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Authors:1JayBreidt,ColoradoStateUniversityStephenM.Ogle,ColoradoStateUniversityWendyPowers,MichiganStateUniversityCoeliHoover,USDAForestService
Contents:
8 UncertaintyAssessmentforQuantifyingGreenhouseGasSourcesandSinks...................8‐3 ComponentsandInputstoanEntity‐ScaleMonteCarloUncertaintyAssessment............8‐48.1
8.1.1 ParameterUncertainty..................................................................................................8‐58.1.2 SamplingMethodUncertainty....................................................................................8‐68.1.3 LargeDatasetUncertainty............................................................................................8‐98.1.4 ModelUncertainty.........................................................................................................8‐16
ResearchGaps...............................................................................................................................................8‐208.2Appendix8‐A:ExampleOutputFilefromFVSSamplingUncertaintyBootstrappingApplicationFVSBoot(asprovidedinGreggandHummel,2002)................................................................................8‐21Appendix8‐B:UncertaintyTables....................................................................................................................8‐22Chapter8References.............................................................................................................................................8‐55
SuggestedChapterCitation:Breidt,F.J.,Ogle,S.M.,Powers,W.,Hover,C.,2014.Chapter8:UncertaintyAssessmentforQuantifyingGreenhouseGasSourcesandSinks.InQuantifyingGreenhouseGasFluxesinAgricultureandForestry:MethodsforEntity‐ScaleInventory.TechnicalBulletinNumber1939.OfficeoftheChiefEconomist,U.S.DepartmentofAgriculture,Washington,DC.606pages.July2014.Eve,M.,D.Pape,M.Flugge,R.Steele,D.Man,M.Riley‐Gilbert,andS.Biggar,Eds.
USDAisanequalopportunityproviderandemployer.
1AllauthorsofChapters3,4,5,and6providedstrategicinputintheparametersintheuncertaintychapter.
Chapter 8
Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
Chapter 8: Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
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Acronyms,ChemicalFormulae,andUnitsCONUSSTATSGO ContinentalUnitedStatesSoilGeographicDatabaseDBH DiameteratbreastheightDNDC DeNitrification‐DeCompositionEPA U.S.EnvironmentalProtectionAgencyERS USDAEconomicResearchServiceFOFEM FirstOrderFireEffectsModelFVS ForestVegetationSimulatorGHG GreenhousegasIPCC IntergovernmentalPanelonClimateChangeNADP NationalAtmosphericDepositionProgramNARR NorthAmericanRegionalReanalysisNASS USDANationalAgriculturalStatisticsServiceNCEP NationalCentersforEnvironmentalPredictionNLCD NationalLandCoverDatabaseNOAA NationalOceanicandAtmosphericAdministrationNRCS USDANaturalResourcesConservationServiceNRI NationalResourceInventoryPDF ProbabilitydensityfunctionPRISM Parameter‐elevationRegressionsonIndependentSlopesModelSOC SoilorganiccarbonSSURGO SoilSurveyGeographicUSDA U.S.DepartmentofAgriculture
Chapter 8: Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
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8 UncertaintyAssessmentforQuantifyingGreenhouseGasSourcesandSinks
Quantifyingtheuncertaintyofgreenhousegas(GHG)emissionsandreductionsfromagricultureandforestrypracticesisanimportantaspectofdecision‐makingforfarmers,ranchersandforestlandownersastheuncertaintyrangeforeachGHGestimatecommunicatesourlevelofconfidencethattheestimatereflectstheactualbalanceofGHGexchangebetweenthebiosphereandtheatmosphere.Inparticular,afarm,ranch,orforestlandownermaybemoreinclinedtoinvestinmanagementpracticesthatreducenetGHGemissionsiftheuncertaintyrangeforanestimateislow,meaningthathigherconfidenceintheestimatesexists.Thischapterpresentstheapproachforaccountingfortheuncertaintyintheestimatednetemissionsbasedonthemethodspresentedinthisreport.2AMonteCarloapproachwasselectedasthemethodforestimatingtheuncertaintyaroundtheoutputsfromthemethodologiesinthisreportasitiscurrentlythemostcomprehensive,soundmethodavailabletoassesstheuncertaintyattheentityscale.Limitationsanddatagapsexist;however,asnewdatabecomeavailablethemethodcanbeimprovedovertime.ImplementationofaMonteCarloanalysisiscomplicatedandrequirestheuseofastatisticaltooltoproduceaprobabilitydensityfunction(PDF)3aroundtheGHGemissionsestimate.4FromthePDF,theuncertaintyestimatecanbederivedandreported.
2TheIPCCGoodPracticeGuidance(IPCC,2000)recommendstwoapproaches—Tier1andTier2—fordevelopingquantitativeestimatesofuncertaintyforemissionsestimatesforsourcecategories.TheTier1methoduseserrorpropagationequations.Theseequationscombinetheuncertaintyassociatedwiththeactivitydataandtheuncertaintyassociatedwiththeemission(orother)factors.Thisapproachisappropriatewhereemissions(orremovals)areestimatedastheproductofactivitydataandanemissionfactororasthesumofindividualsub‐sourcecategoryvalues.TheTier2methodutilizestheMonteCarloStochasticSimulationtechnique.Usingthistechnique,anestimateofemission(orremoval)foraparticularsourcecategoryisgeneratedmanytimesviaanuncertaintymodel,resultinginanapproximatePDFfortheestimate.Wheresufficientandreliableuncertaintydatafortheinputvariablesareavailable,theTier2methodisthepreferredoption.3TheintegralofaPDFoveragivenintervalofvaluesistheprobabilityforarandomvariabletotakeonsomevalueintheinterval.Thatis,thePDFisafunctiongivingprobability“densities”anditsintegralgivesprobabilities.AnarrowerPDFforanestimateindicatessmallervariancearoundthecentral/mostlikelyvalue,i.e.,ahigherprobabilityofthevaluetobeclosertothecentral/mostlikelyvalue.Theuncertaintyforsuchanestimateislower.4GiventhecomplexityofMonteCarloanalysisandthenecessityforatool,theapproachpresentedhereisnotintendedfordevelopmentbyalandowner,ratheritisintendedforuseindevelopingatoolthatalandownerwouldusetoassessuncertaintyestimates.
Chapter 8: Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
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UncertaintyinGHGemissionsestimationarisesbecauseofunknownorincompletelyknownfactorsassociatedwith:
Parameters–Duetolimitationsassociatedwithavailableinputdata(e.g.,activitydataandemissionfactors).
Samplingmethods–Duetoeithermeasurementerrorsduringsamplecollectionorpotentialvariationsinvaluesobtainedfromsampling(i.e.,whenthechosensampleisnotfullyrepresentativeoftheentirepopulation).
Largedatasets–Duetomeasurementserrorsduringdatacollection,andvariationsindatasetvaluesforagivensetofconditions.
Models–Duetoapproximationerrorsandestimationerrors.Approximationerrorarisesbecausethemodelisasimplificationoftherealsystem,whileestimationerrorarisesbecausethetheoreticalmodelisfittedusinglimiteddata.
Concepts–Thisiscloselyrelatedtomodelapproximationerrorandoccursbecausetheconceptualscopedoesnotcapturetheactual/realscopethuscreatingabias.Foranentity,thisconceptualizationuncertaintymayberelativelysmall.
Theapproachtoaddressuncertaintydoesnotaddressconceptualuncertaintybecauseitisexpectedtobesmallanddifficulttoquantify.Thischapteraddressesparameteruncertainty,samplinguncertainty,largedatasetuncertainty,andmodelapproximationuncertainty.WheredataarecurrentlyunavailableorincompleteforestablishingPDF’sandestimatinguncertainty,theauthorsprovideexpertjudgmentand/oraqualitativedescriptionofuncertaintyintheinterestsofmakingtheGHGmanagementmethodsastransparentandcompleteaspossible.Inthefuture,newdatacanbeusedtorefineandimprovetheestimationofuncertainty.
Inthischapter,Section8.1includesthecomponentsandinputstoanentity‐scaleMonteCarlouncertaintyassessment,andSection8.2highlightsresearchgaps.
ComponentsandInputstoanEntity‐ScaleMonteCarloUncertainty8.1Assessment
ToconductaMonteCarlouncertaintyanalysisforeachoftheGHGquantificationmethodsandresultingnetGHGemissions,informationisrequiredabouttheuncertaintyassociatedwith:(1)theinputvariables(i.e.,parameters);(2)samplingmethodsusedtoobtaindata;(3)existinglargedatasetsusedasdatasources;and(4)externalmodelsused.Ideally,thisinformationwouldconsistofspecificPDFs(e.g.,normal,triangular,uniform,beta).Alternatively,theuncertaintymightbe
MonteCarloAnalysisforAssessingUncertainty IntheMonteCarlomethod,uncertaininputs(parametersandotherdata)anduncertainmodel
structurearedescribedviaPDFs.ByrandomlyselectingfromeachofthesePDFs,andrunningtheselectedinputsthroughtheselectedmodel,anuncertaintymodeloutputisobtained.CombiningthesemodeloutputsacrossmanyrandomselectionsleadstoanapproximatePDFdescribinguncertaintyinthemodeloutput,reflectingknownsourcesofuncertaintyintheinputsandmodelstructure.
AtoolisneededtorunaMonteCarloanalysistoassesstheuncertaintyformodeloutputs.FarmersandlandownersarenotexpectedtoperformaMonteCarloanalysisontheirown.
Acentralizeddatabaseisneededtostoreinformationontheknownuncertaintiesassociatedwiththeactivityandemissionfactordataforeachemissionssource.Thisreportpresentsreadilyavailabledatathatcanformtheinitialfoundationforsuchadatabase.
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describedwithsummarystatistics,suchaslowerandupperboundsforintervalswithspecifiedconfidence,minimum,maximum,mean,andstandarddeviation.ThissummaryinformationformsthebasisforconstructingapproximatePDFsfortheMonteCarlomethod.RepeatedselectionsaremadefromthesePDFs.TheseselectionsrepresenttherangeofpossibleoutcomesfromeachPDF.RandomsamplingfromthePDFswillensuresuchrepresentativeness.5ByrandomlyselectingfromeachofthesePDFsandrunningtheselectedinputsthroughthemodel,arangeofoutputsisobtained.CombiningthesemodeloutputsacrossmanyrandomselectionsleadstoanoutputPDFthatcanbeusedtodescribeuncertaintyintheestimate,accountingforknownsourcesofuncertaintyintheinputsandmodelstructure.
Thissectionpresentsreadilyavailableinformationoneachofthekeycomponentsofuncertainty.Insummary,althoughinformationonallthecomponentsaredescribedhere,theMonteCarlomethodforassessingnetGHGemissionsuncertaintyreliesmostheavilyonparameteruncertainty,forwhichthebestPDFdataandinformationareavailable.Othercomponentsofuncertaintyarediscussed,includinglimitationssuchascharacterizingtheuncertaintyassociatedwithothercomponents.Thesecomponentscanbereadilyimprovedorrefinedintheuncertaintyanalysisasadditionalinformationbecomesavailable.Overalluncertaintyistypicallygreaterthananyparticularuncertaintycomponent(e.g.,sampling,largedatasets,models)andcanbereadilyimprovedorrefinedasadditionalinformationbecomesavailable.Astheuncertaintyassociatedwiththeothercomponentsisaddressed,theuncertaintywillincrease(i.e.,addressingonlyparameteruncertaintysetsalowerboundforoveralluncertainty).Therefore,thequantificationofparameteruncertaintysetsalowerboundforoveralluncertainty.
8.1.1 ParameterUncertainty
ParameteruncertaintyistheprimarysourceofuncertaintyinthenetGHGestimates.ThissectionpresentsreadilyavailableinformationonparametersusedtoestimatenetGHGemissionsfromanimalproductionsystems,croplandsandgrazinglands,andforestryGHGestimationmethods.Foreachinputvariable,readilyavailableinformationwascollectedontheprobabilitydistribution;variance;standarddeviation;expectedmean,median,andmode;mostlikelyvalue;minimum;maximum;relativeuncertaintyabsolutevalues;confidenceinterval;anddatasources.Theinformationwascollectedprimarilyfrompublishedliterature,suchastheIntergovernmentalPanelonClimateChange(IPCC)Guidelines(2006),theU.S.NationalGHGInventoryReport(U.S.EPA,2012),andpeer‐reviewedjournals.Intheabsenceofpublisheddata,defaultfactorsareindicatedbasedonexpertjudgmentobtainedfromtheWorkingGroups.TheinformationobtainedtodateispresentedinAppendix8‐B.6,7,8
5AnalternativeapproachtoselectingfromthePDFsisLatinhypercubesampling(McKayetal.,1979;HeltonandDavis,2003).6Uncertaintyfortheforestrysectorismainlydrivenbymodelingandsamplinguncertainty;consequently,onlyafewparametershavebeenlistedinAppendix8‐B.7TheWetlandsChaptermethodssuggestuseoftheFVSandDNDCmodelsincombinationwiththelookuptablesfordominantshrubandgrasslandvegetationtypesfoundinChapter3,forestimatingbiomasscarbon,soilcarbon,N2O,andCH4emissionsandremovalsinwetlands.Descriptionsofthesemodelsandtheuncertaintyassociatedwiththelook‐uptablesareincludedintheUncertaintyAssessment(Chapter8).8AnuncertaintyassessmentwasnotcompletedfortheLand‐useChangeChaptermethods(i.e.,annualchangeincarbonstocksindeadwoodandlitterduetolandconversion,changeinsoilorganiccarbonstocksformineralsoils)astheyarebaseduponIPCC2006GuidanceandnoU.S.specificcustomizationsweremadetothesemethods.Uncertaintyassessmentsforeachland‐useandtransitionintooroutofaland‐usecategory
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Inordertomaketheuncertaintyestimationprocessfeasibleandconsistentattheentityscaleforusebyanentityorlandowner,atoolwillbeneededthatprovidesthefollowinguncertaintyinformationforinputvariables:
PDFsordistributions–Default
Emissionfactors–Default
Activitydata–Default,butcustomizable
Withdefaultuncertaintyinformationavailable,itisfeasibletoquantifyparameteruncertaintyviaPDFsandtocombinetheuncertaintyviaMonteCarlomethods.ThesePDFsareoftenrelativelycrude,relyingondefaultvaluesandconservativeexpertjudgment.OptionstoimprovethePDFs(i.e.,improveparameteruncertaintyquantification)areto:(1)developamethodtohelpelicitandrefinetheseuncertaintydistributionsatanentityscale;and(2)conductnewresearchtobetterunderstandthekeyparametersidentifiedinthisreportandtoquantifytheiruncertainties.9
TheuncertaintyassociatedwiththevariousinputstotheGHGestimationequationormodelsarecombinedtoestimateoveralluncertaintyattheentitylevelfor:(1)eachsourcecategoryemissionestimate;and(2)totalemissionestimatearrivedatbyaggregatingeachsourcecategory’sestimate.Althoughmostinputswithinacategoryandacrosscategoriesareindependent,certainvariablesmightbethesame,similar,orhighlyco‐related,andwillneedtobeaccountedforappropriatelyintheuncertaintyanalysis.
8.1.2 SamplingMethodUncertainty
Somesamplingmethods(i.e.,fieldmeasurements)willbeconductedtosupporttheestimationofemissionsusingtheGHGquantificationmethods.Forexample,fortheforestrysector,conductingfieldmeasurementsonsamplingplotsforlargeforestandonurbanforestsisusedtodetermineaggregateforestcharacteristics(e.g.,treecover).Additionally,somelargedatasetsandexternalmodelsthatthemethodsusealsoutilizedatathatwereobtainedfromavarietyofoutsidesamplingmethods.Forexample,forestinventorydatausedintheforestvegetationsimulator(FVS)modelandthe averagecarbonsequestrationratesusedinthei‐Treemodelusedataobtainedthroughsamplingmethods.Inaddition,thereareinstancesintheseexternalmodelsandlargedatasetswherethevariationinmeasurementsobtainedfromthesamplingmethodsisnottakenintoaccount,buttheycanimpactuncertainty.
