Earth Science Textbook Chapter 7 The Atmosphere

Chapter EI Standards Preview 63 Heat moves In I flow from winner objects to cooler until all the objects are at the some temperature . As a basis for understanding this . Students heat Hows by Much involves no How 04 matter ) and by and by ( ol matter ) Students heat energy also between omens by ( can travel through space ) Many phenomena on Earth face ate by the transfer energy through radiation and currents . As a basis In ! understanding this content . Students know solar energy reaches Earth through , mostly the farm of light . Students know ( heat the atmosphere and cream . Students know In pressure . heat . arr movement and resort changes at weather Sources oi and materials in amounts , dis . usefulness . and me time required their formation . As a basis for this can not Students know natural energy and , an , soul , petroleum . fresh water , and forests , and know how to them as renewable or An aurora Illuminate the sky over a in . Canada ,

vim Hula ! and semi The , the . BIG How do air pressure and temperature vary in the atmosphere ?

Check What You Know Suppose you dove into a pool . The deeper you went , the more water there would be above you . The weight of the water above causes the pressure to increase as you go deeper . Like water , air has weight , and pushes on you from all directions . Considering the example above , how do you think the pressure of the air above you would change if you climbed a mountain ?

The images shown here represent some of the key terms in this chapter . You can use this to help you understand the meaning of some key terms in this chapter . Greek Word Origins Many science words come to English from Greek . In this chapter , you will learn the word atmosphere . You learned that means sphere or ball ( see Chapter ) The Greek word atmos means vapor or gas . Therefore , the atmosphere is the layer of gases that surrounds Earth . atmosphere a layer of vapor or gases that surrounds Earth sphere atmos vapor , gas Greek Origin I Meaning I Examples Measure Anemometer , barometer . thermometer light , Thermos Apply It ! Review the Greek origins and meanings in the table . Then predict the meaning of exosphere . Revise your definition as needed . In your notebook , create a table like the one above . After reading Section , add the Greek prefixes and . Then complete the table with meanings and examples . fa atmosphere

Chapter Vocabulary weather atmosphere ozone smog water vapor acid rain Section A density mercury pressure barometer air pressure barometer barometer Section A troposphere temperature stratosphere ionosphere Section , electromagnetic ultraviolet wave radiation radiation Infrared greenhouse electromagnetic wave effect . Section thermal energy thermometer ( heat ( Section land breeze anemometer global wind ( effect latitude local let stream sea breeze . Build Vocabulary 153

Take Notes Science chapters are packed with information . Each section needs to be read at least twice After finding the main idea and important details in a section , take notes so you have something to study . In your notebook create a organizer . Label the side Recall Clues and Questions . Label the right side Notes . Under Notes , write key ideas , using phrases and abbreviations . Include a few important details . Use your notes to write a summary statement for each red heading . Under Recall Clues and Questions , write review and study questions . As you take notes , think about the key concepts and key terms in the section . Look at the example for the first part of Section . Recall ( lues and I Notes The Air Around Von What is What is the atmosphere ?

What is the atmosphere made or ?

Apply It ! What are two important ideas found in the Notes column ?

What questions in the left column help you re ( the content ?

Weather condition of atmosphere Atmosphere gases around Earth Atmosphere made of nitrogen oxygen carbon dioxide ' other gases Statement Earth atmosphere is made up of nitrogen , oxygen , carbon dioxide , water vapor , and many other gases , plus liquids and solids . Take notes as you read each section in this chapter .

St Investigation Gate Build Your Own weather Station in this chapter you will learn about a variety of weather factors such as air pressure , temperature , and wind speed . As you learn about these factors , you will build your own weather station . Your weather station will include simple instruments that you will use to monitor the weather . Your Goal To design and build a weather station to monitor at least three weather factors and to for patterns that can be used to predict the next day weather in completing your investigation , you will develop a plan for measuring weather factors design and build instruments for your weather station use your instruments to collect and record data in a daily log display your data in a set of graphs use your data and graphs to try to predict the weather follow the safety guidelines in Plan It ! Begin your investigation by deciding where your weather station will be located . Plan which instruments you will build and how you will make your measurements . Prepare a log to record your observations Collect and record measurements each day . Graph the data and look for any patterns that you can use to predict the next weather . Compare your predictions with the actual weather conditions the next day . At the end of the chapter , you will present your observations and explain how well you predicted the weather .

Section The Air Around You Standards Focus i Students know in pressure , heat , air movement , and humidity result in changes In weather . Students know different natural energy and material resources . Including ait . soil , rocks . minerals . petroleum . fresh water , and . and know how to classify them as renewable or . What is the composition of atmosphere ?

Now is the atmosphere important to living things ?

What causes smog and acid ram ! Key Terms weather water vapor pollutant photochemical smog acid rain Standards How Long Will the Candle Burn ?

Put on your goggles Stick a small piece of modeling clay onto an aluminum pie pan . Push a short candle into the clay . Carefully light the candle . Hold a small glass jar by the bottom . Lower the mouth of the jar over the candle until the jar rests on the pie pan . As you do this . start a stopwatch or note where the second hand is on a ( lock . Watch the candle carefully . How long does the flame burn ?

Wearing an oven mitt , remove the jar . Relight the candle and then repeat Steps and with a larger jar . Think It Over How would you explain any differences between your results in Steps and ?

The sky is full of thick . dark clouds . In the distance you see a bright . Thirty seconds later , you hear a crack of thunder . You begin to run and reach your home just as the downpour begins . That was close ! From your window you look out to watch the storm , Does the weather where you live change often , or is it fairly constant from day to day ?

Weather is the condition of atmosphere at a particular time and place . But what is the ?

Earth atmosphere ( muh ) is the lope of gases that surrounds the planet . To understand the size of the atmosphere . imagine that Earth is the size of an apple . you breathe on the apple . a thin of water droplets will form on its surface . atmosphere is like that water on the thin layer of gases on Earth surface . from space . Earth atmosphere appears as a thin layer near the horizon .

Gases in Dry Air Other Carbon dioxide Neon Helium Methane Krypton Hydrogen Flour Dry air in the lower Composition of the Atmosphere The atmosphere is made up of a mixture of atoms and molecules of different kinds . An atom is smallest unit of a chemical element that can exist by itself . Molecules are made up of two or more atoms . Earth atmosphere is made up of nitrogen , oxygen . carbon dioxide , water vapor . and many other gases , as well as particles of liquids and solids . Nitrogen As you can see in Figure nitrogen is the most common gas in the atmosphere . It makes up a little more than three fourths of the air we ) Each nitrogen molecule consists of two nitrogen atoms . in a cycle from the air to the soil . into living things , and then back into the air . Oxygen Even though oxygen is the second most gas in the atmosphere . it makes up less than one fourth of the volume . Plants and other organisms use light to convert water and carbon dioxide into oxygen and to produce food . Thus . like . the oxygen in the air moves through a natural cycle involving living things . Oxygen is also involved in many other important processes . Any fuel you can think of , the gasoline in a car to the candles on a birthday . uses oxygen as it burns . oxygen . a will go out . Bunting uses gen rapidly . During other , oxygen is used slowly . For example , reacts slowly with oxygen to form iron oxide . or rust . Most oxygen molecules have two oxygen atoms . Ozone is a form of oxygen that has three oxygen atoms in each molecule instead of the usual two . 79 ! atmosphere generally has about the same 93 composition of ' Interpreting Data was what two gases make up most of the all ?

