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2021

4°C, 4°C,

J.B. Ruhl

Robin Kundis Craig

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Recommended Citation Recommended Citation Ruhl, J.B. and Kundis Craig, Robin, "4°C," (2021). Minnesota Law Review. 3297. https://scholarship.law.umn.edu/mlr/3297

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191

Article

4°C

J.B.Ruhl†andRobinKundisCraig††

Introduction..........................................................................................................192 I. Embracing4°C:Why2°CIsTooConservativeforAnticipatoryAdaptationGovernance................................................................................203 A. WhereAreWeNow?TheCurrentIncreaseandTrendsin

GlobalAverageTemperature........................................................204 B. CanWeStayBelow2°C?CarbonBudgets,Coronavirus,and

Uncertainty...........................................................................................205 1. EmissionsCutsSufficienttoHaltWarmingAre

Unlikely..............................................................................................206 2. CarbonBudgetsAlsoSuggestthatthe2°CMitigation

GoalIsUnrealistic.........................................................................211 C. WhereAreWeGoing?CommittedWarmingand

ProjectionsforGlobalAverageTemperatures.......................214 II. Anticipating4°C:WhatDoestheWorldLookLikeBeyond2°C?......................................................................................................217 A. ComingtoGripswithNonlinearChange..................................218 B. AcknowledgingPotentialLimitationsonHumanity’s

AdaptativeCapacity..........................................................................227 C. ImaginingtheUnitedStatesWhentheWorldIs4°C

Warmer....................................................................................................227 III. Adaptingto4°C:ReorientingAdaptationPolicyforAnticipatoryRedesign.............................................................................................................231 A. Resistance,Resilience,andRetreat............................................232 1. Resistance.........................................................................................232

† DavidDanielsAllenDistinguishedChairofLaw,VanderbiltUniversityLaw

School.Copyright©2021byJ.B.Ruhl.†† RobertC.PackardTrusteeChairinLaw,GouldSchoolofLaw,Universityof

SouthernCalifornia.Weappreciate comments receivedonearlydraftsof thisworkduringworkshopsconducted(online)bytheU.C.DavisSchoolofLaw,UniversityofMarylandLawSchool,VanderbiltLawSchool,andVermontLawSchool.Copyright©2021byRobinKundisCraig.

192 MINNESOTALAWREVIEW [106:191

2. Resilience..........................................................................................234 3. Retreat................................................................................................236

B. TheThreeRsVersus4°C.................................................................239 C. ReframingAdaptationforRedesign..........................................244

IV. Governingat4°C:Conceptualizing,Planning,andImplementingRedesignAdaptation.......................................................247 A. DifferentModesofChange:APlanningTypology

forRedesign.............................................................................................251 1. BaselineLinearChange..............................................................253 2. NonlinearChange..........................................................................253 3. CascadesChange...........................................................................255

B. TheToolbox:AnImplementationTypologyforRedesign.............................................................................................255 1. Laissez-Faire...................................................................................255 2. PlanningandProdding...............................................................258 3. PreemptionandMandates........................................................265

C. AnticipatoryGovernance:BuildingFutureScenariosforPolicyStrategyDesign..............................................................269

D. AnInitialStep:CreatingaNationalForesightSystemfor4°CAdaptationPlanning.........................................................................272

Conclusion..............................................................................................................277

INTRODUCTIONInMarch2020,while theworld’sattentionwas focusedonthe

coronaviruspandemic,aninternationalteamofeighty-ninepolarsci-entistsfromfiftyorganizationsreportedthatGreenlandandAntarc-ticaarelosingicesixtimesfasterthantheywereinthe1990s.1Basedonsatellitedata, the research teamconcluded that “[i]f thecurrentmelting trend continues, the regionswill be on track tomatch the‘worst-case’ scenario of the Intergovernmental Panel on ClimateChange(IPCC)ofanextra6.7inches(17centimeters)ofsealevelrise

1. SeeGreenland,AntarcticaMeltingSixTimesFasterThan inthe1990s,NASAGLOB. CLIMATE CHANGE (Mar. 16, 2020), https://climate.nasa.gov/news/2958/greenland-antarctica-melting-six-times-faster-than-in-the-1990s [https://perma.cc/2D2A-CHPG].InApril2021,scientistsreportedthatanunmannedsubmarinehadsim-ilarlyrevealedthatThwaitesGlacierinAntarctica—knownasthe“DoomsdayGlacier”becauseitsdisintegrationcouldinitiatethelossoftheentireWestAntarcticicesheet—has“warmwaterimpingingfromallsidesonpinningpointscriticaltoice-shelfstabil-ity,ascenariothatmayleadtounpinningandretreat.”A.K.Wåhlin,A.G.C.Graham,K.A.Hogan,B.Y.Queste,L.Boehme,R.DLarter,E.C.Pettit,J.Wellner&K.J.Heywood,PathwaysandModificationofWarmWaterFlowingBeneathThwaitesIceShelf,WestAntarctica,7SCI.ADVANCES,Apr.9,2021,at1.

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by2100.”2Onemonthlater,inSiberia,“thesmalltownofVerkhoyansk(67.5°Nlatitude)reached100.4degreesFahrenheit,32degreesabovethe normal high temperature” and “likely the hottest temperatureeverrecorded inSiberiaandalso thehottest temperatureeverrec-ordednorthoftheArcticCircle,whichbeginsat66.5°N.”3Allaroundthetown,theArctictundrawasburning.4Thiswasnotananomaly,butrathertheleadingedgeofatrend.ThroughouttheNorthernHem-isphere, wildfire danger is expanding northward: before enflamingtheArcticin2020,wildfiredevastatedlargepartsofNorway,Sweden,andScotlandinthesummerof2019.5

Theacceleratingicelossandexpandingwildfirezonesarepoten-tialmarkersofwhatareknownastippingpoints—thresholdsalonganonlinearpatternofsystemchangethat,oncecrossed,movethesys-temintoanewsetofpositivefeedbackdynamicsthatacceleratethepaceofchangeandcanbeextremelydifficult toreverse.6Scientistsareincreasinglyconcernedthatwearedangerouslyclosetopassingtheseandmanyotherirreversibleclimatechangetippingpoints,es-peciallywithrespecttotheWestAntarcticicesheet,glaciers,tropicalcoralreefs,theAmazonrainforest,andtheArcticborealforest.7To

2. Greenland,AntarcticaMeltingSixTimesFasterThaninthe1990s,supranote1. 3. JeffBerardelli,ArcticRecords ItsHottestTemperatureEver,CBSNEWS (June23, 2020), https://www.cbsnews.com/news/arctic-hottest-temperature-ever[https://perma.cc/F6C3-3MKL]. 4. Id. 5. SeeScotland,NorwayandSwedenAlreadySeverelyEffectedbyForestFiresDueto theDryWeather in theNorth, CTIF: INT’LASS’NOFFIRE&RESCUESERVS. (Apr. 24,2019), https://www.ctif.org/news/scotland-norway-and-sweden-already-severely-effected-forest-fires-due-dry-weather-north[https://perma.cc/F6C3-3MKL]. 6. SeeMartenScheffer,JordiBascompte,WilliamA.Brock,VictorBrovkin,Ste-phenR.Carpenter,VasilisDakos,HermannHeld,EgbertH.vanNes,MaxRietkerk&George Sugihara,Early-Warning Signals for Critical Transitions, 461 NATURE 53, 53(2009). 7. SeeTimothyM.Lenton, JohanRockström,OwenGaffney,StefanRahmstorf,Katherine Richardson, Will Steffen & Hans Joachim Schellnhuber, Climate TippingPoints—TooRiskytoBetAgainst,575NATURE592,592–95(2019)(correctedApril9,2020).Forexample,thereisevidencethattheGreenlandicesheetisexperiencingmasslossatacceleratingratesandhas“switch[ed]toanewdynamicstateofsustainedmasslossthatwouldpersistevenunderadeclineinsurfacemelt.”MichaleaD.King,IanM.Howat,SalvatoreG.Candela,MyoungJ.Noh,SeongsuJeong,BriceP.Y.Noël,MichielR.vandenBroeke,BertWouters&AdelaideNegrete,DynamicIceLossfromtheGreenlandIceSheetDrivenbySustainedGlacierRetreat,1COMMC’NSEARTH&ENV’T1,1(2020)(correctedSept.4,2020).GlaciersdistinctfromGreenlandandtheAntarcticicesheetalso are experiencing accelerating mass loss. Romain Hugonnet, Robert McNabb,


addanadditionalchaoticpossibility,oncetheseandothersystemstip,theymightsetoffcascadesof transformations inothernaturalsys-tems.8Andyet, ifyouconsultclimatescientists’predictionsfromasrecentlyasadecadeago,noneof theseclimatechange impactsaresupposedtobehappeningyet.9

Noonecanfaultthescientistsofadecadeagoforunderestimat-ingthepaceandintensityofclimatechange.Theywereandstillarestudying a rapidly moving target. For example, the peak annualatmosphericconcentrationofcarbondioxide(CO2),themajordriverofclimatechange,was357partspermillion(ppm)in1990,367ppmin2000,388ppmin2010,414ppmin2020,10and419ppmin2021.11Alloftheselevelsareunprecedentedinthepast800,000years,andthehighest,atover400ppm,hasnotbeenexperiencedbyourplanetforthreemillionyears.12Inaddition,knowledgeandtechnologiesalso

EtienneBerthier,BrianMenounos,ChristopherNuth,LucGirod,DanielFarinotti,Mat-thiasHuss, InesDussaillant,FannyBrun&AndreasKääb,AcceleratedGlobalGlacierMassLossintheEarlyTwenty-FirstCentury,592NATURE726,726(2021). 8. SeeLentonetal.,supranote7,at593;WillSteffen,JohanRockström,Kathe-rineRichardson,TimothyM. Lenton, Carl Folke,DianaLiverman, ColinP. Summer-hayes,AnthonyD.Barnosky,SarahE.Cornell,MichelCrucifix,JonathanF.Donges,IngoFetzer, Steven J. Lade, Marten Scheffer, Ricarda Winkelmann & Hans JoachimSchellnhuber,Trajectories of the Earth System in the Anthropocene, 115 PROC.NAT.ACAD.SCI.8252,8253–54(2018). 9. SeeEysteinJansen,JensHesselbjergChristensen,TrondDokken,KerimH.Ni-sancioglu, Bo M. Vinther, Emilie Capron, Chuncheng Guo, Mari F. Jensen, Peter L.Langen,RasmusA.Pedersen,ShutingYang,MatsBentsen,HelleA.Kjær,HenrikSa-datzki,EvangelineSessford&MartinStendel,PastPerspectivesonthePresentEraofAbruptArcticClimateChange, 10NATURECLIMATECHANGE 714,716–18 (2020) (dis-cussinghowtheArcticiscurrentlyexperiencinganabruptclimatechangeeventthatclimatemodelsunderestimated);AslakGrinsted&JensHesselbjergChristensen,TheTransientSensitivityofSeaLevelRise,17OCEANSCI.181,181(2021)(findingthatfutureprojectionsestimatedonclimatemodelresponsesfallbelowextrapolationbasedonrecentobservationalrecords). 10. MonthlyAverageMaunaLoaCO2,NOAAGLOB.MONITORINGLAB’Y,https://www.esrl.noaa.gov/gmd/ccgg/trends(Aug.5,2021)[https://perma.cc/2HZ4-SA7M]. 11. CarbonDioxidePeaksNear420PartsPerMillionatMaunaLoaObservatory,NOAA RSCH. NEWS (June 7, 2021), https://research.noaa.gov/article/ArtMID/587/ArticleID/2764/Coronavirus-response-barely-slows-rising-carbon-dioxide [https://perma.cc/GE2J-WWGA]. 12. Rebecca Lindsey, Climate Change: Atmospheric Carbon Dioxide, NOAA CLI-MATE.GOV (Aug. 14, 2020), https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide [https://perma.cc/2G3K-LT7Z];M.Willeit,A.Ganopolski,R.Calov&V.Brovkin,Mid-PleistoceneTransitioninGlacialCyclesExplainedbyDecliningCO2andRegolithRemoval,SCI.ADVANCES,Apr.3,2019, at 1; see also Climate Change 2021: The Physical Science Basis,

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areimprovingasresearchersobserveclimatechange,inmanycasesrevealingthatprojectionswereunderestimatingthepaceofchange.13It is thusnowonder thatasresearcherskeepstudying theongoingchangesinnaturalsystems,theyarefindingthatimpactsarehittingharderandfasterthanpreviouslyexpected.14

This trend has significant and potentially dire implications forgovernanceandlaw.Climatechangedisruptionswillextendnotonlytoecologicalsystems,buttosocialsystemsaswell,includingsystemsofgovernance.15ItwouldbenaïvetobelievethatgovernanceintheUnitedStateswillbeimmune;indeed,democraticsystemsofgovern-ancemaybeparticularlyunstableinthefaceoftherelentlessdisrup-tions caused by climate change. Recognizing that this is a weightyclaiminneedofsolidsupport,thisArticledoesnotmincewords.Weleanheavilyonscientificfindingsreportedinleadingpeer-reviewedjournals,16theamalgamofwhichpaintsapictureofournation’s(andtheworld’s)futurethatisnothingshortofapolicynightmare.Gettingthepolicieswrong—thatis,failingtoanticipateandadaptivelyplanforthatfuture—presentsanexistentialthreattodemocraticgovern-ance.