Ifforeststandsamplingisconductedatanentitylevelusingaformalprobabilitysamplingdesign,thenunbiasedestimatesofsamplingerrorvariancecanbecomputedviastandardtechniquesfromthefieldofsurveystatistics.Theexactformofthevarianceestimatedependsontheparticulardesignusedforthestandsampling.Thoughadditionaluncertaintiesarisefromtheactualmeasurementprotocolsusedinthefield,thesamplingerrorvarianceisamajorpartofthesamplinguncertainty.AcurrentlyfeasibleapproachtoincorporatinginformationonsamplingerrorvariancesintotheuncertaintyanalysisistomodelthesamplingerrorPDFasanormaldistributionwithzeroasitsmeanandtheestimatedsamplingerrorvarianceasitsvariance.10Thissection
arecontainedintheassociatedland‐usecategorychapterofthe2006IPCCGuidelines.http://www.ipcc‐nggip.iges.or.jp/public/2006gl/vol4.html9Atoolcouldprovideanoptiontousepre‐definedvaluessuchasthoseprovidedinAppendix8‐Boruser(i.e.,landowner)suppliedvaluestodefinePDFs.10Similarly,estimatesderivedfromexistingsurveysandtoolssuchasForestInventoryDataOnlineintheForestInventoryandAnalysisNationalProgramortheUSDANaturalResourcesInventory(NRI)SummaryReportshaveassociatedsamplingerrorvariancesfromwell‐establishedstatisticalprocedures.Inthesecases,
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providesthesamplingmethodsandtheirpotentialsourcesofuncertainty.However,giventhecomplexityinincorporatinginformationonuncertaintyforsamplingdataintheMonteCarlouncertaintyassessment,atoolwillbeneededtoquantifytheimpactofsamplinguncertaintyontheestimateofnetGHGemissions.11
8.1.2.1 ForestStandSamplingwithPlotsforUsewiththeForestVegetationSimulatorModel
TheFVSmodelisafamilyofforestgrowthsimulationmodelvariants.FVSestimatesforestcarbonstocksbasedonsampledataparameters(e.g.,thediameter,height,species,andcanopydensityoftreesfromrepresentativesampleplotsestablishedacrosstheforest).Forsamplingpurposes,anumberofplotsareestablishedwithinaforestthatcanserveasarepresentativesampleoftheentireforest.Asthevarianceinforesttypesincreases,thenumberofplotswillincrease.Thesizeandnumberofplotsshouldbedeterminedbasedonthevarianceincarbonstocksbetweenplots.Completeforestestimateshavesamplinguncertainty,butlargerandmorenumerousplotshelptocreateamorerepresentativesampleandlowertheuncertaintyassociatedwithcarbonstockestimatesproducedbyFVS.Bothpermanentandtemporaryplotscanbeusedinsampling;however,alargeruncertaintyisassociatedwithtemporaryplots.Notethattheuseofpermanentplotsisrecommendedinthisreport.Thistypeofsamplingmethodologyiscommonlyreferredtoasaforestinventory.
Onceplotshavebeendefined,alltreesaboveacertaindiameteratbreastheight(DBH)(commonly2.5cm.or1in.)aremeasuredandrecorded.12DBH,height,andavarietyofothermeasurementsarerecorded,butDBHaloneissufficientforusewithFVS.FVSusesDBHandavailableinformationtodevelopcarbondensityestimatesfortheentireforest.Ifprovided,FVSmodelsgrowthestimatesforfutureyearsbasedonaveragegrowthratesandvariablessuchasthinning.13SelectingplotstorepresententireforestsmeansFVSoutputsaresubjecttothesamplingmethoduncertainty.However,uncertaintyintheFVSoutputscanbelowered(i.e.,morerepresentativecarbonstockestimatescanbeobtained)bycollectingmoredetailedtreedatabeyondDBHaswellasensuringthatsampleplotsarelargeandnumerousenoughtocoverthevarietyoftreegrowthsettingsinaforest.
TheforestinventorydatarecommendedforusewithFVSinthisreportisbasedonthesamplingmethodsdescribedintheU.S.DepartmentofAgriculture(USDA)MeasurementGuidelinesfortheSequestrationofCarbon(Pearsonetal.,2007).Theseguidelinesalsodescribethepotentialuncertaintyassociatedwithsuchsamplingmethods.Accordingtothesemeasurementguidelines,areasonableestimateofthenetchangeincarbonstockswouldbewithin10percentofthetruevalueofthemeanatthe95percentconfidencelevelthatcanbeachievedbyhavingasufficientlylargesamplesize(Pearsonetal.,2007).Differentcarbonpoolsinaforestcanhavedifferentvariances;however,focusingonthestandinglivetreecomponentforforestryactivitiescancapturemostofthetotalvariance.
itmaybefeasibletousetheseestimatedvariancesfairlydirectly.Inothercases,itmightbenecessarytoconsidersmallareaestimationtechniquestodescribeuncertaintyaslarge‐scalesurveydataaredownscaledtoentitylevels.Describingthistypeofuncertaintywouldrequirebuildingstatisticalmodelsforcomplexsurveydataand,hence,isnotaddressedinthisreportasadditionalresearchisrequired.11Forexample,inaddressinguncertaintyingrowthofforestbiomass,algorithmstoaccountfornonlineargrowthpatternswillbeneeded.12Undercommonstandexams,eventreeslessthan2.5cmor1incanbemeasured,butthesetreesareoftenconsideredtobepartoftheunderstory(e.g.,byFIA).13Othervariables,suchasfertilization,onlyapplytoafewFVSvariants.
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TheforestinventorydatathatisusedformodelingthechangesinforeststandsislikelythelargestsourceofparameteruncertaintyfortheinputsandassumptionsusedintheFVSmodel;inaddition,therearemanycomponentsintheFVSmodelwherevariationinmeasurementsforthisdataisnottakenintoaccount.Forexample,thepotentialerrordistributionfrommonthtomonthincarbonstorageassociatedwithleavesandfoliageisnotaccountedforintheFVSmodel.
InaresearchpaperonobtainingsamplinguncertaintyinFVS,expertsnotethechallengeofreportingdistributionsofmodelinputsthatincludesamplinguncertaintyinFVSprojections(GreggandHummel,2002).Theystateintheirintroductionthat,“ithasn’tbeenpossibletocomputetheeffectsofsamplinguncertaintybecauseclassicalstatisticalmethodsarenotavailabletomakeinferencesaboutFVSprojections.Avarianceestimatorisnotavailablefortheresultsofsimulation.”
AsprovidedinAppendix8‐A,theFVSmodelprovidesquantitativeinformationontherangeandvariabilityofsamplingdata.ThisFVSapplication,calledFVSBoot,uses“bootstraps”todeterminefluctuationinestimateoutcomes(GreggandHummel,2002)(i.e.,allowsmodelertoempiricallyapproximatethesamplingdistributionofanystatistic/FVSattributeforwhichthemodelerwantstomakeinferences).
Bootstrapsampling14usingtheFVSBootprogramcanbeusedtoempiricallyapproximatethesamplingdistributionofstatisticsforwhichinferencesaretobedrawn.Newsamplesofstandconditionscanbegeneratedbysamplingtheoriginalplotswithreplacementtocreateabootstrapsample.Abootstrapmeancanbegeneratedfromthebootstrapsample.RepeatingthisprocessmultipletimeswillgenerateaMonteCarloapproximationofthedistributionofbootstrapmeans.Thestandarddeviationofthisapproximationwillbeanestimationofthetruestandarddeviationfortheentirepopulation.FVSBootdoesnotcoverallpotentialsourcesofvariationbutitcangiveameasureofimportantcomponentsofuncertaintyinFVSmodelprojections.WhiletheFVSBootprogramcanbeusedtodeterminethesamplinguncertaintyinFVS,itwasnotdevelopedoriginallytoproduceanoveralluncertaintyestimateforFVSoutputs.However,FVSBoothasbeenusedforsensitivityanalysisofsomeFVSoutputs(Hummeletal.,2013).AtoolwouldbeneededtofacilitatedevelopinganestimateoftheuncertaintybasedonacombinationoftheresultsfromtheFVSBootprogramandunderlyingequationsusedintheFVSmodel.
8.1.2.2 UrbanTreePopulationSamplingforUsewiththeFieldDataMethodUsingthei‐TreeEcoModel
Thei‐TreeEcomodelestimatesurbanforestcarbonstocksandgrossandnetannualcarbonsequestrationbasedonsampledataparameters(e.g.,thetreespecies,diameter,height,dieback,andcrownlightexposure)withacalculatedlevelofprecision.Asdesiredbythelandowner,alltreescanbemeasuredorarandomdistributionoffieldplotscanbemeasuredtoquantifytheurbantreepopulation.Largerandmorenumerousplotshelptocreateamorerepresentativesampleandlowertheuncertaintyassociatedwiththesampling.Thei‐TreeEcomodelusesthesampledataparametersandforest‐derivedallometricequationstoestimatecarbonvalues.Themodelalsoestimatesthestandarderroroftheestimatedcarbonvalue,whichisbasedonthesamplinguncertainty,ratherthantheerrorofestimationfromapplyingtheallometricequations.Estimationerrorisunknownandlikelylargerthanthereportedsamplingerror.AMonteCarlo
14Bootstrappingistheprocessofestimatingvariancebyrepeatedrandomsamplingwithreplacementofanexistingdataset.Forexample,todeterminetheprobabilitydistributionofaverageDBHforasampleof100trees,resamplesofthedatasetof100treescanbetakentoapproximatethevariance.
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analysistoolcouldusethestandarderroroftheestimatedcarbonvaluetoevaluatetheuncertaintyassociatedwithanentity’stotalnetGHGemissions.
8.1.2.3 SamplingandDAYCENTforEstimatingBiomassCarboninGrazingLandandAgroforestrySystems
SamplinguncertaintywillexistwhenestimatingbiomasscarbonusingthemethodprovidedinChapter3.Forexample,peakforageestimatesforgrazinglandscanbesampledusingthebiomassclippingmethod.15Thismethodisdestructivewiththeremovalofforagesamplesfromthefield.Thismethodhasbeenshowntoproduceestimateswithlowuncertainty(Lauenrothetal.,2006;Byrneetal.,2011).Non‐destructivemethodscanalsobeusedincludingthecomparativeyieldmethodforrangelands,16ortherobelpolemethodonrangelandsorpastures(Harmoneyetal.,1997;Vermeireetal.,2002).Thebiomassclippingmethodandcomparativeyieldmethodshavelessuncertaintythantherobelpoleorvisualobstructionmethod.Destructivesamplingmethods,however,aremoretimeandlaborintensive.UncertaintyassociatedwiththerobelpolemethodwasassessedintheBlackHillsofSouthDakotainastudybyUreskandBenzon(2007).Theauthorscompareddestructive(clipping)methodsforestimatingbiomassandtherobelpolemethod.Theyfoundtherewasalinearrelationshipbetweenthetwomethodsandthestandarderroroftherobelpoleestimateforasinglemeanwas373kgha‐1.Thestudyfurtherrecommendsthataminimumofthreetransectsbesampledformonitoringareaslessthan259hatobewithin20percentofthemeanand80percentconfident(UreskandBenzon,2007).InasimilarstudybyVermeireetal.,(2002),asinglevisualobstructionmodel(i.e.,robelpolemethod)effectivelyestimatedherbagestandingcropacrossrangetypesandproducedacoefficientofdeterminationof0.93.Anysamplingthatisdone,whetherdestructiveornon‐destructive,shouldoccuratlocationsthatarerepresentativeofthelandparcel.Ifsamplingtheforageisnotfeasible,defaultforageproductionvaluesareprovidedbytheUSDANaturalResourcesConservationService(USDA‐NRCS)inEcologicalSiteDescriptions.17Thesamplinguncertaintywilldependonthemethodusedtocollectthesampleandshouldbeprovidedbythefarmerorlandowner.
8.1.3 LargeDatasetUncertainty
InformationfromseverallargedatasetswillbeusedwiththeGHGquantificationmethodstoestimateemissionsfromtheanimalagriculture,croplandandgrazingland,andforestrysectors.Largedatasetscanbeconsideredanygroupingofdatapointsthatcoverawidetime‐seriesand/orlevelofreportedvariables.Thesedatasetsincludemultipledatalayers,GISdata,databases,andothersuchreportingcatalogues.
ThelargedatasetstobeusedincludetheSmithetal.(2006,alsoknownasGTR‐NE‐343),ForestInventoryandAnalysis,FVS,Daymet,andthedatasetfromthei‐Treemodel.Thesedatasetsprovidevaluesforestimationequationandmodelinputs.Theseinputsincluderegion‐andspecies‐specifictreegrowthrates,landandtreecover,inferredandobservedmeteorologicaldata,soiltypeanddistribution,ammoniacontent,andhistoricalclimatedatafortheNorthAmericancontinent.Thesedatawillbeusedtoinformthecarbondensitiesofsmallforestholdings,coverageofurbantrees,directandindirectN2Oemissions,soilpH,organicmattervalues,ambientairammoniaconcentrations,anddailyairtemperatureandvelocity.
15SeeSection15,“StandingBiomass”(USDANRCS,2011b).16SeeSection13,“DryWeightRank”(USDANRCS,2011b).17SeeUSDANRCS(2011a).
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Thissectionincludesadescriptionofthelargedatasetsusedforestimatingforestryandagroforestrysectorcarbonstocksandstockchanges,GHGemissionsandremovalsfromwetlands,soilcarbonstocks,andammoniaemissions.Thesectionalsoprovidesuncertaintyinformationobtainedfromthedatasetdevelopersandanapproachtoincorporatinguncertaintyassociatedwiththesedatasetsintotheoveralluncertaintyanalysis.
Manyofthelargedatasetsarecomplexandcovermultipleparameters.Insomeinstancesuncertaintyinformationisavailableforsomevariablesbutnotforothers,makingitdifficulttoassesstheuncertaintyoftheentiredataset.Table8‐1belowsummarizestheuncertaintydocumentationavailableforeachlargedatasetused.Themajorityofdatasetsdidnothavepublicallyavailabledocumentationcharacterizingtheassociateduncertainty.
Table8‐1:AvailabilityofUncertaintyInformationforLargeDatasets
DatasetName DatasetAbbreviation
AvailabilityofUncertaintyDocumentation
MethodsforCalculatingForestEcosystemandHarvestedCarbonwithStandardEstimatesforForestTypesoftheUnitedStates(Smithetal.,2006)
GTR‐NE‐343
Nopublishedquantificationofuncertainty.Standarderrorsavailableforcarbondensityforliveandstandingdeadtreesatthe50thand99thpercentileofvolume.
NationalLandCoverDatabase NLCDNopublishedquantitativeuncertaintyinformationfound.Authorsonlyprovideinformationoncontributingfactors.
DailySurfaceWeatherandClimatologicalSummaries
Daymet Nopublishedquantitativeuncertaintyinformationfound.
ContiguousUnitedStatesSoilGeographicDatabase
CONUSSTATSGO
Nopublishedquantitativeuncertaintyinformationfound.
SoilSurveyGeographicDatabase SSURGO Nopublishedquantitativeuncertaintyinformationfound.
AmmoniaMonitoringNetwork AMoNNopublishedquantitativeuncertaintyinformationfound.
Parameter‐ElevationRegressionsonIndependentSlopesModel PRISM
Nopublishedquantitativeuncertaintyinformationfound.
NorthAmericanRegionalReanalysis NARRRegional‐scaleaccuracyandbiasreportedbyMesinger(2006).
NaturalResourcesInventory NRI
Dataarecollectedusingatwo‐stagesamplingprocess.StatisticallyvaliduncertaintiesinmanagementpracticesarecomputableatMajorLandResourceAreasorStatelevel.
NationalAgriculturalStatisticsServiceAgriculturalCensus
NASS‐agriculturalcensus
Nopublishedquantitativeuncertaintyinformationfound.
NationalAgriculturalStatisticsService–CroplandDataLayer
NASS–CroplandDataLayer
NASSprovides accuracyinformationanderrormatrices(totalaccuracy,errorsofomissionandco‐mission),butnotonanannualbasisforcropsandStates.
EconomicResearchServiceCroppingPracticesSurvey
ERS‐CPS Nopublishedquantitativeuncertaintyinformationfound.
EconomicResourceServiceAgriculturalResourceManagementSurvey
ERS‐ARMSNopublishedquantitativeuncertaintyinformationfound.
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DatasetNameDataset
AbbreviationAvailabilityofUncertaintyDocumentation
NationalClimaticDataCenteroftheNationalOceanicandAtmosphericAdministration
NCDC(NOAA)
NCDCprovidesvaluesthatdescribetherangeoftheuncertainty,orsimply"range,"ofeachmonth’s,season's,oryear'sglobaltemperatureanomaly.Thesevaluesareprovidedasplus/minusvalues.
Modern‐EraRetrospectiveAnalysisforResearchandApplications
MERRA(NASA) Nopublishedquantitativeuncertaintyinformationfound.
NationalCentersforEnvironmentalPrediction NCEP(NOAA)
Nopublishedquantitativeuncertaintyinformationfound.