FIGURE Burning Uses Oxygen Oxygen is necessary in order for the wood to burn . Chapter 257 Water Vapor In the Air There is very little water vapor in the air over the desert where this lizard lives . In the tropical rain forest ( right ) where the frog lives . as mu ( as four percent of the air may be water vapor . I a This Activity Breathe In , Breathe Out How can you detect carbon dioxide in the air you exhale ?

Put on your goggles . Fill a glass or beaker halfway with limewater . Using a straw , slowly blow on through the limewater for about a minute . CAUTION Do not on the straw or drink the . What happens to the ?

Developing Hypotheses What do you think would happen if you did the same experiment after jogging for 10 minutes ?

What would your results tell you about exercise and carbon dioxide ?

Carbon Dioxide Each molecule of carbon dioxide has one alum oi carbon and two atoms of oxygen . Carbon dioxide is essential to life . Plants take in carbon dioxide from the air to make food . When plant and animal cells break down food to produce energy . they give dioxide as a waste product . When fuels such as coal and gasoline are burned . they release carbon dioxide . Burning these fuels increases the amount of carbon dioxide in the atmosphere . Other Gases Oxygen and nitrogen together make up 99 cent of dry air . Argon and carbon dioxide make up most of the other one . The remaining gases are called trace gases because only small amounts of them are present . Water Vapor So far . we have discussed the composition of dry air . in reality . air is not dry because it contains water vapor . Water vapor is water in the form of a gas . Water vapor is . is not the some thing as steam , which is made up droplets of liquid water . Each water molecule contains two atoms of hydrogen and one atom of oxygen . The amount of water vapor in the air varies greatly from place to place and from time to time . Water vapor plays an important role in weather . Clouds form when water vapor condenses out of the air to form tiny droplets of liquid water or crystals of ice . If these droplets or crystals become heavy enough , they can all as rain or snow . Particles Pure air contains only gases . But pure air exists only in laboratories . The air we breathe also contains tiny solid and liquid particles of dust . smoke . salt . and other chemicals . You can see some of these particles in the air around you , but most are too small to see . What is water vapor !

Importance of the Atmosphere Earth atmosphere makes conditions on Earth suitable for living things . The contains oxygen and other gases that living things need to survive . Living things also need warmth and liquid water . By trapping energy from the sun . the keeps most of Earth surface warm enough for water to exist as a liquid . In addition . Earth atmosphere living things from ultraviolet radiation from the sun . The atmosphere also prevents Earth surface from being hit by most meteoroids . which are rocks from outer space . The atmosphere is constantly changing . with gases such as nitrogen . oxygen . and carbon dioxide moving in and out of living things . the land . and the water . Front this point of view . air can be considered a renewable resource . Air Quality Breathing brings air into your lungs , where the oxygen you need is taken into your body . But not everything in the air is , may also breathe in tiny particles or even a small amount of harmful gases . If you live in a large city , you may have noticed a brown haze in the air . Even if you live far from a city . the air around you may contain . are harmful substances in the air , water . or soil . Air that contains harmful particles and gases is said to be polluted . Air pollution can affect the health of humans and other living things . Sources of Pollution Some pollution occurs naturally . For example . many natural processes add particles In the sphere . Forest fires . soil erosion . and dust storms release a great deal of smoke and dust into the air . The wind carries particles of and pollen . Erupting spew out ol dust and ash along with poisonous gases . I Go For Links on the ( Web Code 17141911 Chapter 259

. For More on air pollution Web ( ode hour I Results of Arid Rain This scientist is studying trees damaged by acid rain . Needle leafed trees such as pines and are especially sensitive to acid rain . Add may make tree needles tum brown or fall off . 260 Most air pollution is the result of burning fossil fuels , such as coal . oil . gasoline . and fuel . Almost half of this tion comes from cars and other motor . Factories and power plants that burn coal and oil also pollution . Burning fossil produces il variety of pollutants . including carbon . nitrogen . and sulfur oxides . Smog and Acid Rain High of air pollution decrease the quality of the air . The burning of fossil fuels can cause smog and acid rain . One hundred years ago . the city . England . was dark and dirty , Factories bumed coal , and most houses were heated by coal . The air was full of soot . In . the term smog was created by combining the words and log to describe this type of air pollution . Fortunately . smog is no longer common . Instead . many cities today have another type of smog . The haze that develops in sunny cities is called photochemical smog ( toh ' ih ) The in Photochemical smog is formed by the action of sunlight on pollutants such as hydrocarbons and nitrogen oxides . These chemicals react to a brownish mixture of omne and other pollutants Smog can irritate the ' throat . and lungs . It can also harm plants and other living things . Another result of air pollution is acid rain . Rain is naturally slightly acidic . but rain that contains more acid than normal is known as acid rain . How does acid rain form ?

The burning of coal that contains a lot of sulfur produces sulfur oxides , stances composed of oxygen and sulfur . Acid rain forms when nitrogen oxides and sulfur oxides combine with water in the air to form nitric acid and sulfuric acid . Acid rain is sometimes strong enough to damage the faces of buildings and status . It also harms lakes and ponds . Acid rain can make so acidic that many plants and animals Can no longer live in it .

Reviewing Key Concepts INT Improving Air Quality In the United States , the federal and state governments have passed number of laws and regulations to air pollution , The Environmental Protection Agency ( EPA ) monitors air pollutants in the United States . Air quality in this country has generally improved over the past 30 years The of most major air pollutants have . Many cars cause less pollution than older models . power plants are less polluting than power plants that have been in operation for many . there are now more cars on the road and more power plants burning fossil fuels than in the past . Unfortunately . the air in many American cities is still polluted . Voluntary measures . such as greater use of public transportation in place of driving . could the total amount of air pollution . Many people think that stricter regulations are needed to control air pollution . Others argue that reducing air pollution can be very expensive and that the benefits of stricter regulations may not be worth the costs . Reading Explain one way that air quality could , be Improved . Asses Section Vocabulary Skill Greek Word Origins you know about the ( Steel photo to explain the meaning of smog . it . I . What is the atmosphere ?

listing What are the four most common gases in dry air ?

Explaining Why are the amounts of gases in the usually shown as air ?

a . Describing are three ways in which the atmosphere is important to lite on Earth ?

I ) How would the of carbon dioxide in the atmosphere if there were no plants ?

Developing Hypotheses How would Earth be different without the atmosphere ?

069 ent Flaunt Public Public transportation , like the light rail system above . can ( air pollution . Identifying What human activity is responsible for the formation of smog and acid rain ?

Explaining What kinds of harm does photochemical smog must ?

Inferring Do you think that photochemical um I smog levels are higher during the winter or during the ?

Explain . Writing in Science Write a paragraph that summarizes In your own words how oxygen the atmosphere is important . Include its Importance to living things and In other processes . 261 Section Air Pressure Standards Does Air Have Mass ?

Use a balance to find the mass of a deflated balloon . Blow up the balloon fully and he the neck closed . Predict whether the mass of the balloon plus the air you have compressed into it will differ from the mass of the deflated balloon . Find the mass of the inflated balloon . Compare this to the mass of the balloon . Was your prediction correct ?

Think It over Drawing ( What can Focus Students know differences in pressure , heat , air movement , and humidity result in changes in weather , What are some of the properties of air ?

What instruments are used to measure air pressure ?

How does increasing altitude affect air pressure and density ?

you conclude about whether air ' has mass ?

