3 6 weather and storms (earth science)

a lot of traffi c on a warm day in a large city, what kind of warning do you think it would be likely for a weather reporter to give.. Vocabulary atmosphere blizzard hurricane tornado we

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Scott Foresman Science 3.6

Nonfi ction Make Inferences • Captions

• Diagram

• Labels

• Glossary

Weather

ISBN 0-328-13824-X

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+^-Ä-U-Ä-Scott Foresman Science 3.6

Nonfi ction Make Inferences • Captions

• Diagram

• Labels

• Glossary

Weather

ISBN 0-328-13824-X

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+^-Ä-U-Ä-1 What are two qualities of air that

help people describe the weather?

2 What does a barometer measure?

3 How do satellites help us predict

the weather?

read about why it snows so much

in New York State Using words from the book, write to explain why New York State gets so much snow

a lot of traffi c on a warm day in

a large city, what kind of warning

do you think it would be likely for

a weather reporter to give?

What did you learn?

Vocabulary

atmosphere

blizzard

hurricane

tornado

weather

Picture Credits

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The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions.

Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd).

Opener: Digital Vision; 3 (TR) Getty Images; 5 Jim Reed/Corbis; 6 Getty Images; 7 Getty Images;

9 (TL) Getty Images, (BR) Digital Vision; 10 Getty Images; 11 Getty Images; 12 Corbis; 13 Getty Images;

14 (BL, BR) Getty Images; 15 (BL) Digital Vision, (BR) Brand X Pictures.

Scott Foresman/Dorling Kindersley would also like to thank: 4 (BR) Stephen Oliver/DK Images.

ISBN: 0-328-13824-X

This publication is protected by Copyright, and permission should be obtained from the publisher prior to any

prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic,

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Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025.

3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05

by Lisa Oram

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All About Weather

Some people love rainy days Other people

prefer hot, sunny days When we talk about

rain, sun, and temperature, we are talking about

weather The weather affects us every day

If you don’t like the weather one day, just

wait Weather always changes Different parts

of each country usually have different kinds

of weather Everywhere you go in the world,

the weather is different

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The Atmosphere

Water vapor in the atmosphere helps cause

weather The atmosphere

is made of air that surrounds the Earth

This air is made of gases

To understand the weather, we study the air in the atmosphere

Information about the air’s moisture, speed, and temperature can tell us about the weather

The atmosphere presses down with a force called air pressure When the air pressure changes, the weather often changes too

Low air pressure often means the weather will

be cloudy or rainy High air pressure often makes dry, clear weather

Thunder clouds Thin clouds Scattered clouds

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Scientists study the weather by using special

instruments Barometers measure air pressure

Anemometers measure wind speed Hygrometers

measure water vapor in the air These instruments

help predict weather changes

Warm, wet air has humidity This can

often make the weather rainy Scientists use

a hygrometer to measure humidity They can also

use a rain gauge while it’s raining to fi gure out

the amount of rainfall

Studying the Weather

Barometer

Anemometer

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Hygrometers, barometers, anemometers, and rain gauges are all important instruments

They provide information that is used to predict and record the weather

Satellites tell what is happening with the weather Satellites orbiting in space take pictures of the air

as it moves over the Earth Those pictures are sent back to Earth The pictures are used to make

weather maps Weather maps show what kind of air is moving over the oceans and land They tell

us what kind of weather we’ll get!

Scientists study weather maps, which use information

from satellites.

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Satellite pictures also help scientists track the pollution

Pollution can harm the Earth and change our weather

Factories, cars, and airplanes cause pollution

They produce harmful gases The gases get trapped

in Earth’s atmosphere

These gases can get heated

by the Sun This changes the gases into smog and ozone These are forms

of air pollution

Pollution and the Weather

Smoke from factory chimneys harms the atmosphere.

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Factories, cars, and trucks create smog

The smog pollutes the air over towns and cities

Too much smog makes it hard for people to breathe outdoors When smog levels become harmful, weather reporters might issue a smog alert

You can help to reduce air pollution by cutting down on car trips You could also get rides in the cars of your friends Using public transportation also reduces air pollution

Cars produce gases that pollute our towns and cities.