NationalAtmosphericDepositionProgram NADP
Regional‐scaleuncertaintywasassessedinDennisetal.(2011).
8.1.3.1 GTR‐NE‐343CarbonDensityValues
Estimatesofcarbonstocksandstockchangesfromthereport,“MethodsforCalculatingForestEcosystemandHarvestedCarbonwithStandardEstimatesforForestTypesoftheUnitedStates”(Smithetal.,2006)(USDAForestService,GeneralTechnicalReportNE‐343),arebasedonregionalaveragesandreflectthecurrentbestavailabledata.However,accordingtoGTR‐NE‐343,“quantitativeexpressionsofuncertaintyarenotavailableformostdatasummaries,coefficients,ormodelresultspresentedinthe[GTR‐NE‐343]tables.”GTR‐NE‐343lookuptablesincludesomeinformationabouttheconfidenceintervalsforliveandstandingdeadtreecarbondensitiesattwodifferentaveragevolumes(seeTable20ofGTR‐NE‐343),butitdoesnotprescribeamethodforapplyingthesesummaryuncertaintystatisticstostandlevelcarbonstockestimates.
Theuncertaintyassociatedwiththesereportedregionalaveragecarbonstockvaluesislikelyhigherasthesevaluesareappliedtosmaller‐scaleprojectsratherthanregions.Samplinguncertaintyassociatedwiththeregionalaverages,thatarebasedondatasummariesormodels,caninfluenceestimatesforspecificprojects.Theseprojectsaregenerallysmallsubsetsofaregion.Yet,variabilitywithinaregionforvaluesinadatasetwilllikelyhaveamuchgreaterinfluenceonuncertaintythantheactualsamplinguncertaintyassociatedwithcollectingregionalvalues(Smithetal.,2006).
OncetheuserfindsthetableinGTR‐NE‐343thatdescribestheforest’sspeciesmixandregion,theusercanusetheage(orvolume)oftheforeststand(whichisalsocollectedwithahighlevelofuncertainty)tofindoutthemetrictonsofcarbonperacredensityvalueforlivetreecarbon,downdeadwood,organicsoilcarbon,andothercategories.Theuncertaintyinformationisgivenas95percentconfidenceintervalsforthecarbondensityofliveandstandingdeadtrees,attwodifferentgrowingstockvolumes—the50thpercentileandthe99thpercentile.Theseconfidenceintervalsaregivenforeachforesttypeandregion.Tousethisinformationinanuncertaintyanalysisrequiresextrapolationtoothergrowingstockvolumes,whichrequiresmodelingtherelationshipbetweengrowingstockvolumeandvariationincarbondensity.Whilethesetablesaresimpleandeasytouse,theuncertaintyofresultsobtainedbyusingrepresentativeaveragevaluesmaybehighrelativetoothertechniquesthatusesite‐orproject‐specificdata.AdditionalresearchisneededtoincludethisuncertaintyintoaMonteCarloanalysisframework.
8.1.3.2 NationalLandCoverDatabaseMap
TheNationalLandCoverDatabase(NLCD)MapistheproductoftheMulti‐ResolutionLandCharacterizationpartnership,aconsortiumofFederalagenciesincludingtheU.S.GeologicalSurvey,EnvironmentalProtectionAgency(EPA),NationalOceanicandAtmosphericAdministration(NOAA),andtheUSDAForestServicethatarecontinuouslydevelopingdigitallandcoverdata.This
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associationhassuccessfullyprovidedlandcoverdataforthelower48States,Hawaii,Alaska,andPuertoRicofromdecadalLandsatsatelliteimageryandotherassociatedimagingdatasets.ThedatabaseprovidesLandsat‐based,30‐meterresolution,landcoveragecharacteristicsincludingthematicclass(e.g.,urban,agriculture,andforest),percentimpervioussurface,andpercenttreecanopycover.
Regardinguncertainty,theNLCDmapdocumentationindicates,“Unfortunately,thereisnoreadilyavailablereferencedatasetwithwhichtocomparetheinventorytogenerateaccuracystatistics.Referencedatahavetobespecificallygeneratedthroughmanualinterpretationofremotesensingdataforasampleoflocations,ashasbeendoneforaccuracyassessmentoflandcovermaps.Inlieuofsuchanapproach,whichisoutsidethescopeofthisstudy,thebestthatcanbedonecurrentlytodescribetheuncertaintyoftheinventorydataistoidentifytheknownconditionsthatcontributetoit”(NationalLandCoverDatabase,2008).
8.1.3.3 ContinentalUnitedStatesSoilGeographicDatabase
TheContinentalUnitedStatesSoilGeographicDatabase(CONUSSTATSGO)isadigitalgeneralsoilassociationmapthathasbeendevelopedbytheNationalCooperativeSoilSurveyanddistributedbytheUSDANRCS.Itconsistsofbroadbasedinventoryofsoilsandnon‐soilareasthatoccurinarepeatablepatternonthelandscapeandthatcanbecartographicallyshownatscaleandmapped.Noinformationisreadilyavailableontheuncertaintyassociatedwiththisdataset.
8.1.3.4 SoilSurveyGeographicDatabase
TheSoilSurveyGeographic(SSURGO)databasehasbeendevelopedbytheNationalGeospatialManagementCenter,formerlytheNationalCartographyandGeospatialCenter.TheSSURGOdatabasedepictsinformationaboutthekindsofsoilsanddistributionofsoilsonthelandscape.Thisdatasetisadigitalsoilsurveyandgenerallyisthemostdetailedlevelofsoilgeographicdataavailable.Uncertaintyinformationwasnotreadilyavailableforthisdatabasebeyondthedisclaimerthattheaccuracyofdatapoints‘metnationalmapaccuracystandards.’
8.1.3.5 AmmoniaMonitoringNetwork
TheAmmoniaMonitoringNetworkispartoftheNationalAtmosphericDepositionProgram(NADP),andwasoriginallyinitiatedbytheU.S.StateAgriculturalExperimentStations.Thedatasetprovidesconsistent,longtermrecordofammoniagasconcentrationsintheUnitedStates,drawingfrom50monitoringsitesacross37statesintotal.Uncertaintywasnotdirectlyaddressedinthedatasetmaterials,asidefromthedisclaimerthattheNADP’sCentralAnalyticalLaboratory(CAL)analyzes,qualityassures,andprovidestheanalyticaldatatotheNADP(2011).
8.1.3.6 Parameter‐elevationRegressionsonIndependentSlopesModel
TheParameter‐elevationRegressionsonIndependentSlopesModel(PRISM)isaclimatemappingsystemdevelopedbythePRISMClimateGroup.PRISMisaknowledge‐basedsystemthatusespointmeasurementsofprecipitation,temperature,andotherclimaticfactorstoproducecontinuous,digitalgridestimatesofmonthly,yearly,andevent‐basedclimaticparameters.Noinformationisreadilyavailableontheuncertaintyassociatedwiththisdataset.
8.1.3.7 DaymetWeatherDataset
DaymetisaweathermodeldevelopedbyOakRidgeNationalLaboratorythatprovidesinterpolationsextractedfromdailymeteorologicalobservationsontoagriddeddatasetwherenosuchobservationsarepresent.Daymetprovidesoutputparametersincludingtemperature,precipitation,humidity,solarradiation,andsnowwaterequivalent.TheDaymetdatasetisbasedon
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thespatialconvolutionofatruncatedGaussianweightingfilterwiththesetofstationlocations.Sensitivitytothetypicalheterogeneousdistributionofstationsincomplexterrainisaccomplishedwithaniterativestationdensityalgorithm.TheweatherdatasetsareproducedasoutputsfromtheDaymetmodelrun.ThisdatasetisusedasaninputforestimatingGHGemissionsfromcroplandsandgrazinglands,andammoniaemissionsfrommanuremanagement.Noinformationisreadilyavailableonuncertaintyassociatedwiththisdataset.
8.1.3.8 NorthAmericanRegionalReanalysisWeatherDataset
TheDAYCENTmodelsimulationsusetheNorthAmericanRegionalReanalysis(NARR)dataproductfordailytemperatureandprecipitation.TheNARRdatasetwaschosenbecauseitprovidesfull,gap‐filledcoveragefortheconterminousU.S.andismaintainedandupdatedregularly.AsdescribedbyMesinger(2006),“TheNationalCentersforEnvironmentalPrediction(NCEP)NorthAmericanRegionalReanalysis(NARR)isalong‐term,dynamicallyconsistent,high‐resolution,high‐frequency,atmosphericandlandsurfacehydrologydatasetfortheNorthAmericandomain.Itcoversthe25‐yearperiod1979–2003,andisbeingcontinuedinnear‐realtimeastheRegionalClimateDataAssimilationSystem,R‐CDAS.EssentialcomponentsofthesystemusedtogenerateNARRarethelateralboundariesfromandthedatausedfortheNCEP/DOEGlobalReanalysis,theNCEPEtaModelanditsDataAssimilationSystem,arecentversionoftheNOAAlandsurfacemodel,andtheuseofnumerousdatasetsadditionaltoorimprovedcomparedtothoseoftheGlobalReanalyses.Inparticular,NARRhassuccessfullyassimilatedhighqualityanddetailedprecipitationobservationsintotheatmosphericanalysis.Consequently,theforcingtothelandsurfacemodelcomponentofthesystemismoreaccuratethaninpreviousreanalyses,sothatNARRprovidesamuchimprovedanalysisoflandhydrologyandland‐atmosphereinteraction.”Noquantitativeinformationisreadilyavailableonuncertaintyassociatedwiththisdataset.
8.1.3.9 DAYCENTLandManagementDataSets
Dataonpastlanduseandmanagement(priortotheyear2000)arethebasisforrepresentativecroplandmanagementsystems,selectedbytheentitylandowner,thatareusedtoinitialize(“spinup”)theDAYCENTmodelforcomputingsoilorganiccarbonstockchanges.TheattributesofthemanagementsystemsarebasedprimarilyonthreelargedatasetsfortheUS:theNationalResourcesInventory(NRI),theNationalAgriculturalStatisticsService(NASS)croplandsurveys,andUSDAEconomicResearchServiceCroppingPracticesSurvey.TheuseofrepresentativecropmanagementsystemsfortheDAYCENTinitializationprocessintroducessomeuncertaintywhenappliedtoaspecificfarmorranchentity(whichhasauniquemanagementhistorythatmaybedifferentfromtheregionally‐basedrepresentativemanagementhistoriesspecifiedbyMajorLandResourceAreas.However,themajoruncertaintyforthemodelinitializationisdrivenbythetimingofmajorland‐coverchange(e.g.,conversionofgrasslandtocropland)whichcanbeuser‐specifiedfortheparticularentityandlandparcel.
NationalResourcesInventory.TheNRIisaninventoryoflandcoveranduse,soilerosion,primefarmland,wetlands,andothernaturalresourcecharacteristics.NRIwasdesignedasatooltoassessconditionsandtrendsforsoil,water,andrelatednaturalresourcesprimarilyonnon‐FederallandsoftheUnitedStates(NusserandGoebel,1997).TheNRIisastratifiedtwo‐stageareasampleofoverseveralhundredthousandpointsdistributedacrosstheUnitedStatesandCaribbean.Eachpointinthesurveyisassignedanareaweight(i.e.,expansionfactor)basedonotherknownareasandland‐useinformationsothateachpointhasastatisticallyassignedareathatitrepresents(NusserandGoebel,1997).Itshouldbenotedthatthereissomeuncertaintyassociatedwithscalingthepointdatatoaregionorthecountryusingtheexpansionfactors.Ingeneral,thoseuncertaintiesdeclineatlargerscales,suchasStatescomparedtosmallercountyunits,becauseofalargersamplesize.
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NationalAgriculturalStatisticsServiceCropSurveys.DatafromtheNASScountyagriculturalproductionsurveyswereusedtoconstructrepresentativecroprotationsfortheperiodpriorto(i.e.,before1979)thedatarecordintheNRI.NASSconductsthousandsofsurveyseachyearcoveringmanyfacetsofU.S.agriculture.Estimatesincludecropacreage,yield,production,irrigation,andlivestocknumbers.State‐levelcropestimatesareavailablefromasearlyas1866dependingontheStateandvariableofinterest.Somecounty‐levelcropdataisavailablefromasearlyas1915,withmostcropsavailableformostStatesbyabout1960.Dataaggregatedtothecountylevelaresubjecttoahighlevelofqualitycontrol,includingdatascreeningforoutliers,doublecheckingwithprimarydatacollectorsandcomparisonswithotheraggregatedatasetssuchasfromtheUSDAFarmServicesAgency.
USDAEconomicResearchService(ERS)CroppingPracticesSurvey.AncillarydataonhistoricalmanagementpracticesusedintheDAYCENTmodelinitializationincludenitrogenfertilizerrates(USDAERS,1997;2011).Meanfertilizerratessince1990wereestimatedforallmajorcrops,summarizedbyERSattheState‐level.IfaStatewasnotsurveyedforaparticularcroporiftherewerenotenoughdatatoproduceaStatelevelestimate,thendatawereaggregatedtoUSDAFarmProductionRegionsinordertoestimateameanandstandarddeviationforfertilizationrates(FarmProductionRegionsaregroupsofStateswithsimilaragriculturalcommodities).Crop‐specificregionalfertilizerratespriorto1990werebasedlargelyonextrapolationorinterpolationoffertilizerratesfromtheyearswithavailabledata.Forcropsinsomeagriculturalregions,littleornodatawereavailable,and,therefore,ageographicregionalmeanwasusedtosimulatenitrogenfertilizationrates(e.g.,nodataareavailablefortheStateofAlabamaduringthe1970sand1980sforcornfertilizationrates;therefore,meanvaluesfromthesoutheasternUnitedStateswereusedtosimulatefertilizationtocornfields).Nouncertaintydataareavailableforthisdataset.
8.1.3.10 DNDCInputDatasets
TheDeNitrification‐DeComposition(DNDC)modelisproposedtoestimateGHGemissionsandremovalsfromwetlandssystems.DNDCisasoilbiochemistrymodelthatsimulatesthermodynamicandreactionkineticprocessesofcarbon,nitrogen,andwaterdrivenbytheplantandmicrobialactivitiesinecosystems(OlanderandHaugen‐Kozyra,2011).TheDNDCmodelreliesonspecificinputdatasetsthatcanbecategorizedintofivesources:(1)cropland/land‐usedata;(2)cropmanagementdata;(3)soilsdata;(4)weatherdata;and(5)atmosphericdepositiondata(Salasetal.,2012).Theseprimarysourcesofdataanduncertaintyassociatedwiththedatasetareprovidedbelow.
