世界氣候變化Climate Change(溫室效應(yīng)Green House Effect)英文介紹

ClimateChange/GlobalWarmingDefinition(n.):achangeinglobalclimatepatternsapparentfromthemidtolate20thcenturyonwards,attributedlargelytotheincreasedlevelsofatmosphericcarbondioxideproducedbytheuseoffossilfuels.Itiscommonlyknownas“globalwarming”ContributingGasesWatervapor.Themostabundantgreenhousegas,butimportantly,itactsasafeedbacktotheclimate.Watervaporincreasesasgreenhousegasesdo;therefore,moreprecipitationleadstoevenmoreprecipitationandsoon.Carbondioxide(CO2).Aminorbutthemostimportantcomponentoftheatmosphere,carbondioxideisreleasedthroughnaturalprocessessuchasbreathingandvolcanoeruptionsandthroughhumanactivitiessuchasdeforestation,landusechanges,andburningfossilfuels.HumanshaveincreasedatmosphericCO2

concentrationbyathirdsincetheIndustrialRevolutionbegan.Methane.(MH4)Anaturalandhumancreatedhydrocarbongascausebythedecayofwastesinlandfills,agriculture(especiallyrice

cultivation),andmanurefromlivestock.Muchlessabundantintheatmosphere,butmore“powerful”thanCO2.Nitrousoxide(N2O).Apowerfulgreenhousegasproducedbysoilcultivationpractices,especiallytheuseofcommercialandorganicfertilizers,fossilfuelcombustion,nitricacidproduction,andbiomassburning.Chlorofluorocarbons(CFCs).Syntheticcompoundsofindustrialoriginusedinanumberofapplications.Emissionsareregulatedbyinternationalorganizationsbecauseoftheircontributiontodestroyingtheozonelayer.DefinitionsaccordingtoGlobalWarmingprocess1.ThesunemitsenergytowardstheEarth2.TheEarthreflectsaround30%oftheenergybackintospace;therestisabsorbedbyEarth’ssystem3.Becauseofgreenhousegasesintheatmosphere,onlysomeofthesun’senergyisallowedtoescapeimmediately—instead,thegasesstaywithintheatmosphere,bouncinginalldirections4.TheatmosphereisheatedupaslessandlessgasesareletoutintospaceandmoreenergyisabsorbedbyEarthProcessCausesWhathuman-relatedcausesarethere?DeforestationAgricultureFossilfuelburningAerosolgasesHuman-RelatedCausesDeforestationThecuttingoftreesdecreasestheamountofCO2thatcanbeabsorbedbyplantsforrecyclingAgriculture(fertilizerandmanure)Overeatingmeatandincorrectdietsoflivestockcreateextramanure,releasinglargeramountsofmethaneFossilfuelburning(Coal,oil,naturalgas,etc.)Exhaustfromcars,trucks,othervehiclesoftransportationPowerplantsburningfossilfuelsforelectricityEmitsCO2andCOAerosolgasesComesfromspraycans(i.e.bugspray),dust,otherparticulatesGasesblockthesun’slightfrombeingabsorbedbythesurface;instead,theparticlesabsorbthelightandkeepitintheair(lookatpriorpicture)Deforestation“Clearcutting”:cuttingdownaforestandremovingallplantstomakeacertainarea“clear”ofvegetationForestsareessentialforlife;theynotonlystoreCO2,butalsoreleaseoxygenintotheatmosphereTreesholdwaterinroots;preventsoilerosion;harborspeciesWhendestroyed,treesreleasestoredCO2intotheair;deforestationisresponsibleforabout20%ofallCO2emissionsbyhumansItisestimatedthatmorethan1.5billiontonsofCO2arereleasedintotheatmospherebecauseofcuttingandburningforestseveryyear—burningbeingatwo-foldpolluterOver30millionacresofforestaredestroyedeveryyear,mostlytoplantcropstofeedlivestock,buildinghouses,andfirewood;about50%ofworld’stropical(i.e.Amazon)forestshavebeendestroyedAgricultureIntheU.S.,20%ofCO2emissionscomefromagricultureIfwecountallthefuelandoilneededtoproducepesticidesortousetractorsandmachinery,thatnumberjumpsto25-30%ofU.S.CO2emissionsTheIPCC(IntergovernmentalPanelonClimateChange)statesthatagricultureisresponsibleforaround12%ofallCO2emissionsaroundtheworldClearingforests(deforestation)forfarmlandLivestockincreasemethaneemissions—accountforabout85%ofallmethaneemissionsGeneticallyModifiedOrganisms(GMOs)arefedtothelivestockinsteadofgrassandgrain,whichdisturbsthelivestock’sdigestivesystem;therefore,theyreleasemoregasFossilFuelburningWhenfossilfuelsareburnt,theyreleaseCO2—why?Becausefossilfuelsareanimalsandplants,whichstoreCO2intheirbodies;ifyouburnalivetree,itwillreleaseCO2aswellBurningfossilfuelsforelectricityaccountsforaround37%ofallCO2emissionsEverytonofcoalactuallyreleases2.86tonsofCO2—howisthispossible?Becausecoaliscompressedcarbon—whenthecarbongetsreleased,itcombineswiththeoxygentoformCO2Coalisalsothemostdangerousfuelbecauseitiscarbonthatisstoredinthegroundformillionsofyears—whenwereleaseit,weareaddingnewcarbonIntheU.S.,justunder50%ofelectricitycomesfromcoal“Cars,buses,andtrucksreleasepollutantsandgreenhousegasesthatpromotewarming,whileemittingfewaerosolsthatcounteractit.Incontrast,theindustrialandpowersectorsreleasemanyofthesamegases—withalargercontributiontoradiativeforcing—buttheyalsoemitsulfatesandotheraerosolsthatcausecoolingbyreflectinglightandalteringclouds…”

