初中英语演讲稿编辑精选.docx

初中英语演讲稿

第一篇：初中英语演讲稿Atfirst,youmustunderstandthemeaningofclimatechange.Itmeansanylong-termsignificantchangeintheaverageweather,whichmayincludeaveragetemperature,precipitation,windpatternsandsoon.Forexample,Australiaisexperiencingrapidclimatechange.Sincethemiddleofthetwentiethcentury,Australiantemperatureshaverisenbyaboutaverageonetemperaturedegreewithanincreaseinthefrequencyofheatwavesandadecreaseinthenumbersoffrostsandcolddays.Rainfallpatternshavealsochanged,whichmeansthatthenorthwesthasseenanincreaseinrainfalloverthelastfiftyyearswhilemuchofeasternAustraliaandthefarsouthwesthaveexperiencedadecline.Fromthisexample,itindicatesclimatechangethatisoccurringtodayhasspedup,andaffectslong-termweather.TheEarth’sclimateislargelyaffectedbyhowmuchheatisstoredintheatmosphere.Furthermore,theclimatechangeiscausedbydynamicprocessonEarth,externalforcesincludingvariationsinsunlightintensity,andmorerecentlybyhumanactivities.Themostimportantreasonofclimatechangeiscausedbyhumans,becausehumansproducealotofcarbondioxideintotheair.Thiscarbondioxideemitsfromfossilfuel,aerosols,cementmanufacture,landuse,animalagricultureanddeforestation.Forexample,treescantakeincarbondioxidetoproduceoxygenbyphotosynthesis.Ifpeoplecutmanytreesformakingfurniture,paper,orsellwoodtomakemoney,thereismuchmorecarbondioxideintheair.Beginningwiththeindustrialrevolutioninthenineteenthcenturyandacceleratingeversince,thehumanconsumptionoffossilfuelshasraisedcarbondioxidelevelsrapidly.Itmeansthatcarbondioxidelevelsaresubstantiallyhighernowthanbefore.Ontheotherhand,duringtheprocedureofmanufacturingcement,whichisusedinbuildings,significantlymorecarbondioxideisproduced.Whilepeopleimprovetheirlivingstandard,theycauseclimatechange.Whenpeopleburncoal,oil,andgasforourelectricity,carbondioxideisproduced.Whenpeopleburnfossilfueltomovevehicles,carbondioxideisalsoproduced.Thesesortsofexamplesindicatethathumansaretherealculprit.Theydonotconsidertheconsequence,whiletheyenjoyproducingeverythingtheywant.Itisnotjustman-madepollutionof