climate-change-全球变暖PP课件

climatechange全球变暖1、纪律是管理关系的形式。——阿法纳西耶夫2、改革如果不讲纪律，就难以成功。3、道德行为训练，不是通过语言影响，而是让儿童练习良好道德行为，克服懒惰、轻率、不守纪律、颓废等不良行为。4、学校没有纪律便如磨房里没有水。——夸美纽斯5、教导儿童服从真理、服从集体，养成儿童自觉的纪律性，这是儿童道德教育最重要的部分。——陈鹤琴climatechange全球变暖climatechange全球变暖1、纪律是管理关系的形式。——阿法纳西耶夫2、改革如果不讲纪律，就难以成功。3、道德行为训练，不是通过语言影响，而是让儿童练习良好道德行为，克服懒惰、轻率、不守纪律、颓废等不良行为。4、学校没有纪律便如磨房里没有水。——夸美纽斯5、教导儿童服从真理、服从集体，养成儿童自觉的纪律性，这是儿童道德教育最重要的部分。——陈鹤琴ClimateChangeandSea-levelRise1ClimateChangeinthepastObservationMeasurementTemperatureChange2HumanandNaturalDriversofClimateChangeMethodTheMainRadiativeForcingMethodChangesintheatmosphericabundanceofgreenhousegasesandaerosols,insolarradiationandinlandsurfacepropertiesaltertheenergybalanceoftheclimatesystem.Thesechangesareexpressedintermsofradiativeforcing,whichisusedtocomparehowarangeofhumanandnaturalfactorsdrivewarmingorcoolinginfluencesonglobalclimate.

TheMainRadiativeForcingGlobalatmosphericconcentrationsofcarbondioxide,methaneandnitrousoxidehaveincreasedmarkedlyasaresultofhumanactivitiessince1750andnowfarexceedpre-industrialvaluesdeterminedfromicecoresspanningmanythousandsofyears.CarbonDioxideCarbondioxideisthemostimportantanthropogenicgreenhousegas.Theglobalatmosphericconcentrationofcarbondioxidehasincreasedfromapre-industrialvalueofabout280ppmto379ppmin2005.MethaneTheglobalatmosphericconcentrationofmethanehasincreasedfromapre-industrialvalueofabout715ppbto1732ppbintheearly1990s,andis1774ppbin2005.NitrousOxideTheglobalatmosphericnitrousoxideconcentrationincreasedfromapre-industrialvalueofabout270ppbto319ppbin2005.AnthropogeniccontributionsThecombinedradiativeforcingduetoincreasesincarbondioxide,methane,andnitrousoxideis+2.30[+2.07to+2.53]wm-2.SolarIrradianceChangesinsolarirradiancesince1750areestimatedtocausearadiativeforcingof+0.12[+0.06to+0.30]wm-2TheunderstandingofanthropogenicwarmingandcoolinginfluencesonclimatehasimprovedsincetheThirdAssessmentReport(TAR),leadingtoveryhighconfidencethatthegloballyaveragedneteffectofhumanactivitiessince1750hasbeenoneofwarming,witharadiativeforcingof+1.6[+0.6to+2.4]wm-2.3

