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Agricultural mitigation and adaptation to climate change in Yolo County, CA

Authors:
ADAPTATIONSTRATEGIESFOR
AGRICULTURALSUSTAINABILITYIN
YOLOCOUNTY,CALIFORNIA
AWhitePaperfromtheCaliforniaEnergyCommission’sCaliforniaClimateChangeCenter
JULY2012
CEC5002012032
Preparedfor:CaliforniaEnergyCommission
Preparedby:UniversityofCalifornia,Davis
LouiseJackson
VanR.Haden
AllanD.Hollander
HyunokLee
MarkLubell
VishalK.Mehta
TobyO’Geen
MeredithNiles
JoshPerlman
DavidPurkey
WilliamSalas
DanSumner
MihaelaTomuta
MichaelDempsey
StephenM.Wheeler
UniversityofCalifornia,Davis
DISCLAIMER
This paper was prepared as the result of work sponsored by the California Energy Commission. It
does not necessarily represent the views of the Energy Commission, its employees or the State of
California. The Energy Commission, the State of California, its employees, contractors and
subcontractors make no warrant, express or implied, and assume no legal liability for the information
in this paper; nor does any party represent that the uses of this information will not infringe upon
privately owned rights. This paper has not been approved or disapproved by the California Energy
Commission nor has the California Energy Commission passed upon the accuracy or adequacy of
the information in this paper.
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ACKNOWLEDGEMENTS
Wegreatlyappreciatetheinvolvementofoursteeringcommitteeinmanyaspectsofthis
project:JohnYoung(YoloCountyAgriculturalCommissioner),ChuckDudley(Presidentofthe
YoloCountyFarmBureau),JohnMottSmith(YoloCountyClimateChangeCoordinator),
HasanBolkan(CampbellSoup),andTonyTurkovich,andJimandDeborahDurst(farmersin
YoloCounty).TheUniversityofCaliforniaCooperativefarmadvisorsofYoloCountyprovided
muchinformationandsupport(GeneMiyao,RachelLong,andCountyDirector,KentBrittan).
WewouldliketothankTimO’Halloran,MaxStevenson,andthestaffoftheYoloCountyFlood
ControlandWaterConservationDistrictfortheirgenerouscontributionsofdata,time,and
insight.Fortheassessmentofagriculturalgreenhousegasemissions,wearegratefulfor
discussionsandinformationexchangewithmanyfarmersandorganizationsinYoloCounty,
especiallytheYoloCountyPlanningandPublicWorksDepartment,AscentEnvironmental,and
AECOM.Fortechnicalinputongreenhousegasinventorymethods,wewishtothankWebster
TasatandShelbyLivingstonattheCaliforniaAirResourcesBoard,andStephanedelaRuedu
CanattheLawrenceBerkeleyNationalLaboratory.WewouldalsoliketothankDr.
ChangshengLiforDeNitrificationDeCompositionmodelcalibrationandtestingforCalifornia
riceagroecosystems.FundingfortheDeNitrificationDeCompositionmodelingofemissions
fromricewasprovidedbyConservationInnovationGrantprogramadministeredbythe
NationalResourceConservationService;AgreementNumberNRCS693A75787.Planningof
theentireprojectbenefittedfromdiscussionswithDavidShebazianandthestaffofthe
SacramentoAreaCouncilofGovernments(SACOG).ManyUniversityofCaliforniafacultyand
extensionspecialistshavegiveninputontheproject.Wealsoappreciatediscussionswith
DuaneChamberlin(YoloCountyBoardofSupervisors),EdThompson(AmericanFarmland
Trust),SteveShafer(SustainableConservation),andtheinputofmanyotherpeopleonthese
topicsduringthepasttwoyears.WewouldalsoliketothankSusanEllsworthandSarahLinfor
carefuleditingofthisreport.WealsoacknowledgeUnaiPascualfromtheUniversityof
CambridgeandtheBasqueCenterforClimateChange,andRenataBrillingerandJeanneMerrill
fromtheCaliforniaClimateandAgricultureNetwork,forservingasexternalpeerreviewersfor
thispublication.