NationalAgriculturalStatisticsServiceCroplandDataLayerdataset.TheDNDCmodelusestheNASSCroplandDataLayerasasourceofcropland/land‐usedata.TheNASSCroplandDataLayerisanonlinegeospatialexploringtoolgeneratedfromsatelliteimageobservationsata30meterresolution.NASSprovidesaccuracyinformationanderrormatrices(totalaccuracy,errorsofomissionandco‐mission),butnotonanannualbasisforcropsandStates.NASSAgriculturalCensus.Thecensusisavailableeveryfiveyears,andusedatthecountyscale.ItprovidesinformationonU.S.farmsandranchesandistheonlysourceofuniform,comprehensiveagriculturaldataatthecountylevel.Farmersandranchersareaskedtorespondtothecensusbymailoronline.Informationincludingproductionexpenses,marketvalueofproducts,andoperationcharacteristicsareafewofthecategoriesofdata.Uncertaintyisnotassessedforthesedata.RemoteSensing.DNDCusesremotesensingtobuildregionaldatabasesoncroplandonaprojectandasneededbasis.TherangeofsensorsusedincludesRapidEye,Landsat,MODIS,andSAR(PALSAR,Radarsat,ENVISAT,etc.).Remotesensingisusedforestimatinghydroperiods(i.e.,wherethewatertableisatanygiventime).AsDNDCdoesnothaveagroundwatermodelingcomponent,
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remotesensingisusedtoidentifywhenwetlandsareflooded.Uncertaintyisnotassessedforthesedata.USDA,ERSAgriculturalResourceManagementSurvey(ARMS).ARMSdataareusedtopopulatethecropmanagementcomponentoftheDNDCmodule.USDAERSARMSprovidedataonthefinancialcondition,productionpractices,andresourceuseoffarmersatthefieldlevelwithintheUnitedStates.ARMSdataarereleasedand/orrevisedtwiceayear.Uncertaintyisnotassessedforthesedata.CONUSSTATSGO(Seedescriptionabove).Thesedataareusedtoassociatesoiltypesanduncertaintyofsoilsdatawithinthemodel.SSURGO(Seedescriptionabove).SSURGOdataareretrievedbyDNDCviaanautomatedretrievalscriptandextractfourkeysoilattributes:claycontent(texture),bulkdensity,organicmatter(soilorganiccarbon),andpH.NOAANationalClimaticDataCenter.DNDCusesstationdatafromtheNOAANationalClimaticDataCenter(NCDC)toinputtemperature,dewpoint,relativehumidity,precipitation,windspeedanddirection,visibility,andatmosphericpressure.Dataareprovidedatthesubhourly,hourly,daily,monthly,annual,andmultiyeartimescale.NCDCprovidesvaluesthatdescribetherangeoftheuncertainty,orsimply"range,"ofeachmonth,season,oryearglobaltemperatureanomaly.Thesevaluescanbeusedasplus/minusvalueswithinanoverallMonteCarloframework;however,atoolisneededtoutilizethisinformation.Daymet(Seedescriptionabove).TheseweatherdataareusedbyDNDCandhavebeenavailableformuchofNorthAmericafrom1980to2012.Uncertaintyinformationisnotavailableforthisdataset.NationalAeronauticsandSpaceAdministrationModern‐EraRetrospectiveAnalysisforResearchandApplications(MERRA).TheDNDCmodelreliesonMERRAsatellitedataasinputforthehydrologicalcycle.MERRAprovidesglobaldataonvariousaspectsofmoisturedistributionandvariability.Nearly30yearsofdataareavailableandhasundergoneanonlinebiascorrectionforsatelliteradianceobservations.Thiswasdonetocalibrateobservationsfromdifferentsatellites.UncertaintydataarenotavailableforMERRAoutput.NationalOceanicandAtmosphericAdministrationNationalCenterforEnvironmentalPrediction(NCEP).DNDCinputsNCEPnationalweather,water,andclimatedataintotheNCEPmodel.NCEPcreatesclimate,water,ocean,space,andenvironmentalhazardoutputs.UncertaintydataarenotavailableforNCEPoutput.NationalAtmosphericDepositionProgramNationalTrendsNetwork(NTN)Stations.DNDCrequirestotalnitrogendepositionandestimatesofaverageconcentration.DNDCreliesontheNADPNTNstationstoinputtotalnitrogendeposition(NO3andNH4)intothemodel.NADPNTNstationscollectprecipitationandchemistrysamplesawayfromurbanareaandpointsourcesofpollution.Thestation’sCentralAnalyticalLaboratoryreviewsdataforcompletenessandaccuracyandflagssamplesthatweremishandledorcompromised.SampledataarefurtherreviewedbytheNADPprogramofficetodoafinalchecktoresolvediscrepancies.Oncedataaremadeavailableonline,DNDCcalculatesmeannitrogendepositionforthesimulationtimeperiodandincorporatesthedataintotheprojectdatabase.NADPNTNstationdatadonothaveassociateduncertaintydataavailable,howeverregionaluncertaintywasanalyzedinapresentationbyDennisetal.(2011).
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8.1.3.11 ApproachforIncorporatingLargeDatasetUncertainty
AmongthelargedatasetstobeusedfortheGHGquantificationmethods,onlyGTR‐NE‐343hassomequantifieduncertaintyinformationforuseinaMonteCarloassessmentofnetGHGemissions.Becauseconfidenceintervalsforonlytwostockvolumesareavailable,onlyalinearrelationshipcanbemodeledwithGTR‐NE‐343information,andnodeparturesfromlinearitycanbeassessed.Furtheranalysisofcarbondensityatothergrowingstockvolumesrequirescomputationofadditionalconfidenceintervals.
Giventhelackofuncertaintyinformationformostoftherelevantlargedatasets,estimatingthissourceofuncertaintyisnotfeasible.Instead,relianceofthemethodsonthelargedatasetsisexplicitlyacknowledgedandreadilyavailableinformationonuncertaintyissummarizedasprovidedabove.
Somelarge“wall‐to‐wall”datasetsareformedviainterpolationofexistingdatafromafixedsetofmeasurementlocations.Forsuchdatasets,apotentialnear‐termnextstepmightbetoincorporateuncertaintybyimputingmeasurementsfromrandomly‐selectedmeasurementlocations.Thisrandomselectioncoulduseprobabilitiesinverselyproportionaltothedistancebetweenthemeasurementlocationsandtheentity.Ifmostlocationsarefarfromtheentity,thentheimputationsareincreasinglyuncertain.
Inthelongerterm,bothnewresearchandsynthesisofexistingresearchwillberequiredtoquantifylargedatasetuncertainty.Methodsfromgeostatistics,forexample,mightbeusedtodescribeanuncertainlargedatasetobtainedbyinterpolation.
8.1.4 ModelUncertainty
Inthecaseoftheexternalmodels,itishardtoappropriatelyaccountforapproximationerrorandoftenonlyonemodelexiststorepresentorestimateemissions(orremovals)fromaspecificactivityorprocess.Sincecomparablemodelsdonotexist,itisalmostimpossibletoestimatetheuncertaintyassociatedwithusingoneparticularmodelversusanother.Whilethisreportspecifiestheuseofseveralexternalmodels—DAYCENT,DNDC,FVS,i‐TreeCanopy,i‐TreeEco,FirstOrderFireEffectsModel(FOFEM)—giventheaboveconsiderations,limitedpublisheddatawasfoundonexternalmodeluncertaintyinherentwiththesemodels.
Thissectionincludesadescriptionoftheexternalmodelsusedforestimatingcarbonstocksandstockchangesfromthecroplandsandgrazinglands,wetlands,andforestrysectors,uncertaintyinformationobtainedfromthemodeldevelopers.Thesemodelshelpprovideaquantitativeandgeographicalviewintotheemissionsassociatedwithavarietyoffactorsfromagriculturalandforestrysystems.Forexample,giveninputssuchasarea,treediameter,treeheight,species,soiltype,andgeography,thesuiteofforestrymodelscanprovideemissionestimatesfromfiredisturbances,approximatechangesinforestcarbonstocks,orprovideurbanforestcarbonstockdata.Table8‐2belowsummarizestheuncertaintyinformationobtainedfromthemodeldevelopersforeachofthemodelsusedtoestimatenetGHGemissions.Giventhelackofquantitativeinformationonmodeluncertainty,thiscomponentofuncertaintywillnotbepartoftheMonteCarlouncertaintyassessment.
Table8‐2:UncertaintyInformationforProcess‐basedModels
ModelAvailabilityofUncertainty
DocumentationOccurrenceofUncertaintyBiases
DAYCENT Ogleetal.,2010BiasesbypracticearequantifiedinOgleetal.(2010).
DNDCa Inputuncertainty:Lietal.(2002) andZhangetal.(2009).Therehavebeen
AMonteCarloapproachorMostSensitiveFactoranalysiscanberunoncertaininputparameters
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ModelAvailabilityofUncertainty
DocumentationOccurrenceofUncertaintyBiases
nopapersfocusedonquantificationofDNDCmodelstructuraluncertainty.
(i.e.,soilmeasurements)toassessthevariabilityoftheparameters(includesexcerptsfromC_AGGwhitepaperbySalasetal.,2012).
ForestVegetationSimulator
Nopublishedquantificationofmodeluncertaintywasfound.
Existsbutnotquantifiableaccordingtoexperts.
i‐TreeCanopy(AerialDataMethod)
Nopublishedquantificationofmodeluncertaintyfound.
Modelbiasislikelylow,accordingtomodeldeveloper.
i‐TreeEco(FieldDataMethod)
Nopublishedquantificationofmodeluncertaintyfound.
Valuesarestandardized,biasisminimized.Unknownbiasfornationaldensityestimates.
FirstOrderFireEffectsModel
Nopublishedquantificationofmodeluncertaintyfound.
Regionalbiases(NorthRockyMountains,PacificNorthwestregions).
aDNDCdoesnotprovideuncertaintyparameterizationofoutputsatthesitelevel,however,theregionalmodelprovidesanoptionforassessinguncertaintyduetoinputuncertainty.
8.1.4.1 DAYCENTModel
TheDAYCENTmodelhasinherentuncertaintyassociatedwithpredictingsoilorganiccarbon(SOC)stockchanges(Ogleetal.,2010;U.S.EPA,2013).Theuncertaintyisassociatedwithimperfectsimulationoftheplantandsoilprocessesassociatedwiththealgorithmsandparameters.Toaddressthisuncertainty,thesimulatedmodelpredictionsofSOCstocksneedtobecomparedtomeasurements.Thecomparisonleveragesthescalabilityoftheprocess‐basedmodeltothewiderangeofconditionsthatexistinagriculturallands,whilehavinganunderlyingmeasurementbasistosupportthereporting(Conantetal.,2011).
ThedifferencesbetweenmeasurementsandsimulatedSOCstocksandstockchangeshavebeenanalyzedusinganempiricallybasedapproachinwhichastatisticalmodelwasdevelopedthatquantifiestheaccuracyandprecisioninthesimulatedpredictions(Ogleetal.,2007).Thelinearmixed‐effectmodelingapproachwasusedforthisanalysis,andvariousenvironmentalconditions(e.g.,climateandsoilcharacteristics)andmanagementpracticeswereevaluatedtodetermineifthemodelismoreaccurateorpreciseforparticularconditionsormanagementsystems.TheapproachreliedonmeasurementsofSOCstocksfromanetworkofsitesacrosstheU.S.agriculturallands.AnetworkiscurrentlybeingexpandedbytheUSDANRCSthatisexpectedtoprovideadditionalmeasurementssupportingtheentity‐scalemethodsforestimatingSOCstockchanges.ThisuncertaintyanalysiswillbeupdatedasnewmeasurementsbecomeavailablefromthenetworkandwillbeincorporatedintoaMonteCarloassessment.
8.1.4.2 DNDCModel
Structuraluncertaintyisrelatedtotheinherentuncertaintyofamodelthatremainsevenifnoneoftheinputdatahadanyvariability.Estimatingmodelstructuraluncertaintyrequirestheuseofindependentvalidationdata(i.e.,fieldmeasurementdatathatwerenotusedtodevelopthemodelalgorithms).Thisapproachrequiresnotonlyaccesstosufficientindependentfielddata,butalsothatthedataincludealltheinputdatathatDNDCrequires.AnumberofvalidationtestswithindependentfielddatahavebeenpublishedalthoughsummarystudiesarecurrentlynotavailabletoquantifyDNDCstructuraluncertainty.
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8.1.4.3 ForestVegetationSimulator
Aspreviouslydescribed,asourceofuncertaintyfortheFVSmodelissamplinguncertaintyassociatedwiththetreelist(themainuserinput).Theadditionaluncertaintyassociatedwiththemodeluncertaintyisdifficulttoquantify.
IntheFVSmodel,diametergrowthistheonlyvariablethatisconsideredstochastic.Forthediametergrowthmodule,arandomseedisusedforprojectionsofchangesinforeststandsratherthanusingthemeandiametervaluetoavoidunderestimatinggrowth.Thisprocessincreaseserrorpropagationbecausetheresultsofthediametergrowthmoduleareusedtomakefurtherestimatesinthemodel,e.g.,usinggrowthandyieldequations(i.e.,Jenkinsequations).However,thestochasticityofdiametergrowthisnotthemaindriverofmodeluncertainty.UncertaintyassociatedwiththeFVSmodeliscomplexbecauseitisderivedfrom20differentregionallyspecificmodelvariantsthatweredevelopedindependently.Eachmodelrunoranalysishastobecalibratedtoaccountforlocaltreevarietyandgrowthrates,introducinganotherlevelofcomplexity(VanDyck,2012).Additionally,errorsmaypropagatefromthebiasinregionalfactors,adjustingtolocalgeographies,climates,theuseoffielddata,andsamplinguncertainty.Giventheoverallcomplexityinherentinthemodel,FVSdoesnotincorporateuncertaintyintheoutputorpost‐analysisofmodelrunsandadditionalresearchisrequiredtoquantifymodeluncertainty.
8.1.4.4 i‐TreeModel
i‐Tree(formerlytheUrbanForestEffectsmodel)isanurbanforestryanalysismodeldevelopedbyDavidJ.Nowak(USDAFS),DanielE.Crane(NRS),andPatrickMcHale(SUNYCollegeofEnvironmentalScienceandForestry).Thei‐Treemodelhelpsquantifythestructureofcommunitytreesandtheenvironmentalservicesthattheyprovide.Itprovidessixanalyticaltoolsincluding:
i‐TreeEco:Providesafullpictureoftheentireurbanforest(usedintheFieldDataMethod)
i‐TreeStreets:Quantifiesbenefitsfromamunicipalitiesstreetleveltrees
i‐TreeHydro:Modelstheeffectsoftreesonwatershedstreamflowandwaterquality
i‐TreeVue:UsesNLCDsatelliteimagerytoassesstreecanopy
i‐TreeDesign:Assessesmultipletreesatparcellevel
i‐TreeCanopy:Providesaquantifiableestimateoftreecoverandotherlandcovertypes(usingintheAerialDataMethod)
i‐TreeEcoandi‐TreeCanopyarerecommendedinthisreportforusebyanentitytoestimatethechangeincarbonstocksintheirurbanforests.
i‐TreeEcoUncertaintyInformation:Thei‐TreeEcomodelproducesuncertaintyestimatesbasedonsamplingerror,butitdoesnotcalculateamodelestimationerror.Accordingtoi‐Treedevelopers,estimationerrorisbasedontheuncertaintyinherentinthebiomassconversionequationsandemissionfactors.Thedevelopersalsonotethatmodelbiasislikelylowgiventhattheinputassumesagivenrandomsampleoftrees,andtreespeciesequationsareselectedbasedonstandheight.Ifaparticularspeciesequationisnotavailablethemodelusestheaverageofavailableequationsfromtheclosestgenera(Nowak,2012).AMonteCarloanalysistoolcouldusethestandarderroroftheestimatedcarbonvaluetoevaluatetheuncertaintyassociatedwithanentity’stotalnetGHGemissions.
i‐TreeCanopyUncertaintyInformation:Thei‐TreeCanopymodelproducesastatisticalestimateofthestandarderrorofthepercenttreecoverestimatebasedontheratioofsamplepoints
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classifiedastreestototalsamplepoints.Ini‐TreeCanopytheuserimportsashapefile,samplespoints,andclassifiesthemaseithertreesornon‐trees.Ananalysisofthetreepointtototalpointratioisusedtoestimatethestandarderrorassociatedwiththepercenttreecoverestimate,asdescribedinthei‐TreeCanopytechnicalnotes,18andshowninEquation8‐1below.
Table8‐3showsestimatesofthestandarderrorasrelatedtotheratiooftreepointstototalsamplepoints(pvalue),wherethetotalnumberofsampledpoints(N)equals1,000.
Basedonthestandarderrorformula,standarderrorisgreatestwhenpequals0.5,andisleastwhenpisverysmallorverylarge(seeTable8‐3).AMonteCarloanalysistoolcouldusethestandarderroroftheestimatedpercenttreecovervaluetoevaluatetheuncertaintyassociatedwithanentity’stotalnetGHGemissions.
8.1.4.5 FirstOrderFireEffectsModel
FOFEMisacomputationalmodelforpredictingtreemortality,fuelconsumption,smokeproduction,andsoilheatingcausedbyeitherprescribedfireorwildfire.FOFEMwasdevelopedbytheIntermountainFireSciencesLaboratoryinMissoula,MT,oftheUSDAForestService.FirstorderfireeffectsarethosecharacterizedwiththedirectimmediateconsequencesofafireincludingGHGemissionestimates.FOFEMisdividedintofournationalregions:PacificWest,InteriorWest,NorthEast,andSouthEast.Themodelincludesseveralforestcovertypestoprovideanadditionallevelofdetailresolution.Thequantitativeoutputcanbeusedinassessmentsafterfiredamage,inanalyzingprescribedfireimpacts,andmodelingvulnerabilitiesinregionalforestgroups.
FOFEMhasaregionalbiasgiventhattheempiricalrelationshipsandassumptionsarebasedonforestedsystemsintheNorthRockyMountainsandthePacificNorthwest.However,theseuncertaintiesarenotquantifiedoradjustedforuseindifferentregions.Forinstance,SoutheastfiresburnwellathumiditylevelsthatwouldnotsupportthemintheWest.Thisphenomenonisnotaccountedforinthemodelandthereisnouncertaintyquantificationaroundtheoutput.Therearealsomaterialdifferencessuchaslitterbulkdensitythatinfluencesconsumptionandemissionwhichcanvaryconsiderablyregiontoregion(Lutes,2012).
