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INTRODUCTION Theearthissurroundedbyamixtureofgaseswecalltheatmosphere.Theairwebreatheispartoftheatmosphere. Theatmosphereiscomposedofaseriesof layer.Themostimportantlayeristhetroposphere.ThetroposphereisuncontactwiththeEarth’ssurface. The atmosphere is fundamental to the existence of life. Unfortunately, humanactivityispollutingtheatmosphere

1.PARTSOFTHEATMOSPHERE TheatmosphereisalayerofgasthatsurroundstheEarth.It has five layers: the troposphere, the stratosphere, themesosphere,thethermosphereandtheexosphere. Thetroposphereisthelayerthatextendsfromthesurfacetoaheightofabout15km.

Thisiswhereweatherphenomenalikewind,cloudformation,rainorstormstakeplace.

The layer above the troposphere is the stratosphere. Itextendsto50kmandcontainstheozonelayer. The mesosphere extends to 80 km. At the top of themesosphere,thetemperaturedecreasesto-100°Candtheamountofairdecreaseswithaltitude. Thethermosphereextendstoanaltitudeof500km.Here,the temperature increases to 1500°C. The lower part of thethermospherecontainsasub-layercalledtheionosphere. Theexosphereextendstoabout1000km,wherethere isnolongeranyairandthetemperatureisstable. Activities

1. True/false.TheatmosphereArethefollowingsentencestrueorfalse?

a) Atmosphericphenomenatakeplaceinthestratosphere.b) Thetemperatureoftheatmospheredecreasesmoreorlessconstantlyfromthe

Earth’ssurfacetothehighestlayer.c) Theexosphereistheoutermostlayeroftheatmosphere.d) Theionospherereflectsradiowaves.e) Theozonelayerislocatedbetweenthetroposphereandthestratosphere.f) Thethicknessoftheatmosphereisvariable.

2. Putinorder.Partsoftheatmosphere

PutthelayersoftheatmosphereinorderfromthenearesttothefarthestfromtheSun1.______________________2.______________________3.______________________4.______________________5.______________________6.______________________

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3. Choose.LayersoftheatmosphereMatcheachatmosphericlayerwithitscharacteristic

• Stratosphere -itreachesanareawherethereisnoair.

• Exosphere -layerwiththelowesttemperature.• Mesosphere -layerclosesttotheEarth´ssurface.• Thermosphere -itcontainstheozonelayer• Troposphere -itcontainstheionosphere

4. Answer.Partsoftheatmosphere

Whatisthenameoftheatmosphericlayerwelivein?Howfardoesitextend?

5. Answer.PartsoftheatmosphereHowdotemperatureschangeinthetroposphere?Andthedensityoftheair?

6. Answer.PartsoftheatmosphereInwhichpartoftheatmospherecanshootingstarsbeseen?

7. Answer.PartsoftheatmosphereInwhichpartoftheatmosphereistheionosphere?Whathappensinthissub-layer?

8. Reflect.TheatmosphereWhatistheatmosphere?

9. Reflect.TheatmosphereInwhatpartofthetroposphereistherelife?whyaretherenootherlivingbeingsintherestoftheatmosphere?

10. Reflect.TheatmosphereInwhatpartoftheatmospheredometeorologicalphenomena,suchasclouds,windorrain,takeplace?

11. Reflect.TheatmosphereInwhichlayeroftheatmosphereareradiowavesreflected?Andinwhichlayeroftheatmospheredoestheauroraborealisoccur?

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2.THECOMPONENTSOFAIR2.1.Air:amixtureofgases Air is made up of a mixture of gases. Themain gases are nitrogen and oxygen.Other gases such as water vapour, carbon dioxide and ozone are present in smallerquantities.2.2.ThecompositionofairThemaincomponentsoftheatmosphere

• Nitrogen (78%)andoxygen(21%)are themain components of air: Nitrogen isnecessary for all living things to grow.Humansdonot takenitrogen from the air,but through consuming plants that havefixed the nitrogen from the air. Nitrogenreturns to the atmosphere when organicmatter decomposes. This completes thenitrogencycle

• Oxygen (O2) is used by living things inrespiration. Plants return this oxygen backto the atmosphere through the process of photosynthesis. This completes theoxygencycle.