Radiativeforcing:thedifferenceinamountofenergythatisreceivedfromthesunandtheamountthatissentbacktospace

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TransportationandFossilFuelBurningHowcanwecurbfossilfuelburning?curb:restrain,holdbackBetterinsulation(protection,covering)inhousessoheat/colddoesnotseepoutMoreefficientcars;betterinfrastructure(i.e.highspeedtrains,bicyclingandwalkingpaths);usepublictransportationLessdependenceonoil,coal,andnaturalgas;transfertorenewablesourcesofenergyAerosolGasesMostaerosolparticlesreflectsunlight;however,dependingoncompositionandcolor,theycanalsoabsorbsunlightintheatmosphereBlackcarbonandsootfromcoalburningabsorbssunlight,thereforewarmingtheatmosphereSalt-basedaerosols(whicharelighterincolor)willreflectthesunlightAerosolscanalsocoverobjectsorreflectivesurfacessuchasice,thereforereversingtheroleoficeEffectsofGlobalWarmingSealevelrise/glaciermeltingExtremeweatherpatterns(hurricanes,droughts,floods,etc.)WildlifeendangermentAgriculturalproblemsandlackofresourcesSeaLevelRiseSeaLevelRiseOceanlevelshaverisenaround8inches(3.15cm)since1880;duetothis,theoceanhasbeenexpandingandcoveringareasoflandGlobalwarmingisthemaincauseofthesealevelrisingEvenifglobalwarmingemissionswereZEROin2016,thesealevelwouldstillrise1.2-2.6feetby2100—why?Iftrendscontinue,projectionsfor2100rangesfrom8inchincreaseto6.6feet(2meters)Risingsealevelscancausefurtherproblemssuchassoilerosion,moreintensestormsurges,permanentinundation,andsaltwaterintrusionSeaLevelRiseEffectsSoilerosionRisingsealevelsmeanswatercanreachfurtherinland,sweepingmoresoilawaywithitStormsurgesCoastalstormshavestrongwindsthatpushwaterinland;becausethesealevelishigher,itcanreachfurtherinlandanddestroymorepropertyandkillmorepeoplePermanentinundation(flooding)Someareaswouldbepermanentlyflooded(areassuchasFloridaandCalifornia,forexample);therefore,allhomes,apartments,andpropertywouldbedestroyedandcouldneverberebuiltSaltwaterinvasionSaltwatercangofurtherinland,seepingintoourdrinkingwaterresources(suchasaquifers),thereforeruiningitsdrinkabilityWaysofPrevention?Whataresomewaystoprepareourselvesandpreventstormwaterfromcominginland?Createlevees,buildwallsAddsandtobeachestoslowdownwaterProtectandmaintainislandsthatslowwatersdownMakingstructuresflood-proofAndofcourse,slowdownglobalwarmingExtremeWeatherPatternsRainstormshavebecomemoreintense;theNortheastU.S.gets67%morerainandsnowduringstrongstormsthanpreviously;onaverageintheentireU.S.,thenumberis20%;overallprecipitationhasincreased5%Morepowerfulhurricaneshavebeenoccurring;thestrengthofwindshasincreased70%since1970;morefrequenthurricanesduetooceantemperatureincrease(82degreesneededforahurricane)Highertemperaturesincreasedroughts;snowbeginstofallasraininstead,thereforeitevaporatesfasteranddoesnotgetsoakedupbythesoilFurtherWeatherIssuesDuetoanincreaseintemperature,manybugsandpestsaremovingfurthernorth,ruiningcropsandecosystemsAreasthatrelyonsnowforrecreationalactivitieswillhavetheireconomiesweakenedsignif