Explain your conclusion , air pressure ' The air is cool and perfect for an overnight hiking ' mercury barometer I barometer I altitude trip . You stuffed your backpack with your tent . sleeping bag . stove . and food . When you hoist your pack onto your back , its weight presses your shoulders . That pack sure is heavy ! By like a heavy backpack the end of the day , you be glad to take it get rid of all pressing on your shoulders . the may weight of the atmosphere causes air pressure . But here a surprise liven when you your pack . your shoulders will still have pressure on them . The weight of the atmosphere itself is constantly pressing on your body .

Properties of Air it may seem to you that air has no mass . But in fact , air consists of atoms and molecules , which have mass . 50 air must have mass . Because air has mass , it also has other properties . including density and pressure . Density Recall that the amount of mass in a given volume of air is its . You can calculate the density of a stance by dividing its mass by its volume . if there are more molecules in a given volume , the density is greater . If there are fewer molecules . the density is less The force pushing on an area or surface is known as pressure . The weight of the atmosphere exerts a force on surfaces . is the result of the weight of a column of air pushing down on an area . The column of air extends upward through the entire atmosphere . as shown in Figure . The atmosphere is heavy . The weight of the column of air above your desk is about the same as the weight oi a large schoolbus . So why doesn air pressure crush your desk ?

The reason is that the molecules in air push in all , up . and sideways . The air pushing down on top of your desk is balanced by the air pushing up on the bottom of your desk . Air pressure can change from day to day . A denser stance has more mass per unit volume than a less dense one . So denser air exerts more pressure than less dense air . How does the density of air ) affect air pressure ?

Hours Air Pressure There is a column of Ill above you all the time . The weight of the air in the atmosphere causes air pressure .

FBI ! Mercury Barometer Air pressure pushes down on the surface of the mercury in the dish . causing the mercury in the tube to rise . The air pressure is greater on the barometer on the right . mercury is higher in the tube . Predicting What happens to the level of mercury In the tube when the air pressure decreases ?

Go For Air Visit Web Code 2540 lower Alr . Air Mercury Air pressure Alr pressure Measuring Air Pressure A barometer ( RAHM uh ) is an instrument that is used to measure air pressure . No kinds of are mercury barometers and anemic ! barometers . Mercury Barometer ! Figure shows the way a mercury barometer works . A mercury barometer consists of a glass tube open at the bottom end and partially with mercury . The space in the tube above the mercury is almost a it contains very little air . The open end of the tube nests in a dish of mercury . The air pressure pushing down on the surface of the mercury in the dish is equal to the pressure exerted by the weight of the column of mercury in the tube . When the air pressure increases . it presses down more on the surface of the mercury . Greater air pressure forces the column of mercury higher . At sea level the mercury column is about 76 meters high . on average . Aneroid Barometer lfyou have it barometer at home , it is probably an aneroid barometer . The word aneroid means without An asteroid barometer ( AN uh ) has an airtight metal chamber . The metal chamber is sensitive to changes in air pressure . When air pressure increases . the thin walls of the chamber are pushed in . When the pressure drops , the walls bulge out . The chamber is connected to a dial by a series of springs and levers . As the shape of the chamber changes . the needle on the dial moves .

Units of Air Pressure Weather reports use several units for air pressure . Most weather reports for the general public use inches of mercury . For example , if the column of mercury in a mercury barometer is 30 inches high , the air pressure is 30 inches of mercury or just 30 inches . National Service maps indicate air pressure in mi . One inch of is , so 30 inches of mercury is approximately equal to . halal ej ?

Altitude and the Properties of Air At the top of a mountain . the air pressure is less than the air . pressure at sea level . Altitude . or elevation . is the distance in an . i , a , above sea level , the average level of the surface of the oceans . in air pressure cause the walls at Air pressure decreases an altitude increases . As air ' in and out . This causes the needle Pram so due ' on the barometers dial to move . Altitude Affects Air Pressure Imagine a stack of books . Which book has more weight on it , the second book from the top or the book at the bottom ?

The second book from the top has only the weight clone book on top of it . The book at the bottom of the stack has the weight of all the books pressing on it . Air at sea level is like the bottom book . air has the weight of the whole atmosphere pressing on it . So air pressure is greater at sea level . Air near the top of the atmosphere is like the second book from the top . There , the air has less weight A pressing on it . and thus has lower air pressure .

Density at Mu 10 . kilometers Altitude and Density The density of air decreases as altitude increases . Air at sea level has more gas in each cubic meter than air at the top of a mountain . Altitude Also Affects Density As you go up through the ' atmosphere . the density of the air decreases . means the gas ' molecules that up the are farther apart at high The altitudes than they are at sea level . you were near the top at tall mountain and tried to run . you would quickly get out of breath . Win ?

The 21 percent oxygen . whether you arc at sca level or on top of a mountain . However . since the air is less dense at it high altitude . are fewer molecules to in each cubic meter ofair than at sea level . So you would short of breath quickly at high altitudes . Hurling ! Section Assessment Target Reading Skill Take Notes Review ) note for this section . What are two important ideas that you wrote under the heading Altitude and ?

Reviewing Key Concepts . Defining What is air pressure ?

Explaining How dues the ) of a tax El affect its pressure ?

a . Lining What two instruments are commonly used to measure an re ! Measuring What units are commonly used to measure air Calculating are equal to of mercury ?

MINT a . Defining What is altitude ?

Relating Cause and Effect A altitude . how HINT dues air . change ?

How range ?

I changes in air would you expect if you carried at at mine shaft ?

Why is it hard to breathe at the top of a mountain ?

HA Reading Model Air Pressure Here how you can show your family that air has pressure . Fill a glass with water . Place a piece at cardboard over the top of the glass . Hold the cardboard in plate with one hand as you turn the glass upside down . CAUTION Be sure the cardboard does not bend Now remove your hand from the cardboard . What happens ?

Explain to your family that the cardboard does fall because the air pressure pushing up on it is greater than the weight of the water pushing down .

Section Layers of the Atmosphere A ( Auto Standards Focus I Students know in pressure , heat , air movement , and humidity result in changes In weather . What are the four main layers of the atmosphere ?

what are the characteristics of each layer ?

Key troposphere stratosphere mesosphere I temperature ionosphere exosphere ' A balloon is Air There ?

Use a heavy rubber band to tightly secure a plastic bag over the top of a jar . Gently try to push the bag into the jar . What happens ?

Is the air pressure higher inside or outside the bag ?

Remove the rubber band and line the inside of the jar with the plastic bag . Use the rubber band to tightly secure the edges of the bag over the rim of the jar . Gently try to pull the bag out of the jar with your fingertips . What happens ?

Is the air pressure higher inside or outside the bag ! Think It Over Predicting Explain your observations in terms of air pressure . How do you think differences in air pressure would a balloon as it traveled up through the atmosphere ?

imagine taking a trip upward into the atmosphere in a balloon . You begin on a warm beach near the ocean . at an of kilometers above sea level . You hear a roar as the pilot turns up the burner to heat the air in the balloon . The balloon begins to rise . and Earth surface farther and away . As the balloon rises to an altitude of kilometers , you realize that the air is getting colder . As you continue to rise . the air gets still . At kilometers you begin to have trouble breathing . The air is becoming less dense . time to go back down . What if you could have continued your balloon ride up through the ?

As you rose higher . the air and temperature would change dramatically . Scientists divide atmosphere into four main layers according to changes in temperature . These layers are the troposphere . the stratosphere . the , and the . Read on to learn more about each of these layers 257

11 Weather Balloon This weather balloon will carry a package of instruments to measure weather conditions high in the atmosphere . Applying Concepts Which is the first layer of the atmosphere that the balloon passes through on in way up ?