Theminorcomponentsoftheatmosphere

• Theminorcomponentsofairare:Watervapour.Theamountofwatervapour inthe atmosphere varies. Water vapour enters the atmosphere through theevaporation ofwater from the oceans, seas, lakes and rivers.Water vapour alsoreturnstotheatmosphere

Activities

12. Answer.Theairanditscomponents1Namesomeofthemaincomponentsoftheatmosphere.

13. Answer.TheairanditscomponentsNamesomeofthemaincomponentsoftheatmosphere.2223

14. Answer.TheairanditscomponentsWhatisair?

15. Answer.TheairanditscomponentsHastheEarth'satmospherealwaysbeenasitistoday?

16. Answer.Theairanditscomponents

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Wheredoesthewatervapourintheairwebreathecomefrom?

17. Answer.TheairanditscomponentsWheredoesthenamegreenhouseeffectcomefrom?

18. Answer.TheairanditscomponentsWhatdoestheozonelayerdo?THEATMOSPHERICPRESSURE Theatmosphericpressureistheweightorpressureexertedbyacolumnofairperunitareaontheearth’ssurface.Theatmosphereexertsapressureonallobjectsandlivingthings.at sea level, atmospheric pressure has a value of 1.013 hectopascals (hpa) or 1atmosphere(atm)3. AIRPOLLUTION3.1.Whatisairpollution? Forlifetoexist,itisessentialthatthecompositionofairremainsstable.Whenwepollute theair,wearechanging its composition.Whenweaddor removeanycomponent,wecanproducenegativeeffects.3.2.Airpollution Ourairbecomespollutedwhenweusemeansof transport that runonpetrolordieselandwhenweburnrubbishandwaste.Themainsourcesofpollutionare:Theenginesofcars,lorriesandplanes,Industriesandfactories,whichusecoal,fuelordiesel.Primaryandsecondarypollutants Therearetwotypesofpollutants:primaryandsecondary.

• Primary pollutants are pollutants produceddirectlybyvariousdifferentsources.Cars,lorriesandplanes are examples of sources of pollution.They release carbon and nitrogen oxides,hydrocarbons and toxic metal particles into ouratmosphere. Factories and power stations areother examples of sources of pollution. Theyrelease sulphur oxides into the air. These areprimarypollutants

• Secondary pollutants are those pollutantsgenerated from the interaction of primarypollutants.

Thepiechartshowsthepercentagesof thesourcesofairpollution

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Activities

19. Complete.PollutionCompletethetextwiththemissingwords:Effects-concentration-essential-fundamental-health-polluted“For life to exist onEarth, it is____________ that the composition of the air does not change,becauseeachcomponenthasa________role.Whentheatmospherebecomes_______withothergases or the________________ of its natural components changes, negative _________ for the__________________oflivingbeingscanbeproduced.”

20. Choose.PollutantsArethefollowingsubstancesprimaryorsecondarypollutants?

• Hydrocarbons_________________• Carbonicacid_________________• Nitricacid__________________• Carbonmonoxide____________• Sulphuricaci_________________• Nitrogenoxide_______________• Toxicmetalparticles________

21. Answer.Airpollution

Givesomeexamplesofactivitiesthatcauseairpollution.

22. Answer.Airpollution

Whatisthedifferencebetweenprimaryandsecondarypollutants?

23. Reflect.Sourcesofpollution

Whatisairpollution?

24. Reflect.Sourcesofpollution

Whatshouldindustriesandfactoriesdotoreducethepollutantstheyreleaseintotheair?4.POLLUTION,ENVIRONMENTANDHEALTH4.1.Environmentaleffectsofpollution Theeffectsofpollutionareharmful.Themostimportanteffectsarethedepletionoftheozonelayer,thegreenhouseeffectandacidrain.DepletionoftheozonelayerSomeairpollutants,especiallygasesinsomeaerosolsandfridges,causeareductioninthethicknessoftheozonelayer.

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ThedepletionoftheozonelayerhasnegativeeffectsonlivingthingsbecausetheyarelessprotectedfromtheharmfulraysoftheSun.Anincreaseinthenaturalgreenhouseeffect CarbondioxideisaddedtotheatmospherewhenItisproducedbytheenginesofcars,lorriesorplanes.Thisiscausinganincreaseinthenaturalgreenhouseeffect Asaresultofthis,thetemperatureonEarthisincreasing.Thisiscausingchangesintheclimate,calledclimatechange. These changes include melting ice caps, rising sea levels and desertification.Climatechange is increasing thenumberofnaturaldisasters suchashurricanes, stormsand prolongeddroughts.

