Unit-8-Focus-on-Global-Warming课文翻译综合教程二

Unit8FocusonGlobalWarmingJohnWeierTwenty-fiveyearsagoifyoumadeatriptothelocallibraryandperusedtheperiodicalsectionforarticlesonglobalwarming,you’dprobablyhavecomeupwithonlyafewabstractsfromhardcoresciencejournalsormaybeablurbinsomeesotericgeopoliticalmagazine.AsanInternetsearchonglobalwarmingnowattests,thesubjecthasbecomeasrootedinourpublicconsciousnessasMadonna2ormicrowavecooking.1Perhapsallthisattentionisdeserved.Withthepossibleexceptionofanotherworldwar,giantasteroid,oranincurableplague,globalwarmingmaybethesinglelargestthreattoourplanet.2Fordecadeshumanfactoriesandcarshavespewedbillionsoftonsofgreenhousegasesintotheatmosphere,andtheclimatehasbeguntoshowsomesignsofwarming.Manyseethisasaharbingerofwhatistocome.3Ifwedon’tcurbourgreenhousegasemissions,thenlow-lyingnationscouldbeawashinseawater,rainanddroughtpatternsacrosstheworldcouldchange,hurricanescouldbecomemorefrequent,andElNinoscouldbecomemoreintense.OurWarmingPlanetWhathasworriedmanypeoplenowisthatoverthepast250yearshumanshavebeenartificiallyraisingtheconcentrationofgreenhousegasesintheatmosphere.Ourfactories,powerplants,andcarsburncoalandgasolineandspitoutaseeminglyendlessstreamofcarbondioxide.Weproducemillionsofpoundsofmethanebyallowingourtrashtodecomposeinlandfillsandbybreedinglargeherdsofmethane-belchingcattle.Nitrogen-basedfertilizers,whichweuseonnearlyallourcrops,releaseunnaturalamountsofnitrogenoxideintotheatmosphere.Oncethesecarbon-basedgreenhousegasesgetintotheatmosphere,theystaytherefordecadesorlonger.AccordingtotheIntergovernmentalPanelonClimateChange(IPCC)sincetheindustrialrevolution,carbondioxidelevelshaveincreased31percentandmethanelevelshaveincreased151percent.Paleoclimatereadingstakenfromfossilrecordsshowthatthesegases,twoofthemostabundantgreenhousegases,areattheirhighestlevelsinthepast420,000years.ManyscientistsfearthattheincreasedconcentrationsofgreenhousegaseshavepreventedadditionalthermalradiationfromleavingtheEarth.Inessence,thesegasesaretrappingexcessheatintheEarth’satmosphereinmuchthesamewaythatawindshieldtrapssolarenergythatentersacar.4Muchoftheavailableclimatedataappeartobackthesefears.5TemperaturedatagatheredfrommanydifferentsourcesallacrosstheglobeshowthatthesurfacetemperatureoftheEarth,whichincludestheloweratmosphereandthesurfaceoftheocean,hasrisendramaticallyoverseveraldecades.Worldwidemeasurementsofsealevelshowariseof0.1to0.2metersoverthelastcentury.That’sanincreaseofroughly1℃every4,000years.Readingsgatheredfromglaciersrevealasteadyrecessionoftheworld’scontinentalglaciers.Takentogether,allofthesedatasuggestthatoverthelastcenturytheplanethasexperiencedthelargestincreaseinsurfacetemperatureNotsurprisingly,manyscientistsspeculatethatsuchchangesintheclimatewillprobablyresultinhotterdaysandfewercooldays.6AccordingtotheIPCC,landsurfaceareaswillincreaseintemperatureoverthesummermonthsmuchmorethantheocean.Themid-latitudetohigh-latituderegionsintheNorthernHemisphere—areassuchastheContinentalUnitedStates,Canada,andSiberia—willlikelywarmthemost.Theseregionscouldexceedmeanglobalwarmingbyasmuchas40percent.Asfarashumanhealthisconcerned,thosehithardestwillprobablyberesidentsofpoorercountriesthatdonothavethefundstofendagainstchangesinclimate.7TakingActionsFortunately,wecantakeactionstoslowdownglobalwarming.8Globalwarmingresultsprimarilyfromhumanactivitiesthatreleaseheat-trappinggasesandparticlesintotheair.Themostimportantcausesincludetheburningoffossilfuelssuchascoal,gas,andoil,anddeforestation.Toreducetheemissionofheat-trappinggaseslikecarbondioxide,methane,andnitrousoxides,wecancurbourconsumptionoffossilfuels,usetechnologiesthatreducetheamountofemissionswhereverpossible,andprotecttheforestsintheworld.Wecanalsodothingstomitigatetheimpactsofglobalwarmingandadapttothosemostlikelytooccur,9e.g.,throughcarefulplanningandotherstrategiesthatreduceourvulnerabilitytoglobalwarming.Butwecan’tstopthere.Wearealsoadvocatingpoliciesthatwillcombatglobal表明在过去一个世纪中，地球表面温度上升是近1000年里最快的。很自然地，许多科学家推测这种种气候变化很可能会导致天气越来越热，凉爽的日子越来越少。根据政府间气候变化问题专门研究小组的研究，地表夏季温度上升幅度将远大于海面温度的上升幅度。北半球中高纬度地——例如美国大陆地区，加拿大和西伯利亚地区——温度上升将最为剧烈。这些地区温度上升幅度将超过全球平均温度上升幅度的40%。就人类健康而言，那些受到最严重影响的将会是处于贫穷国家的居民，因为他们没有资金来抵御气候变化。在赤道地区,热量和降雨量少许增加就很可能会导致昆虫传播疾病的增加,例如疟疾。海岸地区与河道集中地区的降雨和飓风程度一旦变强，那将会造成更加严重的洪涝灾害和大批人员死亡。甚至海平面只是上升了一点，也会威胁到海拔很低的岛屿国家，例如马尔代夫。在全世界，更加炎热的夏天将导致更多人中暑，并且使那些体弱多病者，例如有心脏疾病的老人，失去生命。气温升高也会使近地面的臭氧含量增高，这些臭氧产生自工厂和汽车，并会使空气质量处于危险等级的日子越来越多，而且因为呼吸道疾病住院的人也会越来越多。采取行动吧幸运的是，我们可以多种采取措施来减缓全球变暖的进程。全球变暖很大一部分原因是人类活动排放出大量阻碍热量散失的气体和微粒子。其中最重要的原因是大量燃烧化石矿物燃料，例如煤炭、天然气和石油，还有就是滥砍滥伐。为了降低会阻碍热量散失的气体