18I‐TreeCanopyTechnicalNotes:http://www.itreetools.org/canopy/resources/iTree_Canopy_Methodology.pdf
Table8‐3:EstimatesofStandardError(SE)(N=1,000)ofPercentTreeCoverfromi‐TreeCanopywithVaryingpValues
p SE0.01 0.00310.1 0.00950.3 0.01450.5 0.01580.7 0.01450.9 0.00950.99 0.0031
Equation8‐1:EstimatingStandardErrorofPercentTreeCoverfromi‐TreeCanopy
/ (e.g., 0.33 0.67/1000=0.0149)
Where:
N=Totalnumberofsampledpoints(e.g.,1,000)
n=Totalnumberofpointsclassifiedasatree(e.g.,330)
p=n/N(e.g.,330/1,000=0.33)
q=1− p(e.g.,1− 0.33=0.67)
Chapter 8: Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
8-20
8.1.4.6 ApproachforIncorporatingModelUncertainty
Giventhelackofuncertaintyinformationformostoftherelevantexternalmodels,itisnotcurrentlyfeasiblefortheGHGquantificationmethodstoquantifythissourceofuncertainty.Instead,relianceofthemethodsonthemodelswillbeexplicitlyacknowledged.Thepotentialimpactsofuncertainmodelsontheaccuracyandprecisionoftheresultingestimatesisdescribedqualitativelyintheprevioussections.
Itmaybepossibleintheneartermtoelicitexpertjudgmentsonthelevelofmodeluncertaintyattheentitylevel.ModelsusedintheGHGquantificationmethodsaretypicallyconstructedatscalesnosmallerthantheentitylevel.Itisexpectedthatthemodeluncertaintyattheentitylevelwouldbenosmallerthanthemodeluncertaintyatthemodel’sscale,andpossiblylargerduetoadditionalerrorfromdownscalingtotheentitylevel.
Inthelongerterm,moreresearchisneededtoevaluatemodelpredictionswithindependentdata,notusedinthedevelopmentofthemodel.Thedifferencesbetweenmodelpredictionsandindependentdataarethebestpossiblesourceofinformationregardingmodeluncertainty.
ResearchGaps8.2
ThereadilyavailableinformationonparameteruncertaintyisprovidedinthetablesinAppendix8‐B.Asindicated,muchoftheinformationtocharacterizetheuncertaintyisnotavailableandthedatathatareprovidedaremostlydefaultvaluesfromtheliteratureandassumedprobabilitydensityfunctions.ToconductaMonteCarloanalysisforuncertaintyestimation,itisimportanttoobtainprobabilitydensityfunctionsorsummarystatisticsforalluncertainvariables.SignificantresearchisneededtoobtainnewdataandtosynthesizeexistingandnewdatainordertotrulyassessuncertaintyassociatedwitharangeoffactorscausinguncertaintyintheGHGestimatesdevelopedusingtherecommendedmethodsdescribedinthisreport.Inparticular,moreresearchisneededtoassessparameter,sampling,largedatasets,andmodeluncertainties.
Chapter 8: Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
8-21
Appendix8‐A:ExampleOutputFilefromFVSSamplingUncertaintyBootstrappingApplicationFVSBoot(asprovidedinGreggandHummel,2002)
ThefollowingtableillustratesstandarddeviationsurroundingthesamplingerroroftheBasalAreaoutputs.FVSBootcanbeconfiguredtodeterminestandarddeviationofthesamplingerrorforanyFVSoutput.
Table8‐A‐1:ExampleOutputFilefromFVSSamplingUncertaintyBootstrappingApplicationFVSBoot(asprovidedinGreggandHummel,2002)
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Appendix8‐B:UncertaintyTables
Thissectionpresentsreadilyavailabledataontheuncertaintyassociatedwithactivityandemissionfactordata.Table8‐B‐1liststhedata
elem
entsthatareprovidedinthesubsequenttablesforeachagriculturesystem.Inparticular,readilyavailableuncertaintyinform
ationis
providedinthefollowingtables:
Table8‐B‐2:CroplandUncertaintyTem
plate
Table8‐B‐3:AnimalPopulationUncertaintyTem
plate
Table8‐B‐4:EntericFermentationandHousingUncertaintyTem
plate
Table8‐B‐5:M
anureManagem
entUncertaintyTable
Table8‐B‐6:ForestryUncertaintyTable
Table8‐B‐1:DataElem
entsProvided
ColumnLabel
Description
DataElem
entNam
eThenam
eofthevariable
Abbreviation/Symbol
Theshorthandrepresentationusedinthereport
EmissionType
Emissionsestimatesthatdependonthedataelement(CH
4,N2O,NH3,CO
2)DataInputUnit
Unitassociatedwiththedataelement
InputSource
Entityentry,defaultentry,m
odeloutput,orfrom
adatabase
Statistic
Availablestatisticfortheparameter
TypeofStatistic
Mean,median,ormode
ProbabilityDistributionType
Theprobabilitydistributionfunctionofthedataelem
ent(normal,lognormal,uniform,triangular,beta)
RelativeUncertainty
Rangeofvaluesaroundthemostlikelyvalue,expressedasapercentofthemostlikelyvalue
ConfidenceLevel
Theprobabilitythattheconfidencerangecapturesthetruevalueofthedataelem
entgivenadistributionof
samples.
EffectiveLowerLimit
Minimum
valuefordataelement(excludingoutliers)
EffectiveUpperLimit
Maximum
valuefordataelement(excludingoutliers)
DataSource
Referenceforinformationrelatedtothedataelementandassociateduncertainty
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Table8‐B‐2:CroplandUncertaintyTem
plate
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Croplands–MultipleSub‐
sources
Area
A
CH4,N2O,
CO2
Hectares
Entity
Entry
Croplands–MultipleSub‐
sources
CropYield
YCH
4,N2O,
CO2
Metrictonsdry
mattercrop
yield/year
Entity
Entry
Croplands–MultipleSub‐
sources
Meatyieldper
parcelofland
Meat
CO2
kgcarcass
yield
Entity
Entry
Croplands–MultipleSub‐
sources
Milkproduction
perparcelofland
MilkProd.
CO2
kgfluidmilk
yield
Entity
Entry
BiomassCarbonStock
Changes
Meanannual
woodybiomass
(t=currentyear's
stocks)
Wt
CO2
Metrictons
CO2‐eqyear‐1
Model
Output
DAYCEN
T
model
simulations
andgrow
th
functions
foragro‐
forestry
BiomassCarbonStock
Changes
Meanannual
woodybiomass(t‐
1=Previousyear's
stocks)
Wt‐1
CO2
Metrictons
CO2‐eqyear‐1
Model
Output
DAYCEN
T
model
simulations
andgrow
th
functions
foragro‐
forestry
BiomassCarbonStock
Changes
Meanannual
herbaceous
biom
ass
(t=currentyear's
stocks)
Ht
CO2
Metrictons
CO2‐eqyear‐1
Entity
Entry
BiomassCarbonStock
Changes
Meanannual
herbaceous
biom
ass(t‐
1=Previousyear's
stocks)
Ht‐1
CO2
Metrictons
CO2‐eqyear‐1
Entity
Entry
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
BiomassCarbonStock
Changes
ForageYield
Forageyield
forgrazing
lands
CO2
Metrictonsdry
matterper
hectare
Entity
Entry
BiomassCarbonStock
Changes
Num
beroftrees
byageofdiameter
classforeach
agroforestry
practice
Num
berof
Trees
CO2
Num
ber
Entity
Entry
BiomassCarbonStock
Changes
Diameteratbreast
heightfora
subsam
pleoftrees
DBH
CO2
Meters
Entity
Entry
BiomassCarbonStock
Changes
RoottoShoot
Ratio
R:S
CO2
Ratio
Default
Entry
Westetal.
(2010)
BiomassCarbonStock
Changes
Drymatter
contentof
harvestedcrop
biom
assorforage
DM
CO2
Dimensionless
Entity
Entry
BiomassCarbonStock
Changes
HarvestIndex
HI
CO2
Fraction
Default
Entry
Westetal.
(2010)
BiomassCarbonStock
Changes
Cropharvestor
forageyield,
correctedfor
moisturecontent
Y dm
CO2
Metrictons
biom
assha
‐1
Entity
Entry
BiomassCarbonStock
Changes
Approximate
fractionof
calendaryear
representingthe
grow
ingseason
Y f
CO2
Fraction
Entity
Entry
BiomassCarbonStock
Changes
Carbonfractionof
aboveground
biom
ass
CCO
2Fraction
Default
Entry
0.45
Normal
11.0
11.0
IPCC(1997)
CO2fromLiming
Annualapplication
oflime
M
CO2
Metrictons/
year
Entity
Entry
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
CO2fromLiming
MetrictonsCO2
emissionsper
metrictonsoflime
EF
CO2
Metrictons
C/metrictons
lime
Default
Entry
‐0.04
46.0
46.0
Westand
McBride
(2005)
CO2fromUreaFertilizer
Application
Annualamountof
ureafertilization
M
CO2
Metrictons
urea/year
Entity
Entry
CO2fromUreaFertilizer
Application
ProportionofCin
urea
EF
CO2
Metrictons
C/metrictons
urea
Default
Entry
0.2
deKleinet
al.(2006)
DirectN
2OEmissions
Areaoforganic
soils(histosols)
drainedona
parcelofland(ha)
Aos
N2O
ha
Entity
Entry
DirectN
2OEmissions
Prior‐yearcrop
type
N2O
MetrictonsN
year
‐1 ha‐1
Entity
Entry
DirectN
2OEmissions
Emissionrate
modeledat0level
ofNinput(Nt=0)
ER0
N2O
Metrictons
N2O‐Nha‐1 year‐
1
Model
Output
DirectN
2OEmissions
Emissionfactor
forthetypical
fertilizationrate
EFtypical
N2O
Metrictons
N2O‐Nmetric
tons
‐1N
Model
Output
DirectN
2OEmissions
TypicalNfertilizer
rate
Ntf
N2O
MetrictonsN
ha‐1year‐1
Database
DirectN
2OEmissions
Emissionratefor
thetypicalcase
modeled
ERtypical
N2O
MetrictonsN
ha‐1year‐1
Model
Output
DirectN
2OEmissions
ActualNfertilizer
rate,including
syntheticand
organic
Nf
N2O
MetrictonsN
year
‐1ha‐1
Entity
Entry
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
DirectN
2OEmissions
BaseEFscalarfor
ΔNf>zeroand
non‐grassland
crops
S EF
N2O
(metrictons
N2O‐N(metric
tonsN)‐2 )ha
year
Default
Entry
0.0274
Appendix3‐A
DirectN
2OEmissions
BaseEFscalarfor
ΔN=>zeroand
grassland
S EF
N2O
(metrictons
N2O‐N(metric
tonsN)‐2 )ha
year
Default
Entry
0.117
Appendix3‐A
DirectN
2OEmissions
BaseEFscalarfor
ΔNf<zero
S EF
N2O
(metrictons
N2O‐N(metric
tonsN)‐2 )ha
year
Default
Entry
0
Appendix3‐A
DirectN
2OEmissions
Drymatter
contentof
harvestedbiom
ass
DM
N2O
Entity
Entry
DirectN
2OEmissions
Residue:yield
ratios
N2O
Ratio
Entity
Entry
DirectN
2OEmissions
Amountofresidue
harvested,burned
orgrazed
Rr
N2O
Entity
Entry
DirectN
2OEmissions
Fractionoflive
biom
assremoved
bygrazing
F r
N2O
Entity
Entry
DirectN
2OEmissions
Nmineralization
from
manure
Nman
N2O
Entity
Entryand
Model
Output
DirectN
2OEmissions
Nmineralization
from
com
post
Ncomp
N2O
Entity
Entryand
Model
Output
DirectN
2OEmissions
Totaldrymatter
yieldofcrop
N2O
Metrictonsdry
matteryear
‐1
Entity
Entry
DirectN
2OEmissions
Stockingratesand
methods
N2O
Head/acre
Entity
Entry
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
DirectN
2OEmissions
Scalingfactorfor
slow
‐release
fertilizers,0where
noeffect
S sr
N2O
Dimensionless
Default
Entry
‐0.21
Normal
‐0.3
‐0.12Meta‐analysis
DirectN
2OEmissions
Scalingfactor
nitrification
inhibitors–sem
i‐arid/aridclimate
S inh
N2O
Dimensionless
Default
Entry
‐0.38
Normal
‐0.51
‐0.21Meta‐analysis
DirectN
2OEmissions
Scalingfactor
nitrification
inhibitors–mesic
climate
S inh
N2O
Dimensionless
Default
Entry
‐0.4
Normal
‐0.52
‐0.24Meta‐analysis
DirectN
2OEmissions
Scalingfactorfor
notill,sem
i‐arid/aridclimate,
<10years
followingno‐till
adoption
S till
N2O
Dimensionless
Default
Entry
0.38
0.04
0.72
vanKesselet
al.(2012);Six
etal.(2004)
DirectN
2OEmissions
Scalingfactorfor
notill,sem
i‐arid/aridclimate,
≥10years
followingno‐till
adoption
S till
N2O
Dimensionless
Default
Entry
‐0.33
‐0.5
‐0.16
vanKesselet
al.(2012);Six
etal.(2004)
DirectN
2OEmissions
Scalingfactorfor
notill,mesic/w
et
climate,<10years
followingno‐till
adoption
S till
N2O
Dimensionless
Default
Entry
‐0.015
‐0.16
0.16
vanKesselet
al.(2012);Six
etal.(2004)
DirectN
2OEmissions
Scalingfactorfor
notill,mesic/w
et
climate,≥10years
followingno‐till
adoption
S till
N2O
Dimensionless
Default
Entry
‐0.09
‐0.19
0.01
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al.(2012);Six
etal.(2004)
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
DirectN
2OEmissions
Ninslow‐release
Nfertilizerapplied
totheparcelof
land
Nsr
N2O
MetrictonsN
year
‐1ha‐1
Entity
Entry
DirectN
2OEmissions
Ninmanure
amendm
ents(and
sewagesludge)
addedtothe
parcel
Nman
N2O
MetrictonsN
year
‐1ha‐1
Entity
Entry
DirectN
2OEmissions
Nexcretedby
cattle,poultryand
swinedirectlyon
theparcelofland
(metrictonsN
year‐1ha‐1)
Nprp
N2O
MetrictonsN
year
‐1ha‐1
Entity
Entry
DirectandIndirectN
2O
Emissions
Ninsynthetic
fertilizerapplied
toaparcelofland
Nsfert
N2O
MetrictonsN
year
‐1ha‐1
Entity
Entry
DirectN
2OEmissions
Nfrom
achangein
soilorganicmatter
mineralizationdue
toLUCortillage
changeappliedto
aparcelofland
Nmin
N2O
MetrictonsN
year
‐1
Entity
Entry
DAYCEN
T
model
derived
DirectN
2OEmissions
Nfractionof
aboveground
biom
assforthe
croporforage
Na
N2O
Dimensionless
Entity
Entry
DirectN
2OEmissions
Nfractionof
belowground
biom
assforthe
croporforage
Nb
N2O
Dimensionless
Entity
Entry
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
IndirectN
2OEmissions
Emissionratefor
croppedhistosols,
EROS
N2O
Metrictons
N2O‐Nha‐1
year
‐1
Default
Entry
0.008
Uniform
0.002
0.02 4
IPCC(2006)
IndirectN
2OEmissions
Nfertilizerapplied
oforganicorigin
includingmanure,
sewagesludge,
compostandother
organic
amendm
ents
F ON
N2O
MetrictonsN
year
‐1
Entity
Entry
IndirectN
2OEmissions
FractionofNSN
thatvolatizesas
NH3andNOx
FRSN
N2O
kgNkg‐1 N
sfert
Default
Entry
0.1
Uniform
0.03
0.3
IPCC(2006)
IndirectN
2OEmissions
Fractionor
proportionofF
ON
thatvolatizesas
NH3andNOx
FRON
N2O
kgNkg‐1 N
ON
Default
Entry
0.2
Uniform
0.05
0.5
IPCC(2006)
IndirectN
2OEmissions
Emissionfactor
forvolatilizedNor
proportionofN
volatilizedasNH3
andNOxthatis
transformedto
N2Oinreceiving
ecosystem
EFvol
N2O
kgN
2O‐N
kg‐1N
Default
Entry
0.01
Uniform
0.002
0.05
IPCC(2006)
IndirectN
2OEmissions
Fractionor
proportionofNt
thatleachesor
runsoff
FRLeach
N2O
kgNkg‐1 N
Default
Entry
0.3
Uniform
0.1
0.8
IPCC(2006)
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
IndirectN
2OEmissions
Emissionfactor
forleachedand
runoffNor
proportionof
leachedandrunoff
Nthatis
transformedto
N2Oinreceiving
ecosystem
EFLeach
N2O
kgN
2O‐N
kg‐1N
Default
Entry
0.0075
Uniform
0.0005
0.02 5
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Cultivationperiod
forriceunderi,j,
andkconditions
t ijk
CH4
Days
Entity
Entry
Methanefrom
WetlandRice
Cultivation
Annualharvested
areaofricefori,j,
andkconditions
Aijk
CH4
Hectares/year
Entity
Entry
Methanefrom
WetlandRice
Cultivation
Applicationrateof
organic
amendm
ent(s)
ROAi
CH4
Metrictons/
hectare
Entity
Entry
Methanefrom
WetlandRice
Cultivation
Baselineem
ission
factorfor
continuously
floodedfields
withoutorganic
amendm
ents
EFc