Go Online For More on the ozone layer Visit Web Code ( The Troposphere You live in the inner . or lowest . layer of Earth atmosphere , the troposphere ( puh ) means tuming or Conditions in the troposphere are more variable than in the other layers . The troposphere is the layer of the atmosphere in which weather occurs . Although balloons can not travel very high into the troposphere . other types of balloons can . To measure weather conditions . scientists launch weather balloons that carry instruments up into the atmosphere . The balloons are not fully inflated before they are launched . Recall that air pressure decreases as you rise through the atmosphere . Leaving the balloon only partly the gas inside the balloon room to expand as the air pressure outside the balloon decreases . The depth of the troposphere varies front kilometers above the equator to less than kilometers above the North and South poles . Although it is the shallow layer . the sphere contains almost all of the mass of the atmosphere . As altitude increases in the troposphere . the temperature decreases . On average . for every increase in , the air gets about Celsius degrees cooler . At the top of the troposphere . the temperature stops decreasing and stays at about . Water here forms thin , feathery clouds of ice . The Stratosphere The stratosphere extends from the top of the troposphere to about 50 kilometers above Earth surface . means layer or spread ouL The stratosphere is the second layer of the atmosphere and contains the ozone layer . The lower stratosphere is cold , about ) Surprisingly , the upper stratosphere is than the lower stratosphere . Why is this ?

The middle portion of the stratosphere contains a layer of air where there is much more ozone than in the rest of the atmosphere . Recall that ozone is the form of oxygen . When the ozone absorbs energy from the sun , the energy is converted into heat , warming the air . The omne layer is also important because it protects Earth living things from dangerous ultraviolet radiation from the sun . As a weather balloon rises through the stratosphere . the air pressure outside the balloon continues to decrease . The volume of the balloon . Finally . the balloon bursts , and the instrument package falls back to Earth surface . Indian why is the upper warmer than the ' lower stratosphere ?

12 Layers of the Atmosphere The atmosphere is divided into four layers the troposphere , the stratosphere . the mesosphere . and the . The Phone calls and television pictures Ire by way ol satellites that orbit Earth In the . is further divided into the ionosphere and the Interpreting Diagrams Haw deep the mesosphere ?

3430 . bull ) Ions In the ionosphere radio waves bark to Earth . lire aurora occurs In the ionosphere . In ) The sienna from 10 above outward mo qua . It his no definite outer . all to II In ) Most burn in In . producing trails . 12 In 50 lull ) The layer In the stratosphere absorbs ultraviolet radiation ( to Ir ! Rain . snowl . and most clouds occur In the troposphere .

tun ma Changing Temperatures The graph shows how temperatures in the atmosphere change with altitude . Use it to answer the questions below . Reading Graphs What two variables are being graphed ?

In what unit is each measured ?

Graphs What is the ture at the bottom at the stratosphere ! Interpreting Data which layer of the . atmosphere has the lowest temperature . so an . Making Generalizations Describe how mud . temperature changes as altitude increases in the troposphere . Temperature ( The Mesosphere Above the stratosphere . a drop in temperature marks the beginning of the next layer . the . means middle . so the is the middle layer of the sphere . The mesosphere begins 50 kilometers above Earth surface and ends at an altitude of 80 kilometers . In the outer mesosphere . temperatures approach is the layer of the atmosphere that protects Earth surface from being hit by most . are chunks of stone and metal from space . What you sec as a shooting star , or meteor , is the trail of hot , glowing gases the meteoroid leaves behind in the mesosphere . The Near the top of the atmosphere , the air is very thin . At 80 meters above Earth surface , the air is only about ! percent as dense as the air at sea level . as though you took a cubic meter of air at sea level and expanded it into , 00 cubic meters at the top of the mesosphere . The outermost layer of I atmosphere is the . The extends from 80 kilometers above Earth surface outward into space . It has no outer limit . but blends gradually with outer space . The in means Even though the air in the is thin , it is very hot , up to . This is because sunlight strikes the first . gen and oxygen molecules convert this energy into heat . 270

( Reviewing Key Concepts El uh mi Despite the high , you would not feel warm in the . An ordinary wuuld show it temperature well below ( Why is that ?

Temperature is the average amount til energy of motion of each of . The molecules in the move very rapidly , so the temperature is very high . the are spaced far apart in the thin air . There are not enough of them to collide with thermometer and warm it very much . The is divided into two layers . The lower layer , called the ionosphere ( eye AHN uh steer ) begins about 80 kilometers above the surface and extends to about 400 . Energy from the sun causes gas in the ionosphere to become electrically charged cle ions . Radio waves bounce oft ions in the ionosphere back to surface . Brilliant light displays , such as those shown in Figure Li , also occur in the ionosphere . in the Northern Hemisphere , these displays are called the Northern Lights . or the aurora . Auroras are by particles front the sun that enter the ionosphere near the poles . These particles strike atoms in the ionosphere . causing them to glow . Ext means outer , so the exosphere is the outer portion of the . The exosphere extends about 400 ( outward fur of . Flooding , ionosphere ?

Assessment Section Vocabulary Skill Greek word Origins and to your word origin chart . Then describe the tour of the atmosphere . a . Listing Lint the four main layers , with the layer ( loam lo , Classifying What properties are used to distinguish the layers of the atmosphere ?

Interpreting Diagrams Figure in which layer of the atmosphere do ?

Identifying ( live at one important characteristic til each of the four main layers ol . Comparing and Contrasting Haw due change height increases in the troposphere ?

this to how temperature changes with height in the . Applying Concepts Why would you not feel warnt in the . even though temperatures can be up to , in Science cum and Effect How do you think Earth surface might be different if it had no atmosphere ?

Write a paragraph explaining your ideas . From 13 The aurora borealis , seen from Fairbanks . Alaska , creates a display in the night sky . 211 Section Energy in Earth Atmosphere in what form does energy from What happens to the sun energy Focus ma Standards know heat energy is also transferred between objects by radiation ( radiation can travel through space ) i Students know solar energy reaches Earth through radiation . mostly in the form of visible light . Does a Plastic Bag Trap Heat ?

Record the initial temperatures on two thermometers . You should get the same readings . Place one of the thermometers in a plastic bag . Put a small piece of paper in the bag so that it shades the bulb of the thermometer . Seal the bag . Cover the bulb of the second thermometer with a small piece of paper . Place both thermometers on a sunny window ledge or near a light bulb . Predict what you think will happen . the sun travel to Earth ?

en ' an Wart five minutes . Then record the temperatures on the two Key thermometers . electromagnetic wave ' Measuring Were the two temperatures the same ?

How could . you explain any difference ?

ultraviolet radiation I scattering greenhouse effect In the deserts . summer nights can be chilly . In the morning . the sun is low in the sky and the air is cool . As the sun rises . the temperature increases . By noon it is quite hot . As you will learn in this chapter . heat is a major factor in the weather . The movement of heat in the causes to change . winds to blow . and rain to fall . Energy From the Sun When does this heat come from ?

Nearly all the in Earth atmosphere comes from the sun . This energy travels to Earth as electromagnetic wives , a form of energy that can move through the vacuum of space . Electromagnetic waves are according to wavelength . or distance waves Radiation is the direct transfer of energy by electromagnetic wows , so the electromagnetic waves given oft by the sun are called solar radiation . What kinds of energy do we receive from the sun ?

is all of the energy the same ?

