THEBANANACARBONFOOTPRINTCASESTUDYBYANTHONYJ.CRAIGANDDR.EDGARE.BLANCOMITCENTERFORTRANSPORTATION&LOGISTICSSEPTEMBER,2009

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THEBANANACARBONFOOTPRINTCASESTUDYBYANTHONYJ.CRAIGANDDR.EDGARE.BLANCOMITCENTERFORTRANSPORTATION&LOGISTICS,CAMBRIDGEMA,USASUMMARY:Thisdocumentdescribesindetailtheprocessofestimatingthecarbonfootprintofabanana.Thecasestudyestimatedatotalfootprintof121gofCO2­equivalents,withtransportationandfarmingbeingthelargestshareofemissions(36%and29%respectively).Adescriptionofthebreadth,depthandprecisionoftheestimationisincludedinthedocument,aswellasanillustrativeassessmentonthelevelofuncertaintyofthecarbonfootprintcalculation.

Introduction

ThiscasestudyinvolvesthecooperationofChiquitaBrandsInternational(CBI),aleadinginternationaldistributoroffruits,andShaw’s,aNewEnglandbasedgrocerystorechain,tomeasurethecarbonfootprintofbananas.Theinitialphaseofthisresearchhasinvolvedinterviewswithkeypersonnel,mappingofthesupplychain,visitstoadistributioncenterandretailstore,andcollectionofrelevantdata.Workingwiththepartnercompaniestheactivitiesassociatedwiththesupplychainwereexaminedforanygreenhousegasemissionsthatmightbeproduced(measuredinCO2equivalentsorCO2e).Foreachemissionsgeneratingactivitydatawascollectedregardingtheamountofemissionsgeneratedandthequantityofbananasinvolvedintheactivity.Inthismannertheemissionscanbeallocatedtotheproductinordertodeterminethecarbonfootprintofapoundofbananassoldataretailoutlet.Fordatathatisnotavailablefromthepartnercompaniesestimateshavebeenmadefromsecondarydatasources.Thecurrentworkhasfocusedonmaterialsthatareconsumedandusedduringthehandlingprocess,andcapitalgoodshavebeenexcluded.

TheBananaSupplyChain

BananassoldintheUnitedStatesaretypicallygrowninCentralAmerica.CBIworkswithanetworkofownedplantations,independentgrowers,andwholesalersatmorethan200locations,primarilyinGuatemala,Nicaragua,andCostaRica.Thoughpracticesmayvaryfromfarmtofarmbananacultivationofteninvolvestheapplicationoffertilizers,pesticides,andfungicides.Oncethebananasapproachripenesstheyarepickedattheplantationandpackagedfortransportation.Thebananasareshippedfromthepackinglocationsbytruckinrefrigeratedcontainerstooneofthreeoutboundports.OncetheyarriveatportthebananasremainintherefrigeratedcontainersandareloadedonoceanvesselsforshipmenttooneoffiveportsintheUS.AfterarrivingintheUSthecontainersareunloadedfromtheshipandthebananasaremovedfromthecontainerstorefrigeratedwarehouseslocatedneartheport.FromthewarehousebananasareshippedeithertoCBIdistributioncentersortakentocustomersDCs.ThistransportationcanbearrangedbyCBIorbythecustomer.UponreachingtheDCthebananasundergoachemicalripeningprocessusingethylenegasthatlasts3‐4days.Attheendofthisprocessthebananasare

