兰德-管理地球工程地缘政治风险的国际法律机制（英文）-2021.5-26正式版

CLIMATE

CONTROL

InternationalLegalMechanismsforManagingthe

GeopoliticalRisksofGeoengineering

MICHELLEGRISÉ|EMMIYONEKURA|JONATHANS.BLAKE|DAVIDDESMETANUSREEGARG|BENJAMINLEEPRESTON

Perspective

EXPERTINSIGHTSONATIMELYPOLICYISSUE

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InFebruary2009,aprovincialweatherbureauinnortheasternChinafired313sticksofsilveriodideintothecloudsoverBeijing.Intendedtoalleviatethelongestdroughtinalmost40years,theeffortledto

massivesnowfallandtheclosureof12highways.1Overthepastdecades,asweathermodificationtechnologies,suchascloudseeding,havematuredandenlargedintermsoftheirscopetointervenewithglobalclimatechange,theprospectoffutureman-madenaturalhazardshasloomedlarger.Asclimatechangeposesevergreaterthreatstohumanandnaturalsystems,scientistsandpolicymak-ershaveexplorednovelwaystoreducegreenhousegas(GHG)concentrationsintheatmosphereandtomitigatetheireffectsontheclimate.2Geoengineering—whichwedefineastheintentional,large-scalemanipulationofanenvironmentalprocessonEarthtocounteracttheeffectsofclimatechange—representsawaytodoboth.Butsomeformsofgeoengineeringhavebeenextremelycontroversialinclimatepolicydebates,becausetheyinvolvediversionofresourcesawayfromemissions-reductionefforts,wherethereisclearscientific(ifnotpolitical)consensus.Thishaslimitedtheamountofresearchandpolicymakingongeoengineering.

Astheimpactofclimatechangeonhumanandnaturalsystemshasincreasedinrecentyears,3manygovernments—includingthoseofCanada,France,NewZealand,andJapan—haverecentlydeclaredclimateemergenciesandbegunconsideringmore-extremerisk-managementstrategies.China’scontinuedinvestmentinweather-modificationtechnologies4andSwitzerland’sleadershiponaUnitedNations(UN)proposalforgeoengineeringgovernancesuggestthatgeoengineeringisbeingconsidered.5Althoughthescientificdevelopmentsrelatedtogeoengineeringhavegarneredattention,thesetechnologiesalsorequirethedevelopmentofeffectiveandcomprehensivegovernancemechanismstoaddressthenewrisksassociatedwiththem.

InthisPerspective,weconsiderthegeopoliticalrisksofgeoengineeringandtheroleofinternationallegalmechanismsinmanagingtheserisks,bringingtobearinsightsfromsubject-matterexpertsonclimatepolicy,internationalrelations,andinternationallawprovidedaspartofaworkshop,aaswellastherelevanttechnical,internationalrelations,andinternationallawliterature.

Workshopparticipantsincluded24academicresearchexpertsonsolarradiationmanagement,carbondioxideremoval(CDR),climate

1

WhatIsGeoengineering?

Thetermgeoengineeringcoversabroadrangeoftechnologiesthatcanbegroupedintotwocategories:CDRandsolarradiationmanagement(SRM).6CDRtechnologiesaimtotakecarbondioxideoutoftheatmosphere,creatingessentially“negativeemissions,”toloweratmosphericgreenhousegasconcentrationsandreducewarming.

SRMtechnologiesaimtoreflectincomingsunlightawayfromtheEarthwithcloudsorotherreflectivesubstances,therebyreducingthewarmingoftheatmosphere.

Bothtypesofgeoengineeringareperceivedbymanyclimatescientistsasapotentialdiversionofresourcesfromemissions-reductionefforts.7Thereareimportantdifferencesbetweenthetwocategories,however,bothintheirlikelyeffectsandhowtheyareviewedbyresearchersandpolicymakers.Crucially,mostlow-carbonclimatescenariosassumesignificantuseofCDRasamitigationmeasure.TheIntergovernmentalPanelonClimateChange(IPCC)hasalreadystatedthatitconsidersCDRtobeanecessaryelementinreducingemissions.TheanticipatedroleofCDRinmitigatingtheeffectsofclimatechangehasimportantimplicationsforitsregulation.