ProjectionsofFutureChangesinClimateandSeaLevelRiseSRESFutureGreenhouseGasEmissionsFutureChangesinClimateSeaLevelRiseSRESContinuedgreenhousegasemissionsatorabovecurrentrateswouldcausefurtherwarmingandinducemanychangesintheglobalclimatesystemduringthe21stcenturythatwouldverylikelybelargerthanthoseobservedduringthe20thcentury.SRES,thatis,theIPCCSpecialReportonEmissionScenarios.Therearesixscenariogroupsthatshouldbeconsideredequallysoundthatspanawiderangeofuncertainty,asrequiredbytheTermsofConference.Theseencompassfourcombinationsofdemographicchange,socialandeconomicdevelopment,andbroadtechnologicaldevelopments,correspondingtothefourfamilies(A1,A2,B1,B2),eachwithanillustrative“marker”scenario.A1.TheA1storylineandscenariofamilydescribesafutureworldofveryrapideconomicgrowth,globalpopulationthatpeaksinmid-centuryanddeclinesthereafter,andtherapidintroductionofnewandmoreefficienttechnologies.Majorunderlyingthemesareconvergenceamongregions,capacitybuildingandincreasedculturalandsocialinteractions,withasubstantialreductioninregionaldifferencesinpercapitaincome.ThethreeA1groupsaredistinguishedbytheirtechnologicalemphasis:fossilintensive(A1FI),non-fossilenergysources(A1T),orabalanceacrossallsources(A1B)(wherebalancedisdefinedasnotrelyingtooheavilyononeparticularenergysource,ontheassumptionthatsimilarimprovementratesapplytoallenergysupplyandenduse.A2.TheA2storylineandscenariofamilydescribesaveryheterogeneousworld.Theunderlyingthemeisselfrelianceandpreservationoflocalidentities.Fertilitypatternsacrossregionsconvergeveryslowly,whichresultsincontinuouslyincreasingpopulation.Economicdevelopmentisprimarilyregionallyorientedandpercapitaeconomicgrowthandtechnologicalchangemorefragmentedandslowerthanotherstorylines.B1.TheB1storylineandscenariofamilydescribesaconvergentworldwiththesameglobalpopulation,thatpeaksinmid-centuryanddeclinesthereafter,asintheA1storyline,butwithrapidchangeineconomicstructurestowardaserviceandinformationeconomy,withreductionsinmaterialintensityandtheintroductionofcleanandresourceefficienttechnologies.Theemphasisisonglobalsolutionstoeconomic,socialandenvironmentalsustainability,includingimprovedequity,butwithoutadditionalclimateinitiatives.B2.TheB2storylineandscenariofamilydescribesaworldinwhichtheemphasisisonlocalsolutionstoeconomic,socialandenvironmentalsustainability.Itisaworldwithcontinuouslyincreasingglobalpopulation,ataratelowerthanA2,intermediatelevelsofeconomicdevelopment,andlessrapidandmorediversetechnologicalchangethanintheB1andA1storylines.Whilethescenarioisalsoorientedtowardsenvironmentalprotectionandsocialequity,itfocusesonlocalandregionallevels.FutureGreenhouseGasEmissionsTotalcumulativeSREScarbonemissionsfromallsourcesthrough2100rangefromapproximately770Gtctoapproximately2540Gtc.FutureChangesinClimateAdvancesinclimatechangemodellingnowenablebestestimatesandlikelyassesseduncertaintyrangestobegivenforprojectedwarmingfordifferentemissionscenarios.Continuedgreenhousegasemissionsatorabovecurrentrateswouldcausefurtherwarmingandinducemanychangesintheglobalclimatesystemduringthe21stcenturythatwouldverylikelybelargerthanthoseobservedduringthe20thcentury.BestestimatesandlikelyrangesforgloballyaveragesurfaceairwarmingforsixSRESemissionsmarkerscenariosareshowninTable1.Forexample,thebestestimateforthelowscenario(B1)is1.8°C(likelyrangeis1.1°Cto2.9°C),andthebestestimateforthehighscenario(A1FI)is4.0°C(likelyrangeis2.4°Cto6.4°C).SeaLevelRiseGlobalwarmingcancausetheriseinsealevel.BestestimatesandlikelyrangesfortheriseinsealevelareshowninTable1.4MangroveResponsetoProjectedRelativeSea-levelRiseTherelationshipbetweensea-levelriseandthelossesofcoastalmangrovesThreegeneralscenariosformangroveresponsetorelativesea-levelriseTherelationshipbetweensea-levelriseandthelossesofcoastalmangrovesGlobalsea-levelriseisoneofthemorecertainoutcomesofglobalwarming,itisalreadylikelytakingplace,andseveralclimatemodelsprojectacceleratedrateofsea-levelriseovercomingdecades.Relativesea-levelriseisamajorfactorcontributingtorecentlossesandprojectedfuturereductionsintheareaofvaluedcoastalhabitats,includingmangrovesandothertidalwetlands,withconcomitantincreasedthreattohumansafetyandshorelinedevelopmentfromcoastalhazards.Threegeneralscenariosformangroveresponsetorelativesea-levelriseHereitcanbeinferredthattheforceofsea-levelriserelativetothemangrovesurfaceiscausinglandwardmigration.Therearethreegeneralscenariosformangroveresponsetorelativesea-levelrise,givenalandscape-levelscaleandtimeperiodofdecadesorlonger.Nochangeinrelativesea-levelWhensea-levelisnotchangingrelativetothemangrovesurface,mangroveelevation;salinity;frequency,period,anddepthofinundation;andotherfactorsthatdetermineifamangrovecommunitycanpersistatalocationwillremainrelativelyconstantandthemangrovemarginswillremaininthesamelocation.Relativesea-levelloweringWhensea-levelisdroppingrelativetothemangrovesurface,thisforcesthemangrovemarginstomigrateseaward.Themangrovemayalsoexpandlaterally,displacingothercoastalhabitats,ifareasadjacenttothemangrove,whicharecurrentlyatalowerelevationthanthemangrovesurface,develophydrologicconditionssuitableformangroveestablishment.Relativesea-levelrisingIfsea-levelisrisingrelativetothemangrovesurface,themangrove’sseawardandlandwardmarginsretreatlandward,themangrovespecieszonesmigrateinlandastheymaintaintheirpreferredperiod,frequencyanddepthofinundation.Themangrovemayalsoexpandlaterallyifareasadjacenttot