CH4
kgCH4/ha/
day
Default
Entry
1.3
Uniform
0.8
2.2
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Waterregime
duringthe
cultivationperiod
–ScalingFactor
SFwfor
continuously
flooded
CH4
ScalingFactor
from
IPCC
Default
Entry
1
Uniform
0.79
1.26
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Waterregime
duringthe
cultivationperiod
–ScalingFactor
SFwforsingle
aeration
CH4
ScalingFactor
from
IPCC
Default
Entry
0.6
Uniform
0.46
0.8
IPCC(2006)
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CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Methanefrom
WetlandRice
Cultivation
Waterregime
duringthe
cultivationperiod
–ScalingFactor
SFwfor
multiple
aerations
CH4
ScalingFactor
from
IPCC
Default
Entry
0.52
Uniform
0.41
0.66
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Waterregime
beforethe
cultivationperiod
–Scalingfactor
SFpfornon‐
floodedpre‐
season<180
days
CH4
ScalingFactor
from
IPCC
Default
Entry
1
Uniform
0.88
1.14
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Waterregime
beforethe
cultivationperiod
–Scalingfactor
SFpfornon‐
floodedpre‐
season>180
days
CH4
ScalingFactor
from
IPCC
Default
Entry
0.68
Uniform
0.58
0.8
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Waterregime
beforethe
cultivationperiod
–Scalingfactor
SFpforflooded
pre‐season>
30days
CH4
ScalingFactor
from
IPCC
Default
Entry
1.9
Uniform
1.65
2.18
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Organic
amendm
entused
–scalingfactor
SFo
CH4
ScalingFactor
from
IPCC
Default
Entry
Methanefrom
WetlandRice
Cultivation
Organic
amendm
ent
conversionfactor
CFOAifor
straw
incorporation
lessthan30
daysbefore
cultivation
CH4
Conversion
factorfrom
IPCC
Default
Entry
1
Uniform
0.97
1.04
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Organic
amendm
ent
conversionfactor
CFOAifor
straw
incorporation
morethan30
daysbefore
cultivation
CH4
Conversion
factorfrom
IPCC
Default
Entry
0.29
Uniform
0.2
0.4
IPCC(2006)
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8-32
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Methanefrom
WetlandRice
Cultivation
Organic
amendm
ent
conversionfactor
CFOAifor
compost
CH4
Conversion
factorfrom
IPCC
Default
Entry
0.05
Uniform
0.01
0.08
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Organic
amendm
ent
conversionfactor
CFOAiforfarm
yardmanure
CH4
Conversion
factorfrom
IPCC
Default
Entry
0.14
Uniform
0.07
0.2
IPCC(2006)
Methanefrom
WetlandRice
Cultivation
Organic
amendm
ent
conversionfactor
CFOAifor
greenmanure
CH4
Conversion
factorfrom
IPCC
Default
Entry
0.5
Uniform
0.3
0.6
IPCC(2006)
MethaneUptakebySoils
PotentialCH4
Oxidationinsoils
PCH4for
grassland
CH4
kgCH4ha‐1
year
‐1
Default
Entry
3.2
Normal
0
6.9
DelGrossoet
al.(2000)
MethaneUptakebySoils
PotentialCH4
Oxidationinsoils
PCH4for
coniferous
forest
CH4
kgCH4ha‐1
year
‐1
Default
Entry
2.8
Normal
0.1
5.5
DelGrossoet
al.(2000)
MethaneUptakebySoils
PotentialCH4
Oxidationinsoils
PCH4for
deciduous
forest
CH4
kgCH4ha‐1
year
‐1
Default
Entry
11.8
Normal
1.9
21.6
DelGrossoet
al.(2000)
MethaneUptakebySoils
CH4oxidation
attenuationfactor:
croplandincluding
set‐aside(CRP)
grassland,grazing
land,andfertilized
orrecently
harvestedforests
AF
CH4
N/A
Default
Entry
0.30
Normal
0.07
1Sm
ithetal.
(2000)
MethaneUptakebySoils
CH4oxidation
attenuationfactor:
naturalvegetation,
0‐100yearsafter
abandonm
entof
agricultural
productionor
timberharvest
AF
CH4
N/A
Default
Entry
0.3+(0.007
×years
since
abandonm
ent)
Normal
0.07+
(0.007
×years
since
abando
nment)
1Sm
ithetal.
(2000)
C
hapt
er 8
: Unc
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8-33
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
MethaneUptakebySoils
CH4oxidation
attenuation
factor:>100years
post‐managem
ent
orneverusedfor
agricultural
managem
entor
timberharvest
AF
CH4
N/A
Default
Entry
1
Normal
0.07
1Sm
ithetal.
(2000)
N2Ofrom
WetlandRice
TotalNinputs
from
all
agronomic
sources:mineral
fertilizer,organic
amendm
ents,
residues,and
additional
mineralization
from
LUCortillage
change(metric
tonsNyear‐1 )
Nt
N2O
MetrictonsN
year
‐1
Entity
Entry
N2Ofrom
WetlandRice
FertilizerN
managem
ent
N2O
Rate
Entity
Entry
N2Ofrom
WetlandRice
Organicfertilizer
N
N2O
%N
Entity
Entry
N2Ofrom
WetlandRice
CropresidueN
N2O
%N
Entity
Entry
N2Ofrom
WetlandRice
Emissionfactoror
proportionofN
ttransformedto
N2O
EF
N2O
kgN
2O‐N
(kgN)‐1
Default
Entry
0.0022
Normal
0.2%
0.2%
Akiyamaet
al.(2005)
N2Ofrom
WetlandRice
Scalingfactorto
accountfor
drainageeffects
SFDfor
continuously
flooded
system
s
N2O
Dimensionless
Default
Entry
0
Akiyamaet
al.(2005)
Cha
pter
8: U
ncer
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ty A
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smen
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Qua
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Gre
enho
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Gas
Sou
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and
Sin
ks
8-34
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
N2Ofrom
WetlandRice
Scalingfactorto
accountfor
drainageeffects
SFDforaerated
system
sN2O
Dimensionless
Default
Entry
0.59
Normal
0.4%
0.4%
Akiyamaet
al.(2005)
NonCO2Emissions
BiomassBurn
BorealForest(all)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.34
Normal102%
102%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Wildfire
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.4
Normal340%
340%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Crow
nfire
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.43
Normal104%
104%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Surfacefire
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.15
Normal
96%
96%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Postloggingslash
burn
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.33
Normal130%
130%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Tem
perateForest
(all)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.45
Normal
51%
51%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Postloggingslash
burn
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.62
Normal264%
264%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Shrublands(all)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.72
Normal147%
147%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Callunahealth
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.71
Normal121%
121%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Fynbos
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.61
Normal195%
195%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Savanna
woodlands(early
dryseasonburns)
(all)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.4
Normal
93%
93%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Savanna
woodlands
(mid/latedry
seasonburns)(all)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.74
Normal
99%
99%
IPCC(2006)
C
hapt
er 8
: Unc
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8-35
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
NonCO2Emissions
BiomassBurn
Savannawoodland
(mid/late)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.72
Normal270%
270%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Tropicalsavanna
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.73
Normal598%
598%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Othersavanna
woodlands
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.68
Normal931%
931%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Savanna
grasslands(early
dryseasonburns)
(all)
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.74
Normal183%
183%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Tropical/sub‐
tropicalgrassland
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.74
Normal270%
270%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Tropical/sub‐
tropicalgrassland
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.92
Normal151%
151%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Tropicalpasture
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.35
Normal427%
427%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Savanna
Combustion
Efficiency(C)
CH4/N2O
Default
Entry
0.86
Normal
85%
85%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Emissionfactor
EFfor
grassland
CH4
gGHG/kg
burned
biom
ass
Default
Entry
2.3
Mean
Normal
8.0%
8.0%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Emissionfactor
EFforcrop
residue
CH4
gGHG/kg
burned
biom
ass
Default
Entry
2.7
Mean
Normal50.0%
50.0%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Emissionfactor
EFfor
grassland
N2O
gGHG/kg
burned
biom
ass
Default
Entry
0.21
Mean
Normal93.0%
93.0%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Emissionfactor
EFforcrop
residue
N2O
gGHG/kg
burned
biom
ass
Default
Entry
0.07
Mean
Normal50.0%
50.0%
IPCC(2006)
Cha
pter
8: U
ncer
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smen
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Gre
enho
use
Gas
Sou
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and
Sin
ks
8-36
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
NonCO2Emissions
BiomassBurn
Combustion
efficiency
Cfor
shrublands
CH4/N2O
%Burned
Default
Entry
0.72
Mean
Normal68.0%
68.0%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Combustion
efficiency
Cfor
grasslands
withearly
seasonburns
CH4/N2O
%Burned
Default
Entry
0.74
Mean
Normal50.0%
50.0%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Combustion
efficiency
Cfor
grasslands
withmidto
lateseason
burns
CH4/N2O
%Burned
Default
Entry
0.77
Mean
Normal66.0%
66.0%
IPCC(2006)
NonCO2Emissions
BiomassBurn
Combustion
efficiency
Cforsm
all
grains
CH4/N2O
%Burned
Default
Entry
0.9
Mean
Normal50.0%
50.0%
Expert
Assessm
ent
NonCO2Emissions
BiomassBurn
Combustion
efficiency
Cforlarge
grainandother
cropresidues
CH4/N2O
%Burned
Default
Entry
0.8
Mean
Normal50.0%
50.0%
Expert
Assessm
ent
NonCO2Emissions
BiomassBurn
Moisturecontent
ofresiduesand
forage
CH
4/N2O
%moisture
Default
Entry
NonCO2Emissions
BiomassBurn
Residuetoyield
ratioofcrop
R:Y
CH4/N2O
Metrictons
residue/
metrictonsdry
matteryield
Default
Entry
SOCChangeMineralSoils
SoilorganicC
stockattheendof
theyear
SOC t
CO2
MetrictonsC
ha‐1
Model
Output
DAYCEN
T
Model
derived
Ogleetal.
(2007);EPA
(2013)
C
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er 8
: Unc
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8-37
8-37
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
SOCChangeMineralSoils
SoilorganicC
stockatthe
beginningofthe
year
SOC t‐1
CO2
MetrictonsC
ha‐1
Model
Output
DAYCEN
T
Model
derived
Ogleetal.
(2007);EPA
(2013)
SOCChangeMineralSoils
Cropselectionand
RotationSequence
CO
2Managem
ent
ListDeveloped
byExperts
Entity
Entry
SOCChangeMineralSoils
Irrigation
applicationrate
CO
2Gallonsper
minute
Entity
Entry
SOCChangeMineralSoils
MineralFertilizer
applicationRate
CO
2lbs/squarefoot
Entity
Entry
SOCChangeMineralSoils
LimeAmendm
ent
applicationRate
CO
2lbs/squarefoot
Entity
Entry
SOCChangeMineralSoils
Organic
Amendm
ent
applicationRate
CO
2lbs/squarefoot
Entity
Entry
SOCChangeMineralSoils
Num
berofpasses
ineachoperation
CO
2Num
ber
Entity
Entry
SOCChangeMineralSoils
Depthofdrainage
CO
2Meters
Entity
Entry
SOCChangeMineralSoils
Lengthoffield
CO
2Meters
Entity
Entry
SOCChangeMineralSoils
HistoricalW
eather
Patterns
CO
2PRISM
WeatherData
Model
Output
SOCChangeMineralSoils
Physicaland
Chem
ical
PropertiesofSoil
CO
2NRCSSURRGO
database
Model
Output
SOCChangeMineralSoils–
GrazingLand
AnimalSizeused
forgrazing
CO
2lbs
Entity
Entry
Cha
pter
8: U
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Gre
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Gas
Sou
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and
Sin
ks
8-38
CroplandSub‐Source
Category
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
SOCChangeMineralSoils–
GrazingLand
StockingRate
CO
2Head/acre
Entity
Entry
SOCChangeMineralSoils–
GrazingLand
Irrigation
applicationrate
CO
2Gallonsper
minute
Entity
Entry
SOCChangeMineralSoils–
GrazingLand
MineralFertilizer
applicationRate
CO
2lbs/squarefoot
Entity
Entry
SOCChangeMineralSoils–
GrazingLand
Depthofdrainage
CO
2Meters
Entity
Entry
SOCChangeOrganicSoils
Emissionfactor
EFforcropland
incool
temperate
regions
CO2
MetrictonsC
ha‐1 year‐1
Default
Entry
11
Mean
Normal
45.0
45.0
Ogleetal.
(2003)
SOCChangeOrganicSoils
Emissionfactor
EFforcropland
inwarm
temperate
regions
CO2
MetrictonsC
ha‐1 year‐1
Default
Entry
14
Mean
Normal
35.0
35.0
Ogleetal.
(2003)
SOCChangeOrganicSoils
EmissionfactorEFforcropland
insubtropical
regions
CO2
MetrictonsC
ha‐1 year‐1
Default
Entry
14
Mean
Normal
46.0
46.0
Ogleetal.
(2003)
SOCChangeOrganicSoils
Emissionfactor
EFforgrazing
landincool
temperate
regions
CO2
MetrictonsC
ha‐1 year‐1
Default
Entry
2.8
Mean
Normal
45.0
45.0
Ogleetal.
(2003)
SOCChangeOrganicSoils
Emissionfactor
EFforgrazing
landinwarm
temperate
regions
CO2
MetrictonsC
ha‐1 year‐1
Default
Entry
3.5
Mean
Normal
35.0
35.0
Ogleetal.
(2003)
SOCChangeOrganicSoils
Emissionfactor
EFforgrazing
landin
subtropical
regions
CO2
MetrictonsC
ha‐1year‐1
Default
Entry
3.5
Mean
Normal
46.0
46.0
Ogleetal.
