Environmental-Protection(环境保护演讲PPT).ppt 33页

'TeamfromlandscapearchitectureclassXTeamMembers：EnvironmentalProtection OurtopicWhatdoyouknowaboutgreenhouseeffect?Globalwarming?Risingsealevels?Theimpactontheearth? OutlineGreenhouseeffectGlobalwarmingRisingsealevels GreenhouseeffectWhatisthegreenhouseeffect?Onasunnywinterday,youparkyourcarinthesun,lockit,andgocruisethelocalshoppingmallforacoupleofhours.Whenyoucomebacklaterandgetintoyourcar,whatdoyounotice?Istheinteriorofthecarhotorcold?Howdoesthetemperatureinsideofyourcarcomparetothetemperatureoutside?Ifyouhaveeverbeeninsideofagreenhouse,especiallywhenthesunisout,whathaveyouobserved?Itisdefinitelywarm,andusuallytheairismoist.Agreenhouseiscommonlywarmerthantheoutsideairbecauseagreenhousehastheabilitytotrapheatinsideofit.Thisphenomenoniscalledthegreenhouseeffect. GreenhouseeffectTheheatcausedbyinfraredradiationisabsorbedby"greenhousegases"suchaswatervapor,carbondioxide,ozoneandmethane,whichslowsitsescapefromtheatmosphere.Althoughgreenhousegasesmakeuponlyabout1percentoftheEarth"satmosphere,theyregulateourclimatebytrappingheatandholdingitinakindofwarm-airblanketthatsurroundstheplanet.Lifeontheearthdependsonenergyfromthesun.About30percentofthesunlightthatbeamstowardEarthisdeflectedbytheouteratmosphereandscatteredbackintospace.Therestreachestheplanet"ssurfaceandisreflectedupwardagainasatypeofslow-movingenergycalledinfraredradiation. GreenhouseeffectThegreenhouseeffectisanaturallyoccurringprocessthataidsinheatingtheEarth"ssurfaceandatmosphere.Itresultsfromthefactthatcertainatmosphericgases,suchascarbondioxide,watervapor,andmethane,areabletochangetheenergybalanceoftheplanetbyabsorbinglongwaveradiationemittedfromtheEarth"ssurface.WithoutthegreenhouseeffectlifeonthisplanetwouldprobablynotexistastheaveragetemperatureoftheEarthwouldbeachilly-18°Celsius,ratherthanthepresent15°Celsius GreenhouseeffectHowDoHumansContributetotheGreenhouseEffect?WhilethegreenhouseeffectisanessentialenvironmentalprerequisiteforlifeonEarth,therereallycanbetoomuchofagoodthing.Theproblemsbeginwhenhumanactivitiesdistortandacceleratethenaturalprocessbycreatingmoregreenhousegasesintheatmospherethanarenecessarytowarmtheplanettoanidealtemperature. GreenhouseeffectBurningnaturalgas,coalandoil-includinggasolineforautomobileengines-raisesthelevelofcarbondioxideintheatmosphere.Somefarmingpracticesandland-usechangesincreasethelevelsofmethaneandnitrousoxide. GreenhouseeffectDeforestationalsocontributestoglobalwarming.Treesusecarbondioxideandgiveoffoxygeninitsplace,whichhelpstocreatetheoptimalbalanceofgasesintheatmosphere.Asmoreforestsareloggedfortimberorcutdowntomakewayforfarming,however,therearefewertreestoperformthiscriticalfunction..Manyfactoriesproducelong-lastingindustrialgasesthatdonotoccurnaturally,yetcontributesignificantlytotheenhancedgreenhouseeffectand"globalwarming"thatiscurrentlyunderway. GreenhouseeffectUltimately,moregreenhousegasesmeansmoreinfraredradiationtrappedandheld,whichgraduallyincreasesthetemperatureoftheEarth"ssurfaceandtheairintheloweratmosphere.Populationgrowthisanotherfactoringlobalwarming,becauseasmorepeopleusefossilfuelsforheat,transportationandmanufacturingthelevelofgreenhousegasescontinuestoincrease.Asmorefarmingoccurstofeedmillionsofnewpeople,moregreenhousegasesentertheatmosphere