Therearemanygeoengineeringtechnologiescurrentlyunderinvestigationanddevelopment.Tables1and2listsomeofthemorecommonlyinvestigatedCDRandSRMtechnologies,respectively,althoughthislistisnotmeanttobeexhaustive.

policy,internationalrelations,andinternationallaw.Theworkshopwasconductedovertwodaysandincludedfocuseddiscussionsaboutfutureclimatepathways,theirassociatedgeopoliticalrisks,andtheroleofinternationallegalmechanismsintheresolutionofthosegeopoliticalconsequences.

Abbreviations

CBD ConventiononBiologicalDiversity

CCAMLR ConservationofAntarcticMarine

LivingResources

CDR carbondioxideremoval

CO2 carbondioxide

ENMOD EnvironmentalModificationTreaty

GHG greenhousegas

GtC gigatonofcarbon

IPCC IntergovernmentalPanelonClimate

Change

LC/LP LondonConventionandLondonProtocol

NOx nitrogenoxide

SRM solarradiationmanagement

UN UnitedNations

UNFCCC UnitedNationsFrameworkConvention

onClimateChange

W/m2 wattpersquaremeter

Thetablesdetailthefollowingtechnicalcharacteristicsofeachtechnology:

Technicalreadiness:Measuresthematurityofaspecifictechnology.Forexample,“high”indicatesatechnologythathasbeenprovensuccessfulinitsmissionoperation,and“medium”indicatesacomponentthathasbeenvalidatedinarelevantenvironment.

Costmagnitude:Becauserigorouscostestimatesofgeoengineeringtechnologiesaregenerallyunavailable,ourratingsindicatethecostorderofmagnitudewithassumptionsnotedfortheamount

2

Table1.SelectCarbonDioxideRemovalTechnologies

Technical

CostMagnitude

GeoengineeringTechnology

Readiness

(inU.S.dollars)

TimeScale

SecondaryEffects

Large-scalereforestationorafforestation

High

$100billion(for1

Decades

Increasedfertilizationandirrigationriskwater

focusesonconservingforestsandjungles,

gigatonofcarbon

pollution,nutrientrunoff,anddepletionof

aswellaslarge-scaleplantingofnon-

[GtCa])

freshwater;microclimatealterations;unequal

forestedareas

land-useburdenonwell-forestedareas,likely

developingcountries

Bioenergywithcarboncaptureandstorage

Medium

Trillions

Aboutadecade

EmitCO2viabioenergyprocessesandCO2

capturesCO2releasedfrombioenergy

(for100GtC)

capture;land-rightsconflictfromhigher

applications(e.g.,biofuels,biomassburning)

demandforagriculturallandandfertilization;

andstoresitingeologicalformations

microseismicity;disposalofcapturedCO2isa

underground

concern8

DirectaircapturepullsCO2outoftheair

Medium

Trillions

Aboutadecade

Scalingupprocessrequireslargeamountsof

viachemicalorelectrochemicalmeans

(for100GtC)

energyandwater;threatoftoxicityofchemicals;

disposalofcapturedCO2isaconcern

Oceanironfertilizationaddsironinto

Low/medium

10billion

1–5years

Surfacecoolingand/orseasurfacetemperature

theoceantoincreasephytoplankton,

(for100GtC)

increase;ozonedepletion;potentiallyproduce

whichstoreCO2fromtheatmosphere

otherGHGs,suchasnitrogenoxides(NOx);

ecosystemdisruptionwithoceanacidification,

algalblooms,andoceanoxygendepletion,

causinglossofoceanlife.9

SOURCE:RANDanalysiswithcostordersofmagnitudebasedonreviewpublications.10

Theforestationcostmagnitudeisshownonlyfor1GtCbecausethereislesscapacityforthistechnologytoscaleupbecauseoflimitationsonhowmuchlandcanbemadeintoforest.

ofCO2removedforCDRandthesolarradiationinW/m2reflectedforSRM.Theseestimatesarebasedonassessmentsintheexistingliterature,includingpressreleases,butgiventhatmanyofthesetechnologieshaveyettobeimplementedortestedatscale,significantuncertaintyremains.