(2003)
C
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er 8
: Unc
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8-39
8-39
Table8‐B‐3:AnimalPopulationUncertaintyTem
plate
AnimalPopulationData
Elem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeUncertaintyLow(%)
RelativeUncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
NumberofAnimals
Beefreplacementheifers
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Dairyreplacementheifers
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Maturebeefcow
sN
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Steers(>500lbs)
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Bulls
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Stockers(All)
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Cattleonfeed
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Dairycow
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Cattle
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Americanbison
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
SheepNOF
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Feedlotsheep
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Goats
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Horses
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Mules/burros/asses
N
CH4,N2O
EntityEntry
‐1.0%
1.0%
ExpertAssessm
ent
Cha
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Gre
enho
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Gas
Sou
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and
Sin
ks
8-40
Table8‐B‐4:EntericFerm
entationandHousingUncertaintyTem
plate
DataElem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
DailyMilkProduction
Milk
CH4
kgmilk/animal/day
EntityEntry
3%
5%
Expert
Assessm
ent
Daysinmilk
DIM
CH4
Days
EntityEntry
Drymatterintake
DMI
CH4
kg/animal/day
EntityEntry
DailyWorkDonebyAnimal
Work
CH4
Hours/day
EntityEntry
Averagelivebodyweight–lactating
beefcow
sBW
CH4
kg
EntityEntry
BeefCow
MatureWeight
MW
CH4
lbs
EntityEntry
SteerDailyWeightGainto24months
WG
CH4
lbs/day
EntityEntry
BeefSteerMatureWeight
MW
CH4
lbs
EntityEntry
BeefHeiferMatureWeight
MW
CH4
lbs
EntityEntry
Netenergyrequiredbytheanimalfor
maintenance
NE m
CH4
MJday
‐1
EntityEntry
MilkFatContent
Fat
CH4
Percent
EntityEntry
StarchContentofDiet(DairyCow
s)
Starch
CH5
kg/animal/day
EntityEntry
AcidDetergentFiberContentofDiet
ADF
CH4
kg/head/day
EntityEntry
DE–EachFeedType
DE
CH4
Percentofgrossenergy
EntityEntry
NeutralDetergentFiberinDiet(Dairy
Cows)
NDF
CH4
Percent
EntityEntry
CrudeProteininDiet
CP
CH4
Percent
EntityEntry
AcidDetergentFiberContentofDiet
(DairyCow
s)
ADF
CH4
Percent
EntityEntry
NeutralDetergentFiberinDiet
NDF
CH4
Percent
EntityEntry
SupplementalFat(feedlot)
S.Fat
CH4
Percent
EntityEntry
3%
Mean
24
Expert
Assessm
ent
DietaryForage%
CH
4Percent
EntityEntry
TotalDigestibleNutrients(DairyCow
s)
TDN
CH4
kg
EntityEntry
YmFeedlot–AllRegions
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
YmBeefCattleNotonFeed(stocker)
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
Ym
BeefCattleNotonFeed(allforaging
animalsexceptdairy)
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
C
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8-41
8-41
DataElem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
YmDairyRepl.Heif.–California
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
YmDairyRepl.Heif.–West
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
Ym
DairyRepl.Heif.–NorthernGreat
Plains
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
YmDairyRepl.Heif.–Southcentral
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
YmDairyRepl.Heif.–Northeast
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
YmDairyRepl.Heif.–Midwest
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
YmDairyRepl.Heif.–Southeast
Ym
CH4
%GEconvertedtoCH4
DefaultEntry
Maximum
dailyemissionsfordairy
cows
E max
CH4
MJ/head
DefaultEntry
45.98
Millsetal.
(2003)
Averagelivebodyweightforlactating
cows
BW
N2O/NH3
kg
EntityEntry
TypicalAmmoniaLossesfrom
Dairy
HousingFacilities–Opendirtlots(cool,
humidregion)
NH3loss
N2O 3
PercentofN
ex
DefaultEntry
15%
30%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Dairy
HousingFacilities–Opendirtlots(hot,
aridregion)
NH3loss
N2O
PercentofN
ex
DefaultEntry
30%
45%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Dairy
HousingFacilities–Roofedfacility
(flushedorscraped)
Roofedfacility(dailyscrapeandhaul)
NH3loss
N2O
PercentofN
ex
DefaultEntry
5%
15%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Dairy
HousingFacilities–Roofedfacility
(shallowpitunderfloor)
NH3loss
N2O
PercentofN
ex
DefaultEntry
10%
20%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Dairy
HousingFacilities–Roofedfacility
(beddedpack)
NH3loss
N2O
PercentofN
ex
DefaultEntry
20%
40%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Dairy
HousingFacilities–Roofedfacility
(deeppitunderfloor,includesstorage
loss)
NH3loss
N2O
PercentofN
ex
DefaultEntry
30%
40%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Beef
HousingFacilities–Opendirtlots(cool,
humidregion)
NH3loss
N2O
PercentofN
ex
DefaultEntry
30%
45%
Koelshand
Stow
ell
(2005)
Cha
pter
8: U
ncer
tain
ty A
sses
smen
t for
Qua
ntify
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Gre
enho
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Gas
Sou
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and
Sin
ks
8-42
DataElem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
TypicalAmmoniaLossesfrom
Beef
HousingFacilities–Opendirtlots(hot,
aridregion)
NH3loss
N2O
PercentofN
ex
DefaultEntry
40%
60%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Beef
HousingFacilities–Roofedfacility
(beddedpack)
NH3loss
N2O
PercentofN
ex
DefaultEntry
20%
40%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Beef
HousingFacilities–Roofedfacility
(deeppitunderfloor,includesstorage
loss)
NH3loss
N2O
PercentofN
ex
DefaultEntry
30%
40%
Koelshand
Stow
ell
(2005)
N2OEmissionFactorformanurein
housing(drylotsandpitstorage)
EFN2O
N2O
kgN
2O‐N/kgN
DefaultEntry
IPCC(2006)
NitrogenExcretionfrom
BeefCattle—
Daysonfeedforanindividualration
DOF x
N2O,NH3
Days
EntityEntry
NitrogenExcretionfrom
BeefCattle—
Livebodyweightatfinishoffeeding
period
BW
FN
2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
BeefCattle—
Livebodyweightatthestartoffeeding
period
BW
IN
2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
BeefCattle—
Standardreferenceweightforexpected
finalbodyfat
SRW
N2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
BeefCattle—
Concentrationofcrudeproteinoftotal
ration
C CP‐x
N2O,NH3
gcrudeprotein/gdry
feed
EntityEntry
MonthlyBeefFeedlotNH3Emissions—
Dietarycrudeprotein
CP
NH3
Percentofdrymatter
EntityEntry
Averagemonthlytemperature
T
N2O,NH3
DegreesKelvin
EntityEntry
NitrogenExcretionfrom
Grow‐Finish
Pigs–Averagedailyfeedintakeover
finishingperiod
ADFI
G
N2O,NH3
g/day
EntityEntry
NitrogenExcretionfrom
Grow‐Finish
Pigs–Concentrationofcrudeproteinof
total(wet)ration
C CP
N2O,NH3
Percent
EntityEntry
C
hapt
er 8
: Unc
erta
inty
Ass
essm
ent f
or Q
uant
ifyin
g G
reen
hous
e G
as S
ourc
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nd S
inks
8-43
8-43
DataElem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
NitrogenExcretionfrom
Grow‐Finish
Pigs–Daysonfeedtofinishanimal
(grow‐finishphase)
DOF G
N2O,NH3
Days
EntityEntry
NitrogenExcretionfrom
Grow‐Finish
Pigs–Final(market)bodyweight
BW
FN2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
Grow‐Finish
Pigs–Averagedressingpercent(yield)
atfinalw
eight
DP F
N2O,NH3
Percent
EntityEntry
NitrogenExcretionfrom
Grow‐Finish
Pigs–Initialbodyweight
BW
IN2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
Grow‐Finish
Pigs–Averagefat‐freeleanpercentage
atfinalw
eight
FFLP
FN2O,NH3
Percent
EntityEntry
NitrogenExcretionfrom
WeaningPigs–
Averagedailyfeedintakeoverfinishing
period
ADFI
G
N2O,NH3
g/day
EntityEntry
NitrogenExcretionfrom
WeaningPigs–
Concentrationofcrudeproteinoftotal
(wet)ration
C CP
N2O,NH3
Percent
EntityEntry
NitrogenExcretionfrom
WeaningPigs–
Daysonfeedtofinishanimal(nursery
phase)
DOF N
N2O,NH3
Days
EntityEntry
NitrogenExcretionfrom
WeaningPigs–
Averagefat‐freeleangainfrom
20to
120kg
FFLPG
N2O,NH3
g/day
EntityEntry
NitrogenExcretionfrom
WeaningPigs–
Finalbodyweightinnurseryphase
BW
F‐N
N2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
WeaningPigs–
Initialbodyweightinnurseryphase
BW
I‐N
N2O,NH3
kg
EntityEntry
NitrogenExcretionfrom
GestatingSow
s–Averagedailyfeedintakeduring
gestation
ADFI
SN2O,NH3
g/day
EntityEntry
NitrogenExcretionfrom
GestatingSow
s–Concentrationofcrudeprotein
C CP
N2O,NH3
Percent
EntityEntry
NitrogenExcretionfrom
GestatingSow
s–Gestationperiodlength
GL
N2O,NH3
Days
EntityEntry
NitrogenExcretionfrom
GestatingSow
s–Gestationleantissuegain
GLTG
N2O,NH3
Kg
EntityEntry
Cha
pter
8: U
ncer
tain
ty A
sses
smen
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Gre
enho
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Gas
Sou
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and
Sin
ks
8-44
DataElem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
NitrogenExcretionfrom
GestatingSow
s–Num
berofpigsinlitter
LITTERN2O,NH3
Head
EntityEntry
NitrogenExcretionfrom
Lactating
Sows—
Averagedailyfeedintakeduring
lactation
ADFI
LACT
N2O,NH3
g/day
EntityEntry
NitrogenExcretionfrom
Lactating
Sows—
Concentrationofcrudeprotein
C CP
N2O,NH3
Percent
EntityEntry
NitrogenExcretionfrom
Lactating
Sows—
Lactationlength(daysto
weaning)
LL
N2O,NH3
Days
EntityEntry
NitrogenExcretionfrom
Lactating
Sows—
Lactationleantissuegain
LLTG
N2O,NH3
Kg
EntityEntry
NitrogenExcretionfrom
Lactating
Sows—
Litterweightatw
eaning
L WEAN
N2O,NH3
Kg
EntityEntry
NitrogenExcretionfrom
Lactating
Sows—
Litterweightatbirth
LWBIRTHN2O,NH3
kg
EntityEntry
TypicalAmmoniaLossesfrom
Swine
HousingFacilities–Roofedfacility
(flushedorscraped)Roofedfacility
(dailyscrapeandhaul)
%NH3
loss
NH3
PercentofN
ex
DefaultEntry
5%
15%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Swine
HousingFacilities–Roofedfacility
(shallowpitunderfloor)
%NH3
loss
NH3
PercentofN
ex
DefaultEntry
10%
20%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Swine
HousingFacilities–Roofedfacility
(beddedpack)
%NH3
loss
NH3
PercentofN
ex
DefaultEntry
20%
40%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Swine
HousingFacilities–Roofedfacility
(deeppitunderfloor,includesstorage
loss)
%NH3
loss
NH3
PercentofN
ex
DefaultEntry
30%
40%
Koelshand
Stow
ell
(2005)
NitrogenExcretionfrom
Broilers,
Turkeys,andDucks—Feedintakeper
phase
FIx
N2O,NH3
gfeed/finishedanimal
EntityEntry
NitrogenExcretionfrom
Broilers,
Turkeys,andDucks—Concentrationof
crudeproteinoftotalrationineach
phase
C CP‐X
N2O,NH3
gcrudeprotein/g(wet)
feed
EntityEntry
C
hapt
er 8
: Unc
erta
inty
Ass
essm
ent f
or Q
uant
ifyin
g G
reen
hous
e G
as S
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nd S
inks
8-45
8-45
DataElem
entNam
e
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
NitrogenExcretionfrom
Broilers,
Turkeys,andDucks—Retentionfactor
fornitrogen
NRF
N2O,NH3
Fraction
EntityEntry
NitrogenExcretionfrom
LayingHens—
Feedintake
FI
N2O,NH3
gfeed/finishedanimal
EntityEntry
NitrogenExcretionfrom
LayingHens—
Concentrationofcrudeproteinoftotal
ration
C CP
N2O,NH3
gcrudeprotein/g(wet)
feed
EntityEntry
NitrogenExcretionfrom
LayingHens—
Eggweight
Egg w
tN2O,NH3
gEntityEntry
NitrogenExcretionfrom
LayingHens—
Fractionofeggsproducedeachday
Egg p
ro
N2O,NH3
Eggs/hen/day
EntityEntry
TypicalAmmoniaLossesfrom
Poultry
Housing–Roofedfacility(litter)(Meat
Producingbirds)
%NH3
loss
NH3
PercentofN
ex
DefaultEntry
25%
50%
Koelshand
Stow
ell
(2005)
TypicalAmmoniaLossesfrom
Poultry
Housing–Roofedfacility(stacked
manureunderfloor‐,includesstorage
loss)(Egg‐producingbirds)
%NH3
loss
NH3
PercentofN
ex
DefaultEntry
25%
50%
Koelshand
Stow
ell
(2005)
MethaneEmissionsfrom
Goats–
Emissionfactorforgoats
EFG
CH4
kgCH4/head/day
DefaultEntry
0.0137
Mean
IPCC(2006)
MethaneEmissionsfrom
Bison–
Emissionfactorforbison
EFAB
CH4
kgCH4/head/day
DefaultEntry
Cha
pter
8: U
ncer
tain
ty A
sses
smen
t for
Qua
ntify
ing
Gre
enho
use
Gas
Sou
rces
and
Sin
ks
8-46
Table8‐B‐5:M
anureManagem
entUncertaintyTem
plate
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
TotalDryManure–BeefFinishingCattle
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
2.4
Mean
‐20
20
ASABE(2005)
TotalDryManure–BeefCow
(confinem
ent)
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
6.6
Mean
‐20
20
ASABE(2005)
TotalDryManure–BeefGrowingcalf
(confinem
ent)
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
2.7
Mean
‐20
20
ASABE(2005)
TotalDryManure–DairyLactatingcow
CH4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
8.9
Mean
‐20
20
8.7
11.3
ASABE(2005)
TotalDryManure–DairyDrycow
CH4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
4.9
Mean
‐20
20
8.8
11.2
ASABE(2005)
TotalDryManure–DairyHeifer
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
3.7
Mean
‐20
20
ASABE(2005)
TotalDryManure–DairyVeal118kg
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.12
Mean
‐20
20
ASABE(2005)
TotalDryManure–HorseSedentary500
kg
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
3.8
Mean
‐20
20
ASABE(2005)
TotalDryManure–HorseIntense
exercise500kg
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
3.9
Mean
‐20
20
ASABE(2005)
TotalDryManure–PoultryBroiler
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.03
Mean
‐20
20
ASABE(2005)
TotalDryManure–PoultryTurkey(male)
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.07
Mean
‐20
20
ASABE(2005)
TotalDryManure–PoultryTurkey
(fem
ales)
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.04
Mean
‐20
20
ASABE(2005)
TotalDryManure–PoultryDuck
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.04
Mean
‐20
20
ASABE(2005)
TotalDryManure–Layer
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.02
Mean
‐20
20
ASABE(2005)
TotalDryManure–Sw
ineNurserypig
(12.5kg)
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.13
Mean
‐20
20
ASABE(2005)
TotalDryManure–Sw
ineGrowfinish(70
kg)
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.47
Mean
‐20
20
ASABE(2005)
TotalDryManure–Sw
inegestatingsow
200kg
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.5
Mean
‐20
20
ASABE(2005)
C
hapt
er 8
: Unc
erta
inty
Ass
essm
ent f
or Q
uant
ifyin
g G
reen
hous
e G
as S
ourc
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nd S
inks
8-47
8-47
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
TotalDryManure–Sw
ineLactatingsow
192kg
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
1.2
Mean
‐20
20
ASABE(2005)
TotalDryManure–Sw
ineBoar200kg
CH
4,N2O,
NH3
kgdry
manure/animal/day
EntityEntry
0.38
Mean
‐20
20
ASABE(2005)
Volatilesolids–BeefFinishingcattle
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.81
Mean
‐25
25
ASABE(2005)
Volatilesolids–BeefCow(confinem
ent)
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.89
Mean
‐25
25
ASABE(2005)
Volatilesolids–BeefGrowingcalf
(confinem
ent)
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.85
Mean
‐25
25
ASABE(2005)
Volatilesolids–DairyLactatingcow
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.84
Mean
‐25
25
ASABE(2005)
Volatilesolids–DairyDrycow
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.85
Mean
‐25
25
ASABE(2005)
Volatilesolids–DairyHeifer
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.86
Mean
‐25
25
ASABE(2005)
Volatilesolids–DairyVeal118kg
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
Mean
‐25
25
ASABE(2005)
Volatilesolids–HorseSedentary500kg
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.79
Mean
‐25
25
ASABE(2005)
Volatilesolids–HorseIntenseexercise
500kg
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.79
Mean
‐25
25
ASABE(2005)
Volatilesolids–PoultryBroiler
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.73
Mean
‐25
25
ASABE(2005)
Volatilesolids–PoultryTurkey(male)
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.8
Mean
‐25
25
ASABE(2005)
Volatilesolids–PoultryTurkey(fem
ales)
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.79
Mean
‐25
25
ASABE(2005)
Volatilesolids–PoultryDuck
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.58