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ABSTRACT
ThisplacebasedcasestudyinanagriculturalcountyinCalifornia’sCentralValleyfocusedon
theperiodof2010–2050,anddealtwithbiophysicalandsocioeconomicissuesrelatedtoboth
mitigationofgreenhousegas(GHG)emissionsandtoadaptationtoanuncertainclimate.Inthe
past100years,changesincropacreagehasbeenmorerelatedtocroppriceandavailabilityof
irrigationwaterthantogrowingdegreedaysduringsummer,andinfact,summer
temperatureshaveincreasedlessthanwintertemperatures.Econometricanalysisindicatedthat
warmerwinters,asprojectedbyGeophysicalFluidDynamicsLaboratoryBiasCorrected
ConstructedAnalogduring2035–2050,couldresultinlesswheatacreage,morealfalfaand
tomatoacreage,andslighteffectsontreeandvinecrops.TheWaterEvaluationandPlanning
(WEAP)modelshowedthattheseeconometricprojectionsdidnotreduceirrigationdemand
undereithertheB1orA2scenarios,butadiverse,waterefficientcroppingpatterncombined
withimprovedirrigationtechnologyreduceddemandto12percentbelowthehistoricmean.
CollaborationduringdevelopmentofYoloCounty’sClimateActionPlanshowedthatnitrous
oxide(mainlyfromnitrogenfertilizers)wasthemainsource(40percent)ofagricultural
emissions.Emissionsfromcroplandandrangelandwereseveralordersofmagnitudelower
thanurbanizedlandperunitarea.Asurveydistributedto570farmersandranchersachieveda
34percentresponserate.Farmersconcernedaboutclimatechangeweremorelikelyto
implementwaterconservationpractices,andadoptvoluntaryGHGmitigationpractices.Useof
theurbangrowthmodel(UPlan)showedthatchannelingmuchorallfutureurban
developmentintoexistingurbanareaswillincreaseecosystemservicesbypreserving
agriculturallandandopenspace,immenselyreducingtheYoloCounty’sGHGemissions,and
greatlyenhancingagriculturalsustainability.
Keywords:cropacreageshift,farmersurvey,urbangrowthmodel(UPlan),WaterEvaluation
andPlanning(WEAP),waterconservation
Pleaseusethefollowingcitationforthispaper:
Jackson,Louise,VanR.Haden,AllanD.Hollander,HyunokLee,MarkLubell,VishalK.Mehta,
TobyO’Geen,MeredithNiles,JoshPerlman,DavidPurkey,WilliamSalas,DanSumner,
MihaelaTomuta,MichaelDempsey,andStephenM.Wheeler.2012.Adaptation
StrategiesforAgriculturalSustainabilityinYoloCounty,California.CaliforniaEnergy
Commission.Publicationnumber:CEC5002012032.
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TABLE OF CONTENTS
Acknowledgements...................................................................................................................................i
ABSTRACT................................................................................................................................................ii
TABLEOFCONTENTS...........................................................................................................................iii
LISTOFFIGURES.....................................................................................................................................vi
LISTOFTABLES.......................................................................................................................................xi
ExecutiveSummary...................................................................................................................................1
Section1:Introduction..............................................................................................................................5
1.1YoloCounty:BackgroundonAgricultureasRelevanttoClimateChange............................7
1.2PreviousWorkonClimateChangeImpactsonYoloCountyAgriculture..............................8
1.3ClimateChangeScenariosforAgricultureinYoloCounty.....................................................12
1.4References.......................................................................................................................................13
1.5Glossary...........................................................................................................................................16
Section2:ClimateInducedChangesinAcreageofCrops,IncludingProjectionsto2050............18
2.1Introduction....................................................................................................................................18
2.2ProfileofYoloAgriculture............................................................................................................18
HistoricalPerspective......................................................................................................................20
2.3ClimateinYoloCounty.................................................................................................................22
GrowingDegreeDays.....................................................................................................................25
CornHeatUnits...............................................................................................................................28
WinterChillHours..........................................................................................................................29
2.4.EmpiricalEstimationofCropAcreageDecisions....................................................................31
ModelSpecification.........................................................................................................................32
EstimationResults............................................................................................................................35
2.5.ProjectionofClimateinducedChangesinCropAcreages,2010–2050................................40
ProjectionofClimateVariables......................................................................................................41
AcreageProjections:FieldCrops...................................................................................................44
AcreageProjections:VegetableCrops..........................................................................................48
AcreageProjections:TreeandVineCrops...................................................................................50
CropAcreageSharesin2008and2050.........................................................................................54
2.6.Conclusions....................................................................................................................................56
2.7References.......................................................................................................................................