GlobalwarmingWhatistheglobalwarming?GlobalwarmingisthecontinuingriseintheaveragetemperatureofEarth"satmosphereandoceans. GlobalwarmingWhatistheimpactofglobalwarming?SuchanunusuallyrapidrateofchangewouldaffectfundamentalEarthsystemsuponwhichourverylivesdepend(R)Cincludingoceancirculationandthehydrological,carbonandnutrientcycles.Itwoulddisruptthenaturalandmanagedecosystemsthatprovideuswithwater,foodandfiber.Itwouldaddtoexistingenvironmentalstressessuchasdesertification,decliningwaterquality,stratosphericozonedepletion,urbanairpollutionanddeforestation.______”Howwillglobalwarmingaffectourworld”(thebookletofPICC)Reference:http://www.environmentalgraffiti.comhttp://www.ipcc.ch/ Globalwarming1.SpreadofdiseaseAsnortherncountrieswarm,diseasecarryinginsectsmigratenorth,bringingplagueanddiseasewiththem.Indeedsomescientistsbelievethatinsomecountries,thankstoglobalwarming,malariahasnotbeenfullyeradicated.2.Increasedprobabilityandintensityofdroughtsandheatwaves Globalwarming3.PolaricecapsmeltingTheicecapsmeltingisafour-prongeddanger.(theleftsidepicture)4.Morefloods(therightsidepicture)Floodingrepresentsoneofthemostdangeroushazardstohumansettlementsandisoneofthemostpotentiallymomentousimpactsofglobalwarming. Globalwarming5.Desertification6.TsunamisAlthoughglobalwarmingdoesnotdirectlyinfluencetheformationoftsunamis,theycanbegeneratedbyeventsthatarebroughtaboutbyanamplificationoftheplanet’stemperature. Globalwarming7.ColdWavesMorethan150peoplelosttheirlivesduringthe2009to2010winterafterrecordlowtemperaturesandabundantsnowfallcauseddisruptiontomuchofEurope–whichdoesn"ttakeintoaccountthemanythousandsmoreexcesswinterdeathsthatwerecausedindirectly.ItwastheUK’scoldestwinterforthreedecades.8.IncreasedvolcanicactivityMeltingglaciationscanusherinnew,morefrequentandmoredangerousepisodesofvolcanicactivity. Globalwarming9.LossofbiodiversityandanimalextinctionLossofhabitatforpolar-iceedgecommunitiessuchaspolarbearsisperhapsthemostobviousconsequenceofhavingawarmerclimate.10.Deathofoceanlife Globalwarming11.Warmerwatersandmorehurricanes12.EconomicconsequencesMostoftheeffectsofanthropogenicglobalwarmingwon’tbegood.Andtheseeffectsspellonethingforthecountriesoftheworld:economicconsequences.Hurricanescausebillionsofdollarsindamage,diseasescostmoneytotreatandcontrolandconflictsexacerbateallofthese Globalwarming13.FiresandwildfiresAstheplanetcontinuestowarm,dryareasoflandthatarealreadysusceptibletowildfiresarelikelytoberavagedbyevenmorefrequentanddestructiveepisodes.In2007,morethan3,000firesbroughtdestructiontoSoutheasternEuropethankstoalongsummerthatcreatedaridandparchedconditions–asituationthatwouldbecomenormalasaconsequenceofthegreenhouseeffect.14.Destructivestormswarmeroceansmakeformoreextremeweatherincludingdevastatingstorms. Globalwarming15.DeathbysmogApowerfulcombinationofvehicularfumes,ground-levelozone,airborneindustrialpollutionandthestagnanthotairassociatedwithheatwaves,smogrepresentsanimmediateandchronichealththreattothoselivinginbuilt-upurbanareas.16.MoredangerousthunderstormsAconsequenceoftheincreasedamountsofhumidairgeneratedbyglobalwarmingisthatmorethunderstormswillbetriggered. Globalwarming17.AnimalattacksAnimalsthataredrivenfromtheirnaturalhabitatsornormalmigrationroutesbyenvironmentalfactorscouldeasilycomeintocontactwithhumansettlements,leadingtomanydeathsamonghumansandalreadyendangeredanimals.18.Diminishedfoodandwatersupplies