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readyforsaleandareimmediatelyshippedtoretailoutlets.Attheretailoutletbananasrequirenospecialhandlingorcaresuchasrefrigeration.Bananasareafastmovingproduct,withmostbananastypicallybeingsoldwithinadayofarrivingatthestore.Inadditiontothebananasthemselvesanumberofadditionalmaterialsareusedtopackagethebananasfortransportandsale.FromthepackingstationtotheDCbananasarenormallyshippedincontainerquantities.Eachcontainerholds20palletsof48bananaboxes,foratotalof960boxespercontainer.Eachboxcontainsapproximately40pounds(18kgs)ofbananaswrappedinaplasticlinerandplacedinacardboardbananabox.ThebananaboxesandlinersareprocuredbyCBIandsentfromtheUStoCentralAmericaduringthebackhaulportionoftheoceanvoyage.Thematerialsaresenttothepackingstationsinthetrucksthatwillbeusedtotransportthebananasfromthepackingstationtotheport.Additionalpackingmaterialsincludereusablewoodenpallets,cardboardpiecesusedtohelpsecureboxesofbananasonpallets,andplasticshrinkwrapusedwhentransportingpalletsofbananasfromtheDCtothestore.ThoughChiquitasuppliesthecardboardandplasticusedinpackingbananasthesematerialsareeventuallydisposedofbyretailerswhopurchasebananasfromCBI.AtShaw’sgrocerystoresthecardboardusedinpackingissavedandsenttoarecycler,whilethe

plasticliningandshrinkwraparethrownoutaswaste.Beyondthebananasandthepackagingmaterialstheonlyotherproductconsumedduringthebananasupplychainistheethylenefluidusedintheripeningprocess.ThisfluidispurchasedfromtheproducerandshippedtotheDCthroughaparceldeliveryservice.Thefluidispackagedinsideaplasticbottle.One32oz.bottleofethylenefluidisusedtoripenonetruckloadofbananas.Afteruseintheripeningprocesstheemptybottlesarediscardedaswaste.AmapofthesupplychainisshowninFigure1.

EmissionsandDataSources

Theemissionsconsideredinthisanalysiscangenerallybeplacedinoneofthreecategories:emissionsfrommobilecombustion,emissionsfromenergyuseandelectricityconsumedinfacilities,andemissionsrelatedtoproductionanddisposalofmaterialsusedthroughoutthesupplychain.Thematerialsincludenotonlypackagingmaterialssuchascardboardandplastic,butalsoemissionsrelatedtothechemicalsusedinthegrowingofbananasandproductionofethylenefluid.Intheoryeachofthesematerialscanthemselvesbetracedbackthroughthesupplychaintoquantifytheiremissions,however,thisrequiresinformationnotavailabletothepartnercompanies.InthiscasetheseemissionscanbequantifiedusingavailableLife‐cycleAssessment(LCA)data.

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Figure1.BananaSupplyChainMap

MobileCombustionTheprimaryemissionscontributionsformobilecombustioncomefromgroundtransportationofthebananasbytruckandoceantransportationofthebananasfromCentralAmericatotheU.S.SecondarycontributionsincludeoceantransportationofcardboardboxesfromtheU.S.toCentralAmerica,groundtransportationofethylenefluidandpackingmaterialstotheDC,andtransportationofchemicalstothebananafarms.

GroundTransportation

GroundtransportationofthebananasincludesshippingfromthegrowertotheoutboundCentralAmericanport;inboundfromtheU.S.porttotheDC;andoutboundfromtheDCtotheretailstore.Shippingdistancefromthegrowertoportcanvarybasedonwherethegrowerislocatedandwhichshippingportwasused,thereforeanaveragedistancetoportwasusedbasedonlogisticsdataprovidebyCBI’soperationsin

thetropics.Thisdataincludedthetotalkilometerstraveled,thenumberofequivalentcontainersmoved,anddataregardingfuelconsumptionfromthegensetunitsthatprovidedrefrigerationintransit.Shippingdistancesatthedestinationsidesimilarlycanvarydependingontheexactpathtraveledbythebanana.Forthisstudyan“average”NewEnglandbananawasused.ThisaveragebananawasassumedtotravelbyoceantotheportofWilmington,DE.FromthereittraveledbytrucktoaBostonareaDCandfinallytoaretailstore.ThedistancefromtheDCtothestorewasbasedoninformationprovidedbyShaw’sfromtheirtransportationmanagementsystem.TotalroundtripkilometersforallshipmentsfromtheDCtostoreswasreported,lessanybackhaultrips,alongwiththetotalcasesofbananasshippedtodetermineanaveragedistancefromDCtoretailstore.Additionalinformationregardingfuelconsumptionofthereeferunitusedtoproviderefrigerationwasalsoprovided.Thiswasbasedonanaverageconsumptionofone