59
iv
Section3:SimulatingtheEffectsofClimateChangeandAdaptiveWaterManagementonthe
CacheCreekWatershed:AlternativeAgriculturalScenariosforaLocalIrrigationDistrict........63
3.1Introduction....................................................................................................................................63
3.2StudyArea......................................................................................................................................65
3.3Methods...........................................................................................................................................66
HydrologyRoutinesinWEAP.......................................................................................................66
ModelBuildandVerificationovertheHistoricalPeriod...........................................................67
Hydrology.........................................................................................................................................68
InfrastructureandOperations:ReservoirsandConveyances...................................................68
HistoricalCropAcreageandIrrigationWaterDemand............................................................69
AdaptationScenariosBasedonClimate,LandUse,andIrrigationTechnologyProjections71
3.4ResultsandDiscussion..................................................................................................................76
ModelPerformanceovertheHistoricalPeriod...........................................................................76
ClimateandAdaptationScenarios................................................................................................77
3.5Conclusions.....................................................................................................................................84
3.6References.......................................................................................................................................85
3.7Glossary...........................................................................................................................................90
Section4:InvolvingLocalAgricultureinCalifornia’sClimateChangePolicy:AnInventoryof
AgriculturalGreenhouseGasEmissionsinYoloCounty..................................................................91
4.1Introduction....................................................................................................................................91
4.2MaterialsandMethods..................................................................................................................92
InventoryMethodsandDataSources...........................................................................................92
DirectandIndirectNitrousOxide(N2O)Emissions...................................................................93
MobileFarmEquipmentandIrrigationPumping......................................................................93
CH4EmissionsfromLivestockandRiceCultivation..................................................................95
ResidueBurning,Liming,andUreaApplication........................................................................96
4.3Results..............................................................................................................................................97
InventoryofAgriculturalEmissionsin1990and2008...............................................................97
4.4Discussion.....................................................................................................................................102
LandUseChangeandItsEffectsonEmissions.........................................................................102
4.5Conclusions...................................................................................................................................108
4.6References.....................................................................................................................................112
4.7Glossary.........................................................................................................................................117
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Section5:FarmerPerceptionsofClimateChangeinYoloCounty:WhatDrivesTheirInclination
toAdoptVariousAdaptationandMitigationPractices?.................................................................118
5.1Introduction..................................................................................................................................118
5.2Methods.........................................................................................................................................119
StudyArea......................................................................................................................................119
SemistructuredInterviewsandMailSurvey............................................................................119
5.3ResultsandDiscussion................................................................................................................120
Farmer’sPerceptionsofClimateChangeandItsImpactsonGlobalandLocalAgriculture
..........................................................................................................................................................120
WhatClimateRelatedImpactsConcernFarmerstheMost?...................................................124
DoesConcernforSpecificClimateImpactsInfluenceWhatAdaptationPracticesFarmers
WillAdopt?.....................................................................................................................................125
WhatInfluencesFarmers’LikelihoodtoAdoptVoluntaryStrategiestoMitigateGHG
Emissions?.......................................................................................................................................130
InfluenceofFarmerContactwithLocalAgriculturalOrganizations.....................................130
LinksBetweenGovernmentProgramParticipationandtheAdoptionofMitigation
Practices...........................................................................................................................................133
HowFarmersViewEnvironmentalRegulationsandtheirInfluenceonMitigation...........133
5.4Conclusions...................................................................................................................................135
5.5References.....................................................................................................................................137
Section6:LandUseChange,GHGMitigation,AlternativeUrbanGrowthPotentialinYolo
County.....................................................................................................................................................140
6.1.Introduction.................................................................................................................................140
6.2.BackgroundonLandUseinYoloCounty...............................................................................141
6.3Methods.........................................................................................................................................143
ModificationstoUPlan..................................................................................................................144
AdditionalUrbanAttractorVariables........................................................................................145
A2‐RegionalEnterpriseStoryline..............................................................................................