Timescale:Thisestimate,basedonexistingscientificstudiestotheextentpossible,indicatesthetimefromimplementationtoreachinganapplicableclimategoal.Itreferstotechnicalefficacywithoutadditionaltimetoaccountforpoliticalfeasibility.

Secondaryeffects:Thesearethepotentialclimate,weather,andlanduseimpactsofeachtechnology,basedonexistingscientificstudiestotheextentpossible.

CDRtechnologiesrepresentarangeofopportunitiesandcosts.Forexample,forestationisreadilydeployablebasedonsmall-scaledemonstrations.Incontrast,scientistsarestilldevelopingandtestingincontrolledresearchsettingsvariousapproachestopullCO2outoftheatmosphereandstoreit—technologyusedbybothbioenergy(withcarboncaptureandstorage)anddirectaircapture.Significantinvestmentwouldstillbeneeded

3

Table2.SolarRadiationManagementTechnologies

CostMagnitude(inU.S.

Technical

dollars)forWattper

GeoengineeringTechnology

Readiness

SquareMeter(W/m2)

TimeScale

SecondaryEffects

Stratosphericaerosolinjection

Low/medium

Billions

Years

Generally:higherlatitudewarming,changesin

involvessprayinginorganicparticles

(for2–5W/m2)

precipitation,ozonedepletion,uncertainpublic

(e.g.,sulfurdioxide)intothe

healthimpactsfromfood/watercontaminants,

stratospheretoreflectsunlight

oceanacidification,highriskifSAIstopssuddenly;15

northernhemispheredeployment:severedroughtin

sub-SaharanAfricaandIndia;southernhemisphere

deployment:rainfailureinnortheastBrazil,more

hurricanesinNorthAtlantic16​

Marinecloudbrighteninginvolves

Medium

Billions

Years

Decreasedprecipitationandlowertemperatures,

sprayingparticlesintomarineclouds

(for0.8–5.4W/m2)

adverselyaffectscrops.SouthAmericawarmerand

tomakethemmorereflective

dryer;lessrainoverAmazonbasin;moretropical

rainfall;17risktosuddenstop,needtoescalateover

time18

Spacemirrorsarelargemirrorsput

Medium

Trillions

Months

Weatherchanges,potentialdecreaseinbiosphere,

intospace(e.g.,orbitatLagrange

(for<0.6W/m2)

precipitationmaydecreasewithtemperature,regional

point1)toblockandreflectsolar

shadingandsunlightincreaseimpactsagriculture

radiation

SOURCE:RANDanalysiswithcostordersofmagnitudebasedonreviewpublications.19

toachievethelevelofreadinessrequiredforlarge-scaleimplementationoftheseapproaches.11OfthevariousCDRtechnologies,oceanironfertilizationwouldmostreadilyaffecttheclimate,inyearscomparedwithdecadesfortheothergeoengineeringtechnologies,andwouldrequiretheleastinvestment.

MajorSecondaryEffectsofCarbonDioxideRemoval

AlthoughCDRisviewedmorefavorablythanSRMintermsofitssecondaryeffects,itisimportanttoacknowledgetherisksinherentinitsdeployment.Forestationofpreviouslyunforestedareaslikelyrequiresfertilizationandirrigation,whichcouldcausewater

pollution,nutrientrunoff,anddepletionoffreshwatersupplies.Moreover,drasticallychangingthevegetationinaregionthroughforestationwillcausemicroclimatealterationsanddisruptlocalecologicalsystems.Thesenegativeenvironmentaleffectsandland-usedemandsarelikelytobeplacedontheshouldersofdevelopingcountriesbecauseoftheconceptofconservingexistingforestsandplantinginnon-forestedandless-developedareas.