Tobesure,policydisciplineshavealreadygrown farmoreso-phisticatedintheirunderstandingofclimatechangegovernancecom-paredto,say,thedawnofthe21stcentury,andtheseverityofclimate INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE 9 (2021) https://www.ipcc.ch/re-port/ar6/wg1/downloads/report/IPCC_AR6_WGI_Full_Report.pdf[https://perma.cc/AJJ2-MLAK][hereinafter2021IPCCPhysicalScienceReport](“[I]n2019,atmosphericCO2concentrationswerehigherthanatanytimeinatleast2mil-lionyears(highconfidence),andconcentrationsofCH4andN2Owerehigherthanatanytimeinatleast800,000years(veryhighconfidence).”). 13. SeegenerallyMichaelOppenheimer&RichardB.Alley,HowHighWilltheSeasRise?,354SCIENCE1375,1375–76(2016)(notingthatprojectionsofsealevelrisekeepgettinghigherbasedonimprovedknowledgeofdynamicalprocesses). 14. SeegenerallyTheOceanandCryosphereinaChangingClimate:ASpecialRe-portoftheIntergovernmentalPanelonClimateChange,INTERGOVERNMENTALPANELONCLIMATE CHANGE 85 (2019), https://www.ipcc.ch/site/assets/uploads/sites/3/2019/12/SROCC_FullReport_FINAL.pdf[https://perma.cc/C6XJ-KNAJ][hereinafter2019IPCCOcean&IceReport](“[E]achofthelastthreedecadeshasbeensuccessivelywarmerattheEarth’ssurfacethananyprecedingdecadesince1850.”). 15. Id. 16. Althoughneitherofusisaclimatescientist,oneofusholdsadoctoraldegreeinhumangeography,andtheotherisatrainedsciencewriterwithadoctoraldegreethatexploredtheincorporationofscienceintoliterarydescriptionsofsocialandeco-logicalchange.Bothofusregularlypublishworkinscientificjournals,oftenaspartofinterdisciplinaryteamsincludingscientistsfromthenaturalandsocialsciences.Wefeeladequatelyequippedtocollect,evaluate,andsynthesizetheavailableclimatesci-enceforapolicyaudience.


change is broadlymotivating policy discourse. There is nowwide-spread agreement that both mitigation—that is, efforts to reducegreenhouse gas emissions and the concentration of anthropogenicgreenhousegases in theatmosphere17—andadaptation—whichen-compasseseffortstoadjusthumanbehaviortoclimatechange’suna-voidable alterations18—must be concurrent governance efforts.19Moreover,thoseeffortsmustbecognizantofeachother,becausemit-igationandadaptationstrategiesinteract,sometimesworkingintan-demtoproduceco-benefits(forexample,waterconservationgener-allyreducesenergyconsumption)butsometimesinvolvingtrade-offconflicts(forexample,subsidizingbiofuelsattheexpenseoffoodse-curity).20Finally,becausebothclimatechangemitigationandclimatechangeadaptationrequiregovernanceeffortsatmultiplescales,fromlocaltointernational,coordinationoftheseeffortsislikelytobecomeanincreasinglyimportantpartoftheoverallclimatechangegovern-ancechallenge.21

Sofar,sogood.Buthere’stherub:whichfutureshouldgovern-mentsandothergovernanceentitiesbecoordinatingabout?Climatechange adaptation inherently requires present governance institu-tionsandarrangementstoanticipatefutureconditionsthataredistantintime,inconstantflux,riddledwithuncertainty,andunlikeanyex-periencedinrecordedhumanhistory.Theconventional“predictandplan”modeofgovernanceisstretchedbeyonditscapacityundersuch

17. SeeClimateChange2014:SynthesisReport,INTERGOVERNMENTALPANELONCLI-MATE CHANGE 17 (2014), https://www.ipcc.ch/site/assets/uploads/2018/02/SYR_AR5_FINAL_full.pdf[https://perma.cc/XFT5-EKAN]. 18. Id.at19. 19. Id.at17. 20. SeegenerallyMiaLandauer,SirkkuJuhola&MariaSöderholm,Inter-Relation-shipBetweenAdaptationandMitigation:ASystematicLiteratureReview,131CLIMATICCHANGE505,505–17(2015)(summarizingresearchonmitigationandadaptationin-ter-relationships); JamesE.Parker-Flynn,TheIntersectionofMitigationandAdapta-tion inClimateLawandPolicy,38ENVIRONSENVT’LL.&POL’YJ.1(2014)(discussingsynergiesandtrade-offs);AyyoobSharifi,Co-BenefitsandSynergiesBetweenUrbanCli-mateChangeMitigationandAdaptationMeasures:ALiteratureReview,SCI.TOTALENV’T,Jan.1,2021,at9–15(focusingonthesynergies);AyyoobSharifi,Trade-OffsandCon-flictsBetweenUrbanClimateChangeMitigationandAdaptationMeasures:ALiteratureReview,J.CLEANERPROD.,Dec.10,2020,at7–12(focusingonthetrade-offs). 21. See,e.g., ElizabethBurleson,AClimate of Extremes: Transboundary ConflictResolution,32VT.L.REV.477,496,501(2008)(notingtheagreementwithinboththeUnitedStatesNationalAcademyofSciencesandtheinternationalcommunitythatco-ordinationof climate change adaptation andmitigation is necessary).See generallyKatherineTrisolini,HolisticClimateChangeGovernance:TowardsMitigationandAdap-tationSynthesis,85U.COLO.L.REV.615(2014).

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conditions. Scholars in the planning and policy sciences thus havecalledforanewformofgovernance,whichtheycallanticipatorygov-ernance,toreflectthechallengeofformulatingclimateadaptationpol-icystrategiesinthepresentthatarebuiltaroundarangeofdynamicpossiblefuturescenariosandrequireconstantmonitoringandpolicyadjustment.22Thecrucialfirststepinanticipatorygovernanceforcli-matechangeadaptation,therefore,isdecidingwhatrangeofscenar-iostouse.

Untilrecently,theanswerwasstraightforward,drivenbyauni-fiedvisionofthefuturebasedonahardlinegoalforclimatemitigationpolicy.Thestandardpolicygoalforthemitigationmodalityhasbeentoworkrelentlesslytocontaintheglobalaverageincreaseintemper-atureto1.5°Cabovepre-industriallevelsideally,andto2°Catworst(2.7°Fto3.6°F).23Thisisthemitigationgoalofmultipleorganizationsandinternationalagreements.Underthe2015ParisAccord,forexam-ple,nearlyeverysignatorycountrypledgedtokeepglobaltempera-tures“wellbelow”2°Cabovepre-industriallevelsandto“pursueef-fortstolimitthetemperatureincreaseto1.5°C.”24 22. See,e.g.,KarlijnMuiderman,AartiGupta,JoostVervoort&FrankBiermann,FourApproachestoAnticipatoryClimateGovernance:DifferentConceptionsoftheFu-tureandImplicationsforthePresent,11WIRESCLIMATECHANGE,Oct.9,2020,at2;RayQuay,AnticipatoryGovernance:AToolforClimateChangeAdaptation,76J.AM.PLAN-NINGASS’N496,498–99(2010);JoostVervoort&ArtiGupta,AnticipatingClimateFu-tures ina1.5°CEra:TheLinkBetweenForesightandGovernance, 31CURRENTOP. INENVT’LSUSTAINABILITY104,105(2018).Anticipatorygovernancetheoryoriginatedinandhasbeeninfluentialinthenanotechnologyrealm.See,e.g.,DavidH.Guston,Under-standing“AnticipatoryGovernance”,44SOC.STUD.SCI.218,219(2014).Formoredetailonanticipatorygovernancetheory,seeinfraPartIV.C–D. 23. TheIPCCtraditionallydefinesglobalmeansurfacetemperature(“GMST”)us-ingaweightedaverageofnear-surfaceairtemperaturesoverland(“SAT”)andseasur-facetemperaturesovertheocean(“SST”).GlobalWarmingof1.5°C,INTERGOVERNMEN-TALPANELONCLIMATECHANGE 56 (2018),https://www.ipcc.ch/site/assets/uploads/sites/2/2019/06/SR15_Full_Report_High_Res.pdf [https://perma.cc/5L7C-M4WK][hereinafter 2018 IPCC 1.5°C Report]. Increases in this average temperature are ahandywaytoreferencehowmuchtheplanetasawholehaswarmed,but—likemostmeans—thisaveragedoesnotnecessarilyreflecttheactualtemperatureconditionsofanyparticularplaceorthewarmingthatagivenplacehasexperienced.TheIPCC“de-fines‘warming’,unlessotherwisequalified,asanincreaseinmulti-decadeglobalmeansurface temperature (GMST) above pre-industrial levels. Specifically,warming at agivenpointintimeisdefinedastheglobalaverageofcombinedlandsurfaceairandseasurfacetemperaturesfora30-yearperiodcenteredonthattime,expressedrela-tivetothereferenceperiod1850–1900....”Id. 24. The Paris Agreement, U.N. CLIMATE CHANGE (as viewed Jan. 9, 2021),https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement[https://perma.cc/6DX7-JSJC].SeegenerallyYunGao,XiangGao&XiaohuaZhang,The


Adaptationpolicyhasmostly followedmitigationpolicy’s lead,focusingonthemeasuresneededtoadjusttoaworldthatis1.5°to2°Cwarmerthanpre-industrialtimes.25Tobesure,adaptationwillbenecessary,evenforthatfuture.Forexample,theIPCChasspelledoutingreatdetailtheadaptationsthatwouldberequiredasawayofem-phasizing the need to try to keep global warming to below 2°C.26Framedthisway,adaptationpolicyhassupportedmitigationpolicythroughtheirunifiedviewofthefuture.

However, the2°Cassumptionofmaximumwarmingno longerworksintheadaptationmodality.AswedetailinPartI,despitethecontinuedinternationalhomagetothismitigationgoal,mostcontem-poraryevaluationsoftheprogressofclimatechangeindicatethattheincreaseinglobalaveragetemperaturewillexceed2°Candprobablyexceed3°Cthiscentury,27withincreasescontinuingbeyond2100.28GiventhetrajectoriesofCO2atmosphericconcentrationsandanthro-pogenicemissions(nottomentionadditionalemissionsfromtheef-fectsofclimatechangeonecosystems),the2°Climitislikelyachieva-bleonlyifboththesensitivityofclimatetoCO2concentrationsgoingforwardislow29andeither(1)technologydevelopedinthenextfiftyyearsmakessubstantialnet-negativeemissionspossibleonaglobalscale,or(2)globalemissionspeakrapidlyandthenfallforthenextseveraldecadesatratesneverbeforevoluntarilyachievedbyanysin-glenation.30AsweexplaininPartI,theseareunrealisticassumptionsatbest.31 2°CGlobalTemperatureTargetandtheEvolutionoftheLong-TermGoalofAddressingClimateChange—FromtheUnitedNationsFrameworkConventiononClimateChangetotheParisAgreement, 3ENG’G272,272 (2017) (providingahistoryof the2°Cgoal);MarkNew,DianaLiverman,HeikeSchroder&KevinAnderson,FourDegreesandBe-yond:ThePotential forGlobalTemperaturetoIncreaseFourDegreesandItsImplica-tions,369PHIL.TRANSACTIONSROYALSOC’YA6,7–8(2011). 25. Seegenerally THELAWOFADAPTATIONTOCLIMATECHANGE:U.S.AND INTERNA-TIONALASPECTS(MichaelB.Gerrard&KatrinaFischerKuheds.,2012)[hereinafterLAWOFADAPTATION](providingacomprehensivesurveyofUnitedStatesadaptionlawandpolicy).WereviewadaptationpolicydesigninPartIII,infra. 26. 2018IPCC1.5°CReport,supranote23,at5. 27. CélineGuivarch&StéphaneHallegatte,2CorNot2C?,23GLOB.ENVT’LCHANGE179,180–86(2013)(summarizingthegrowingperspectivethat2°Cisnotattainable). 28. Foradiscussionofevidencesupportingthisassessment,seeinfraPartI. 29. Fordetailsonclimatesensitivity,seeinfraPartI.C. 30. Guivarch&Hallegatte,supranote27,at186. 31. Importantly,however,whilewe find the2°Cmitigationgoalunlikely tobemet,webotharecommitted toaggressivemitigationpolicy,andany failure tostaybelow2°Cwarmingshouldspurredoubledeffortstostabilizetheplanetaryclimate

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Given this likely trajectory, adual-mindedapproach to climatechange,politicallydifficultasitis,isnecessarytosimultaneouslygivetheplanetthebestfuturepossible(mitigationgovernance)whilepre-paringhumanity for theworstof theprobablerealities (adaptationgovernance).Inotherwords,mitigationpolicyandadaptationpolicycannolongeroperateunderaunifiedviewofthefuture.Rather,likeSchrödinger’scat,governanceentitiesmustsimultaneouslyresonatein two different climate futures—amitigationmodality aimed at aceilingof2°Candanadaptationmodalitypreparedforanincreaseinglobalaveragetemperatureatleastashighas4°C.32

WhattheUnitedStatesandothernationsaredoingtoadapttoa2°Cfuturewillnotbeenoughforthiswarmerworld.AsweexplaininPartII,researchincreasinglyidentifieswarmingof2°Casalikelytip-ping-point threshold formany ecological systems.33 Evidence fromthehistoricalrecordsandadvancedmodelingdepictwarmingbeyond2°Casgamechanging,andthemultiplecrossingsofmultiplethresh-olds will require a different kind of adaptation. Moreover, radicalchangesintheecologicalsystemswilllikelytriggertippingpointsinsocialsystems,aswell.Asastartlingexample,attheextremetemper-ature increase of 7.5°C that could occur under a business-as-usual

systematassmallaglobalaveragetemperatureincreaseaspossible.