146
B1‐GlobalSustainabilityStoryline.............................................................................................147
AB32+PrecautionaryChangeStoryline......................................................................................147
GreenhouseGasEmissionsfromNewUrbanization...............................................................148
6.4.ResultsofUPlanModeling........................................................................................................150
DistributionandAmountofNewUrbanDevelopment..........................................................150
UrbanizationEffectsonAgriculturalCropland........................................................................153
vi
ImpactonUseofSoils,LandForms,andFarmlandProtection..............................................153
ImpactofUrbanizationonTransportationRelatedGHGEmissions....................................156
ResidentialGHGEmissionsfromElectricityandGas..............................................................157
6.5.MitigationandAdaptationImplications.................................................................................157
VisionforaNewRuralurbanFramework................................................................................157
LandUseUnderDifferentClimateChangeScenarios.............................................................160
PotentialImpactofUrbanizationonMicroenvironmentalConditions.................................161
OpportunitiesandChallengesofUrbanizationinResponsetoClimateChange................161
6.6References.....................................................................................................................................163
6.7Glossary.........................................................................................................................................167
Section7:IntegrationandConclusions...............................................................................................168
Appendix1..............................................................................................................................................170
MissingObservationsforWeatherData(Section2).....................................................................170
Appendix2..............................................................................................................................................172
StationarityofTimeSeriesforEconometricAnalysis(Section2)...............................................172
Appendix3..............................................................................................................................................175
CalculationsforTier1InventoryMethodsforAgriculturalGreenhouseGasEmissionsinYolo
County(Section4)..............................................................................................................................175
Appendix3References......................................................................................................................188
LIST OF FIGURES
Figure1.1.MapofYoloCounty,California,ShowingLandUseTypes.TheSacramentoRiveris
theeasternboundaryofthecounty.TheCoastRangeMountainsextendnorthsouthalongthe
westernedge...............................................................................................................................................9
Figure2.1.CaliforniaFarmRevenue($million)andYoloCountyFarmRevenuein2009by
CommodityCategory..............................................................................................................................20
Figure2.2.HistoricalCropAcreagebyCropCategoryforSelectedYearsduring1950–2008.....20
Figure2.3.CropAcreagebyMajorFieldCropforSelectedYears,1950–2008.Cornacreageinthe
early1950swasnotavailable.................................................................................................................21
Figure2.4.AcreagebyMajorOrchardandVineCropforSelectedYearsDuring1950–2008.
Grapeacreagewasnotavailablein1970……………………………………………………………...22
Figure2.5.HistoricalCropAcreagebyMajorVegetableCrops,1950–2008...................................22
vii
Figure2.6.AnnualAverageTemperature,ComputedUsingDailyMinimumandMaximum
TemperatureforthePeriodof1910–2009.............................................................................................23
Figure2.7a.HistoricalAverageMonthlyTemperature(°F)forJulyandAugust,Computed
UsingDailyMinimumandMaximumTemperaturesforthePeriodof1908–2008.......................24
Figure2.7b.HistoricalAverageMonthlyTemperature(°F)forJanuaryandFebruary,Computed
UsingDailyMinimumandMaximumTemperaturesforthePeriodof1909–2008.......................24
Figure2.8.MinimumAverageTemperatureinSummer(JulyandAugust)andWinter(January
andFebruary)Months,ComputedUsingDailyMinimumTemperatureforthePeriodof1909–
2008............................................................................................................................................................26
Figure2.9.MaximumAverageTemperatureinSummer(JulyandAugust)andWinter(January
andFebruary)Months,ComputedUsingDailyMaximumTemperatureforthePeriodof1909–
2008............................................................................................................................................................26
Figure2.10a.GrowingDegreeDaysforSummerCropsfor1909–2009,withGrowthSeason
IncludingAprilthroughAugust............................................................................................................27
Figure2.10b.GrowingDegreeDaysforWinterCropsfor1912–2009,withGrowthSeason
IncludingNovemberthroughMayintheFollowingYear................................................................27