Mean
‐25
25
ASABE(2005)
Volatilesolids–Layer
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.73
Mean
‐25
25
ASABE(2005)
Volatilesolids–Sw
ineNurserypig(12.5
kg)
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.83
Mean
‐25
25
ASABE(2005)
Volatilesolids–Sw
ineGrowfinish(70kg)
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.8
Mean
‐25
25
ASABE(2005)
Volatilesolids–Sw
inegestatingsow
200
kg
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.9
Mean
‐25
25
ASABE(2005)
Volatilesolids–Sw
ineLactatingsow
192
kg
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.83
Mean
‐25
25
ASABE(2005)
Volatilesolids–Sw
ineBoar200kg
VS
CH4,N2O
kgVS/kgdrymanure
EntityEntry
0.89
Mean
‐25
25
ASABE(2005)
Storagetemperature
T
CH4
Kelvin
EntityEntry
Manuretemperature
Tmanure
NH3
Kelvin
EntityEntry
Ambientairvelocity
Va
NH3
m/s
DefaultEntry
Height
hN2O
m
EntityEntry
Width
W
NH3
m
EntityEntry
Radius
rNH3
m
EntityEntry
pH
pH
NH3
‐EntityEntry
7.5
6.5
8.5
Expert
Assessm
ent
Cha
pter
8: U
ncer
tain
ty A
sses
smen
t for
Qua
ntify
ing
Gre
enho
use
Gas
Sou
rces
and
Sin
ks
8-48
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Totalnitrogenatagivenday–beef
finishingcattle
N2O
kgN/kgdrymanure
EntityEntry
0.07
Mean
ASABE(2005)
Totalnitrogenatagivenday–beefcow
(confinem
ent)
N2O
kgN/kgdrymanure
EntityEntry
0.03
Mean
ASABE(2005)
Totalnitrogenatagivenday–beef
grow
ingcalf(confinem
ent)
N2O
kgN/kgdrymanure
EntityEntry
0.05
Mean
ASABE(2005)
Totalnitrogenatagivenday–dairy
lactatingcow
N2O
kgN/kgdrymanure
EntityEntry
0.05
Mean
ASABE(2005)
Totalnitrogenatagivenday–dairydry
cow
N2O
kgN/kgdrymanure
EntityEntry
0.05
Mean
ASABE(2005)
Totalnitrogenatagivenday–dairyheifer
N2O
kgN/kgdrymanure
EntityEntry
0.03
Mean
ASABE(2005)
Totalnitrogenatagivenday–dairyveal
118kg
N2O
kgN/kgdrymanure
EntityEntry
0.13
Mean
ASABE(2005)
Totalnitrogenatagivenday–Horse
Sedentary500kg
N2O
kgN/kgdrymanure
EntityEntry
0.02
Mean
ASABE(2005)
Totalnitrogenatagivenday–Horse
IntenseExercise
N2O
kgN/kgdrymanure
EntityEntry
0.04
Mean
ASABE(2005)
Totalnitrogenatagivenday–poultry,
broiler
N2O
kgN/kgdrymanure
EntityEntry
0.04
Mean
ASABE(2005)
Totalnitrogenatagivenday–poultry,
turkey(male)
N2O
kgN/kgdrymanure
EntityEntry
0.06
Mean
ASABE(2005)
Totalnitrogenatagivenday–poultry,
turkey(females)
N2O
kgN/kgdrymanure
EntityEntry
0.06
Mean
ASABE(2005)
Totalnitrogenatagivenday–poultry,
duck
N2O
kgN/kgdrymanure
EntityEntry
0.04
Mean
ASABE(2005)
Totalnitrogenatagivenday–layer
N2O
kgN/kgdrymanure
EntityEntry
0.07
Mean
ASABE(2005)
Totalnitrogenatagivenday–swine
nurserypig(12.5kg)
N2O
kgN/kgdrymanure
EntityEntry
0.09
Mean
ASABE(2005)
Totalnitrogenatagivenday–swinegrow
finish(70kg)
N2O
kgN/kgdrymanure
EntityEntry
0.08
Mean
ASABE(2005)
Totalnitrogenatagivenday–swine
gestatingsow200kg
N2O
kgN/kgdrymanure
EntityEntry
0.06
Mean
ASABE(2005)
Totalnitrogenatagivenday–swine
lactatingsow192kg
N2O
kgN/kgdrymanure
EntityEntry
0.07
Mean
ASABE(2005)
Totalnitrogenatagivenday–swineboar
200kg
N2O
kgN/kgdrymanure
EntityEntry
0.07
Mean
ASABE(2005)
Totalammonianitrogeninthemanure–
beefearthenlot
TAN
NH3
kgNH3/m
3 EntityEntry
0.1
Mean
00.02
ASABE(2005)
C
hapt
er 8
: Unc
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inty
Ass
essm
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or Q
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8-49
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Totalammonianitrogeninthemanure–
poultry,leghornpullets
TAN
NH3
kgNH3/m
3 EntityEntry
0.85
Mean
0.66
1.04
ASABE(2005)
Totalammonianitrogeninthemanure–
poultry,leghornhen
TAN
NH3
kgNH3/m
3 EntityEntry
0.88
Mean
0.54
1.22
ASABE(2005)
Totalammonianitrogeninthemanure–
poultry,broiler
TAN
NH3
kgNH3/m
3 EntityEntry
0.75
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
dairylagooneffluent
NH3
NH3
kgNH3/m
3 Calculated
0.08
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
dairyslurry(liquid)
NH3
NH3
kgNH3/m
3 Calculated
0.14
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
SwineFinisher‐Slurrywet‐dryfeeders
NH3
NH3
kgNH3/m
3 Calculated
0.5
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
SwineSlurrystorage‐dryfeeders
NH3
NH3
kgNH3/m
3 Calculated
0.34
Mean
0.19
0.49
ASABE(2005)
Ammoniaconcentrationintheliquid–
Swineflushbuilding
NH3
NH3
kgNH3/m
3 Calculated
0.14
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
Swineagitatedsolidsandwater
NH3
NH3
kgNH3/m
3 Calculated
0.05
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
SwineLagoonsurfacewater
NH3
NH3
kgNH3/m
3 Calculated
0.04
Mean
ASABE(2005)
Ammoniaconcentrationintheliquid–
SwineLagoonsludge
NH3
NH3
kgNH3/m
3 Calculated
0.07
Mean
ASABE(2005)
MethaneConversionFactor(MCF)a–Dairy
Cow
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Cattle
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Buffalo
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Market
Swine
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a–Breeding
Swine
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactora–Layer(Dry)
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a–Broiler
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a–Turkey
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Duck
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Sheep
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Goat
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Horse
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Mule/Ass
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
Cha
pter
8: U
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tain
ty A
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smen
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Qua
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Gre
enho
use
Gas
Sou
rces
and
Sin
ks
8-50
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
MethaneConversionFactor
a –Buffalo
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Invessel
manurecomposting
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a–Staticpile
manurecomposting
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Intensive
windrow
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
MethaneConversionFactor
a –Passive
windrow
MCF
CH4
%
DefaultEntry
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
BeefReplacementHeifers
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.33
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
DairyReplacementHeifers
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.17
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
MatureBeefCow
sBo
CH4
m3 CH
4/kgVS
DefaultEntry
0.33
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
Steers(>500lbs)
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.33
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
Stockers(All)
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.17
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
CattleonFeed
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.33
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
DairyCow
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.24
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
Cattle
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.19
‐20
20
U.S.EPA
(2011)
Maximum
MethaneProducingCapacities–
Buffalo
b Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.1
IPCC(2006)
Maximum
MethaneProducingCapacities–
MarketSwine
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.48
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
BreedingSw
ine
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.48
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Layer(dry)
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.39
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Layer(wet)
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.39
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Broiler
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.36
‐30
30
IPCC(2006)
C
hapt
er 8
: Unc
erta
inty
Ass
essm
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or Q
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ifyin
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nd S
inks
8-51
8-51
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Maximum
MethaneProducingCapacities–
Turkey
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.36
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Duck
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.36
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Sheep
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.19
‐20
20
IPCC(2006)
Maximum
MethaneProducingCapacities–
Feedlotsheep
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.36
‐20
20
IPCC(2006)
Maximum
MethaneProducingCapacities–
Goat
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.17
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Horse
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.3
‐30
30
IPCC(2006)
Maximum
MethaneProducingCapacities–
Mule/Ass
Bo
CH4
m3 CH
4/kgVS
DefaultEntry
0.33
‐30
30
IPCC(2006)
EmissionfactorforthefractionofCH4
producedthatleaksfrom
theanaerobic
digester–Digesterswithsteelorlined
concreteorfiberglassdigesterswithagas
holdingsystem
(eggshapeddigesters)and
monolithicconstruction
EFCH
4,
leakage
CH4
%
DefaultEntry
2.8
CDM(2012)
EmissionfactorforthefractionofCH4
producedthatleaksfrom
theanaerobic
digester–UASBtypedigesterswith
floatinggasholdersandnoexternalw
ater
seal
EFCH
4,
leakage
CH4
%
DefaultEntry
5
CDM(2012)
EmissionfactorforthefractionofCH4
producedthatleaksfrom
theanaerobic
digester–Digesterswithunlined
concrete/ferrocement/brickmasonry
archedtypegasholdingsection;
monolithicfixeddomedigesters
EFCH
4,
leakage
CH4
%
DefaultEntry
10
CDM(2012)
EmissionfactorforthefractionofCH4
producedthatleaksfrom
theanaerobic
digester–Otherdigesterconfigurations
EFCH
4,
leakage
CH4
%
DefaultEntry
10
CDM(2012)
Tem
porarystorageofliquid/slurry
manure–N
2Oemissionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.005
‐50
100
U.S.EPA
(2011)
Long‐termstorageofsolidmanure–N
2O
emissionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.002
‐50
100
U.S.EPA
(2011)
Cha
pter
8: U
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tain
ty A
sses
smen
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Qua
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ing
Gre
enho
use
Gas
Sou
rces
and
Sin
ks
8-52
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Long‐termstorageofslurrymanure–N2O
emissionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.005
‐50
100
U.S.EPA
(2011)
CattleandSwineDeepBedding(Active
Mix)‐N
2Oemissionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.07
IPCC(2006)
CattleandSwineDeepBedding(NoMix)‐
N2Oemissionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.01
IPCC(2006)
PitStorageBelow
AnimalConfinem
ents‐
N2Oemissionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.002
IPCC(2006)
Naturalaerationaerobiclagoons–N2O
conversionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.01
‐50
100
IPCC(2006)
Forcedaerationaerobiclagoons–N2O
conversionfactor
c EF
N20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.005
‐50
100
IPCC(2006)
N2Oemissionfactorforliquidstorage–
uncoveredliquidmanurewithacrustc
EFN20
N2O
kgN
2O‐N/kgN
DefaultEntry
0.8
‐50
100
IPCC(2006)
N2Oemissionfactorforliquidstorage–
uncoveredliquidmanurewithoutacrustc
EFN20
N2O
kgN
2O‐N/kgN
DefaultEntry
0
‐50
100
IPCC(2006)
N2Oemissionfactorforliquidstorage–
coveredliquidmanurec
EFN20
N2O
kgN
2O‐N/kgN
DefaultEntry
0
‐50
100
IPCC(2006)
Composting–Ammoniaemission(loss)
relativetototalnitrogeninmanure
EFNH3
NH3
kgNH3‐N/kgN
DefaultEntry
0.05
Hellebrand
andKalk
(2000)
ManureManagem
ent–MultipleSources–
collectionefficiency,coveredstorage(with
orwithoutcrust)
ηCH
4percentage
DefaultEntry
1
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
collectionefficiency,uncoveredstorage
withcrustformation
ηCH
4percentage
DefaultEntry
0
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
collectionefficiency,uncoveredstorage
withoutcrustform
ation
ηCH
4percentage
DefaultEntry
‐0.40
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
Ratecorrectingfactors(b
1)
b 1
CH4
dimensionless
DefaultEntry
1
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
Ratecorrectingfactors(b
2)
b 2
CH4
dimensionless
DefaultEntry
0.01
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
Arrheniusparam
eter,cattle
A
CH4
gCH
4/kgVS/hr
DefaultEntry
43.33
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
Arrheniusparam
eter,swine
A
CH4
gCH
4/kgVS/hr
DefaultEntry
43.21
Sommeretal.
(2004)
C
hapt
er 8
: Unc
erta
inty
Ass
essm
ent f
or Q
uant
ifyin
g G
reen
hous
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as S
ourc
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nd S
inks
8-53
8-53
DataElem
entNam
e
DataElementAbbreviation/Symbol
EmissionType
DataInputUnit
InputType
EstimatedValue
TypeofEstimate
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
Potentialm
ethaneyieldofthemanure
cattle
E CH4,pot‐
CH4
kgCH4/kgVS
DefaultEntry
0.48
Sommeretal.
(2004)
Potentialm
ethaneyieldofthemanure‐
swine
E CH4,pot
CH4
kgCH4/kgVS
DefaultEntry
0.5
Sommeretal.
(2004)
ManureManagem
ent–MultipleSources–
Kinem
aticviscosityofaire
vNH3
m2 /s
DefaultEntry
White(1999)
ManureManagem
ent–MultipleSources–
MassdiffusivityofNH3e
D
NH3
m2 /s
DefaultEntry
Watson
(1966)and
Baker(1969)
Tem
porarystackandlong‐termstockpile–
Resistancetomasstransferthroughthe
manuree
Rs
NH3
s/m
DefaultEntry
Rotzetal.
(2011)
Tem
porarystackandlong‐termstockpile–
Resistancetomasstransferthroughthe
covere
Rc
NH3
s/m
DefaultEntry
Rotzetal.
(2011)
Tem
porarystackandlong‐termstockpile–
Ratiodegradablevolatilesolidstototal
volatilesolids‐cattleliquidmanure
VS d/VS T
CH4
Unitless
DefaultEntry
0.46
Mølleretal.
(2004)
Tem
porarystackandlong‐termstockpile–
Ratiodegradablevolatilesolidstototal
volatilesolids‐swineliquidmanure
VS d/VS T
CH4
Unitless
DefaultEntry
0.89
Mølleretal.
(2004)
Tem
porarystackandlong‐termstockpile–
RatioNon‐degradablevolatilesolidsto
totalvolatilesolids‐cattleliquidmanure
VS n
d/VS
T
CH4
Unitless
DefaultEntry
0.54
Mølleretal.
(2004)
Tem
porarystackandlong‐termstockpile–
Rationon‐degradablevolatilesolidsto
totalvolatilesolids–swineliquidmanure
VS n
d/VS
T
CH4
Unitless
DefaultEntry
0.11
Mølleretal.
(2004)
Solid‐liquidseparation–Efficiencyof
mechanicalsolid‐liquidseparation
e
CH4,N2O,
NH3
Percent
EntityEntry
Fordand
Flem
ing
(2002)
a Thevaluesformethaneconversionfactor(MCF)varydependingonthetemperatureandthemanuremanagem
entsystem.IPCC(2006)providesestimateduncertainty
rangesfortheseMCFs.
b TherearenodataforNorthAmericaregion;thedatafrom
WesternEuropeareusedtocalculatetheestimation.Thereisnoreporteduncertaintyforthisadaptedvalue.
c IPCC(2006)reportslargeuncertaintieswithdefaultN
2Oemissionfactors.TheN
2OEFvaluesvarydependingontheanimalspeciesandtemperatureofthemanure
managem
entsystem.
d ValuesforN2Oconversionfactorsareavailablefordairycow,cattle,swine,andotheranimalsandcanbefoundinthechapter.
e Defaultvaluesareavailableinthechapter.
Cha
pter
8: U
ncer
tain
ty A
sses
smen
t for
Qua
ntify
ing
Gre
enho
use
Gas
Sou
rces
and
Sin
ks
8-54
Table8‐B‐6:ForestryUncertaintyTable
ForestrySub‐
SourceCategory
DataElementName
Abbreviation/Symbol
EmissionType
DataInputUnit
InputSource
Statistic
TypeofStatistic
ProbabilityDistributionType
RelativeuncertaintyLow(%)
RelativeuncertaintyHigh(%)
ConfidenceLevel(%)
EffectiveLowerLimit
EffectiveUpperLimit
DataSource
UrbanForestry–
AerialDataMethod
TreeCover
Percent
CO
2%
Model
Output
i‐TreeCanopy
UrbanForestry–
AerialDataMethod
UrbanArea
CO
2m
2 Entity
Entry
UrbanForestry–
AerialDataMethod
Average
Annual
Carbon
Sequestration
CO
2kg
C/m
2 /yearDefault
Entry
2.8
mean
14.814.8
Now
aketal.(2013)
UrbanForestry–
AerialDataMethod
Average
Carbon
Storage
CO
2kgC/m
2 Default
Entry
7.69
mean
Now
aketal.(2013)
Chapter 8: Uncertainty Assessment for Quantifying Greenhouse Gas Sources and Sinks
8-55
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Ford,M.,andR.Fleming.2002.MechnicalSolid‐LiquidSeparationofLivestockManureLiteratureReview:UniversityofGuelph.
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