Most of the energy from the sun travels to Earth in the form of visible light . However , a full spectrum oi energy is present in solar radiation . 271 ' mmy , Longer wavelengths I Infrared radiation light Visible Light Visible light includes all of the colors that you we in il rainbow red , orange . green . blue , and Violet . The colors are the result of different wavelengths . Red and orange light have the longest wavelengths . while blue and Violet light have the shortest . as shown in Figure 14 . Radiation One form of energy . infrared radiation , has wavelengths that are longer than red light . infrared radiation is not visible , but can be felt as heat . The sun also gives off ultraviolet radiation . which is an invisible form of energy with wavelengths that are shorter than violet light . Ultraviolet radiation can cause . This radiation can also cause skin cancer and eye damage . Solar includes a full spectrum uf wavelengths . from below the infrared to above the ultraviolet . Ranting which color oi visible light has the longest , wavelengths ?

Shorter wavelengths it I Ultraviolet radiation VIEW ! Solar Radiation Energy lrom the sun travels to Earth across a full spectrum of wavelengths . Interpreting Diagrams What type of radiation has wavelengths that are shorter than visible light ?

Chapter 213 Energy In the Atmosphere The sun energy Interacts Earth atmosphere and surface in several ways About hall is either reflected into space or absorbed by the atmosphere . The rest reaches Earth surface . li For Links on energy in atmosphere Visit Welt Code ( 17 ! Energy in the Atmosphere Before reaching Earth surface , sunlight must pass through the atmosphere . The path of the sun rays is shown in Figure 15 . the atmosphere to the . Some solar radiation is absorbed by the atmosphere . The ozone layer in the stratosphere absorbs most of the ultraviolet radiation . Water vapor and carbon dioxide absorb some infrared radiation . Clouds . dust . and other gases also absorb energy . Some sunlight is , Clouds net like mirrors . reflecting sunlight back into space . Dust particles and gases in the sphere light in all directions . a process called stuttering , When you look at the sky , the light you see has been scattered by gas molecules in the atmosphere . Gas molecules scatter short wavelengths of visible light ( blue and violet ) more than long lengths ( red and orange ) Scattered light therefore looks bluer than ordinary sunlight . This is why the daytime sky looks blue . When the sun is rising or setting . its light passes through a greater thickness of the atmosphere than when the sun is higher in the sky and looks yellow . More light from the blue end of the spectrum is removed by scattering before it reaches your eyes . The remaining light is mostly red and orange . The sun looks red . and clouds around it become very colorful .

arget Reading Skill Take Use your Reviewing Key Concepts El EL FEE Applying Concepts Why are sunsets red ?

Energy at Earth Surface Some of the sun energy reaches Earth surface and is reflected back into the atmosphere . About half of the surfs energy . however . is absorbed by the land and water and changed into heat . When Earth surface is hated . it radiates most of the energy hack into the atmosphere as infrared radiation . As shown in Figure . much of this infrared radiation can not travel all the way through the back into space . Instead , it is absorbed by water vapor , carbon dioxide . methane . and other gases in the air . The energy the absorbed radiation heats the gases in the air . These gases a around Earth that holds heat in the atmosphere . The process by which gases hold heat in the air is called the greenhouse effect . The greenhouse effect is a natural process that keeps atmosphere at a temperature that is comfortable for most living things . Over time . the amount of energy absorbed by the and surface is nearly in balance with the amount of energy radiated into space . In this way . Earth average fairly constant . However . as you will learn . emissions from human activities may be altering this process . What is the greenhouse effect ?

Section Assessment notes to help you answer the following questions . a . Listing List three forms from the sun , In . Comparing and Contrasting Which form uf radiation from the sun has the longest wavelength ?

The shortest wavelength ?

Summarizing What happens to most of the sunlight that reaches ?

Interpreting Diagrams What percentage of incoming sunlight is reflected by clouds , dust . and gases in the atmosphere ?

Healing Your Home With an adult family member , explore the role radiation from the sun plays in heating your home . Does it make some rooms warmer in the morning ?

Are other rooms warmer in the afternoon ?

How does opening and closing curtains or blinds affect the temperature of a room ?

Explain your observations to your family . Greenhouse Effect Sunlight travels through the atmosphere to Earth surface . Earth surface then gives off infrared radiation . Much of this energy is held by the atmosphere . warming it . nu . ma a . Describing What happens to the energy from the sun that is absorbed by surface ?

Predicting How might conditions Earth HINT be different without the greenhouse effect ?

115 inquiry . Heating Earth Surface Mamie Problem How do the heating and cooling rates at sand and water compare ?

Skills FOCUS developing hypotheses . graphing . drawing . conclusions thermometers or temperature probes ' I . which do you think will heat up or water ! Record your hypothesis . Then follow these steps to test your ) Copy the data table into your notebook . Add enough rows to record data for IS minutes . Fill one beaker with 300 of dry sand . Fill the second beaker with 300 of water at room temperature . Arrange the beakers side by side beneath the ring stand . one thermometer in each beaker . if you are using a temperature probe , see your for instructions . Suspend the thermometer the ring stand with string . This and and will hold the thermometer in place so they do not fall . two ring ( lamps . Adjust the height of the ( lamp so that the bulb of eath thermometer is ( by about of sand or water in a sand and water , 300 ! beaker . Position the lamp so that it is about 20 above the sand and water . There should be no more than between the beakers . Be careful not to splash wa ter onto rhe hot light bulb . 10 . Record the temperature of the sand and water in your data table . metric ruler 11 . Turn on the lamp . Read the temperature of the sand and water every minute tor 15 minutes . Record the temperatures in the , Temperature with Light On column in the data table . Data Table With Light On With Ugh Off lamp with bulb ( stopwatch or clock graph paper

which material do you think will . Interpreting Data Review your data cool off more quickly ?

Record your again . In 15 minutes . which material hypothesis . Again , give reasons why cooled faster ?

Wu mink Wu is ( Drawing Conclusions How do these 13 . Turn the light off . Read the results compare to your second temperature of the sand and water hypothesis ?

every minute for another 15 minutes . Hypotheses Based on ?

uM your results . which do you think will De . heat up more quickly on a sunny ( day the water in a lake or the sand it ?

After dark . which II Analyze and conclude ( I . Communicating if your results did not show the data for the temperature egg , of you , 99 ' why do you think the results Label the horizontal axis from to what you ' paragraph in which you discuss the degrees Celsius . Draw both graphs on , and how hey comm , you , the same pie ( of graph paper . Use a , dashed line to show the temperature in water and a solid line to Design an Experiment show the temperature change in sand . Calculating Calculate the total change in temperature for each material . Do you think all solid materials heat up as last as sand ?

For example . consider gravel , crushed stone , or different types of soil . Interpreting Data ased on your Write a hypothesis about their heating data . which material had the greater rates . increase in temperature ?

with the approval and supervision of your teacher . develop a procedure to test your ' i ( hypothesis . was your hypothesis correct ?

you conclude about material absorbed heat taster ! How do your results compare with your hypothesis chapter 117 00 Section Heat Transfer in the Atmosphere Students know heat flows in solids hy ( which no of matter ) and in by and by ( tion ( whim involves flow or matter ) Students know that Icon currents distribute heat in the atmosphere and oceans How is temperature measured ?

In what three ways is heat transferred ?

How is heat transferred in the troposphere ?

Key I thermal energy thermometer I heat I I I current takes only a small amount of energy to heat up I cup of tu . Standards What Happens when Air Is Heated ?

Use heavy scissors to ( in the flat part out of an aluminum pie plate Use the tip of the scissors to poke a small hole in the middle of the flat part of the plate . Cut the part into a spiral shape , as shown in the photo he a ( piece of thread to the middle of the spiral . Hold the spiral over a source of heat . such as a candle . hot plate . or incandescent light bulb . Think It Over Inferring What happened to the spiral ?