Inaddition,weacknowledgebutdonotengageheretheemergingdebateoverwhethermitigationpolicyshouldcontinue to frame itselfaround the1.5°–2°Cgoal.Theconcernisthatasthe2°Ctargetlosescredibility,adheringtoitunderminesinter-nationalnegotiationsand,worse,wouldleadtoinsufficientmitigationmeasures.Id.at179.Rather,ourfocusisontheneedtobeginthinkingaboutthegovernancenecessarytosuccessfullyadapttoafarwarmerworld—a4°Cfuture.

Finally,weleavetothesidethedebateovergeoengineering,whichweconsidertobeamitigationstrategyratherthananadaptationstrategy.See,e.g.,NAT’LACAD.OFSCI.,ENG’G,&MED.,REFLECTINGSUNLIGHT:RECOMMENDATIONSFORSOLARGEOENGINEERINGRESEARCHANDRESEARCHGOVERNANCE (2021); PaulVoosen,U.S.Needs SolarGeoengi-neeringResearchProgram,ReportSays,372SCIENCE19(2021)(summarizingtheNASreport). See generally Albert Lin,Does Geoengineering Present aMoral Hazard?, 40ECOLOGYL.Q.673(2013)(providingathoughtfuloverviewofgeoengineeringanditsimplicationsforclimatepolicy).Wedonote,however,thatthegeoengineeringtech-niquesthatdonotdirectlyreduceatmosphericCO2concentrations,suchassolarradi-ationmanagementandsomeformsofaerosolcooling,failtoaddresssomeimportantimpacts,especiallyoceanacidification,andhencemerelyshifttheadaptationproblemratherthaneliminate it.Seegenerally,e.g.,PhillipWilliamson&CarolTurley,OceanAcidificationinaGeoengineeringContext,370PHIL.TRANSACTIONSROYALSOC’YA4317(2012). 32. See J.B.Ruhl,Schrödinger’s Climate, JDSUPRA (May19, 2020), https://www.jdsupra.com/legalnews/schrodinger-s-climate-32775 [https://perma.cc/4QCJ-FGC6]. 33. Steffenetal.,supranote8.


scenariowithnomitigation,by2070one-thirdoftheworld’spopula-tionwouldexistinanannualtemperaturerangepresentlyfoundononly0.8%oftheworld’s landmass,mostlyintheSaharandesert, iftheyremainedwheretheycurrentlyare.34Itis,however,unlikelytheyallwouldremaininsitu,meaningthatmasshuman(andotherspe-cies)migrationisasignificantadaptationissue.Adaptationateverylevelofwarmingthusisbestthoughtofasevolvingininterdependentsocial-ecologicalsystems,andthisevolutionarydynamicwillbecomemore intense and rapid above2°C.Tobe effective, adaptation thuscannotcontinuetobeconceptualizedasanincrementally linearex-trapolation of current efforts if social-ecological systems undergononlinearchangebeyond2°C.35

Assuggestedabove,however,theunifiedvisionbindingadaptionandmitigationpolicytogetherhaskeptadaptationpolicyandplan-ningfocusedona2°Cfuture.AsweoutlineinPartIII,thisunifiedvi-sionofa2°CfuturehasplayedoutinadaptationpolicyintheUnitedStatesandmanyothernationsthroughthreeinterconnectedmodesofadaptationdeployedprimarilyatthelocalscale.36Thefirstis,wherepracticable, toresist the impactsof climatechange, suchasbycon-structinghardseawallstofendoffrisingsealevels.37Thesecondistobuildtheresilienceofsocial-ecologicalsystemstotheharmsofclimatechange, such as by improving urban capacity to respond to heatwaves.38Thethirdmodeistoretreatfromunavoidableimpacts,suchasinareaswherecoastalresistanceusingseawallsisnotpractical.39Usingthese“ThreeRs,”conventionaladaptationpolicyenvisionstheend product as something close to life before warming and, im-portantly,inthesameplace.

34. ChiXu,TimothyA.Kohler,TimothyM.Lenton,Jens-ChristianSvenning&Mar-tenScheffer,FutureoftheHumanClimateNiche,117PROC.NAT.ACAD.SCI.11350,11350(2020). 35. MarkStaffordSmith,LisaHorrocks,AlexHarvey&CliveHamilton,RethinkingAdaptation fora4°CWorld, 369PHIL.TRANSACTIONSROYALSOC’YA196,196 (2011),(“Adaptingtoglobalwarmingof4°Ccannotbeseenasamereextrapolationofadap-tationto2°C;itwillbeamoresubstantial,continuousandtransformativeprocess.”). 36. Fordescriptionsofeach,seeinfraPartII.A. 37. SeeinfraPartIII.A.1. 38. SeeinfraPartIII.A.2. 39. SeeinfraPartIII.A.3.Weacknowledgethatthereareotherwaystonamethesemodalities.See,e.g.,KatharineJ.Mach&A.J.Siders,ReformingStrategic,ManagedRe-treatforTransformativeClimateAdaptation,372SCIENCE1294,1294(2021)(“Numer-ousadaptationactions—oftencategorizedasresistance,accommodation,avoidance,retreat,andadvance—canaddressclimaterisks.”).Our“ThreeRs”encompassallofthesemodalities,butinfewercategories.

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As the prospect of holding temperature increase to under 2°Cerodes,however,insituadaptationusingtheThreeRscannolongerremainthepresumednorm.Manyhumanbeingsandthecomplexso-cial-ecologicalsystemsinwhichtheycurrentlyexist,includingintheUnitedStates,willnotbeabletoremainintheirsameconfigurationsinthesamelocationsina“beyond2°C”world.40Astheserisksbecomerealities,theThreeRsareunlikelytobesufficient,andtheymayevenbe futile in someregionsof thenation.41Manyhumans facing suchconditionswillrespondbyadaptingwiththeirfeet.42Althoughlegalscholarshaverecognizedthatpotentialaslargelyaninternationalhu-manrightsandimmigrationproblem,43fewhaveexploredtheimpli-cationsofsubstantialclimate-induceddomesticmigrationwithintheUnitedStates.44

In short,moving past 2°Cwill require adding a fourth climatechangeadaptationmode toU.S.policy—redesign.By “redesign,”wemean transformational adaptationmeasures as radical as the paceandintensityofchangingconditionsbeyond2°C,measuresthatwillbeneededtoreconfigureandrelocateournation’spopulationdistri-bution,landuses,infrastructure,economicandproductionnetworks,naturalresourcemanagement,andothersocial,ecological,andtech-nological systems.45 The redesign adaptationmode anticipates, re-spondsto,designs,andfacilitatesthisrelocationandreconceptionofpopulation, infrastructure, agriculture, and other social-ecologicalsystemcomponents.

Asmuchastheresist,resilience,andretreatadaptationmodeshaveposeddifficultgovernancechallengesalready,46thegovernancestakesina4°Cworldthatrequirestheredesignmodeofadaptationarepotentiallyexistential.Amongthesocialsystemssubjecttomas-sivedisruptionandinneedofadaptation,governancesystemsareof

40. SeeinfraPartII(discussingtheseandotherlikelyimpacts). 41. SeeinfraPartIII(discussingthegrowingbodyofresearchonthistheme). 42. See infra Part II.B (discussing research focusingon climate-inducedmigra-tion). 43. SeegenerallyElizaPan,ReimaginingtheClimateMigrationParadigm:Bridg-ingConceptualBarrierstoClimateMigrationResponses,50ENVT’LL.1173(2020). 44. Foranotableexception,seegenerallyJessicaOwley,Climate-InducedHumanDisplacementandConservationLands,58HOUS.L.REV.665(2021)(exploringtheop-portunitiesandconstraintsforusingconservationlandstomeetinternationalanddo-mesticclimate-migrantneedsintheUnitedStates). 45. SeeinfraPartIII.C(discussingtheredesignadaptationmode). 46. MarkT.Gibbs,WhyIsCoastalRetreatSoHardtoImplement?Understandingthe Political Risk of Coastal Adaptation Pathways, 130OCEAN&COASTALMGMT. 107,108–12(2016)(describingthecontroversiessurroundingtheretreatmode).


foremostconcern.Specifically,ifgovernmentsdonotimplementre-designadaptationeffectively,riotinginthestreets—orworse—isanall-too-likelyresponsetomanyotherdisruptionsthatwilloccurastheworldincreasinglywarms.Toavoidorminimizethatsocialupheaval,engagingnowinanticipatoryadaptationtoaworldthatwillseemorethana2°Cincreaseinglobalaveragetemperature,whilenotcostless,will give human societies like the United States the best chance ofavoidingabreakdownindemocraticgovernance.

ThequestionthisArticle thusengages,perhapsquixotically, is:whatdoesdemocraticgovernanceoftheUnitedStatesina4°Cworldlook like?We set out through this Article to begin a robust dialogabouthowgovernanceintheUnitedStatescanadapttosuccessfullycopewiththatscenario,where“success”means:(1)adaptingtoex-tremeclimatechangeasanationwithouttransitioningoursystemofgovernancetoeitherauthoritarianismortribalism;while(2)provid-ingopportunitiesandsupportforthoseindividualsandcommunitiesthatotherwisefacesignificantrisksofbeingignored,overrun,forgot-ten,leftbehind,orotherwisefurthermarginalized;and(3)stillstriv-ingtoimprovetheresilienceoftheecologicalcomponentsofthemanysocial-ecologicalsystemsthatweinhabit;and(4)buildingandretain-ingthecapacitytocontinueadaptingdemocraticgovernancetoper-petuallyevolvingsocial-ecologicalconditions.Thisisatallorder,tobesure,but if success in the faceofdauntingglobalconditionscanbecondensedtothegoalof“stayinginthegame,”47thesefourconditionsseemnecessary.

To frameandsparksuchadialog, thisArticleproceeds in fourparts.PartIsurveysthecontemporaryscienceshowingwhythe2°Cgoalislikelynolongerfeasible,anda4°Cworldisarealpossibility.PartIIleveragesscientificprojectionsofconditionsatbeyond2°Ctoenvisionthe4°Cworld,includinghowitplaysoutacrosstheUnitedStates,albeitrecognizingtherearekeyuncertaintiesinthoseprojec-tions.PartIIIoutlinesthecurrentThreeRsadaptationpolicymodesandmakesthecasethat,whiletheywillcontinuetobenecessarybe-yond2°C,theywillbeinsufficienttohandlethescopeandintensityofnecessaryadaptations.Itthenintroducestheredesignmodalityofad-aptation.

Buildingonthisfoundation,PartIVtranslatestheforegoingintotwopolicytypologiestofacilitatedesignoflawandpolicyforantici-patory governance of climate change adaptation for the 4°Cworld.

47. JosephA.Tainter,SocialComplexityandSustainability,3ECOLOGICALCOMPLEX-ITY91,100(2006).

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Onetypologydescribesdifferentredesignchallengesbasedonthreemodesofchange—linear,nonlinear,andcascading.Theothertypol-ogyoutlinesdifferentpossiblegovernanceresponses,rangingfromal-lowingprivatemarketstoguideadaptationtocentralizedtop-downplanning.PartIVthenmergesthetwotypologiestoidentifyscenariosthatmustbeanticipatedwhendesigningadaptationgovernancere-sponses.Thisanalysisleadstotheconclusionthat,formanyredesignchallenges,theUnitedStatesmaybebestservedbyacoordinatedna-tionalplanakintothemobilizationthatoccurredatthestartofWorldWarII.