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gallonofdieselperhourofuse.Averagespeedwasestimatedat36mph,andcombinedwiththedistanceoftheshipmentthisprovidedanestimateofthetotalfuelconsumptionrequiredbythereefer.AdditionalgroundtransportationemissionswerecalculatedforshipmentoftheethylenefluidfromthedistributortotheDCandforchemicalsfromadistributortothebananafarm.FortheethylenefluidatraveldistancewasestimatedusingGooglemapsfunctionalitytocalculatethedrivingdistancefromthedistributor’scitytotheDC.Chemicalshipmentstothebananafarmswillvarydependingonthelocationofthefarmandthesourceofthechemicals.Thisdistancewasassumedtobe100kmforthepurposeofthisstudy.GreenhousegasemissionswerecalculatedforthegroundtransportationusingSimaProLCAsoftware.Foreachshipmenttheweightanddistancewereusedtocalculatethetotaltonne‐kilometers(tkm)oftheshipment.SimaProoffersavarietyofdifferentroadtransportationoptions,butforconsistencya32tonnelorrywasassumedtohandleallgroundtransportation.SimaProisaLife‐cycleAssessmenttool,andassuchthegreenhousegasemissionsarebasedonthefulllife‐cyclerequiredforroadtransportation.Thisincludesconstructionofthelorry,maintenanceofthevehicle,roadconstruction,aswellasthefulllife‐cycleemissionsforthedieselfuelconsumedbythevehicle.Forthe32tonnelorrytheestimatedemissionsare165gramsofCO2epertkm.Themajorityoftheseemissions,approximately86%,comefromtheproductionandconsumptionofthedieselfuel.Intotalthegroundtransportationaccountsforapproximately36gramsofCO2eperbanana.ThebreakdownofgroundtransportationemissionsbysourceisshowninFigure2.

Figure2.GroundTransportation

EmissionsbySource

OceanTransportation

EmissionsfromoceantransportationwerecalculatedbasedontheshippingdistancefromPuertoMoin,CostaRicatoWilmington,DE.WilmingtonwaschosenasthedestinationportbecauseitistheportusedtoservetheNewEnglandmarketforshipmentsmadebyCBI.PuertoMoinwaschosenastheoriginportbecausemorethan80%ofbananasshippedbyCBItoWilmingtonusePuertoMoinastheoriginport.AsmallernumberofbananasareshippedfromAlmirante,PuertoBarrios,andPuertoCortes.Theshippingdistancewasdeterminedbasedoninformationprovidedbydataloy.com,aservicethatprovidesshippingdistancesbasedonthemostheavilytraveledshippinglanes.ThetotaldistancewascalculatedbasedonatriporiginatinginPuertoMoin,makingintermediatestopsatPuertoBarriosandPuertoCortes,andeventuallyarrivingatWilmington.AnestimationoftheemissionsrelatedtoshippingthecardboardpackingboxesbyoceanfromtheUStoCentralAmericawasalsoperformed.BasedoninformationfromCBItheboxesaretypicallyshippedoutofNewOrleanstothetropicsonthebackhaulportionofthebananaoceanshipments.Againusinginformationfromdataloy.comthedistancewascalculatedforashipmentoriginatinginGulfport,LAandarrivinginPuertoMoinwithintermediatestopsatPuertoCortesandPuertoBarrios.