Figure2.11.CornHeatUnitsfor1909–2009foraSeasonBeginningonApril1andEndingon
August31,ComputedUsingDailyMinimumandMaximumTemperature.................................28
Figure2.12.CalculationofDailyChillHoursfromDailyMinimumandMaximum
Temperatures.Theexampleillustratesthecasewhenthedailyminimumtemperatureis30°F(
1°C),andthedailymaximumtemperatureis70°F(21°C).................................................................30
Figure2.13.AnnualChillHoursAccumulatedoverNovemberthroughFebruaryforthePeriod
of1912–2009ComputedUsingDailyMinimumandMaximumTemperature..............................30
Figure2.14a.AnnualAccumulatedGrowingDegreeDaysforSummerMonths,Aprilthrough
August,for2010–2050underB1andA2ScenariosUsingGFDLClimateData.............................41
Figure2.14b.AnnualAccumulatedGrowingDegreeDaysforWinterMonths,November
throughMayfor2010–2050underB1andA2ScenariosUsingGFDLClimateData....................42
Figure2.14c.AnnualAccumulatedChillHours(forNovemberthroughFebruary)for2010–2050
underB1andA2ScenariosUsingGFDLClimateData.....................................................................42
Figure2.14d.AnnualPrecipitation(HundredthInches)forthePeriodfromNovemberthrough
Aprilfor2010–2050underB1andA2ScenariosUsingGFDLClimateData..................................42
Figure2.15a.TenYearMovingAverageofGrowingDegreeDays(GDD)inSummerMonths
(AprilthroughAugust)for2010–2050underB1andA2ScenariosUsingGFDLClimateData..43
Figure2.15b.TenYearMovingAverageofGrowingDegreeDays(GDD)inWinterMonths
(NovemberthroughMay)for2010–2050underB1andA2ScenariosUsingGFDLClimateData
....................................................................................................................................................................43
Figure2.15c.TenYearMovingAverageofChillHoursfor2010–2050underB1andA2
ScenariosUsingGFDLClimateData....................................................................................................43
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Figure2.16a.RiceAcreageinYoloCounty,inthePastandasProjectedwithanEconometric
ModelBasedonHistoricalData.Thelefthalfofthegraphpresentsactualandprojectedacreage
valuesinsolidanddottedlines,respectively,andtherighthalfpresentsprojectedacreagefor
theB1andA2scenariosfor2010–2050usingGFDLclimatedata.Cropacreagesfor2008arethe
startingpointforthefuturemodeling,andallotherfactorsexceptclimateareheldconstant
until2050...................................................................................................................................................44
Figure2.16b.WheatAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................45
Figure2.16c.AlfalfaAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................45
Figure2.16d.SafflowerAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................46
Figure2.16e.CornAcreageinYoloCounty,inthePastandasProjectedBasedontheEstimates
ofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraphpresentsactual
andprojectedacreagevaluesinsolidanddottedlines,respectively,andtherighthalfpresents
projectedacreagefortheB1andA2scenariosfor2010–2050usingGFDLclimatedata.Crop
acreagesfor2008arethestartingpointforthefuturemodeling,andallotherfactorsexcept
climateareheldconstantuntil2050......................................................................................................46
Figure2.16f.IrrigatedPastureAcreageinYoloCounty,inthePastandasProjectedBasedon
theEstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................47
Figure2.17.FieldCropAcreageProjectionsbyCropandbyClimateScenarioforSelectedYears
over2010–2050,asProjectedBasedontheEstimatesofanEconometricModelUsingDatafor
1950–2008.Cropacreagesfor2008werethestartingpointforthefuturemodeling,andallother
factorsexceptclimatewereheldconstantuntil2050..........................................................................48
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Figure2.18a.TomatoAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................49
Figure2.18b.OtherVegetableAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................49
Figure2.19.VegetableAcreageProjectionsbyCropandbyClimateScenarioforSelectedYears
over20102050,asProjectedBasedontheEstimatesofanEconometricModelUsingDatafor
1950–2008.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................50
Figure2.20a.PruneAcreageinYoloCounty,inthePastandasProjectedBasedontheEstimates
ofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraphpresentsactual
andprojectedacreagevaluesinsolidanddottedlines,respectively,andtherighthalfpresents
projectedacreagefortheB1andA2scenariosfor2010–2050usingGFDLclimatedata.Crop
acreagesfor2008arethestartingpointforthefuturemodeling,andallotherfactorsexcept
climateareheldconstantuntil2050......................................................................................................51
Figure2.20b.GrapeAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................51
Figure2.20c.AlmondAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................52
Figure2.20d.WalnutAcreageinYoloCounty,inthePastandasProjectedBasedonthe
EstimatesofanEconometricModelUsingDatafor1950–2008.Thelefthalfofthegraph
presentsactualandprojectedacreagevaluesinsolidanddottedlines,respectively,andthe
righthalfpresentsprojectedacreagefortheB1andA2scenariosfor2010–2050usingGFDL
climatedata.Cropacreagesfor2008arethestartingpointforthefuturemodeling,andallother
factorsexceptclimateareheldconstantuntil2050.............................................................................52
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Figure2.20e.MiscellaneousFruitAcreageinYoloCounty,inthePastandasProjectedBasedon
theEstimatesofanEconometricModelUsingD