PartIVthenconcludeswithsuggestionsforhowacreationofanationalscienceandpolicyresearch“foresightsystem”canbegintolayfoundationsfordesigningsuchananticipatorynationalplanninginitiative.Weproposesuchaninitiativebeanchoredinanonregula-tory, science-based, interdisciplinary federal bureau charged withproducingpolicy-relevantscenariosofhowclimateadaptationcouldunfoldintheUnitedStatesina“beyond2°C”world.Modelingofcli-matechangeimpacts,anextensiveundertakingalready,doesnotre-vealhowhumanswillrespondtothoseimpacts.Givenhowunprece-dentedconditionsbeyond2°Cwillbecome,thehumanresponsesarelikely to be just as unprecedented. Modeling only climate impactsthemselvesthusprovidesonlyhalfthepicturenecessaryforourna-tion’sclimateadaptationpolicy.

Putbluntly,ifthemountingbodyofsciencepointinginthedirec-tionofmovingbeyond2°Cprovestobecorrect,itwouldbehooveournationtohavebegunenvisioninghowto“stayinthegame”wellbe-forewecrossthe2°Cthreshold.Todootherwise—tocountonthede-scriptionhereinofwhatliesaheadturningouttobewrong,oronso-cietytodesigneffectivesolutionsontheflyifitturnsouttoberight—isagambleweconsidernotworthtaking.

I.EMBRACING4°C:WHY2°CISTOOCONSERVATIVEFORANTICIPATORYADAPTATIONGOVERNANCE

AsnotedintheIntroduction,thisArticle’sscience-basedcentralpremiseisthatitishighlyunlikelythattheworldwillachieveits“be-low 2°C” goals for global averagewarming. This Part defends thatpremise,providinganoverviewofthescienceregardingtheworld’slikelyclimatechangefuture.Itbeginswiththeplanet’scurrenttem-perature and atmospheric greenhouse gas concentration status, aswellasanoverviewoftrends.Itthenexploresthemorecomplicatedissueofwhathumanswouldhavetodotokeepglobalaveragetem-peraturebelow2°C,recognizingthatsuchprojectionsaremadeina


contextofuncertaintyandbestguessesbutneverthelessconcludingthatanysucheffortsareunlikelytosucceed.

A. WHEREAREWENOW?THECURRENTINCREASEANDTRENDSINGLOBALAVERAGETEMPERATURE

Theyear2019wasthesecondhottestyearonrecord,atleastatthemomentwearecomposingthisArticle,48and,asofAugust2021,accordingtotheIntergovernmentalPanelonClimateChange(IPCC),“[e]achof the last fourdecadeshasbeensuccessivelywarmer thanany decade that preceded it since 1850.”49 In 2019, global averagetemperaturewasalready1.15°C(2.07°F)abovethepre-industrialav-erage.50 Inotherwords,theplanetisalreadymorethan76%ofthewaytobeing1.5°Cwarmer,onaverage,or57.5%ofthewaytobeing2°Cwarmer.

Moreominously,“[t]heglobalannualtemperaturehasincreasedatanaveragerateof0.07°C(0.13°F)perdecadesince1880andovertwicethatrate(+0.18°C/+0.32°F)since1981.”51Atthecurrentratesof increase,globalaveragetemperatureswillbe1.5°Cwarmerthanpre-industrial levels by 204052 and 2°C warmer by roughly 2067.However,theratesofwarmingarealsostillaccelerating,and“[e]sti-matedanthropogenicglobalwarmingiscurrentlyincreasingat0.2°C(likelybetween0.1°Cand0.3°C)perdecadeduetopastandongoingemissions(highconfidence).”53

Asbadasthatstoryis,globalaveragetemperatureincreasesarenotalwaysthemostrelevantnumbersforclimateadaptationgovern-ance.AstheIPCCobservedin2018,“Warminggreaterthantheglobalannualaverage isbeingexperienced inmany landregionsandsea-sons,includingtwotothreetimeshigherintheArctic.”54Ofparticularrelevance,temperaturesoverlandsurfaces,wheremostpeoplelive,

48. Rebecca Lindsey & LuAnn Dahlman, Climate Change: Global Temperature,NOAA CLIMATE.GOV (Mar. 15, 2021), https://www.climate.gov/news-features/understanding-climate/climate-change-global-temperature[https://perma.cc/EWV6-CGKP]. 49. 2021IPCCPhysicalScienceReport,supranote12,at5. 50. SeeLindsey&Dahlman,supranote48;seealso,2021IPCCPhysicalScienceReport, supra note12, at5 (indicating that temperatures in thedecade2011–2020were0.95°Cto1.20°Cwarmerthanin1850–1900). 51. SeeLindsey&Dahlman,supranote48. 52. See,e.g.,2018IPCC1.5°CReport,supranote23,at4(“Globalwarmingislikelytoreach1.5°Cbetween2030and2052ifitcontinuestoincreaseatthecurrentrate.”). 53. Id. 54. Id.

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areincreasingfasterthanglobalaveragetemperature,whichismod-eratedbytheocean’scapacitytoabsorbheat.55

TheIPCCreportedin2021thatmeanlandsurfaceairtempera-turehasincreasedanestimated1.59°C(withthepossiblerangebeing1.34–1.83°C),whiletemperaturesovertheoceanhaveincreasedonlyabout0.88°C (withapossible rangeof0.68–1.01°C).56Vividly illus-tratingthisterrestrialdifferential,in2019theWashingtonPostcom-piledmultipledatasourcestoproduceamapshowingthatoverone-tenthoftheglobehasalreadyexperienceda2°Cincrease,andmostoftheUnitedStateswestoftheMississippiRiverplusalargeswathoftheSoutheasthasalreadyexperienceda1.5°Cincrease.57Muchoftheterrestrialworld,inotherwords,hasalreadyexceededthemoream-bitiousoftheinternationalclimatechangemitigationgoals.

B. CANWESTAYBELOW2°C?CARBONBUDGETS,CORONAVIRUS,ANDUNCERTAINTY

Givenwhereconditionsstandnow,howrealisticisthe2°Cceilingmitigationgoal?Theanswerdependson three factors: (1) thepro-spectofsubstantiallyandrapidlyreducingglobalnetemissions;(2)the total additional emissions that can be accepted beforeatmosphericcarbondioxideconcentrationspushtemperaturespast2°C;and(3)therangeofuncertaintyinboththosecalculations.Basedoncurrentmodels,noneofthesefactorsbodeswellformeetingthe2°Cclimatemitigationgoal.58

55. Id. 56. 2021IPCCPhysicalScienceReport,supranote12,at5;seealsoClimateChangeandLand,INTERGOVERNMENTALPANELONCLIMATECHANGE9(2019),https://www.ipcc.ch/site/assets/uploads/2019/11/SRCCL-Full-Report-Compiled-191128.pdf[https://perma.cc/5X3X-YHXU][hereinafter2019IPCCLandReport](similarlyreport-ing that temperatures over land had increasedmore than global average tempera-tures). 57. ChrisMooney&JohnMuyskens,2°C:BeyondtheLimit,WASH.POST(Sept.11,2019), https://www.washingtonpost.com/graphics/2019/national/climate-environment/climate-change-world/?itid=lk_inline_manual_1&itid=lk_inline_manual_1&itid=lk_interstitial_manual_6[https://perma.cc/VR7B-YHW9]. 58. SeeMICHAELP.VANDENBERGH& JONATHANM.GILLIGAN,BEYONDPOLITICS:THEPRIVATEGOVERNANCERESPONSETOCLIMATECHANGE37–63(2017)(leadingtothecon-clusionthatextensiveprivateinstitutionresponseswillbeneededinadditiontopublicgovernance and that “[w]e are pessimistic about the possibility ofmeeting the 2°Cgoal”).Whileweagreethatprivateinstitutionswillplayanimportantroleinclimatemitigationandadaptation,ourfocushereinisonpublicadaptationgovernance.


1. EmissionsCutsSufficienttoHaltWarmingAreUnlikelyReducinganthropogenicgreenhousegasemissions,whileanec-

essary firststep, isnotenoughto immediatelystopclimatechange.Carbondioxidelingersintheatmosphereforalongtime—ontheor-der of centuries.59 Climate change will be an issue as long asatmospheric CO2 concentrations remain high, trapping more heatclose to the Earth’s surface. Reversing the process significantlyenoughtoquicklychangetheplanet’swarmingprocesseswillrequireherculeaneffortsby theworld’snationsover thenext two to threedecades60—anunlikelyfuturerecentlymademoreunlikelybythefactthatnationswillpresumablyprioritizeeconomicandsocialrecoveryasthecoronaviruspandemiceventuallyrecedes.

Twosimultaneousphenomenaduringthecoronavirusepidemicmakethispointreal.First,asaresultofthespring2020globallock-downsduringthepandemic,theworldexperienced

oneofthebiggestsingledropsinmodernhistoryintheamountofcarbondioxide humans emit.Over the first fewmonths of 2020, global daily CO2emissionsaveragedabout17%lowerthanin2019.Atthemomentsofthemostrestrictiveandextensivelockdowns,emissionsinsomecountrieshov-erednearly30%belowlastyear’saverages....61

Nevertheless,inMay2020,theworldhitarecord418partspermil-lionatmosphericconcentrationofcarbondioxide.Withoutthecoro-navirus-induced drop in emissions, it would have been roughly418.4partspermillion.62Theseeminglyhugedropsinemissionshadonlyasmalleffectonslowing—anddidnotcomeanywhereclosetoreversing—the buildup of atmospheric greenhouse gas concentra-tions.Researchersnowconclude that thesignificantemissionscutsduringCOVID-19meanthattheplanetwillbeonly0.005to0.015°Ccoolerin2030thanitotherwisewouldhavebeenifthepandemichadnotoccurred.63

59. 2018IPCC1.5°CReport,supranote23,at5. 60. 2021IPCCPhysicalScienceReport,supranote12,at17(“Globalsurfacetem-peraturewillcontinuetoincreaseuntilatleastthemid-centuryunderallemissionsscenariosconsidered.Globalwarmingof1.5°Cand2°Cwillbeexceededduring the21stcenturyunlessdeepreductionsinCO2andothergreenhousegasemissionsoccurinthecomingdecades.”). 61. AlejandraBorunda,PlungeinCarbonEmissionsfromLockdownsWillNotSlowClimateChange,NAT’LGEOGRAPHIC(May20,2020),https://www.nationalgeographic.com/science/2020/05/plunge-in-carbon-emissions-lockdowns-will-not-slow-climate-change[https://perma.cc/3TMW-TKUK]. 62. Id. 63. PiersM.Forster,HarrietI.Forster,MatJ.Evans,MatthewJ.Gidden,ChrisD.

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Thus,evenattheheightofcoronavirusrestrictions,wewerestillputtingcarbondioxideintotheatmospherefasterthanitcouldcyclebackout.Asaresult,“eventhoughemissionshavedropped,CO2isstillgoingintotheatmosphereanditwillstillaccumulatethere,justasithassincehumansstartedburningvastamountsoffossilfuels.”64Asonescientistputit,“[t]hebuildupofCO2isabitliketrashinaland-fill....Aswekeepemitting,itkeepspilingup.”65Onlyradicalreduc-tionsinthe“trash”canstopthe“landfill”fromrisingfurther.

Reducingthe“trash”willrequireunprecedentedpolitical,social,economic,andtechnological transformations. IntheIPCC’sanalysis,forexample:

Inmodelpathwayswithnoorlimitedovershootof1.5°C,globalnetanthro-pogenic CO2 emissions [must] decline by about 45% from 2010 levels by2030(40–60%interquartilerange),reachingnetzeroaround2050(2045–2055 interquartile range). For limiting global warming to below 2°C CO2emissionsareprojectedtodeclinebyabout25%by2030inmostpathways(10–30%interquartilerange)andreachnetzeroaround2070(2065–2080interquartilerange).66

Inotherwords,tomakearealdifference,“[e]missionsmustfall7.6percent—in linewiththeworst-case lockdownscenario for2020—everyyearthisdecadetoensurethe1.5Ccap,unlessothermeansarefoundtoremovecarbonfromtheatmosphere ... .”67 Ifpastperfor-manceisanyguide,theworldisunlikelytosustainthesepandemic-drivenemissions cuts,whichwere forallpracticalpurposes forceduponsocieties.68

Jones,ChristophA.Keller,RobinD.Lamboll,CorinneLeQuéré,JoeriRogelj,DeborahRosen,Carl-FriedrichSchleussner,ThomasB.Richardson,ChristopherJ.Smith&Ste-venT.Turnock,CurrentandFutureGlobalClimateImpactsResultingfromCOVID-19,10NATURECLIMATECHANGE913,913(2020). 64. Borunda,supranote61. 65. CO2LevelsReachRecordHigh,WEEK,June26,2020,at19. 66. 2018IPCC1.5°CReport,supranote23,at12. 67. Global CO2 Emissions Could Fall 7 Percent in 2020 due to COVID-19, StudyShows, FRANCE24 (May 20, 2020), https://www.france24.com/en/20200520-co2-emissions-could-fall-7-percent-in-2020-due-to-covid-19-study-shows [https://perma.cc/22FV-GH7E](emphasisadded)(citingCorinneLeQuéré,RobertB.Jackson,MatthewW.Jones,AdamJ.P.Smith,SamAbernethy,RobbieM.Andrew,AnthonyJ.De-Gol,DavidR.Willis,YuliShan,JosepG.Canadell,PierreFriedlingstein,FelixCreutzig&GlenP.Peters,TemporaryReductioninDailyGlobalCO2EmissionsDuringtheCOVID-19ForcedConfinement,10NATURECLIMATECHANGE647(2020)). 68. Newetal.,supranote24,at8–9(summarizingvariouslinesofresearchindi-catingthattheemissionscutsrequiredtostaybelow2°Cofwarmingarevirtuallyim-possible);seealsoPeterChristoff,Introduction:FourDegreesorMore?,inFOURDEGREESOFGLOBALWARMING:AUSTRALIAINAHOTWORLD1(PeterChristoffed.,2014)(“[T]here