ThegreenhouseAcidrain Secondarypollutantsproduceacidrain.This falls to thegroundwhen itrainsorsnows. Acid rain harms life both on land and in lakes, rivers and seas. It even affectsbuildingsbychemicallyweatheringstone.Effectsonthehealth Airpollutionisbadforthehealthoflivingthings.Itparticularlyaffectspeoplewholiveorworkinindustrialareasorlargecities. Themost commonhealthdisorderare respiratoryproblems (asthma,bronchitis,etc.)heartproblems,itchyeyes,allergiesanddigestiveproblems. ThethinningoftheprotectiveozonelayercausessunburnandskincancerActivities

25. Match.EffectsofpollutionMatchthepollutantwithitseffectontheenvironment:Sulphuricacid climatechangeCarbondioxide depletionoftheozonelayer

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Gasesfromaerosolsandfridges acidrain3435363738394041

26. Answer.Pollution,theenvironmentandhealthWhatisacidrain?

27. Answer.Pollution,theenvironmentandhealthWhichcommunitiesofpeoplearemostatriskfromthenegativeeffectsofairpollution?

28. Answer.Pollution,theenvironmentandhealthWhatcausesanincreaseinthenaturalgreenhouseeffect?

29. Answer.Pollution,theenvironmentandhealthNamesomeoftheeffectsonhealthcausedbyairpollution.

30. Answer.Pollution,theenvironmentandhealthListsomeoftheconsequencesofclimatechange.5.THEATMOSPHEREANDWEATHER5.1.Weatherandclimate Weather refers to the atmospheric conditions (temperature, humidity,atmosphericpressure,windandcloudcover)inaparticularplaceataparticulartime. Climatereferstotheweatherinaparticularplaceoveralongperiodoftime.TherearedifferentclimatesindifferentplacesonEarth.5.2.Atmosphericpressure Atmospheric (air) pressure is theweight or pressure exertedby a columnof airperunitareaontheEarth'ssurface. Thinkofahugeswimmingpool. Imaginewe livedat thebottomof thispool.Wewould notice the weight or pressure of the water above us. Similarly, the atmosphereexertsapressureonallobjectsandlivingthings.5.3.Temperature When the Sun’s rays reach the Earth, they heat the Earth’s surface. This heat istransmittedtothesurroundingair.TheatmospherictemperaturetellshowmuchtheEarth’sradiationofthesolarenergyhasheatedtheair.5.4.Airhumidity Humidityistheamountofwatervapourintheair.Watervapourcomesfromthewater that has evaporated from seas, oceans, rivers, and lakes, and the transpiration ofplants.Activities

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31. Match.MeteorologicalInstrumentsMatcheachmeteorologicalinstrumentwiththeweathervariableitrecords.

• Winddirection -Anemometer• Airhumidity -Barometer• Atmosphericpressure -Hygrometer• Amountofrainfall -Weathervane• Windspeed -Raingauge

32. Answer.Atmosphereandweather

Whatisthedifferencebetweenweatherandclimate?

33. Answer.Atmosphereandweather2Whatisthenameoftheplacewheremeteorologicalinstrumentscanbefound?

34. Reflect.PressureandclimateWhyisn'ttheexpression:"Theclimateisgoodtoday"correct?

35. Reflect.PressureandclimateIstheairpressureatthetopofamountainhigherorlowerthantheairpressureatsealevel?Explainyouranswer.

36. Reflect.PressureandclimateWhatistherelationshipbetweenatmosphericpressureandaltitude?

37. Reflect.PressureandclimateWhyisthejunglemorehumidthanthedesert?6.ATMOSPHERICPHENOMENA6.1.Wind Windisthemovementofairproducedbythedifferencesinairpressurebetweentwodifferentplaces.ThesedifferencesoccurbecausetheheatingoftheEarth'ssurfaceisuneven. Winds have different names depending on their strength. They include breeze,wind,stormandhurricane.Windspeedcanvaryfrom6km/htomorethan120km/hinthecaseofahurricaneBreezes Onasunnyday,thelandonthecoastheatstheairdirectlyaboveit.Thisairrisesleavinga space forair that isdirectlyabove thesea.This createsa seabreeze thatgoes

