight reaches it. Leaf-cutter ants

work hard here, using their sharp jaws to cut pieces of leaves. This ant

carries leaves that are 20 times its weight. That is like a person carrying a

1-ton load!



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Let's Explore Caves!


The Cool World of Caves

photos.com

A cave is an empty space inside Earth. Its opening is usually on the side of a hill. Caves are filled with a lot of interesting things. What hangs out in caves?

Caves are home to many different animals. Like any home, a cave suits the

creatures that live in it. Some animals can survive only in a cave's unique

ecosystem. An ecosystem is an environment in which certain plants and

animals depend on each other to live. So, just what lives in caves?

A Blind FindYou might see blind salamanders in caves, but they won't see you! Blind

salamanders do not need sight. They live in the darkest parts of caves-in

water or on land. They are able to catch food by feeling the movements of

other animals.



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Going Up or Down?When water mixes with calcium and drips inside caves, it hardens and

builds up over time. That creates cone-shaped objects called stalactites and

stalagmites. Stalactites hang from the ceiling. Stalagmites rise from the

ground. Sometimes they meet and form columns.

Hanging AroundMany bats sleep in cave doorways. They fly out to find food. Some bats

hibernate in caves during the winter.

sxc.hu

A bat.

Lots of LegsMillipedes like to chill out in the cool, damp middle sections of caves. They

can have anywhere from 80 to 400 legs! Having so many legs helps them

dig their way underground.



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Sneaky Snake

photos.com

A snake.

Rat snakes do not live in caves, but they sure do like to visit! Rat snakes

slither through cave openings to look for food.



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Eruption!

Eruption!

Mexico's "Volcano of Fire" roars back to life. When will the next big explosion occur?

Colima Volcano Observatory

The Colima Volcano

The Colima (koh-LEE-mah) Volcano in Mexico has

roared to life again. The 12,500-foot volcano is

also called the "Volcano of Fire." Over the past few

centuries, it has had several major eruptions.

The Volcano of Fire is Mexico's most

active volcano. It has erupted many times over the

years. What scientists are most worried about is

the next big eruption. The volcano has had huge

eruptions about every hundred years. In the 20

th

century, there was one that took place in 1913.

Leigh Haeger

Scientists study the pattern of activity and compare

it to data taken from the major eruption of 1913.

Volcano experts can use their studies to predict a

time period when there might be a large, explosive

eruption.

Living Near the Volcano



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Eruption!

Leigh Haeger

Inside a volcano.

The volcano is 20

miles north of the city of Colima. To make

sure no one is in danger, officials created

a safety zone around the volcano. People

aren't allowed in that area.

Scientists use special equipment to track

changes within the volcano. "We're

looking for clues of another large,

explosive eruption," says Luhr. "That way, we can be prepared."

How a Volcano Works

Weekly Reader



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Eruption!

Volcanoes are openings called vents on the surface of Earth. Volcanoes

can be active (currently erupting or erupted not long ago), dormant (not

currently active but likely to erupt someday), or extinct (unlikely to erupt

again).

Magma is hot, melted rock beneath the surface of the Earth. When magma

erupts onto the surface of the Earth, it is called lava. Magma collects in

chambers beneath Earth's surface. After pressure from gases in the magma

builds up, the magma erupts out of volcanoes. Volcanoes let out gases,

ash, steam, and lava.



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Mexico's Natural Wonder: Paricutin Volcano


U.S. National Oceanic and Atmospheric Administration

Paricutin Volcano erupting

The Paricutin Volcano in Mexico earned its title as one of the seven natural

wonders of the world in an explosive way.

In 1943, this volcano emerged from a cornfield in a village about 200 miles

west of Mexico City. People living in the area had been feeling the ground

shake and hearing it rumble for weeks. Then one day, the earth in the

cornfield rose up about six feet! Ash and vapor exploded from the ground.

By later that day, a small cone shape had formed. The volcano had begun

erupting, sending lava and pieces of molten rock into the air. As these rock

pieces landed around the new volcano, the cone shape grew bigger and

bigger.

As Paricutin continued erupting, the surrounding area was covered in

smoke and ash. People were forced to leave.

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The eruption was most intense during the first year. By the end of the first

year, the volcano was over 1000 feet high! Within two years, only the top of

a church was visible above all the lava.

Paricutin continued exploding for about nine years before stopping. It is now

about 1,391 feet high!

Now, Paricutin is considered extinct. But during the nine years it was active,

scientists studied the volcano closely. Paricutin is the first volcano that

scientists were able to study and document from birth to death. Thanks to

this natural wonder, scientists learned a lot about volcanoes.

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