InthecontextofthisArticle,itisalsoworthnotingthatachievingthe1.5°Cmitigationgoalrequiressignificantsocietaltransformations,althoughlesserinmagnitudeandcomplexitythanwhatweforeseeasbecomingnecessaryontheadaptationsideat3°Cto4°C.69AstheIPCCexpounded:

Pathways limiting global warming to 1.5°C with no or limited overshootwouldrequirerapidandfar-reachingtransitionsinenergy,land,urbanandinfrastructure (including transport and buildings), and industrial systems(highconfidence).Thesesystemstransitionsareunprecedentedintermsofscale,butnotnecessarilyintermsofspeed,andimplydeepemissionsreduc-tions inall sectors,awideportfolioofmitigationoptionsandasignificantupscalingofinvestmentsinthoseoptions.70Themost critical of these social transitions isweaning energy

productionandconsumptionoffoffossilfuels.71AsthePathwaystoDeep Decarbonization project outlines,72 a three-pronged strategymustbeadoptedforanenergytransitionscenariotosucceedinre-ducinggreenhousegasemissionsatlevelsandintimeframesneededtocontainclimatechangetoa2°Cscenario:“(1)highlyefficientenduseofenergyinbuildings,transportation,andindustry;(2)decarbon-izationofelectricityandotherfuels;and(3)fuelswitchingofendusesto electricity and other low-carbon supplies.”73 These changeswill

iswidespreadagreementthatcurrentmitigationefforts...willleadtoglobalaveragewarmingof4°Cormorefrompre-industrial levelsbytheendofthiscentury ... .”);PeiranR.Liu&AdrianE.Raftery,Country-BasedRateofEmissionsReductionsShouldIncreaseby80%BeyondNationallyDeterminedContributionstoMeetthe2°CTarget,2COMMC’NSEARTH&ENV’T29(2021). 69. SeeFrankW.Geels,BenjaminK.Sovacool,TimSchwanen&SteveSorrell,So-ciotechnicalTransitionsforDeepDecarbonization,357SCIENCE1242,1242–44(2017)(detailingsocietalchangeandpoliciesnecessaryfordeepdecarbonization). 70. 2018IPCC1.5°CReport,supranote23,at15. 71. SeeJohnC.Dernbach,LegalPathwaystoDeepDecarbonization:Postscript,48ENV’TL.REP.10875,10881–84(2018)(providingextensivediscussionsandreferencesonthis theme);MichaelB.Gerrard,LegalPathways foraMassive Increase inUtility-ScaleRenewableGenerationCapacity,47ENV’TL.REP.10591,10592(2017);J.B.Ruhl&JamesSalzman,WhatHappensWhentheGreenNewDealMeetstheOldGreenLaws,44VAND.L.REV.693,701–13(2020). 72. SeeJamesH.Williams,BenjaminHaley,FredrichKahrl,JackMoore,AndrewD.Jones,MargaretS.Torn&HaewonMcJeon,PathwaystoDeepDecarbonizationintheUnited States, INST. SUSTAINABLE DEV. & INT’L RELS. (2014), https://usddpp.org/downloads/2014-technical-report.pdf[https://perma.cc/5FCZ-VPM7]. 73. Id.atxiv;seealsoTHEWHITEHOUSE,UNITEDSTATESMID-CENTURYSTRATEGYFORDEEPDECARBONIZATION7(2016)(aimingto“[t]ransition[]toalow-carbonenergysys-tem,bycuttingenergywaste,decarbonizingtheelectricitysystemanddeployingcleanelectricityand lowcarbon fuels in the transportation,buildings, and industrial sec-tors”) (emphasis omitted). There is growing concern that even these initiatives, if

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requirerapidandmassivenationalinitiatives.Ontheenergyproduc-tionside,forexample,projectionsusinga“highrenewables”referencecaseestimatethatbetween1,350and2,500gigawattsofnewwindandsolarrenewablepower-generatingcapacitywouldneedtocomeonlineintheUnitedStatesbetweentodayand2050tomeetParisAc-cord goals—an amount roughly fifteen to thirty times the presentwind-andsolar-generatingcapacity.74However,thereisnoevidencethatglobalgreenhousegasemission levelshavepeakedandturnedthecorner.75Reportafterreportissuedin2019confirmedthatthereislittletosuggestthatnationsareontracktoachieveemission-reduc-tion goals set through various international and domestic institu-tions.76 Even the most climate-progressive states and cities in theUnitedStatesarefallingbehind.77 achieved,willnotsufficeandthatcarbondioxideremovaltechnologiesmustbedevel-opedtofacilitatenetnegativeemissions.SeeWimCarton,AdeniyiAsiyanbi,SilkeBeck,Holly J.Buck& JensF.Lund,NegativeEmissionsand theLongHistoryofCarbonRe-moval,11WIRESCLIMATECHANGE671,671(2020);AnEquitablePathtoDecarboniza-tion,NATURE,Dec.5,2019,at7;NegativeEmissions:TheChronicComplexityofCarbonCapture,ECONOMIST,Dec.7,2019,at22. 74. SeeTHEWHITEHOUSE,supranote73,at4(estimatinganadditional30GWperyearbetween2016and2035,totaling600GW,andthenanadditional60GWperyearbetween2035and2050,totaling750GW,foranestimatedtotalof1,350additionalGW);WILLIAMSETAL.,supranote72,atvii(estimatinganadditional2,500GW,repre-senting30timesthecurrentcapacity). 75. THEWHITEHOUSE,supranote73,at19. 76. See,e.g.,U.N.ENV’TPROGRAMME,EMISSIONSGAPREPORT2019,atxiv-xv(2019)(noting that global greenhousegas emissions roseonaverage1.5percent annuallyoverthepastdecadeand“[t]hereisnosignofGHGemissionspeakinginthenextfewyears”); ROBERTWATSON, JAMES J.MCCARTHY,PABLOCANZIANI,NEBOJSANAKICENOVIC&LILIANAHISAS,FEU-US,THETRUTHBEHINDTHECLIMATEPLEDGES,ati(2019)(“Ananalysisofcurrentcommitmentstoreduceemissionsbetween2020and2030showsthatal-most75percentoftheclimatepledgesarepartiallyortotallyinsufficienttocontributetoreducingGHGemissionsby50percentby2030,andsomeofthesepledgesareun-likelytobeachieved.”). 77. See Getting Greener: Cost-Effective Options for Achieving New York State’sGreenhouse Gas Goals, CITIZENS BUDGET COMM’N 1–2 (2019), https://cbcny.org/sites/default/files/media/files/REPORT_GettingGreener_120602019.pdf[https://perma.cc/KBT8-TWNP](identifyingobstacles toachievingemissionreduc-tion goals); California Green Innovation Index, NEXT 10, at 4 (2019),https://www.next10.org/sites/default/files/2019-10/2019-california-green-innova-tion-index-final.pdf [https://perma.cc/URM7-VAZB](“California will reach its 2030and2050goalsin2061and2157,respectively–representinga31-yearanda107-yeardelay.”);seealsoSamuelA.Markolf,InesM.L.Azevedo,MarkMuro&DavidG.Vic-tor,PledgesandProgress:StepsTowardGreenhouseGasEmissionsReductionsinthe100LargestCitiesAcrosstheUnitedStates,BROOKINGSINST.3(2020),https://www.brook-ings.edu/wp-content/uploads/2020/10/FP_20201022_ghg_pledges_v4.pdf


Althoughweknowwhat needs to bedone,making the energytransformationandothernecessarysocialchangesneededtowrestleemissionsundercontrolrequiresovercoming“theinterlinkedmixoftechnologies,infrastructures,organizations,markets,regulations,anduser practices that together deliver societal functions.”78 The re-sistancetochangehasbecomeasoberingreality,asestimatesofthemassivetechnologyandsocial transformationcampaignsneededtostabilizeclimatemadeasrecentlyas2004weresoonaftershowntofallsignificantlyshortofwhatwillbeneeded79andthe“stickiness”ofenergypathdependenciesbecomesmoreobvious.80Morerecentpro-posed“roadmaps”todeepdecarbonizationoutlinenolessthanher-culeanpolicyeffortsandtechnologicalbreakthroughs,noneofwhichisyetevenonthehorizon.81Theworld’scontinuinginabilitytotacklethese transformations on themitigation side gives credence to ourconcernsfor4°Cadaptationgovernance.82

[https://perma.cc/QRT2-AXCU](notingthattwo-thirdsofU.S.citiesthathaveadoptedemissions-reductiontargetsarefallingshortofmeetingthem);JeffreyBrainard,NewsinBrief:U.S.CitiesLabortoCutEmissions,370SCIENCE508,509(2020). 78. Geelsetal.,supranote69,at1242. 79. StevenJ.Davis,LongCao,KenCaldeira&MartinI.Hoffert,RethinkingWedges,ENV’TRSCH.LETTERS,Jan.9,2013,at1–2.SeegenerallyEliKintisch,ClimateStudyHigh-lightsWedgeIssue,339SCIENCE128,128–29(2013)(summarizingthestudy). 80. See,e.g.,MelissaPowers,NaturalGasLock-In,69KAN.L.REV.889,941(2021). 81. See,e.g., JohanRockström,OwenGaffney, JoeriRogelj,MalteMeinshausen,NebojsaNakicenovic&HansJoachimSchellnhuber,ARoadmapforRapidDecarboniza-tion, 355 SCIENCE 1269, 1270–71 (2017) (outlining successively aggressive stagesneeded for decarbonization); Lila Warszawski,Elmar Kriegler,Timothy M. Len-ton,Owen Gaffney,Daniela Jacob,Daniel Klingenfeld,Ryu Koide,María MáñezCosta,Dirk Messner,Nebojsa Nakicenovic,Hans Joachim Schellnhuber,PeterSchlosser,KazuhikoTakeuchi,SanderVanDerLeeuw,GailWhiteman&JohanRock-ström,AllOptions,NotSilverBullets,NeededtoLimitGlobalWarmingto1.5°C:ASce-narioAppraisal,ENV’TRSCH.LETTERS,May26,2021,at6(rulingoutmeetingthe1.5°Cwithoutusingmultiplemitigationleversattechnologically“challenging”levels). 82. SeeMartinParry,JasonLowe&ClairHanson,Overshoot,Adapt,andRecover,458NATURE 1102, 1102–03 (2009) (outlining likely scenarios asmitigation fails togaintraction);2021IPCCPhysicalScienceReport,supranote12,at13,SPM-17toSPM-18(accepting3°Castheamountofwarmingmostlikelytooccurby2100,withacon-tinuing“businessasusual”scenarioprojectingevenhigherglobalaverageincreasesof3.3°Cto5.7°Cbytheendofthecentury;andprojectingthattheworldwillexceed1.5°Cforatleastsomedecadesthiscentury;moreover,onlythelowestemissionsscenariohasnochanceofexceeding2°C,whilethethreehighestemissionsscenarioshavenochanceofnotexceeding2°C).

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2. CarbonBudgetsAlsoSuggestthatthe2°CMitigationGoalIsUnrealistic

AtmosphericCO2concentrationsindicatethattheplanetalreadyiscommittedtowarmingthatexceeds2°C,andeventhecoronaviruspandemicwasinsufficienttokeepthoseconcentrationsfromcontin-uingtoincrease.Othermetricstellasimilartale.Forexample,anotherwaytothinkaboutthe1.5°C/2°Cclimatemitigationgoalistoaskhowmuchofacarbonbudgetwehaveleft—thatis,howmuchmoreCO2canweaddtotheatmosphereandstillhaveareasonablechanceofkeepingwarmingtolessthan1.5°Cor2°Cabovepre-industriallevels?TheIPCC,forexample,statedin2018thataccumulatedanthropogeniccarbonemissionsatthatpointwereunlikelysufficienttopushglobalaverage warming past 1.5°C within this century.83 However, thoseemissionsdidnotstop,orreach“netzero,”84in2018,raisingtheissueofhowmuchmoreleewayhumanityhas.