Althoughbioenergywithcarboncaptureandstorageprocessesisstillbeingdeveloped,thereareconcernsthatbioenergyprocesses,aswellasthoseusedtocaptureCO2,wouldthemselvesemitmoreCO2.Likeforestation,bioenergywithcarboncaptureandstoragewouldcreateahigherdemandforagriculturalactivityandfertilizationtofuelthebioenergycomponent,whichcouldleadtoconflict

4

stemmingfromland-rightsdisputes.12Inaddition,theissueofsafedisposalorstorageofcapturedCO2isasignificantconcern,giventhedangerassociatedwithasuddenreleaseofCO2intotheatmosphere.Furthermore,storingCO2undergroundcouldleadtomicroseismicity.13Giventheseconcerns,carefulconsiderationsneedtobemadeaboutwherestoragesitesarelocated.

Directaircapturehassimilarsecondaryeffectsandconcernsasbioenergywithcarboncaptureandstorage.Asthetechnologystandstoday,itwouldtakelargeamountsofenergyandwatertoscaleupdirectaircapturetoalevelthatwouldimpacttheclimate,andthetechnologyalsoinvolvestoxicchemicalsthatpullCO2outoftheatmosphere.Likebioenergywithcarboncaptureandstorage,oncetheCO2isremoved,thereareconcernsaboutthestorageordisposalofbothCO2andtheextractingchemicals.

Finally,oceanironfertilizationhasthepotentialtogeneratesurfacecooling,however,somestudiesindicatethatitcouldactuallyleadtoanincreaseinseasurfacetemperaturesbecausemoreenergyisbeingharvested.Inaddition,oceanironfertilizationcouldcounterproductivelyleadtotheproductionofothergreenhousegases,suchasNOx.Thetechnologycouldalsocauseozonedepletionandecosystemdisruptionthroughoceanacidificationandalgalblooms.Ifimplementedonaglobalscale,modelingstudiespredictthattheoceanwouldloseoxygen,killingfishandotheroceanlife.14AlthoughoceanironfertilizationhasalowercostandfastertimescalethanotherCDRtechnologies,theseareseriousriskstoconsiderbeforeproceedingwithlarge-scaleimplementation.

Withtheexceptionofoceanironfertilization,CDRtechnologiescanbepredominantlyimplementedlocallywithinacountry,wherecross-boundarysecondaryeffectsmightoccuratbordersonaregionalscale.TheintendedclimateeffectswouldbeglobalinreducingglobalGHGconcentrations,similartoreducingGHGemissions.Withoceanironfertilization,itismorelikelythatissuesofinternationalwaters’usewillariseinimplementationatscale.

AlthoughSRMtechnologieswouldhavearelativelyfasterimpactontheclimatethanCDRapproachesandincludelessexpensiveoptions(somebyordersofmagnitude),noneofthesetechnologiesareatahighleveloftechnicalreadiness.CharacteristicofallSRMtechnologies,theywouldnotreduceGHGconcentrations,thecauseofclimatechange,butrathercountertheresultingwarming.Withrespecttostratosphericaerosolinjection,scientistshaveconductedconceptualtestsondifferenttypesofaerosolsanddispersionmethods,thereforeweassessed

ittohavealowtomediumleveloftechnicalreadiness.Stratosphericaerosolinjectionhasyettoundergoformaltestingintheactualstratosphericenvironment.20Marinecloudbrighteningisunderdevelopmentandhasnotbeendemonstratedatscale,withtheexceptionofobservationsofparticleemissionsfromshipscausingbrightstreaksinclouds.21Spacemirrorsexistatasmallscale,buttheyhaveamediumleveloftechnicalreadinessbecauseadditionaltechnologicaldevelopmentwouldbeneededtoconstructthemirrorsatthenecessaryscaleinspace.22