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GreenhousegasemissionsforoceantransportationwerecalculatedinSimaProusingasimilarmethodtogroundtransportation.Foreachshipmenttheweightanddistancewereusedtocalculatethetotaltonne‐kilometers(tkm)oftheshipment.Thetransoceanicfreightshipmenttransportprocesswaschosentomodeltheoceanshipments.InadditiontoemissionsfromtheoperationofthevesselSimaProincludesemissionsfromtheconstructionofthevessel,maintenanceofthevessel,operationoftheport,constructionoftheport,andmaintenanceattheport.SimaProestimatesthecontributionfromtransoceanicfreighttobe10.6gramsofCO2epertkm.Almost86%oftheemissionsaretheresultofproductionandconsumptionofheavyfueloil,while13%comesfromoperationsattheport.Overall,oceantransportationaccountsforonly8gramsofCO2eperbanana.Nearly7ofthosegramscomefromtheactualtransportation,andjustover1gramiscontributedbyportoperations.

DirectEnergyConsumptionNon‐transportationenergyconsumptioncanbebrokendowntothreesources:distributionfacilitiessuchastheDCandretailstore,electricityusagebyreefercontainerswaitingattheport,andenergyuseatthefarm.

DistributionFacilities

Electricityistheprimaryenergyconsumedatfacilitiesusedinthedistributionofbananastotheconsumer.ThisincludesaDistributionCenterwherebananasundergotheripeningprocessandaretailoutletwheretheyaresoldtotheendconsumer.OperationsattheDCrequiringenergyincludeheating,cooling,andlightingofthefacility;electricitytopowercargohandlingequipment;andelectricitytopowerthebananaripeningrooms.Bananastypicallyrequirenospecialhandlingattheretailoutlet,butelectricityisconsumedatthestoreforheating,lighting,officeequipment,checkoutregisters,andotheractivitiesrequiredtorunthestore.Inadditiontoelectricityasmalleramountof

energyisusedintheformofnaturalgastoprovideheat.Energyconsumptionatfacilitieswascalculatedbasedonactualutilitybills.ThesewereprovidedbyShaw’sfortheirDCthathandlesbananasandaretailoutletselectedtoberepresentativeoftypicaloperations.Oncetotalenergyforthefacilitieswascalculatedtheenergyneededtobeallocatedtobananasinsomemanner.Eachfacilityhandlesmanydifferentproducts,butnoinformationwastrackedthatbreaksdownelectricityusagebyproduct.AttheDCenergywasfirstallocatedtobananasbasedonthepercentageofsquarefootageofthefacilityoccupiedbythebananaroom.Bananasareahighvolumeproduct,andhavetheirownseparatespaceforstorageandripeningwithinthefacility.Whilethismethodiseasilycalculateditlikelyoverestimatestheamountofenergytrulyrequiredforbananas.ThisparticularDChandlesfrozenandrefrigeratedproducts.Bananasarekeptslightlybelowroomtemperature,butthisrequireslessenergythanotherareasoftheDCwhichmustbekeptbelowfreezing.Energyattheretailstorealsorequiredsomemethodofallocatingtheenergyconsumptiontobananas.Forthisphaseanallocationbasedoneconomicfactorswasused.Aretailgroceryoutletsellsthousandsofdifferentproducts,andallocatingbasedonothermeansrequiressignificantamountsofinformationthataretypicallynotavailable.Salesinformationisreadilyavailable,however,andenergywasallocatedbasedonthepercentageoftotalstoresalesrepresentedbybananas.Theenergyconsumptionwasthendeterminedatanindividualbananalevelbydividingtheallocatedenergybythetotalpoundsofbananassoldatthestoreduringthetimeperiod.CarbonemissionsfromtheconsumptionofelectricitywerecalculatedinSimaProbasedontheaveragefuelmixwithintheUnited