Carbonbudgetestimatesmean little intheabstract:whatdoesonegigatonne(billiontonnes,orGt)reallymeanintermsofhumanactivity?Toputthefollowingdiscussionofestimatesinperspective,in2019globalenergy-relatedemissionsofcarbondioxideflattenedaftertwoyearsofincreasesto33Gt,85butthetotalglobalemissionsstillincreased,reaching36.81Gt.86Asaroughruleofthumb,theIPCCestimatestotalglobalCO2emissionstobe42Gtperyear,giveortake3Gt(39–45Gtperyear).87

Evenwithintheuncertainandprobability-basedworldofclimatechangeprojections,carbonbudgetsdeserveaplaceofhonorforlackofcertaintyandvariability.Asaresult,thefollowingdiscussionseeksto “ballpark” best-case andworst-case estimates. Nevertheless, thebottomlineisclear:abusiness-as-usualworldwilleatupeventhe2°Ccarbonbudgetwithinafewdecades.

83. 2018IPCC1.5°CReport,supranote23,at5. 84. 2021 IPCC Physical Science Report, supra note 12, at SPM-36 (“Each 1000GtCO2ofcumulativeCO2emissions isassessedto likelycausea0.27°Cto0.63°Cin-creaseinglobalsurfacetemperaturewithabestestimateof0.45°C.”). 85. Global CO2 Emissions in 2019, INT’L. ENERGY AGENCY (Feb. 11, 2020),https://www.iea.org/articles/global-co2-emissions-in-2019 [https://perma.cc/JE9F-KZPA]. 86. ZekeHausfather,Analysis:GlobalFossil-FuelEmissionsup0.6%in2019DuetoChina, CARBON BRIEF (Dec. 4, 2019), https://www.carbonbrief.org/analysis-global-fossil-fuel-emissions-up-zero-point-six-per-cent-in-2019-due-to-china [https://perma.cc/M9HS-RC5G]. 87. 2018IPCC1.5°CReport,supranote23,at12.


AccordingtotheIPCCin2021,humanityhademitted2,390GtCO2between1850and2019,giveortake240Gt.88 Itestimatedthat, tohaveatwo-thirdschance(meaningoddsthataretwiceasbadasinRussianRoulette)ofstayingwithin1.5°Cor2.0°Cofglobalaveragewarming,humanityhad400or1,150Gt, respectively,ofCO2 emis-sionsleft—ever.89Toincreasethechancesto83percent,theremain-ingcarbonbudgetsdropto300or900Gt,respectively.90Ifhumanitycontinuestoemitaround40Gtperyear,itwilluseupthehigher-oddsbudgetfor1.5°Csometimein2027andthehigher-oddsbudgetfor2°Csometimein2043.

Nevertheless,individualcarbon-budgetstudiesexhibitconsider-ablevariation.Between2016and2018,expertsproducedninediffer-entstudiestryingtocalculatehumanity’sremainingcarbonbudgettokeepglobalaveragetemperatureincreasesbelow1.5°C.Assessmentsoftheseninestudiesconcludedthat“theremainingcarbonbudgettolimitwarmingto‘wellbelow’1.5°Cmighthavealreadybeenexceededbyemissionsto-date,ormightbeaslargeas15moreyearsofemis-sionsatourcurrentrate.”91Inshort,atbestthebudgetisusedupby2033.Evenifaslimbudgetremains,however,theCO2emissionscom-mitted from existing fossil-fuel power plants and those currentlyplanned, permitted, and under construction (which are mostly inChinaand India)will aloneconsume theentireCO2budget that re-mains to limit warming to 1.5°C.92 Worse still, another study

88. 2021IPCCPhysicalScienceReport,supranote12,atSPM-38. 89. Id.atSPM-38,tbl.SPM.2. 90. Id. 91. ZekeHausfather,Analysis:HowMuchCarbonBudget’IsLefttoLimitWarmingto 1.5C?, CARBONBRIEF (April 9, 2018), https://www.carbonbrief.org/analysis-how-much-carbon-budget-is-left-to-limit-global-warming-to-1-5c [https://perma.cc/VR6G-YJQZ]. 92. Dan Tong, Qiang Zhang, Yixuan Zheng, Ken Caldeira, Christine Shearer,ChaopengHong,YueQin&StevenJ.Davis,CommittedEmissionsfromExistingEnergyInfrastructure Jeopardize 1.5°CClimateTarget, 572NATURE 373, 373 (2019). China,whichaccountsfor28%ofglobalemissions,reliesoncoalfor58%ofitsenergycon-sumptionand66%ofitselectricpowergeneration,andhasatleast100gigawattsofcoalgenerationcapacityunderconstruction,announcedin2020thatitwouldreachzeronetemissionsbefore2060,butmanyexpertswereskepticalitcouldmakesuchaU-turn.SeeDennisNormile,China’sBoldClimatePledgeEarnsPraise—ButIsitFeasi-ble?,370SCIENCE17,17–18(2020)(reportingthat432minesworldwide,mostly inAsiaandmanyofwhicharepubliclyfinanced,areplannedtoopenorexpandtopro-duce2.5billiontonsofnewminingcapacityby2030).Over70%ofthenewcapacitywouldproduce thermalcoalused for fuelingpowerplants.SeeRYANDRISKELLTATE,CHRISTINESHEARER&ANDISWAMATIKINCA,DEEPTROUBLE:TRACKINGGLOBALCOALMINEPROPOSALS4(2021).

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concluded that even if all fossil fuel emissions were immediatelyhalted, “current trends in global food systems would prevent theachievement of the 1.5°C target and, by the end of the century,threaten the achievement of the 2.0°C target.”93 Thus, business-as-usualinenergyandfoodalonecoulddoublyblowpastthe2.0°Cmiti-gationtarget.

Tocomplicatemattersstillfurther,theforegoingcarbon-budgetanalysesare limited toanthropogenic emissions,whicharenot theonlysourceofgreenhousegasses.Asclimatechangeforcesecologicalsystemsacrossnonlinearthresholdsoftransformation(discussedinPartII),historicallysequesteredgreenhousegaseswillbereleased.AsscientistsreportedinNatureinlate2019:

Theworld’sremainingemissionsbudgetfora50:50chanceofstayingwithin1.5 °Cofwarmingisonlyabout500 gigatonnes(Gt)ofCO2.Permafrostemis-sionscould takeanestimated20%(100 Gt CO2)off thisbudget,and that’swithout includingmethane fromdeeppermafrostorunderseahydrates. Ifforests are close to tipping points, Amazon dieback could release another90 Gt CO2andborealforestsafurther110 Gt CO2.WithglobaltotalCO2emis-sionsstillatmorethan40 Gt peryear,theremainingbudgetcouldbeallbuterasedalready.94

Thisecologicalcontributiontoclimatechangeonlygetsworseaswemove past 2°C, as “huge swaths of theworld’s tropical forestswillbegintolosemorecarbonthantheyaccumulate.Already,thehottestforestsinSouthAmericahavereachedthatpoint.”95Inaddition,Arcticlakes have been observed releasing large bubbles of methane—enough to fuel pillars of flame over the water’s surface when setalight—sinceatleast2018.96Theselakes,lookingeerilyliketheMac-Beth witches’ bubbling cauldron,may be the first signs that Arcticfeedbackloopsarenowinmotion,acceleratinggreenhousegasemis-sions, climate change, and any chance of stayingwithin the carbonbudget foreven2°C.97 In theArcticOcean itself,newresearch indi-catesthatlunarandtidalcyclesplayimportantrolesinmethanegasrelease,leadingtounderestimatesofhowmuchofthisgreenhousegas 93. MichaelA.Clark,NinaG.G.Domingo,KimerlyColgan,SumilK.Thakrar,DavidTilman,JohnLynch,InêsL.Azevedo&JasonD.Hill,GlobalFoodSystemEmissionsCouldPrecludeAchievingthe1.5°Cand2°CClimateChangeTargets,370SCIENCE705,705–08(2020). 94. Lentonetal.,supranote7,at594(citationsomitted). 95. Elizabeth Pennisi,Tropical Forests Store CarbonDespiteWarming, 368 SCI-ENCE.813,813(2020). 96. ChrisMooney,Arctic Cauldron,WASH.POST (Sept. 22, 2018), https://www.washingtonpost.com/graphics/2018/national/arctic-lakes-are-bubbling-and-hissing-with-dangerous-greenhouse-gases[https://perma.cc/D8JY-E8YY]. 97. Id.


theArcticiscurrentlyemitting.98Lookingmorebroadlythanjustdi-recthuman-generatedemissions,therefore,weprobablyhavealreadyconsumedthe2°Cbudgetregardlessofwhetheranthropogenicemis-sionsarecontrolled.

C. WHEREAREWEGOING?COMMITTEDWARMINGANDPROJECTIONSFORGLOBALAVERAGETEMPERATURES

Predictingfutureincreasesinglobalaveragetemperaturebyne-cessityrequiresmakingeducatedguessesabouthowavarietyofvar-iables,bothhumanandplanetary,willactuallyplayoutinthefuture.Thesevariablesincludetherateatwhichandextenttowhichtheen-ergysystemisdecarbonized(thatis,theconversiontorenewableandnuclearpower),humanpopulationgrowth,patternsofconsumerism,whenandtowhatextenttheocean’scapacitytoabsorbcarbondiox-idewillsloworstop,theextenttowhichmeltingicewillacceleratewarmingbyexposingdarksurfaces,andmanymore.Thevarietyofguessesthatclimatemodelersmakegoesalongwaytoexplainingthevarietyofpredictionsthatexistabouthowwarmtheplanetwillbe-come—and how fast. Nevertheless, most scenarios agree that theplanetiswellonitswaytoa4°Cincreaseinglobalaveragetempera-ture,whichcouldoccurassoonasfiftyyearsfromnow.

TheIPCC,forexample,mostconsistentlycomparesfourscenar-ios.99 Itsbusiness-as-usualscenarios tendtosuggest that theworldcouldreach4°Cbytheendofthiscentury.100In2017,researchersus-ing a different methodology published their projections inNature,

98. Nabil Sultan, Andreia Plaza-Faverola, Sunil Vadakkepuliyambatta,StefanBuenz&JochenKnies,ImpactofTidesandSea-LevelonDeep-SeaArcticMethaneEmis-sions,NATURECOMMC’NS,Oct.9,2020,at1–2. 99. 2019IPCCSynthesisReport,supranote17,at8. 100. Id.at9fig.SPM5(a),12fig.SPM7;seealsoNewetal.,supranote24,at9–10(“Allbuttwoofthemodels[inaseriesofmodelruns]reach4°Cbeforetheendofthetwenty-firstcentury,withthemostsensitivemodelreaching4°Cby2061,awarmingrateof0.5°Cperdecade.Allthemodelswarmby2°Cbetween2045and2060.Thissupportsthemessagethatanearlypeakanddeparturefromabusiness-as-usualemis-sionspathwayareessentialifamaximumtemperaturebelow4°Cistobeavoidedwithanydegreeofcertainty.”);Christoff,supranote68(“[T]hereiswidespreadagreementthatcurrentmitigationefforts...willleadtoglobalaveragewarmingof4°Cormorefrompre-industriallevelsbytheendofthiscentury.”);2021IPCCPhysicalScienceRe-port,supranote12,atSPM-17toSPM-18,tbl.SPM.1(indicatingthatunderabusiness-as-usualscenario,globalaveragetemperaturecouldincreaseasmuchas5.7°Cbytheendofthecentury).

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concludingthatby2100“[t]helikelyrangeofglobaltemperaturein-creaseis2.0-4.9°C,withamedianof3.2°C....”101

Thebreadthofthatrangeisattributabletouncertaintyregardinghowfastandhowmuchourclimaterespondstochanges inatmos-pheric greenhouse gas concentrations—known as climate sensitiv-ity.102Thebenchmarkforassessmentistheexpectedrangeofincreaseintemperatureat560ppm,whichisdoublethepre-industrialconcen-trationandroughly145ppmabove thecurrent level.103Oneof thefirstassessments,a1979studybytheNationalResearchCouncil,pro-ducedabroadrangeof1.5℃to4.5°C.104Recenteffortstotightentherangedonotbodewell.Themostcomprehensivestudy,publishedin2019,weavestogethercontemporarywarmingtrends,thelatestun-derstanding of climate system feedback loops and other dynamics,and studies of ancient climates.105 The study concludes that at 560ppm the likely (66% chance)warming range is between2.6°C and3.9°C.106Thestudywasunabletoruleoutthatthesensitivitycouldbeabove4.5°Cperdoublingofcarbondioxidelevels,althoughthisisnotlikely.107 In other words, barring rapid global political, social, andtechnological transformations of the breadth and depth discussedabove,wewillbefortunatetolimittemperatureincreaseto2.6℃,justaslikelytoreach3.9℃,andthepossibilityofreaching4.0℃orhighercannotbeignored.