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fromseatoland. When night falls, the land cools faster than the sea. The sea retains its heat forlonger.Asaresult,theairovertheseaishotter,soitrises.Coldairfromthelandtakesitsplace.Thiscreatesalandbreezethatgoesfromlandtosea. Overareasofmountainsandvalleys,theheatingandcoolingoftheelevatedareasoflandexceedstheheatingandcoolingofthesurroundingairatthesamealtitude. Thesedifferencesintemperaturecausedifferencesinairpressure.Thiscanaffectthedirectionofthebreeze,whichoftenblowsfromthevalleytothemountainduringtheday,andfromthemountaintothevalleyatnight.6.2.Electricalphenomena Storms are heavy precipitation, usually rainfall, accompanied by thunder andlightning. Lightning is an electrical discharge within a cloud, or between a cloud and theground. ThunderisthesoundproducedbythelightningIfthestormisfarawayfromus,wefirstseethebrightlightofthelightning.Afterthis,wehear the thunder. The longer it takes for us to hear the thunder, the further away thestormis.6.3Clouds Atmosphericwatervapourcondensesatthetopofthetroposphere.Thesecooledwaterdropletscanformicecrystalsifthetemperatureisverylow. Cloudsformwhenthesewaterdropletsandicecrystalscometogether. Cloudsareclassifiedintofourbasictypes:cirrus,cumulus,stratusandnimbus. These four classifications are based on the shape of the clouds, their moisturecontentandthealtitudewheretheyareformed.6.4.Precipitation Waterdropletsandicecrystalsinthecloudsnaturallyjointogether.Whentheygetheavyenough,theyfalltoEarth. Fallingwaterdropletsoricecrystalsarecalledprecipitation.Thisprecipitationcantakemanyforms:rain,drizzle,hail,sleetorsnow.Activities

38. Putinorder.PrecipitationPuttheprocessofprecipiationinthecorrectorder:

I. -TheaircoolsII. -ItrainsIII. -ThewatervapourcondensesandformcloudsIV. -Humidandrisesinthemountains

39. Choose.Atmosphericphenomena

Matcheachphenomenonwith itsdescription: lightening,precipitation,wind, stormandcloud-Movementofairfromoneplacetoanotherbecauseofdifferencesinthepressurebetween-WaterdropletsandicecrystalsthatfallfromcloudstotheEarth'ssurface.-Atmosphericwatervapourthatcondensesinatthetopofthetroposphere.- Electrical discharge within a cloud or between a cloud and the ground. Intenseprecipitation,usuallyrain,accompaniedbylightening

40. Answer.AtmosphericphenomenaWhatiswind?Explaintheprocessbywhichseaandlandbreezesoccur.

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41. Answer.AtmosphericphenomenaDoseabreezesmovefromtheseatothecoast,ortheotherwayaround?Whataboutland

42. Answer.AtmosphericphenomenaHowarecloudsformed?

43. Answer.AtmosphericphenomenaWhatisthedifferencebetweenatornadoandahurricane?

44. Reflect.PrecipitationandstormsWhatistherelationshipbetweenwindandatmosphericpressure?

45. Reflect.PrecipitationandstormsWhatisthedifferencebetweenthunderandlightening?

46. Reflect.PrecipitationandstormsWhatarethefourbasictypesofcloud?

47. Reflect.PrecipitationandstormsWhatcausesprecipitation?Whatarethedifferenttypesofprecipitation?WEATHERMAPSAnticyclonesandcyclones TheatmosphericpressureisnotthesameatallpointsontheEarth'ssurface. Weathermapsshow,amongstotherthings,theatmosphericpressure. Onweathermaps,areaswiththesameatmosphericpressureareconnectedwithalinecalledanisobar. Thepatternsmadebytheselinesshowusareasofcyclonesandanticyclones. Cyclonesareareasoflowpressureandanticyclonesareareasofhighpressure.

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OntheEarth'ssurface,theseareasofpressurevary.Thisvariationproducesmovementsintheatmosphereandcauseswind.

Weathermaps Weathermaps show the stateofthe atmosphere over a large area at aspecific given time. They use symbols torepresent cloud cover, rainfall,temperatures and win direction andstrength. Meteorologists are people whostudy the weather. They use data fromweather stations and photos fromsatellitestocreateweathermaps. Weather forecasts arepredictionsofthestateoftheatmosphereataspecificgiventime.Activities

48. Look.IsobarsLookattheisobarmapandanswerthefollowingquestions:I. Whichsymbolsrepresentanticyclones?Wherearetheylocatedonthemap?

II. Accordingtothemap,whatistheweatherlikeontheIberianPeninsula?Howdoyou

know?

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III. Whereonthemapisrainexpected?