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1、ClassoneMariaglobalwarmingcontentWecandoEffectDefinitionCauseDefinitionwhatisglobalwarming?GlobalwarmingistheobservedandprojectedincreasesintheaveragetemperatureofEarth'satmosphereandoceans.presentsituationTheEarth'saveragetemperatureroseabout0.6°Celsius(1.1°Fahrenheit)inthe20thcenturypredi
2、ctionAccordingtodifferentassumptionaboutthefuturebehaviourofmankind,aprojectionofcurrenttrendsasrepresentedbyanumberofdifferentscenarios givestemperatureincreasesofabout3°to5° C(5° to9° Fahrenheit)bytheyear2100orsoonafterwards.GlobalWarmingCauses:ATop5ListCarbondioxideemissionsfromfossilfue
3、lburningpowerplantsCarbondioxideemissionsfromburninggasolinefortransportationDeforestation,especiallytropicalforestsforwoodpulp,andfarmlandIncreaseinusageofchemicalfertilizersoncroplandsMethaneemissionsfromanimals ,agriculturesuchasricepaddies,andfromArcticseabedsCarbondioxideemissionsfromf
4、ossilfuelburningpowerplantsEveryday,moreelectricgadgetsfloodthemarket,andwithoutwidespreadalternativeenergysources,wearehighlydependentonburningcoalforourpersonalandcommercialelectricalsupply.CarbondioxideemissionsfromburninggasolinefortransportationWithourpopulationgrowingatanalarmingrate,
5、thedemandformorecarsandconsumergoodsmeansthatweareincreasingtheuseoffossilfuelsfortransportationandmanufacturing.Ourconsumptionisoutpacingourdiscoveriesofwaystomitigatetheeffects.Methaneemissionsfromanimals ,agriculturesuchasricepaddies,andfromArcticseabedsMethaneisanotherextremelypotentgre
6、enhousegas,rankingrightbehindCO2.Whenorganicmatterisbrokendownbybacteriaunderoxygen-starvedconditionsasinricepaddies,methaneisproduced.Deforestation ,especiallytropicalforestsforwood,pulp,andfarmlandTheuseofforestsforfuelisonecauseofdeforestation. Forestsremoveandstorecarbondioxidefromtheat
7、mosphere,andthisdeforestationreleaseslargeamountsofcarbon,aswellasreducingtheamountofcarboncaptureontheplanet.IncreaseinusageofchemicalfertilizersoncroplandsInthelasthalfofthe20thcentury,theuseof chemicalfertilzers hasrisendramatically. Thehighrateofappl
