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1、TeamfromlandscapearchitectureclassXTeamMembers：EnvironmentalProtectionOurtopicWhatdoyouknowaboutgreenhouseeffect?Globalwarming?Risingsealevels?Theimpactontheearth?OutlineGreenhouseeffectGlobalwarmingRisingsealevelsGreenhouseeffectWhatisthegreenhouseeffect?Onasunnywinterday,youparky
2、ourcarinthesun,lockit,andgocruisethelocalshoppingmallforacoupleofhours.Whenyoucomebacklaterandgetintoyourcar,whatdoyounotice?Istheinteriorofthecarhotorcold?Howdoesthetemperatureinsideofyourcarcomparetothetemperatureoutside?Ifyouhaveeverbeeninsideofagreenhouse,especiallywhenthesunis
3、out,whathaveyouobserved?Itisdefinitelywarm,andusuallytheairismoist.Agreenhouseiscommonlywarmerthantheoutsideairbecauseagreenhousehastheabilitytotrapheatinsideofit.Thisphenomenoniscalledthegreenhouseeffect.GreenhouseeffectTheheatcausedbyinfraredradiationisabsorbedby"greenhousegases"
4、suchaswatervapor,carbondioxide,ozoneandmethane,whichslowsitsescapefromtheatmosphere.Althoughgreenhousegasesmakeuponlyabout1percentoftheEarth'satmosphere,theyregulateourclimatebytrappingheatandholdingitinakindofwarm-airblanketthatsurroundstheplanet.Lifeontheearthdependsonenergyfromt
5、hesun.About30percentofthesunlightthatbeamstowardEarthisdeflectedbytheouteratmosphereandscatteredbackintospace.Therestreachestheplanet'ssurfaceandisreflectedupwardagainasatypeofslow-movingenergycalledinfraredradiation.GreenhouseeffectThegreenhouseeffectisanaturallyoccurringprocessth
6、ataidsinheatingtheEarth'ssurfaceandatmosphere.Itresultsfromthefactthatcertainatmosphericgases,suchascarbondioxide,watervapor,andmethane,areabletochangetheenergybalanceoftheplanetbyabsorbinglongwaveradiationemittedfromtheEarth'ssurface.Withoutthegreenhouseeffectlifeonthisplanetwould
7、probablynotexistastheaveragetemperatureoftheEarthwouldbeachilly-18°Celsius,ratherthanthepresent15°CelsiusGreenhouseeffectHowDoHumansContributetotheGreenhouseEffect?WhilethegreenhouseeffectisanessentialenvironmentalprerequisiteforlifeonEarth,therereallycanbetoomuchofagoodthing.Thepr
8、oblemsbeginwhenhumanactivi