5

MajorSecondaryEffectsofSolarRadiationManagement

PreliminarymodelingstudieshavehighlightedsomepotentialsecondaryeffectsofSRMtechnologies.Theseeffectshavedisincentivizedconsiderationoftheincorporationofthesemethodsintofutureclimatemitigationplans.Modelingofstratosphericaerosolinjections,forexample,hasshownalikelihoodofhigherlatitudewarming,changesinprecipitation,ozonedepletion,oceanacidification,andfoodandwatercontamination.23Furthermore,iftheimplementationofaerosolinjectionssuddenlystops,therewouldbeanabruptincreaseinsolarradiation.Inthemonthsthatfollow,thiswoulddisruptecosystemsandrestarttheclimatechangeimpactsthattheaerosolinjectionswereinitiallysupposedtobemitigatingbecauseGHGsremainintheatmosphereformuchlongerthantheaerosolsthatwouldbeused.24Inaddition,modelingstudieshaveshownthatthelocationinwhichaerosolinjectionsareimplementedwouldinfluencethesecondaryeffects.Ifaerosolinjectionsareimplementedinthenorthernhemisphere,itcouldcauseseveredroughtsinsub-SaharanAfricaandIndia.25Ifitisdeployedinthesouthernhemisphere,however,itcouldcauserainfailureinnortheastBrazilandanincreaseinhurricanesintheNorthAtlantic.26Anothermodelingstudyhasshownthatdifferentregionsacrosstheglobedonotbenefitequallyinresponsetodifferentlevelsofstratosphericaerosolinjection,suchasthosethatwouldbeusedforSRM.27Thesedifferentialeffectsincreasethechancesforsuchdecisionstoappearmalicious.

Thesecondaryeffectsofmarinecloudbrighteningincludeadecreaseinprecipitationandtemperature,whichwouldadverselyaffectagriculturalcrops.Thereare

alsomanyregionaleffectsassociatedwithmarinecloudbrightening,includingwarminganddryinginSouthAmerica,adecreaseinrainfallovertheAmazonbasin,andanincreaseintropicalrainfall.28Likestratosphericaerosolinjections,ifmarinecloudbrighteningissuddenlystopped,theremaybenegativeeffects:Theso-calledterminationshockwouldincludeabruptwarmingandecosystemdisruptioninthefollowingdays.29Itwouldalsobenecessarytoescalatetheimplementationofmarinecloudbrighteningtosustainitseffectovertime.

Finally,spacemirrorscouldpotentiallycauseweatherchangesand,asaresult,adecreaseinglobalbiomass.Astemperaturesdecrease,levelsofprecipitationmayalsodecrease.Becausespacemirrorswillserveasaphysicalshadefromthesun,therewillberegionalshading,inadditiontosunlightincreaseindifferentregions.Thiswilllikelyaffectagricultureandlocalecosystems.Andaswithstratosphericaerosolinjections,implementationchoicesthatimpactcertainregionshavethepotentialtobeperceivedasmalicious.

ThesecondaryeffectsofSRMapproacheshavedisincentivizedtheirincorporationintofutureclimatemitigationplans.Stratosphericaerosolinjectionsandmarinecloudbrighteningcouldconceivablybeimplementedonasmallerscaletolimittheireffectstoaspecificregion,buttheinterconnectednatureoftheclimatesystemmakestheboundary-crossingspreadofsecondaryeffectsextremelydifficulttoavoid.Toachieveeffectsonthescaleoftheglobalclimate,allSRMtechnologieswouldneedtobewidelyimplementedacrosstheglobalcommons,althoughmarinecloudbrighteningismorelimitedinitsabilitytoscaleup.

