英语等级考试三级阅读考试样题练习2017年英语等级考试三级阅读考试样题练习读书谓已多，抚事知不足。以下是小编为大家搜索整理的2017年英语等级考试三级阅读考试样题练习，希望对正在关注的您有所帮助!更多精彩内容请及时关注我们应届毕业生考试网!练习:TheGreenhouseeffectandGlobalwarmingTheheart-trappingcapacityoftheatmosphereispopularlyknownasthe“greenhouseeffect”.Despitepubliccontroversysurroundingglobalwarming,thenaturalgreenhouseeffecthasbeenlongestablishedasfactinthescientificcommunity.Indeed,carbondioxide,andothergases,theearth’snaturalclimatewouldbeabout33℃coolerthanitis.Lifewouldhaveevolvedquitedifferentlyinsuchaclimate.Mostscientistsbelievethattherapidexpansionofagricultureandindustrialactivitiesoverthelastseveralhundredyearshavegeneratedsignificantincreasesincarbondioxideandmethaneintheatmosphere.However,expertsdisagreeaboutwhethersuchchangershavecausedtheincreaseofapproximately0.5℃intheearth’ssurfacetemperaturethathasbeendocumentedoverthepastcentury.Manyscientistscitethefactthat1997wasthewarmestyearonrecord,followingadecadeinwhich9ofthe11hottestyearsofthiscenturywerereported,asstrong,butcircumstantial,evidencethathumanactivitieshavealteredtheearth’sclimate.Otherexperts,however,believethistemperaturetrendisanaturalvariation.Alsodisputediswhetherprojectedworldpopulationgrowthtomorethan10billionpeoplebytheyear2100willresultinadoublingortriplingofatmosphericconcentrationsofcarbondioxide.Ifsuchabuildupoccurs,asmanyscientistspredict,globalsurfacetemperaturescouldincreasebyanywherefromaboutoneCelsiusdegreetoabout4Celsiusdegreesduringthenextcentury.Thehigherhalfofrangeinvolvestemperaturechangesoutsideofthoseexperiencedbyhumancivilizationssincetheendofthelasticeagesome10,000yearsago.Duringthelasticeage,averageglobaltemperatureswereonlyabout5Celsiusdegreescoolerthanthepresentperiod.AtemperatureincreaseofseveraldegreesCelsiuscouldresultinasealevelriserangingfromabout10cmtoabout1m.Asealevelriseofabout0.5mwouldbenoticeableprimarilyinthemostvulnerable,low-lyingislandsandcoastalareas.Largersealevelriseswouldresultinextensivefloodingoflowlandbeaches,wetlands,