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States.Thisestimatestotalemissionfromelectricityconsumptionat741gramsofCO2eperkWh.Ofthe741gramsmorethan90%comesfromemissionsreleasedduringthecombustionoffuelstoprovidetheelectricity.Theremainingemissionscomemainlyfromtheextractionandprocessingofthefuelandthecreationofinfrastructure.EmissionsfromnaturalgasarelikewisebasedontheaverageU.S.case,withanestimatedvalueof65gramsofCO2epercubicfoot.TheenergyuseattheDCandretailstorecombinestoproduceonly14gramsofCO2eperbanana.Nearlyalloftheseemissionscomefromtheelectricity,withthecontributionofnaturalgasconsumptionbeinglessthan1gram.WhiletheDCfacilityasawholeusesmoreenergythantheretailstoreitmakesamuchsmallercontributiontothecarbonfootprintofthebananaduetothehighvolumeofproductshandled.Ofthe14gramsofCO2eaboutonly1gramiscontributedbytheDC,withtheremaining13comingfromtheretailstore.

ElectricityatthePort

BananasareshippedfromfarmsinthetropicstotheUSinrefrigeratedreefercontainers.Duringtransportationthesereefersconsumepowerfromtheshiporageneratingunitonthetruck.Oncetheyarriveattheportthereistypicallyawaituntiltheyarereadytobeloadedontheoceanvessel.Duringthistimethereefersdrawelectricpowerfromthegridtopowertherefrigerationunit.BasedonaninterviewwiththelogisticsmanagerforLatinAmericaitwasdeterminedthatthebananasspendnomorethanthreedayswaitingattheport,withanaverageoftwodays.Thepowerratingfortheunitsis10kW.Givenanapproximate48hourwaittimethereeferswillconsumeapproximately480kWhofelectricity,withafullreeferholding960boxesofbananas.NoelectricityfactorsareavailableinSimaProforthecountriesinthetropicsthatCBIshipsbananasfrom;insteadtheaverageU.S.electricitymixwassubstituted.

Farms

Inadditiontotheenergyconsumptionatthedistributionfacilitiesenergyisalsousedbythefarmswherebananasaregrown.Thoughbananafarmingstillreliesheavilyonmanuallaborenergyisneededtopowerfarmequipment,spraychemicals,andpowerbuildings.Practicesvarybetweenfarms,andatthistimegooddataregardingtheenergyconsumptionatfarmswasnotavailable.InsteadthisinformationwasestimatedusingagenericfruitfarmingprocesswithinSimaPro.Emissionswereestimatedfortheenergyuserequiredtofarmonehectare,anddataprovidedbyCBIregardingaveragefarmyieldswasusedtoallocatethistoindividualbananas.Thisprocessestimatestheemissionsrequiredtoproduceonebananaat12gramsofCO2e,themajorityofwhichcomesfromdieselfuelconsumedinfarmequipment.

MaterialsCarbonemissionsrelatedtotheproductionofmaterialsusedinthesupplychaincanbeplacedintotwocategories:packagingmaterialsandchemicals.Packagingmaterialsincludedintheanalysiswerethecardboardbananabox,theplasticshroudusedtowrapbananasinsidethebananabox,plasticwrapusedduringoutboundtransportationfromtheDC,andcardboardcornerboardusedtohelpstabilizetheboxesofbananasfortransport.Thechemicalsusedinthesupplychainincludethepesticides,fertilizers,andfungicidesusedatthebananafarmsalongwiththeethylenefluidusedtoripenthebananasattheDC.

Packaging

Themostsignificantaspectofthebananapackagingisthecardboardboxinwhichthebananasareshipped.BasedoninformationprovidedbyCBIregardingpackagingspecificationeachboxisestimatedtobeabout2.5poundsofcardboard.TheemissionsrelatedtoproducingtheboxareestimatedusingSimaProforamixedfiber,singlewall,corrugatedcardboard.Theemissionsfactorforproductionofthe