6

StateoftheScience

Currently,geoengineeringresearchandearly-stagedeploymenteffortsarebeingconductedinmanycountriesaroundtheworld.Geoengineeringresearchhasfocusedonstudyingthetechnicalfeasibilityofvariousgeoengineeringtechnologies,conductingimpactassessments,andconsideringtheethical,legal,andsocialimplications

ofgeoengineeringtechnologies.Themajorityofthisresearchhasbeencarriedoutinacademicandlaboratorysettings.IntheUnitedStates,forexample,HarvardresearchershavelaunchedtheStratosphericControlledPerturbationExperiment(SCoPEx30),whichseekstoclarifytherisksandbenefitsofSRM,andresearchersattheNationalCenterforAtmosphericResearchandthePacificNorthwestNationalLaboratoryhavemodeledtheeffectsofmarinecloudbrightening.31TheGeoengineeringModelIntercomparisonProjectandtheCarbonDioxideRemoveModelIntercomparisonProjectaremodelingthelikelyclimateeffectsofgeoengineering.32Academicresearch

ongeoengineeringisongoinginCanada,India,Japan,Australia,Germany,andtheUnitedKingdom.ResearchprogramsinChinaarealsomodelingtheclimateeffectsofgeoengineeringandconductingimpactassessments.33TheDevelopingCountryImpactsModellingAnalysisforSRMFundeffortprovidesgrantfundingtoscientistsinthesouthernhemispheretoresearchtheimpactofSRM.Inadditiontotheseresearchactivities,early-stagedeploymenteffortsfocusingonforestationhavebeenundertakeninPeruandBrazil.34

GeopoliticalRisksofGeoengineering

Importantly,thedevelopmentandimplementationofgeoengineeringisnotmerelyamatterofscientificandengineeringadvancement,butalsoaquestionofgeopolitics.Internationalgeopoliticaldynamics,andtheinternalpoliticaldynamicsofstates,haveasignificantinfluenceonhowcountriesrespondtoclimatechange,includinghowtheyviewgeoengineering.35Expertsindicatedthattheseresponsescouldplausiblyleadtointernationaltensions,conflict,andevenwar.36

Geoengineering:WhoDecides?

Theprimaryconcernisthatsomecountriesmaydecidetopursuegeoengineeringevenasotherscondemnthoseefforts.Asscholarshaveargued,thisdivergenceresultsbecause“evenoptimalclimateengineeringwouldresultin‘winnersandlosers’:somestateswouldgainrelativetoaworldwithoutclimateengineering,somestateswouldlose,andnostatewouldbeunaffected.”37

Itisworthnotingthatmorepowerfulstatesmightopposegeoengineeringiftheybelievethattheystandtolosemorefromtheengineeredclimatethanthestatusquo.Forexample,Russiacouldbenefitfromawarmingclimateintermsofitsagricultureandpolaractivities.Asitstands,manypowerfulcountries,forexample,thefivepermanentmembersoftheUNSecurityCouncil,arerankedinthetopone-thirdofcountriesleastvulnerabletoclimatechangeandmostreadytoadapt.38Bycontrast,thecountriesthataremostvulnerabletoclimatechangeandmostlikelytobenefitfromgeoengineeringtendtobelowincomeandwithlittleinternationalpoliticalinfluence.Althoughespeciallyvulnerablecountriesmaybeabletoimplement

7

less-expensiveSRMtechnologiesontheirown,39dependingonthelikelyimpactsoftheseefforts,theymaybeopposedbymorepowerfulstates.Moreover,becausecertainSRMtechnologiesarelessexpensivearangeofnon-stateactorscouldunilaterallydecidetoimplementthem,whichwouldrequirestatestorespond.