RisingsealevelsWhatistherisingsealevels?RisingSeaLevelsisaglobalsealevelsrisingphenomenoncausedbythetemperatureeffectontheoceans,themeltingoficesheetsandglaciers,andchangesingroundwaterstorage. RisingsealevelsTheimpactofclimatechangeontheAntarcticPeninsulaisevidentinnewsatellitedata,USresearcherssay.ThecollapseoftheLarsenBiceshelfhasacceleratedtheflowofglaciersintothenearbyWeddellSeain2002.TheAntarcticPeninsulahasseensomeofthefastesttemperaturerisesonEarthinthelastfivedecades.ThescientistsusedavarietyofdatafromsatellitestotrackthespeedoftheglaciersbeforeandafterthecollapseofLarsenB.Inonestudy,TedScambosoftheNationalSnowandIceDataCenterinBoulder,US,analysedfiveimagestakenbytheLandsat7satellitebetweenJanuary2000andFebruary2003.TheanalysisrevealsthatfourglaciersflowingintothenowcollapsedsectionofLarsenBincreasedinspeedbybetweentwoandsixtimesoverthestudyperiod."IfanyonewaswaitingtofindoutwhetherAntarcticawouldrespondquicklytoclimatewarming,Ithinktheanswerisyes,"saidDrScambos. RisingsealevelsThesecondreport,byEricRignotoftheUSspaceagency"sJetPropulsionLaboratoryinPasadena,US,showedaneightfoldincreaseinthespeedofthreeglaciers,calledHektoria,GreenandEvans,between2000and2003.Twoothers,JorumandCrane,movedtwiceasquicklyatthebeginningof2003thantheydidin2000andnearlythreetimesasfastbytheendoftheyear."Thesetwopapersclearlyillustrate,forthefirsttime,therelationshipbetweeniceshelfcollapsescausedbyclimatewarming,andacceleratedglacierflow,"saidDrRignot.Theextraicepresumablytranslatesintohighersealevel.Buthowmuchthisisraisingtheleveloftheoceansisn"tknown. RisingsealevelsTheinfluenceofrisingsealevelsisveryserious,sealevelsrisingtotheharmofhumanenvironmentisshownas:thecoastallandareaofnarrow,furnitureofcoastalerosion,floodandfloodingcausedbytown,saltwaterintrusionandsoon.Aboutclimatechangereportfoundthatby2100thesealevelcouldrise1morhigher,atleastnotlessthan50centimeters.About10%oftheworld"spopulation(600million)inafloodedthedangerevenifitisthelowestwaterlevelrises. RisingsealevelsForexampleAccordingtothedevelopmenttrendandthesealevelrosesharply,theIndianOceanandthemaldivesinthePacificislandcountriesTuWaLuetcwillbesubmerged,Calcutta,dhakaandothercoastalcitieswillbedestroyed.CityofLondon,NewYork,andShanghaiwillbeforcedtocostbillionsofdollarsoffundsforfloodcontrol. RisingsealevelsTheleftoneisthearcticGreenland1992yearstheareaofthemeltingice.2002yearsisamongtheareaofthemeltingice.Rightistheareaofthemeltingicein2005.Sowewillhavetogotomaptheworld. RisingsealevelsIfGreenlandormeltingGreenlandandwestAntarcticaeachmeltinghalf,BeijingandShanghaiaresupposedtodisaster.AboveisafloodedareaofShanghai,therewillbe40millionpeopleaffected.Below,Beijingwillhaveaffectedmillionsofpeople. RisingsealevelsIfGreenlandormeltingGreenlandandwestAntarcticaeachhalfmeltedandtheworldwillbetherewillbemanycoastalcitywasunderwaterscene. RisingsealevelsTheIndianOceantsunamisite:Sea-levelrisesnotonlycoveredthecoastalland,butthetsunami,suchasMarinedisasters,thestormismorelikelytooccur,andthelossisbigger. RisingsealevelsTheUnitedStatesbeachesallhappenedmorethanasharksighting,maybeduetotheoffshorewarmingwaters,sealsapopulation,sharkfamilypeoplemorerantotheoffshoreareashunting. RisingsealevelsWhatcanwedo? Thanksforyourlistening!'