Why do you think this happened . ta You pour cup of steaming tea teapot . Your is warm to the touch . Somehow . heat was from ( me ( the cup ! to your that it was ( This is an ) lI , one ways that heat can be ' you learn in this . in the plays an rule in weather .

, Thermal Energy and Temperature The tea in the cup and in the teapot are the same temperature but have different amounts of total energy . To understand this . you need to know that all substances are made up of tiny that are constantly moving . The faster the particles are moving . the more energy they have . Figure shows how the motion of the particles is related to the amount of energy they hold . Recall that temperature is the amount of energy of motion of each particle ofa substance . that is . temperature is a measure of how hot or cold a substance is . contrast , the total energy of motion in the particles of a substance is called thermal energy . The hot tea in the teapot has more energy than the hot tea in the cup because it has more particles . Measuring Temperature Temperature is one of the most important factors affecting the weather . Air temperature is usually measured with a thermometer . A thermometer is a thin glass tube with a bulb on one end that contains a liquid . usually colored alcohol . Thermometers work because liquids expand when they are heated and contract when they are cooled . When the air increases . the temperature of the liquid in the bulb also increases . This causes the liquid to expand and rise up the tube of the thermometer . Temperature Stiles Temperature is measured in units called degrees . Two temperature scales are commonly used the Celsius scale and the Fab scale . Scientists use the Celsius scale . On the Celsius scale , the freezing point of pure water is ( read zero degrees Celsius ) The boiling point of pure water at sea level is . Weather reports in the United States use the Fahrenheit scale . On the Fahrenheit scale . the freezing point ofwater is and the boiling point is . I which temperature scale do scientists use ?

Home 17 Movement ol Molecules The iced tea is cold . so its molecules move slowly . The herbal tea Is hot , so its molecules move faster than the molecules In the iced tea . inferring which liquid has higher temperature ?

Converting Units Temperatures in weather reports use the Fahrenheit scale , but scientists use the Celsius scale . Temperature readings can be converted from the Fahrenheit scale to the Celsius scale using the following equation ( 32 ) If the temperature is 68 , what is the temperature in degrees Celsius ?

32 ) Practice Problem Use the equation to convert the following temperatures from Fahrenheit to Celsius , and .

For Links on heat transfer Visit ( Web ( ode Temperature and Height How much difference is there between air temperatures near the ground and higher up ?

Give reasons for your prediction . Take all of your ments outside at a location that is sunny all day . Early in the morning , measure the air temperature and above the ground . Record the time and temperature for each height . Repeat your measurements late in the afternoon . Repeat Step for two more days . Graph your data for each height with temperature on the vertical axis and time of day on the horizontal axis . Use the same graph paper and same scale for each graph . Label each graph . Interpreting Data At which height did the temperature vary the most ?

How can you explain the difference ?

How Heat Is Transferred Recall that heat is the transfer of thermal energy from a hotter object to a cooler . is in three ways within . radiation . conduction . end convection . Radiation Have you ever felt the warmth of the suns rays on your face ?

You were feeling energy coming directly from the sun as radiation . Recall that radiation is the direct transfer of energy by electromagnetic waves . Conduction Have you ever walked barefoot on hot sand ?

Your feet felt hot because heat moved directly from the sand into your feet . The direct transfer of from one substance to another substance that it is touching is called conduction . When a moving sand molecule humps into a . the faster particle transfers some of its energy . The closer together the particles in a substance are . the more they can conduct heat . Conduction works well in some solids , such as metals . but not as well in liquids and gases . Air and water do not conduct heat very well . convection in fluids ( liquids and gases ) particles can move easily from one place to mother . As the particles move , their energy goes along with them . The transfer by the ment of a fluid is called convection . Heating the Radiation . conduction . and vection work together to heat the troposphere , During the day , the sun radiation heats Earth surface . The land than the air . Air near Earth surface is by both lion and conduction . However , heat is not easily transferred from one air particle to another by conduction . Only the lirst few meters of the troposphere are heated by conduction . Thus , the air close to the ground is usually warmer than the air a few meters up . Within the troposphere . heat is transferred mostly by convection . When the air near the ground is heated , in particles move more rapidly . As a result . they bump into each other and move farther apart . The air less dense . Cooler . denser air toward the surface . forcing the warmer air to rise . As the warm air rises , it cools and becomes more dense . This denser cool air sinks back toward the ground where it may be heated once again . This upward movement of warm air and the downward movement of cool air form currents . currents move heat throughout the troposphere . Hurling How is the air near Earth surface heated ?

II ( Heat by . radiation Heat Section by In Heat All three types of heat radiation . conduction . and to warm the troposphere . Assessment Skill Greek Word Use what you learned about the Greek word thermos to explain the meaning of enema ( Reviewing Key Concepts MINT a . Defining What is temperature ?

Identifying What instrument is used to measure air temperature ?

WE Comparing and Contrasting A pail of water is the same temperature at a lake , the amount of thermal energy of the water in the lake and the winter in Ihe pail a . Naming Name three ways that heat can be . Describing How do the time types of hut transfer work together to heat the troposphere ?

Identifying What major heal is transferred in the troposphere ?

Applying Concepts Explain how a hawk or inner eagle could use convection currents to soar upward without it wings . Converting Units Use the equation from the Math Skills Activity to convert the following temperatures from Fahrenheit to Celsius . 86 ?

77 , and 97 281 Section Winds , Standards Focus 00 Students know different in pressure , heat , air movement , and humidity result in changes in weather what winds ?

How do local windy and global winds differ ?

Where are the major global wind belts ?

Key Terms I wind I I factor I local wind I sea breeze I land breeze I global wind I I latitude ' jet stream A kite festival in Cape Town . South Africa 2810 Standards , Does the Wind Turn ?

Do this activity with a partner . Let the ball represent a model of Earth and the marker represent wind . Using tape . attach a pencil to a large smooth ball so that you can spin the ball from the top without touching it . One partner should hold the pencil . Slowly turn the ball counterclockwise when seen from above . While the ball is turning , the partner should use a marker to try to draw a straight line from the North Pole to the equator of the ball . What shape does the line form ?

Think It Over Making Models It cold air were moving south from Canada into the continental United States . how would its movement be affected by Earth rotation ! Have you ever a kite ?

Start by unwinding a few of string with the kite downwind from you . Have a friend hold the kite high . Then . as your friend releases the kite . directly into the wind . If you lucky . the kite will start to rise . the kite i table , you can unwind your string to let the wind lift the high into the sky . But what exactly is the wind that the kite . and what causes it to blow ?

What Is Wind ?