Tensionsmayalsoarisebetweenhighcarbon-emittingcountries(mostnotablyChinaandtheUnitedStates)andlowcarbon-emittingcountriesbecauseoftheirdifferentlevelsofresponsibilityfortheeffectsofclimatechange.Highcarbon-emittingcountriesmaysupportgeoengineeringtoremovetheneedtoreduceemissions,butlowcarbon-emittingcountriesmayopposesuchgeoengineeringeffortsforanumberofreasons.Forexample,acountrythatemploysSRMinsteadofreducingitsemissionsispostponingorgeographicallydisplacingtheconsequencesofclimatechangewhilefailingtocontributetoalong-termglobalsolution.Incontrast,acountrythatusesCDRinsteadoftraditionalemission-reductionmeasuresisreducingtheamountofgreenhousegasesitcontributes,butitwillneedtoscaleupitsCDReffortswithoutparalleleffortstoreduceemissions.Ineithercase,lowcarbon-emittingcountriesmayarguethathighcarbon-emittingcountrieshavefailedtomeettheirlegalobligationsundertheUNFrameworkConventiononClimateChangeandaretryingtousegeoengineeringtocompensatefortheirfailures.Alternatively,industrializedcountriesintheWestmaygrowincreasinglyfrustratedattheslowpaceofemissionsreductionsinfast-growingnationsinAsia,leadingtotensionsbetweenthetwoblocs.

Evenifstatesagreethatgeoengineeringcanorshouldbeused,potentiallycontentiousissuescouldstillarise.40First,whatistheoptimalclimatethatgeoengineering

activitiesshouldseektoachieve?Ifcountrieshaveadifficulttimereachingagreement,conflictscouldemergeoverglobalconsensusregardingcontrolofthethermostat.41Second,statescouldfightovertheterritoryandresourcesneededtoimplementgeoengineering.SRM,forinstance,couldcreateafutureinwhich“landgrabswillturnintoskygrabsandterritorialdisputeswillextendtothestratosphere.”42Third,statescouldtrytocompelgeoengineeringlaggardsorfree-riderstocontributetointernationalCDReffortsthroughparallelgeoengineeringefforts,muchlikestatestrytocompelemissionsreductionstoday.43Andfourth,tensionscouldriseifstatesblamegeoengineeringbyothers,includingbothSRMandCDR,fortheirownenvironmentalmisfortunes,includingdisruptionstoecosystemsandland-usepatternsandwatercontamination.Geoengineeringactivitiesabroadmayprovideworldleaderswithaconvenientscapegoatwhentheircitizenssufferfromnegativeclimateimpacts,suchasfloodingorcropfailure,evenifthegeoengineeringinterventionisnotthetruecauseoftheirsuffering.44

PotentialforPositiveGeopoliticalOutcomes

Althoughgeoengineeringmayinflamegeopoliticaltensions,itcouldalsoserveasatoolformitigationorresolutionofthosetensions.Foronething,climatechangeitselfposessignificantrisksforinternationalpolitics,includinganincreasedriskofconflictandwarresultingfromnaturaldisastersandresourcescarcity.45Countriescouldtrytoreachagreementstocooperateontheuse

ofgeoengineering,whichcouldeasetensionsthathaveemergedbecauseofdisparateclimateimpacts.Theprocess

8

oftryingtoachieveconsensusongeoengineeringmayitselfleadtogreatercooperationamongstatesonunrelatedissuesofglobalimportance.

MechanismsforManagingInternationalGovernanceChallenges

ExistingInternationalLegalMechanisms

Internationalenvironmentallaw,thebodyoflawmostrelevanttogeoengineering,isasetofrules,treaties,andconventionsthatsetglobalstandardsandobligationsconcerningtheenvironmentforstateparties,suchasenhancedregulationofcarbonemissions,restrictionsonenvironmentalmodification,andtheprotectionofbiodiversity,amongothers.Asconcerngrowsaboutclimatechangeandtheenvironment,theUNandotherinternationalbodieshaveestablishednewlegalmechanismstoaddressrelatedissues.However,thesemechanismshavevaryingandlimitedbindingcapacityonmemberstatesandlackeffectiveenforcementapparatusesandimpl