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Weather patterns are caused by many things

The Sun, oceans, and mountains all affect weather

patterns Some places get the same weather

patterns again and again One very typical weather

pattern involves snowfall in New York State

Let’s take a look at how it works

During the winter, New York State can get

very cold The air can’t carry much moisture

when it is cold So why does it snow so much in

New York State? New York is bordered by two

of the Great Lakes, Lake Ontario and Lake Erie

The other Great Lakes are Lakes Huron, Michigan,

and Superior Lots of water evaporates from the

Great Lakes, even in winter Air moving in from

the west absorbs the evaporated water The air

absorbs so much water that it can’t hold it all

By the time the air is ready to release the water,

it has moved east, over New York State So the

air releases the water, which falls as snow during

the winter That’s why it snows so much in the

areas of New York State that are closest to the

Great Lakes

Patterns of Weather

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CANADA

Lake Huron

UNITED STATES

Lake Michigan

Water evaporates from the Great Lakes and is carried eastward by the wind.

In winter, water from the Great Lakes falls as snow over much of western and central New York State.

Lake Ontario

New York City

Lake Superior

Lake Erie

ATLANTIC OCEAN

wat e r vap

o r trav e

ls ea st

wa r d

NEW YORK STATE

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Hurricanes are large storms that form over the ocean

Stormy Weather

Hurricanes, tornadoes, thunderstorms, and

blizzards are dangerous storms

Hurricanes

A hurricane is a big storm It forms over the

warmest parts of oceans Heat from the warm water

helps cause this storm The center of a hurricane

is called the eye Strong winds swirl around the

hurricane’s eye

Hurricanes can cause a lot of damage The heavy

rain often causes fl ooding Hurricane winds can

blow up to 155 miles per hour These winds can

blow over buildings, power lines, and trees If you

know a hurricane is coming to your area,

stay indoors

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A tornado is also

a dangerous storm It is different from a hurricane

A tornado forms quickly and moves fast over a small area of land Tornado winds can reach 250 miles per hour

Tornado winds are much stronger than hurricane winds, but they don’t affect as large an area

Tornadoes are sometimes called twisters because they look like spinning towers of air People say

a tornado sounds like an airplane taking off or a train roaring down its track

Tornadoes

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Storms that cause rain, thunder, and lightning

are called thunderstorms Thunderstorms, which

usually last for short periods of time, can also

cause high winds and hail

Hail is water that freezes inside large storm

clouds The hailstones become heavy and fall

to the ground as chunks of ice Hail can happen

even if it is warm

A blizzard is a dangerous winter storm

During a blizzard, temperatures drop and heavy

snow falls Strong winds blow the snow into

drifts Because of the wind and the snow, it is

hard to see well People should not drive during a

blizzard It is easy to have an accident or get lost

Thunderstorms and Blizzards

Snowdrifts almost buried these cabins during a blizzard.

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Storms can be dangerous People need to know how to stay safe during them

How do people know if a dangerous storm

is coming? The National Weather Service staff monitors the weather They send announcements

to radio and TV stations If there is a storm watch,

it means a storm could happen in your area If there is a storm warning, it means a storm is on its way When people know that a storm is coming, they can get prepared

Staying Safe During Storms

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The seasons affect weather patterns

The weather in some seasons helps living

things to grow The weather in other seasons

can hurt living things There are many different

kinds of weather, each with its own causes

and effects

The Weather and You

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At fi rst you might have thought that there was little you could do about the weather

Now you know differently! By watching for National Weather Service reports, you can prepare for dangerous weather By cutting down

on car trips, you can help prevent air pollution

You can make a difference to the weather!

Winter Fall

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atmosphere the air that surrounds the Earth

temperatures and heavy, blowing snow

hurricane a tropical storm that forms over

the ocean and causes strong winds and heavy rainfall

tornado a spinning column of air that has

high wind speeds and sometimes touches the ground

weather what it is like outside

Glossary

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1 What are two qualities of air that