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cardboardisapproximately432gramsofCO2eperpoundofcardboard.InadditiontotheproductionoftheboxemissionsrelatedtoitsdisposalarecalculatedinSimaProaswell.Theemptyboxistypicallycollectedattheretailoutletfordisposal.InthisspecificcasethedisposalwasmodeledasbeingsenttoastandardmunicipalwasteintheU.S.whereit’sfinaldisposalisbasedonamixoflandfillandincineration.Theemissionsrelatedtodisposaloftheboxareapproximately18gramsofCO2e.TheplasticshroudwasbasedonpackagingspecificationprovidedbyCBI.ItwasmodeledinSimaProasplasticpackagingfilmandusedthesamemunicipalwastedisposalscenarioasthecardboardbox.Theoverallcontributionoftheshroud,includingproductionanddisposal,wasabout1gramofCO2eperbanana.Theremainingmaterialsusedduringdistribution,includingtheshrinkwrapandcardboardcornerboard,weremodeledinamannersimilartotheboxandshroud.Duetothelimitedquantitiesusedofthesematerialsthetotalcontributionwaswellbelow1gramofCO2eperbanana.

Chemicals

DataregardingthechemicalsusedtohelpgrowthebananasatthefarmisbasedonrecommendeddosesprovidedbyCBI.Actualusagewillvaryfromfarmtofarmbasedonspecificconditionsandmanagement.Inordertoaccountforthiswheneverarangeofvalueswasprovidedtheupperendwasusedinordertoprovideaconservativeestimateoftheactualemissions.TypicallytheguidelinesfromCBIarebasedonarecommendedamountoftheactiveingredientinthechemical,suchasN,P,orK.SimaProusesasimilarclassification,whereseveraldifferenttypesoffertilizersmaybeavailable,buttheyaremeasuredbythequantityoftheactiveingredient.Withoutknowledgeofwhichspecificchemicalmayhavebeenusedoneofthechoiceswasmadefromthelist.ManyofthechemicalsusedwerenotavailableinSimaProorcouldnotbeidentified.Inthiscaseasimilarquantityofanavailable

chemicalwaschosenfromtheSimaProdatabaseasasubstitute.Futureworkmayinvolverefiningthechoiceofchemicalsorprovidingasensitivityanalysisbasedonthechoiceofdifferentchemicals.Thechemicalusagewasbasedonrecommendeddosesperhectareperyear.Theemissionsfromthesechemicalswerethenallocatedtothebananasbasedontheaverageannualyieldperhectare.BasedonthedatafromSimaProtheaverageemissionsfromtheproductionofthesechemicalswas3100gofCO2eperkgofchemical.Thiscontributedapproximately23gofCO2perbanana.ThelargestsinglecontributorwasNitrogenintheformofAmmoniumNitrate.Includedintheemissionsestimateforthechemicalswastrucktransportationof100kmtoaccountfortransportofthechemicalsfromaregionalvendortothefarm.Inadditiontochemicalsusedtogrowthebananasasmallamountofethylenefluidwasusedtochemicallyripenthebananasjustbeforesale.One32ozbottleofethylenefluidiscapableofripeningafullcontainer(960boxes)ofbananas.ThiswasmodeledinSimaProasproductionof32ozofethylene,productionofaHDPEplasticbottletocontainit,andtrucktransportationfromthevendor’slocationtotheShaw’sDC.InadditiontheplasticbottlewasdisposedofusingthestandardU.S.municipalwastescenario.Duetotherelativelysmallamountsofplasticandethyleneusedtoripenanentirecontainerofbananasthetotalcontributionamountedtolessthan1gramofCO2eperbanana.

Results

Theendresultofthiscasestudywasanestimatedcarbonfootprintofapproximately121gofCO2eperbanana.Thisisbasedonan“average”NewEnglandbanana.OceanandroaddistanceswereallbasedondatarequiredtogetthebananastoShaw’sBostonareaDC,anddistancetostoreswasbasedonShaw’soperationsinNewEngland.Figure3showsabreakdownofthesupplychainalong

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withtherelativecontributionofeachpieceingramsofCO2eperbanana.Figure4provides

arelativebreakdownoftheemissionsbysource.