InMay2020,“theconcentrationofcarbondioxideintheatmos-pherecreptuptoabout418partspermillion.Itwasthehighesteverrecordedinhumanhistoryandlikelyhigherthanatanypointinthe

101. AdrianE.Raftery,AlecZimmer,DarganM.W.Frierson,RichardStartz&Pei-ranLiu,Lessthan2°CWarmingby2100Unlikely,7NATURECLIMATECHANGE637,639(2017). 102. S.C.Sherwood,M.J.Webb,J.D.Annan,K.C.Armour,P.M.Forster,J.C.Har-greaves,G.Hegerl,S.A.Klein,K.D.Marvel,E.J.Rohling,M.Watanabe,T.Andrews,P.Braconnot,C.S.Bretherton,G.L.Foster,Z.Hausfather,A.S.vonderHeydt,R.Knutti,T.Mauritsen,J.R.Norris,C.Proistosescu,M.Rugenstein,G.A.Schmidt,K.B.Tokarska&M.D.Zelinka,AnAssessmentofEarth’sClimateSensitivityUsingMultipleLinesofEvi-dence,REVS.GEOPHYSICS,July22,2020,at2. 103. Id. 104. Id. 105. Id.at1;seealsoPaulVoosen,Earth’sClimateDestinyFinallySeenMoreClearly,369SCIENCE354,354–55(2020)(summarizingthestudy). 106. Sherwoodetal.,supranote102,at1. 107. Id. (debating over the upper bounds of climate sensitivity); see also PaulVoosen,NewClimateModelsForecastaWarmingSurge,364SCIENCE222(2019)(dis-cussingdebateoverrecentmodelsshowingwarmingrisingto5°C).


lastthreemillionyears.”108Truetothe“trashpile”metaphor,109evenafter another year of pandemic conditions theMay 2021measure-mentbrokethatrecord,cominginatjustover419ppm.110AccordingtotheNationalOceanicandAtmosphericAdministration(NOAA),thelast time carbondioxide concentrationswereover400ppm (threemillionyearsago),“temperaturewas2°–3°C(3.6°–5.4°F)higherthanduringthepre-industrialera,andsealevelwas15–25meters(50–80feet)higherthantoday.”111Giventhedelaysinvolvedinatmosphericdynamics,humansthusprobablyhavealreadycommittedtheplanettoafuturethatblowsrightbythe2°Cwarminggoal.

Theincreasingconcentrationofcarbondioxidealreadyaccumu-latedintheatmosphere—theplanet’sresponsetowhichconstitutesanimportantsourceofuncertaintyregardinghowfasttheplanetwillwarm—represents“committedwarming,”afutureofglobalaveragetemperatureincreasesevenifallnewemissionsceasetomorrow(un-lesstechnologyisdevelopedtoactivelydrawCO2backoutoftheat-mosphereonamassivescale).Moreover,formorethanadecadenow,theCO2concentrationintheatmospherehasbeenincreasingroughly2.3ppmperyear.112Atthatrate,theconcentrationwillberoughly485ppmby2050andat thedoubling thresholdof560ppmbyaround2080.Fromthere,by2100the2.0°Cmitigationtargetwillbeahistor-icalfootnote.Importantlyforadaptationgovernance,however,warm-ingdoesn’tstopin2100,noris560ppmanaturallyimposedceilingongreenhousegasconcentrations;asaresult,adaptationgovernancemust itselfbecontinuallyadaptable,at leastuntilbothatmosphericgreenhousegasconcentrationsandtheresultingchangestoEarth’ssystemsstabilize.

108. Borunda,supranote61. 109. SeeCO2LevelsReachRecordHigh,supranote65. 110. CarbonDioxidePeaksNear420PartsPerMillionatMaunaLoaObservatory,NOAA RSCH NEWS (June 7, 2021), https://research.noaa.gov/article/ArtMID/587/ArticleID/2764/Coronavirus-response-barely-slows-rising-carbon-dioxide [https://perma.cc/B3NF-WXCZ]. 111. Lindsey,supranote12. 112. Id.

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II.ANTICIPATING4°C:WHATDOESTHEWORLDLOOKLIKEBEYOND2°C?

Climatechangeis,well,change—anexpressionofalltheaccumu-latedextraenergy(mostlyintheformofheat)workingontheplanet’svariousphysical,chemical,andbiologicalsystemsatallscalessimul-taneously.EnvisioninggovernanceoftheUnitedStatesat4°Crequirespolicy-makersandadaptationplannerstoimaginenotafuturestablestateofbeinginahotterworldbutratheracontinualandacceleratingprocessofdiscontinuousandoftenunpredictabletransformation.In-deed,evenleavingthecoronaviruspandemictothesideforthemo-ment,Americansarealreadyexperiencinganacceleratingpaceofnat-uraldisastersandextremeinconveniences,lurchingfromwildfirestohurricanestodroughtto“PolarVortex”winterstosevereflooding.113Speciesarealreadymigratingpolewardandhigherinaltitude(terres-trial)ordeeperindepth(marine),whichisrearrangingecosystems,perturbing food webs (including humans’), and changing fisheriesworldwide,amongotherdisruptionstonaturalsystemsuponwhichhumansdepend.114

Theseexperienceswillonlygetworse,challengingtheabilitiesofgovernance institutions to provide—or perhaps even define—thesenseofstabilitynecessary forsocial-ecologicalsystemstoproduc-tivelyadapttotheirnewreality.Topaintamorevividpictureofthatchallenge, in this section we summarize the scientific evidence of 113. SeeBillMcKibben,HowFastIstheClimateChanging?:It’saNewWorld,Eachand Every Day, NEW YORKER (Sept. 3, 2020), https://www.newyorker.com/news/annals-of-a-warming-planet/how-fast-is-the-climate-changing-its-a-new-world-each-and-every-day[https://perma.cc/JJ8M-LHJX](describingthewildfireandhurricanecombinationsinlateAugustandearlySeptember2020);KellyLevin,ClimateChange,FrigidTemperaturesandthePolarVortex:3ThingstoKnow,WORLDRES.INST.(Jan.30,2019), wri.org/insights/climate-change-frigid-temperatures-and-polar-vortex-3-things-know [https://perma.cc/G8LY-V393] (describing the relationship betweenclimatechangeandPolarVortex). 114. SeeStevenL.Chown,MarineFoodWebsDestabilized,369SCIENCE770,770–71(2020)(discussingacollectionofresearchstudiesonthistheme);JayR.Malcolm,AdamMarkham,RonaldP.Neilson&MichaelGaraci,EstimatedMigrationRatesUnderScenarios of Global Climate Change, 29 J. BIOGEOGRAPHY 835, 836, 838–42 (2002);ChristyM.McCain,SarahR.B.King&TimM.Szewczyk,UnusuallyLargeUpwardShiftsinCold-Adapted,MontaneMammalsasTemperatureWarms,ECOLOGY,Apr.2021,at1;MartenScheffer,SteveCarpenter,JonathanA.Foley,CarlFolke&BrianWalker,Cata-strophicShiftsinEcosystems,413NATURE591,591–96(2001);BrettR.Scheffers,LucDeMeester,TomC.L.Bridge,AryA.Hoffmann,JohnM.Pandolfi,RichardT.Corlett,StuartH.M.Butchart,PaulPearce-Kelly,KitM.Kovacs,DavidDudgeon,MichelaPaci-fici,CarloRondinini,WendyB.Foden,TaraG.Martin,CamiloMora,DavidBickford&JamesE.M.Watson,TheBroadFootprintofClimateChangefromGenestoBiomestoPeople,354SCIENCE719,719–20(2016).


loomingnonlinearchangetotheplanetandthelimitsofhumanadap-tivecapacity,thenusethatbackgroundtoenvisionconditionsintheUnitedStatesundera4°Cscenario.

A. COMINGTOGRIPSWITHNONLINEARCHANGEThe tendencyamongnonscientistswhen thinkingaboutglobal

warmingistothinkinlinearterms:ifXamountofdamageoccurswith1°Cofwarming,then2Xdamagewilloccurat2°Cofwarming,3Xat3°C,andsoon.Thatwouldbebadenough,butafundamentaltruthaboutarapidlywarmingplanetisthattheimpactsfromasteadilyin-creasingmeanglobalaveragetemperaturearenonlinear,andintwosenses.First,theamountofchangeoccurringisoftengeometric,witheachincrementofwarmingmultiplyingandaccelerating,ratherthansimply adding, impacts. Second, at somepoint the changesbecometransformative,fundamentallyalteringsocial-ecologicalsystemsintonewstatesofbeing.115Tomakemattersevenmorechaotic,differentsystems transform at different temperatures. Some, like Arctic andcoralreefsocial-ecologicalsystems,arealreadytransforming.116Oth-ers, likemangrove social-ecological systems, currently face far lessrisk.117Nevertheless,itdoesnottakemuch—thedeclineofatop-levelpredatorbecauseoftemperatureortheexpansionofanotherpreda-tor’s range—to throw ecological systems into cascade transfor-mations.118

Thus,astheIPCChasemphasized,eventhedifferencebetween1.5°C and 2°C is importantwhen thinking about future adaptation

115. SeeSmithetal.,supranote35(discussingadaptingto4°Cwillbeamoresub-stantial,continuous,andtransformativeprocess). 116. See2018IPCC1.5°CReport,supranote23,at11fig.SPM.2;seealsoRobinE.Bell&HeleneSeroussi,History,MassLoss,Structure,andDynamicBehavioroftheAnt-arcticIceSheet,367SCIENCE1321,1321–25(2020)(discussingtheaverageairtem-peratureontheAntarcticPeninsulabetween1950and2000,andAntarcticcontribu-tiontoSLRsince1992,whichwillaccelerateiftemperatureskeeprising);Lentonetal.,supranote7,at593(discussingtheevidencethattheGreenlandicesheetisexpe-riencingmasslossatacceleratingratesandhasswitchedtoanewdynamicstateofsustainedmassloss). 117. 2018IPCC1.5°CReport,supranote23,at11fig.SPM.2. 118. SeeElizabethPennisi,AnEcosystemGoesTopsy-TurveyasaTinyFishTakesOver,369SCIENCE1154,1154–55(2020);DouglasB.Rasher,RobertS.Steneck,JochenHalfar,KristyJ.Kroeker,JustinB.Ries,M.TimTinker,PhoebeT.W.Chan,JanFietzke,NicholasA.Kamenos,BrendaH.Konar,JonathanS.Lefcheck,ChristopherJ.D.Norley,BenjaminP.Weitzman,IsaacT.Westfield&JamesA.Estes,KeystonePredatorsGovernthePathwayandPaceofImpactsinaSubarcticMarineEcosystem,369SCIENCE1351,1351–54(2020).

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governance.119 For example, in some locations, the 0.5°C change inglobalaveragetemperaturefrom1.5°Cto2°Cmakesthehottestdaysafull1°Chotterandthehottestnights1.5°Chotter120—anexampleofgeometricimpacts.121HalfadegreeCelsiusalsomakesadramaticdif-ferencetotheArctic:“With1.5°Cofglobalwarming,oneseaice-freeArcticsummerisprojectedpercentury.Thislikelihoodisincreasedtoatleastoneperdecadewith2°Cglobalwarming.”122Here,a0.5°Cdif-ferenceintheincreaseinglobalaveragetemperatureleadstoaten-foldincreaseinimpacts.Similarly,asglobalaveragetemperaturein-creasesarithmetically,ageometricallyacceleratingpercentageofspe-ciesareaffected: “Of105,000species studied,6%of insects,8%ofplantsand4%ofvertebratesareprojectedtoloseoverhalfoftheirclimaticallydeterminedgeographicrangeforglobalwarmingof1.5°C,comparedwith18%ofinsects,16%ofplantsand8%ofvertebratesforglobalwarmingof2°C(mediumconfidence).”123

Thesenonlineartrajectoriescontinuepast2°C,makingaworldat4°Cone inwhich the risksassociatedwithnaturaldisastersandecologicalfailureareglobalinscopeandunimaginablyintensecom-paredtothepresent.Forexample,arecentcomprehensivestudyofthirtydifferentimpactsofclimatechangeconcludedthat

theglobalaveragechanceofamajorheatwaveincreasesfrom5%in1981–2010to28%at1.5°Cand92%at4°C,ofanagriculturaldroughtincreasesfrom9to24%at1.5°Cand61%at4°C,andofthe50-yearreturnperiodriverflood increases from2 to 2.4%at 1.5°C and5.4%at 4°C. The chance of a

119. 2018IPCC1.5°CReport,supranote23,at7;seealso2021IPCCPhysicalScienceReport,supranote12,atSPM-19(“Witheveryadditionalincrementofglobalwarming,changesinextremescontinuetobecomelarger.”),SPM-32(“Withfurtherglobalwarm-ing, every region is projected to increasingly experience concurrent and multiplechangesinclimaticimpact-drivers.Changesinseveralclimaticimpact-driverswouldbemorewidespreadat2°Ccomparedto1.5°Cglobalwarmingandevenmorewide-spreadand/orpronouncedforhigherwarminglevels.”). 120. See2018IPCC1.5°CReport,supranote23,at7(“Extremehotdays inmid-latitudeswarmbyuptoabout3°Catglobalwarmingof1.5°Candabout4°Cat2°C,andextremecoldnightsinhighlatitudeswarmbyuptoabout4.5°Cat1.5°Candabout6°Cat2°C.”). 121. SeealsoNewetal.,supranote24,at10(“Thebroadlyconstantratiooflocalclimatechangetoglobaltemperaturechangeimpliesthattheselocalchangesaream-plifiedina4°Cworld;forexample,alocalchangeof3°Cina+2°Cworld(1°Cgreaterthantheglobalaverage)becomes7.5°Cina+4°Cworld(3.5°Cabovetheglobalaver-age).”). 122. 2018IPCC1.5°CReport,supranote23,at8. 123. Id.


