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TeamfromlandscapearchitectureclassXTeamMembers：EnvironmentalProtectionOurtopicWhatdoyouknowaboutgreenhouseeffect?Globalwarming?Risingsealevels?Theimpactontheearth?Outline•Greenhouseeffect•Globalwarming•RisingsealevelsGreenhouseeffectWhatisthegreenhouseeffect?Onasunnywinterday,youparkyourcarinthesun,lockit,andgocruisethelocalshoppingmallforacoupleofhours.Whenyoucomebacklaterandgetintoyourcar,whatdoyounotice?Istheinteriorofthecarhotorcold?Howdoesthetemperatureinsideofyourcarcomparetothetemperatureoutside?Ifyouhaveeverbeeninsideofagreenhouse,especiallywhenthesunisout,whathaveyouobserved?Itisdefinitelywarm,andusuallytheairismoist.Agreenhouseiscommonlywarmerthantheoutsideairbecauseagreenhousehastheabilitytotrapheatinsideofit.Thisphenomenoniscalledthegreenhouseeffect.GreenhouseeffectTheheatcausedbyinfraredradiationisabsorbedbygreenhousegasessuchaswatervapor,carbondioxide,ozoneandmethane,whichslowsitsescapefromtheatmosphere.Althoughgreenhousegasesmakeuponlyabout1percentoftheEarth'satmosphere,theyregulateourclimatebytrappingheatandholdingitinakindofwarm-airblanketthatsurroundstheplanet.Lifeontheearthdependsonenergyfromthesun.About30percentofthesunlightthatbeamstowardEarthisdeflectedbytheouteratmosphereandscatteredbackintospace.Therestreachestheplanet'ssurfaceandisreflectedupwardagainasatypeofslow-movingenergycalledinfraredradiation.GreenhouseeffectThegreenhouseeffectisanaturallyoccurringprocessthataidsinheatingtheEarth'ssurfaceandatmosphere.Itresultsfromthefactthatcertainatmosphericgases,suchascarbondioxide,watervapor,andmethane,areabletochangetheenergybalanceoftheplanetbyabsorbinglongwaveradiationemittedfromtheEarth'ssurface.WithoutthegreenhouseeffectlifeonthisplanetwouldprobablynotexistastheaveragetemperatureoftheEarthwouldbeachilly-18°Celsius,ratherthanthepresent15°CelsiusGreenhouseeffectHowDoHumansContributetotheGreenhouseEffect?WhilethegreenhouseeffectisanessentialenvironmentalprerequisiteforlifeonEarth,therereallycanbetoomuchofagoodthing.Theproblemsbeginwhenhumanactivitiesdistortandacceleratethenaturalprocessbycreatingmoregreenhousegasesintheatmospherethanarenecessarytowarmtheplanettoanidealtemperature.GreenhouseeffectBurningnaturalgas,coalandoil-includinggasolineforautomobileengines-raisesthelevelofcarbondioxideintheatmosphere.Somefarmingpracticesandland-usechangesincreasethelevelsofmethaneandnitrousoxide.GreenhouseeffectDeforestationalsocontributestoglobalwarming.Treesusecarbondioxideandgiveoffoxygeninitsplace,whichhelpstocreatetheoptimalbalanceofgasesintheatmosphere.Asmoreforestsareloggedfortimberorcutdowntomakewayforfarming,however,therearefewertreestoperformthiscriticalfunction..Manyfactoriesproducelong-lastingindustrialgasesthatdonotoccurnaturally,yetcontributesignificantlytotheenhancedgreenhouseeffectandglobalwarmingthatiscurrentlyunderway.GreenhouseeffectUltimately,moregreenhousegasesmeansmoreinfraredradiationtrappedandheld,whichgraduallyincreasesthetemperatureoftheEarth'ssurfaceandtheairintheloweratmosphere.Populationgrowthisanotherfactoringlobalwarming,becauseasmorepeopleusefossilfuelsforheat,transportationandmanufacturingthelevelofgreenhousegasescontinuestoincrease.Asmorefarmingoccurstofeedmillionsofnewpeople,moregreenhousegasesentertheatmosphereGlobalwarmingWhatistheglobalwarming?GlobalwarmingisthecontinuingriseintheaveragetemperatureofEarth'satmosphereandoceans.GlobalwarmingWhatistheimpactofglobalwarming?SuchanunusuallyrapidrateofchangewouldaffectfundamentalEarthsystemsuponwhichourverylivesdepend(R)Cincludingoceancirculationandthehydrological,carbonandnutrientcycles.Itwoulddisruptthenaturalandmanagedecosystemsthatprovideuswithwater,foodandfiber.Itwouldaddtoexistingenvironmentalstressessuchasdesertification,decliningwaterquality,stratosphericozonedepletion,urbanairpollutionanddeforestation.______”Howwillglobalwarmingaffectourworld”(thebookletofPICC)Reference:(theleftsidepicture)4.Morefloods(therightsidepicture)Floodingrepresentsoneofthemostdangeroushazardstohumansettlementsandisoneofthemostpotentiallymomentousimpactsofglobalwarming.Globalwarming5.Desertification6.TsunamisAlthoughglobalwarmingdoesnotdirectlyinfluencetheformationoftsunamis,theycanbegeneratedbyeventsthatarebroughtaboutbyanamplificationoftheplanet’stemperature.Globalwarming7.ColdWavesMorethan150peoplelosttheirlivesduringthe2009to2010winterafterrecordlowtemperaturesandabundantsnowfallcauseddisruptiontomuchofEurope–whichdoesn'ttakeintoaccountthemanythousandsmoreexcesswinterdeathsthatwerecausedindirectly.ItwastheUK’scoldestwinterforthreedecades.8.IncreasedvolcanicactivityMeltingglaciationscanusherinnew,morefrequentandmoredangerousepisode