Because air is a fluid . it can move easily from place to place . Differences in air pressure cause the air to move . A wind is the horizontal movement of air front an area of high pressure to an area of lower pressure . Winds are caused by differences in air pressure . Most differences in air pressure are caused by the unequal heating of the atmosphere . Convection currents form when an area of surface is heated by the sun rays . Air over the heated surface expands and becomes less dense . As the air becomes less dense , its air pressure decreases . If at nearby area is not heated as much , the air above the area will be cooler and denser . The cool . dense air with higher pressure underneath the . less dense air . This forces the warm air to rise . Measuring Winds are ( by their direction and speed . Wind is determined with wind vane . The wind swings the wind vane so that one end points into the wind . The name ofa wind tells you where the wind is coming from . For example , south wind blows from the south toward the north . A north wind blows to the south . Wind speed can be measured with an ( an uh ( AHM uh tur ) An has three or four cups mounted at the ends of spokes that spin on an axle . The force of the wind against the cups turns the axle . meter on the axle the wind speed . Factor On a warm day . a cool breeze can he refreshing . But in winter . the saline breeze can make you feel cold . The wind blowing over your skin body heat . The stronger the wind . the colder you feel . The increased cooling wind can cause is called the . Toward what does a west wind blow ?

mun 19 Speed The on the right measures wind speed . The cups catch the wind . turning faster when the wind blows faster . Build a Wind Vane . Use scissors to cut out a pointer and a slightly larger tail fin from construction paper . Make a slit deep in each end of a soda straw . Slide the pointer and tail fin into place on the straw . securing them with small pieces of tape . A . Hold die straw on your linger to find the point at which it balances . Carefully push a pin through the balance point and Into the eraser of a pencil . Make sure the wind vane can spin freely . Observing How can you use your wind vane to tell the direction of the wind ?

20 Local Winds During the day . cool air moves from the sea to the land , creating a sea breeze At night , cooler air moves from the land to the sea . Forming Definitions What type of breeze at night ?

2049 Local Winds Have ever noticed a breeze at the beach on hot summer day ?

Even it there is no wind inland . there may be a cool breeze blowing in from the waiter . This is an example local wind . local winds are winds that blow nver shon distances . Local winds are caused by the unequal heating of surface within a small urea . winds form when winds are weak . Sea Breeze Unequal heating often the slime iii a large body . It takes mure energy to warm up it body water than it does to warm up an equal amt . As the sun heats Earth surface during the day , the land warms up faster than the water . As a result . the air over the land becomes than the air over the water . The warm air expands and rises , creating it area . Cool air inland from over the waiter and moves the warm air , causing a sea . A sea breeze or a brew is a local wind that blows from an ocean or lake Figure 20 shows sea breeze Land Breeze At night , the is reversed . Land ) more quickly than water , so the air over the land cooler than the air over the water . As the over the waiter expands and rim . air from the land beneath it . The from land In a body of water is called at breeze . Sea Breeze . Land

Global Winds Global winds are winds that blow steadily from specific directions over long distances . like local winds . global winds are created by the unequal heating of Earth surface . But unlike local winds , global winds occur over a large area . Recall how the surfs radiation strikes Earth . In the middle of the day near the equator . the sun is almost directly overhead The direct rays from the sun heat Earth surface intensely , Near the poles . the suns rays strike surface at a lower angle . The sun energy is spread out over at larger area . so it heats the surface . As a result , temperatures near the poles are much lower than they are near the equator . Mon direct sunlight Sun rays Global Convection Currents How do global winds develop ?

31 differences between the equator and the poles ' es ' om me duce giant convection currents in the atmosphere . Warm air rises sun mikes Em at the equator , and cold air sinks at the poles . Therefore air , same amour sure tends to ( near the equator and greater mar the poles . of 55 ! This in pressure causes at Earth surface to blow am from Lhe poles toward the equator Higher in the atmosphere , however . air away from the equator toward the poles . Those air movements produce global winds . The Effect Earth did not rotate , global winds would blow in straight line from the poles toward the equator , Because Earth is rotating . however . global winds do not follow a straight path . As the winds blow . Earth rotates from west to east underneath them . making it seem as if the winds have . The way Earth rotation makes winds curve is called the ee on list . Because of the effect . global winds in the of Earth gradually turn toward the right . As Figure 22 . shows , a wind blowing toward the south gradually turns toward the southwest . In the Southern Hemisphere . winds curve toward the left . needing way do winds tum In the ?

Southern Hemisphere ?

if I at Earth Fawn 11 did not rotate Meet As Earth rotates , the effect turns winds in the Northern toward the right . clamor ! 0255 13 Ocean Selling Sailing ships relied on global winds to speed their Journeys to various ports around the world . Applying Concepts Maw effect do you think the prevailing winds have on shipping today ?

2860 Global Wind Belts Global convection currents and other factors combine to produce a pattern of calm areas and wind belts around Earth , as shown in Figure 24 . The calm areas include the doldrums and the horse latitudes . The major global wind belts are the trade winds . the polar , and the prevailing westerlies . Doldrums Near the equator . the sun heats the surface strongly . Warm air rises steadily , creating an area of low sure . Cool air moves into the area . but is warmed rapidly and rises before it moves very far . There is very little horizontal motion . so the winds near the equator are very weak . Regions near the equator with little or no wind are called the doldrums . Horse Latitudes Warm air that rises at the equator divides and ( lows both north and south . Latitude is distance from the equator . measured in degrees . At about 30 north and south latitudes , the air stops moving toward the poles and sinks . in each . another belt of calm air forms . Hundreds of years ago . sailors becalmed in these waters ran out of food and water for their horses and had to throw the horses board . Because of Ibis , the latitudes north and south of the equator came to be called the horse latitudes . Trade Winds When the cold air over the horse latitudes sinks , it produces a region of high pressure . This high pressure causes surface winds to blow both toward the equator and away from it . The winds that blow toward the equator are turned west by the effect . As a result , winds in the Northern Hemisphere between 30 north latitude and the equator generally blow from the northeast . In the Southern Hemisphere between south latitude and the equator . the winds blow from the southeast . For hundreds of years . sailors relied on these winds to move ships carrying valuable cargoes from Europe to the West Indies and South America . As a result . these steady easterly winds are called the trade winds . Prevailing Westerlies In the . between 30 and north and south , winds that blow toward the poles are turned toward the east by the . Because they blow from the west to the east , they are called prevailing . The prevailing westerlies blow generally from the west in north latitudes and front the northwest in south latitudes . The prevailing westerlies play an important part in the weather of the United States .

Flaunt 24 Global Winds A sauna at wind halts Earth Between the wind belts are ( aim areas where air Is or , Whith global wind boll woulda Sailor choose to sari from to Europe ?

blew away from the horse latitudes . Trade Winds blow from the horse latitudes toward the equator . Go ' I . Ihr for Visit Web Code Polar Horse Latitudes are ( aim areas of falling air , Polar blow cold air away from the poles .

flaunt 25 Polar Cold air near the poles sinks and flows back toward lower latitudes . The effect shifts these ' i ' st ed polar winds to , the polar . The pola moan , I lIt , meet wester ies at at out 60 By traveling east In a jet stream , and south latitudes . along at region called the polar from . 53 ?

The mixing of warm and cold air along the polar front has a major effect on weather in the United States . Jet Strum About 10 kilometers above Earth surface are bands of winds called jet stream . These winds are hundreds of kilometers wide but only a few kilometers deep . let streams generally blow from west to east at speeds of 200 to 400 kilometers per hour . as shown in Figure 25 . As jet streams travel around Earth , they wander north and south along a wavy path . i What an the mums ?

Assessment ' Target Reading Take Notes Review Name the three major global your notes for this section . What important idea wind belts . did you include about the effect ?

the thug major nun Reviewing Key come , global wind belts and where they are located . Diagrams Use Figure 22 and I Ming wind ?

Figure 24 to describe how the effect ' the direction of the trade winds in . unit , a but itl ' windy outside . Use the concept chill factor to explain why it may be it good ' winds ?

Writing 509 ?

Summarizing What causes local winds ?

Comparing And Contrasting Compare the . conditions that cause a sea brew with those that cause a land breeze . or ?

Explain how the wind you decision .

Technology Lab Guided Inquiry . Measuring the Wind Problem can you design and build an to measure the wind ?