Figure3.BananaCarbonFootprintbySupplyChainElement

Figure4.BananaCarbonFootprintContributionbySource

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CarbonFootprintUncertainty

Severalfactorsimpactedtheaccuracyofthecarbonfootprintestimation.First,andmostimportant,isthedifficultyingatheringallnecessarydata.Theseproblemscanarisefromseveraldifferentissues.Insomecases,suchaspowerconsumptionofthebananaripeningrooms,itisdatathatisnotspecificallytracked,andthereforedifficulttoseparatefromtheaggregatepowerconsumptionforthewholefacility.Theuseofaggregatedatacreatesfurtherissueswithhowtoallocatetheemissionstodifferentproducts.Iftheemissionscannotbedirectlytrackedattheproductlevelsomemethodmustbeusedtodeterminewhichsharegoestowhichproducts,andinmanycasesitisnotclearthatthereisasinglebestanswerforhowthisshouldbedone.Inothercasesthedataneedstocomefromsourcesoutsideofthepartnercompanies.Oftenthisdatawasnotavailable.Receivingdatafrommultiplesourcesalsocreatesissuesofconsistency.Forexample,whenreportingmilesdrivenorgallonsburnedduringshippingitmustbeclearwhetherthisincludesthereturntriporbackhaulforotherproducts.Whenspecificdatawasnotavailableithadtobeestimatedbasedonsecondarysources.InthecaseofthisstudymuchofthesecondarydatawastakenfromdatabasesavailableintheSimaProLCAtool.Whendataisnotavailable,aswasthecaseforseveralofthechemicalsusedduringthebananafarmingoperations,asubstitutechemicalwasused.Theaccuracyofthesesubstitutionsaddsalayerofuncertaintythatisdifficulttoestimatewithoutadditionalinformation.Finally,thenecessityofproducingasinglenumberrequirestheuseofaveragedataand

certainassumptions.Inmanyinstancestheactualcarbonfootprintofaspecificbananamayvarysignificantlyfromthissinglenumber.Thechemicaluse,farmingtechniques,traveldistances,facilityenergyefficiency,andelectricitygenerationmixcanbedifferentforeachbanana.Withhundredsoffarmsandthousandsofenddestinationsasinglenumbercannotaccuratelyrepresentatruecarbonfootprintofanyspecificproduct.Dependingonthewaythiscarbonfootprintinformationisusedthesedifferencesmayormaynotproverelevant.

QuantifyingUncertaintyThecasestudyuseddetailedinformationoftheretaildistributionnetworktotheNewEnglandArea.Approximately36%ofthebananafootprintisassociatedwiththetransportationnetwork,thelargestshareoftheemissions.However,bananasareshippedallthroughthecontinentalUnitedStatesusingavarietyofdistributionnetworks.Inordertoillustratetheimpactofthedistributionnetworkonthecarbonfootprint,weanalyzedavarietyofdistributionnetworkstodifferentregionsintheUnitedStatesaswellasavarietyofunderlyingtransportationnetwork.Figure5.ShowsselectedcitiesintheUnitedStatesandtheirassociatedcarbonfootprint.Wecanseethatbananacarbonfootprintsvaryfrom97gto168gdependingonthefinalretaildestination,alargerangeheavilydependentontheunderlyingstructureofthesupplychain.Similaranalysisshouldbeperformedtoestimatetheimpactoffarmingpractices,thesecondlargessourceofemissionsinthebananacarbonfootprint.

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Figure5.–CarbonFootprintVariationbyDestination

NEXTSTEPSForfurtherinformation,contactDr.EdgarBlanco,DirectoroftheMITCTLCarbonEfficientSupplyChainsprojectat:eblanco@mit.edu,ortel:+16172533630

Acknowledgements

TheauthorswouldliketoacknowledgethesupportofChiquitaBrandsInternationalindevelopingthisdocument.ThisresearchwaspartiallyfundedbytheMIT‐PortugalProgram.