Design Skills evaluating the design . redesigning Procedure . Begin by making a simple anemometer that uses wooden coffee stirrers to indicate wind speed . On a piece of cardboard . draw a curved scale like the one shown in the diagram . Mark it in equal intervals from to . carefully use a pencil to make a small hole where a toothpick will go . Insert a toothpick through the hole . Tape two wooden coffee stirrers to the toothpick as shown in the diagram , one on each side of the cardboard . Copy the data table into your notebook . Data Table Location Wind Speed I . Take your anemometer outside the school . Stand about away from the building and away from any corners or large plants . Use the wind vane to out what direction the wind is coming from . Hold your so that the card is straight , vertical . and parallel to the wind direction . Observe the wooden stirrer on your anemometer for one minute . Record the highest wind speed that occurs during that time . Repeat your measurements on all the other sides of the building . Record your data . Analyze and conclude . Interpreting Data Was the wind stronger on one side of the school than on the other sides ?

Explain your observations . Applying ( Based on your data , which side of the building provides the best location tor a door ?

Evaluating the Design Do you think your anemometer accurately measured all of the winds you encountered ?

How could you improve its accuracy ?

What was the hardest part at using your ?

How could you change your design to make it more useful at very low or at very high wind speeds ?

Explain . Working with Design Constraints How did having to use the materials provided by your teacher affect your ?

How would your design have changed if you could have used any materials you wanted to ?

Communicate Write a brochure describing the benefits of your . Make sure your brochure explains how the works and its potential uses . Wooden stirrers Keep this edge Keep this edge parallel to the ground Chapter ' The Air Around You ( Key Concepts atmosphere is made up of , oxygen , dioxide . water vapor . and many other gases . as well as liquid particles and solids . Earth atmosphere makes conditions on for living things . Hunting fossil fuel ) stint smog and acid nun . Key Terms weather I atmosphere I won water vapor pollutant photochemical smog acid Mill Air Pressure Key Concepts Became air has runs . it also has other properties , including density and pressure . mo kinds of are mercury barometer and . Air pressure decreases in altitude , As pressure decreases . so does . Key Terms density pressure air pressure I I ' Layers of the Atmosphere Key Concepts Scientists divide Earth atmosphere into four main layers the troposphere . the . the . and the . The is the layer the atmosphere in which weather occurs . The con the ozone layer . The protects surface from most . The outermost layer of atmosphere is the ' Key Terms 2900 Study Guide Air pressure Ind vary with Altitude Ind . resulting in distinct atmospheric layers and predictable wind . Energy in Earth Atmosphere Key Concepts i Most energy from the sun travels to Birth in the form of visible light . Some sunlight is absorbed or hy the atmosphere before it can reach the surface . When the is heated , it energy back into the atmosphere as radiation . Key Terms waves radiation infrared radiation ultraviolet radiation scattering greenhouse Heat Transfer in the Atmosphere Key Concepts . is with thermometer . Heat is in three ways , conduction . and convection . Radiation , conduction . and convection work together to heat the troposphere . Key Terms temperature thermal energy thermometer heat I convection convection current winds Key Concepts Winds are caused by in air pressure . Local are by the unequal healing of surface within a small area . Global winds are created by the unequal heating of surface over large area . a Major global belts are the trade winds . the polar , and the prevailing Key Terms wind factor local wind sea breeze land breeze global wind latitude jet stream

Review and Assessment I arget Reading Skill In your ( uI ! organizer that you earlier for Section . Include . um For Visit Web Code Real Clues and Questions I Notes The Air Around You what are pollutants ?

What are some sources of air pollution ?

harmful substances In the air , water . or Soil Sources of Pollution Natural Reviewing Key Terms Choose the letter of the best answer . The most abundant gas in the is ozone . en . Air pressure is measured with a . satellite . tir balloon . The layers of the atmosphere are according to in a altitude . air pressure . Energy from the sun travels to Forth surface hy radiation . convention . Rising warm air transports thermal energy by conduction . convection . condensation . Complete the following sentences so that your answers clearly explain the key terms . Air contains varying at water vapor . ill ?

is man i . The daytime sky looks ) of scattering . a process in which . Earth is Wal . the greenhouse effect , which is . Convection currents . which are . mow heat throughout the troposphere . i 10 . At night you may a sea . which occurs when Suppose you are on a balloon to the upper levels of the troposphere . Describe how the properties of the atmosphere , as air pressure and amount or oxygen . would change during your trip . II The A chum 291

Review and Assessment Checking Concepts 11 . Explain why it is to include water vapor in A graph that shows the percentages of various gases in atmosphere . 12 . Name two ways in which carbon dioxide is added in . 13 . Describe the temperature that occur as you upward through . 14 . Describe examples of radiation . conduction . and convection your daily . 15 . Explain how movements of air at the equator and poles produce global patterns . Math 16 . Converting Units What is ( in degrees ' 17 . Converting Units What is 30 in degree ?

Thinking Critically 18 . Applying Concepts Why aneroid be used to indicate changes in elevation as well as air ?

19 . Reading Graphs According to graph below , what is the air ) i . at an of ?

in general . how does air pressure change with altitude ?

Air Pressure and Altitude Altitude ( kilometers ) 4100 600 800 ION Pressure ) 191 20 . Why are clouds at the top of the troposphere made oi crystals rather than drops of water ?

21 . Inferring Venus has an that is mostly carbon dioxide . How do you think the greenhouse has Venus ?

22 . Relating Cause and Effect What stances could cause a nighttime land breeze in a city near this ocean ?

Applying Skills Use the table below to answer the questions that follow . at various ' an a day . Altitude ) Temperature 13 . Graphing Malt at line graph in the . Put temperature on the horizontal axis and altitude ( III the vertical axis . your graph . 24 . Reading Graphs about what height above the ground was the temperature ( Zi 25 . Reading Graphs What was the temperature ?

26 . Calculating Suppose an airplane was about i above Omaha on this day . What was the at kilometers ?

How much ( older was the at kilometers above the than at ground level ?

Standards investigation Performance Assessment Decide how to present your weather in the class . For could put your graphs and on a poster or use a computer to make slide show . Marlo sure your are neatly drawn and easy in .

Choose the letter of the best answer . I . What two gases make up approximately 99 of Earth atmosphere ?

A nitrogen and carbon dioxide oxygen and carbon dioxide nitrogen and hydrogen nitrogen and oxygen A , In the troposphere . as altitude increases A air pressure decreases . I temperature decreases . air density decreases . all ofthe above iv . Layers Altitude ( use the diagram above and your knowledge of science to answer Questions and . Use the diagram In estimate the depth ' the stratosphere . A about 50 kilometers about 40 about 30 about 20 kilometers . According to the diagram . where is a when it is 75 kilometers above surface ?

A the I the stratosphere the the troposphere Son Standards Practice Orin ) Use the table below and your knowledge of science to answer Questions and . The row with a wind speed of shows the actual air temperature . Temperature Index Wind Speed Equivalent Air temperature ( i i . On a windy winter day . the actual air temperature is ST and the wind speed is kilometers per hour . What would the chill factor make the temperature feel like to person outdoors ?

A ( Use trends shown in the data table to predict how cold the air temperature would feel if the actual temperature was and the wind speed was 25 . A about I about ' The energy that reaches Earth is mostly in the form A light I gamma rays . ultraviolet radiation infrared radiation . What is the main method by which heat is transferred within the troposphere ?

A radiation conduction convection the Idea . Explain how the uneven heating of the atmosphere produces global winds . 0193 , ti