damaging hot spell formaize increases from 5 to 50% at 4°C, whilst thechanceforricerisesfrom27to46%.124

Theseincreasingrisksare,obviously,likelytobecostlytohumanlifeandtoeconomies.Whilenotattheheartofwheretheworstdamagewilloccur, theUnitedStates isbynomeansoutofharm’sway,andprojectionssuggestthatclimatechangewillsubjectittosubstantialhitstoeconomicactivityandsurgesinmortality.125Forallpracticalpurposes,whenmakingplansandpolicyinsuchanenvironment,onewillneedtoassumethatdebilitatingheatwaves,drought,cropfailure,floods,andotherharmsarethenewnormal.126

Animportantreasonwhyconditionsgetsomuchworsebeyond2°Cisthatmoreandmorebiophysicalsystemsbegincrossingtippingpointsastemperatureskeeprising.127Manyecosystemsarealreadycrossingtransformationaltippingpointthresholdsat1.0°Cofwarm-ing,128butthenumberofthosesystemsundergoingtransformationsacceleratesby2°Candcontinuestoexpandfromthere:

Approximately4%(interquartilerange2–7%)oftheglobalterrestriallandareaisprojectedtoundergoatransformationofecosystemsfromonetypetoanotherat1°Cofglobalwarming,comparedwith13%(interquartilerange8–20%)at2°C(mediumconfidence).Thisindicatesthattheareaatriskis

124. N.W.Arnell,J.A.Lowe,A.J.Challinor&T.J.Osborn,GlobalandRegionalIm-pactsofClimateChangeatDifferentLevelsofGlobalTemperatureIncrease,155CLIMATICCHANGE377,377(2019). 125. SeeSolomonHsiang,RobertKopp,AmirJina,JamesRising,MichaelDelgado,ShashankMohan,D.J.Rasmussen,RobertMuir-Wood,PaulWilson,MichaelOppenhei-mer,KateLarsen&TrevorHouser,EstimatingEconomicDamagefromClimateChangein theUnitedStates,356SCIENCE1362,1364–65(2017)(suggesting thatabove1°C,therewillbe lossesof1.2percentUSGDPper1°Cofwarming,andmortality is thelargestincrementalfactorabove2.5°C);seealsoWilliamA.Pizer,What’stheDamagefromClimateChange?,356SCIENCE1330,1330–31(2017)(estimatingthat3°Cleadstoalossof2%ofU.S.GDP,and6°Cis6%loss). 126. SeeTobyR.Ault,OntheEssentialsofDroughtinaChangingClimate,368SCI-ENCE256,256–60(2020)(introducinganin-depth,accessibleexplanationofhowris-ingtemperaturesleadinevitablytomoreintense,frequent,andlong-lastingdroughts). 127. SeeNewetal.,supranote24,at10–11(“Therearearangeofotherpotentialthresholds intheclimatesystemandlargeecosystemsthatmightbecrossedastheworldwarmsfrom2°Cto4°Candbeyond.Theseincludepermanentabsenceofsum-merseaiceintheArctic,lossofthelargeproportionofreef-buildingtropicalcorals,melting of permafrost at rates that result in positive feedbacks to greenhouse gaswarmingthroughCH4andCO2releasesanddie-backoftheAmazonforest.Whilethelocationsofthesethresholdsarenotpreciselydefined,itisclearthattheriskofthesetransitionsoccurringismuchlargerat4°C—andsothenatureofthechangesincli-mateweexperiencemaywellstartshiftingfromincrementaltotransformative.”). 128. SeeLentonetal.,supranote7,at592.

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projectedtobeapproximately50%lowerat1.5°Ccomparedto2°C(mediumconfidence).129

Onewaytolookattheseestimatesisthatthenumberofecosystemstransformingapproximatelytripleswitheach1°Cofwarming.Ifthatrelationshipholds,thenat3°Cabout39%ofecosystemswillbetrans-forming,andsomewherebefore4°Cofwarmingallofthemwillbe.130

Wearewellonthewaythere.Pervasiveshiftsinforestvegetationarealreadyoccurringandarelikelytoaccelerateunderfutureglobalchanges.131Mostatriskaretropicalforests,whicharealreadyexhib-itingnonlinear,unpredictabletrajectoriesofchangeinstructureanddiversity.132 Diverse terrestrial and marine species are exhibitingpolewardrangeextensionsandchanges inabundanceanddistribu-tion.133Risingcarbonreducesthenutrientsinplants,whichisalreadydwindlingterrestrialinsectpopulations.134Allherbivoresareatriskifthistrendcontinues.135Inmanysystems,nonlineareffectsacceler-ate the pace of transformation.136 Projections suggest that shifts in

129. 2018IPCC1.5°CReport,supranote23,at8. 130. SeeHelmutHillebrand,IanDonohue,W.StanleyHarpole,DorotheeHodapp,MichalKucera,AleksandraM.Lewandowska,JulianMerder,JoseM.Montoya&JanA.Freund,ThresholdsforEcologicalResponsestoGlobalChangeDoNotEmergefromEm-piricalData,4NATUREECOLOGY&EVOLUTION1502,1502–09(2020)(discussing thatpreciseprojectionsofwhichsystemscrossthresholdsatwhichtemperatureregimeshaveprovenelusive,thereforesuggestingthatpolicyshouldnotassumethereare“safeoperatingspaces”belowspecifiedlevelsoftemperaturerise). 131. SeeNateG.McDowell,CraigD.Allen,KristinaAnderson-Teixeira,BrianH.Au-kema,BenBond-Lamberty,LouiseChini,JamesS.Clark,MichaelDietze,CharlotteGros-siord, AdamHanbury-Brown,George C.Hurtt, RobertB. Jackson,Daniel J. Johnson,LaraKueppers,JeremyW.Lichstein,KionaOgle,BenjaminPoulter,ThomasA.M.Pugh,RupertSeidl,MonicaG.Turner,MariaUriarte,AnthonyP.Walker&ChonggangXu,PervasiveShiftsinForestDynamicsinaChangingWorld,SCIENCE,May29,2020,at1–3. 132. SeeHaraldBugmann,TreeDiversityReducedtotheBareEssentials:TropicalForestDynamicsCanBeExplainedbyMerelyTwoFunctionalTraitAxes,368SCIENCE128,128–29(2020). 133. See,e.g.,CamilleParmesan,NilsRyrholm,ConstantíStefanescu,JaneK.Hill,ChrisD.Thomas,HenriDescimon,BrianHuntley,LauriKaila,JaakkoKullberg,ToomasTammaru,W. JohnTennent, JeremyA.Thomas&MartinWarren,PolewardShifts inGeographicalRangesofButterflySpeciesAssociatedwithRegionalWarming,399NA-TURE579,579–83(1999)(suggestingthatthiseffecthasbeendocumentedsincethelate1990s). 134. SeeElizabeth Pennisi,Carbon Dioxide IncreaseMay Promote ‘Insect Apoca-lypse’:StudyLinksLow-NutrientPlants toFewerGrasshoppers,368SCIENCE459,459(2020). 135. Seeid. 136. SeeEricSanford,JacquelineL.Sones,MarisolGarcía-Reyes,JeffreyH.R.God-dard& JohnL.Largier,WidespreadShifts in theCoastalBiotaofNorthernCaliforniaDuringthe2014–2016MarineHeatwaves,SCI.REPS.,Mar.12,2019,at6–12.


Earthecosystemsarelikelytooccurover“human”timescalesofyearsand decades,meaning that the collapse of large vulnerable ecosys-tems,suchastheAmazonrainforestandCaribbeancoralreefs,maytakeonlyafewdecadesoncetriggered.137

Althoughothersystemswilltakelongertotransform,oncetheycrossthresholdsofnonlinearchange,thetransformationwill forallpracticalpurposesbeirreversible.138Forexample,underasustainedwarming scenario, a threshold for the integrity of theAntarctic iceshelves,andthusofthestabilityoftheicesheet,seemstoliebetween1.5°Cand2°C.139 Crossing these thresholds implies commitment tolargeice-sheetchangesandsea-levelrisethatmaytakethousandsofyears to be fully realized and may be irreversible on longer timescales.140SimilarconcernsarecomingfromresearchonArcticice141andonoceancirculationsystems.142RecentresearchshowsthattheAtlantic Meridional Overturning Circulation, one of Earth’s majoroceancirculationsystemsresponsibleforplanetaryheatredistribu-tionandknown tobe subject tohistoricalnonlinear shifts, is at itsweakestinthelastmillennium.143Crossinganyoftheseandsimilar

137. SeeGregoryS.Cooper,SimonWillcock&JohnA.Dearing,RegimeShiftsOccurDisproportionatelyFasterinLargerEcosystems,11NATURECOMMC’NS,Mar.10,2020,at7. 138. SeeLentonetal.,supranote7,at592(discussingthatpassingtippingpointswouldpotentiallycommittheworldtolong-termirreversiblechanges). 139. SeeFrankPattyn&MathieuMorlighem,TheUncertainFutureoftheAntarcticIce-Sheet,367SCIENCE1331,1331–35(2020). 140. Seeid.;seealsoJasonP.Briner,JoshuaK.Cuzzone,JessicaA.Badgeley,NicolásE.Young,EricJ.Steig,MathieuMorlighem,Nicole-JeanneSchlegel,GregoryJ.Hakim,JoergM.Schaefer,JesseV.Johnson,AliaJ.Lesnek,ElizabethK.Thomas,EstelleAllan,OleBennike,AllisonA.Cluett,BeataCsatho,AnnedeVernal,JacobDowns,EricLarour&SophieNowicki,RateofMassLossfromtheGreenlandIce-SheetWillExceedHoloceneValuesthisCentury,586NATURE70,70–74(2020);IanJoughin,RichardB.Alley&Da-vidM. Holland, Ice-Sheet Response to Oceanic Forcing, 338 SCIENCE 1172, 1172–76(2012);DirkNotz,TheFutureofIceSheetsandSeaIce:BetweenReversibleRetreatandUnstoppableLoss,106PROC.NAT.ACAD.SCI.20590,20590–95(2009). 141. See I. Eisenman& J.S.Wettlaufer,NonlinearThresholdBehaviorDuring theLossofArticSeaIce,106PROC.NAT.ACAD.SCI.28,28–32(2009)(describingathresholdofArcticicelossthatleadstopermanentyear-roundice-freeconditions). 142. See Thomas F. Stocker, Surprises for Climate Stability, 367 SCIENCE 1425,1425–26(2020). 143. SeeNiklasBoers,Observational-basedEarly-warningSignalsforaCollapseoftheAtlanticMeridionalOverturningCirculation,11NATURECLIMATECHANGE680,680(2021);L.Caesar,G.D.McCarthy ,D.J.R.Thornalley ,N.Cahill&S.Rahmstorf,CurrentAtlanticMeridionalOverturningCirculationWeakestinLastMillennium,14NATUREGE-OSCIENCE118,118–20(2021).

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planetarymega-thresholdsamplifiesthepotentialforcrossingothers,andviceversa.144

Inshort,almosteverywhereresearchersexplore,theyarefindingevidenceofachangingworldincreasinglydominatedbyacceleratingnonlineareffects,tipping-pointthresholds,multipleinterrelatedpos-itive-feedbackeffects,andlikelyirreversibletrajectoriesoftransfor-mation.Beyond2°C,theworldislikelytolooknothinglikethecom-plexes of social-ecological systems we currently are used to,145includingintheUnitedStates.

Ofcourse,wecannotbecertainaboutwhat the4°Cworldwilllooklikeandjusthowdifferentitwillbe.Forasenseofthat,however,wecanturntopaleoclimaterecords.146Forinstance,dropsinglobalaveragetemperatureof4°Cfrompre-industriallevelshaveledtoiceages.147Intheotherdirection,duringmuchofthePaleoceneandearlyEocene,whenglobalaveragetemperatureswereroughly7°Cwarmerthannow,“thepoleswerefreeoficecaps,andpalmtreesandcroco-dileslivedabovetheArcticCircle.”148Inoneofthemostcomprehen-sive paleoclimate analyses, Nolanet al. concluded that without

144. SeeFrederickvanderPloeg,ReactingtoMultipleTippingPoints,6NATURECLI-MATECHANGE442,442–43(2016)(introducingthestudyofthelikelihoodofeachoffivetippingpointsandhoweachdependsonthestateofothers). 145. SeeNewetal.,supranote24,at6(“Insomecases,suchas farming insub-SaharanAfrica,a+4°Cwarmingcouldresultinthecollapseofsystemsorrequiretrans-formationaladaptationoutofsystems,asweunderstandthemtoday.”). 146. See Jessica E. Tierney, Christopher J. Poulsen, Isabel P. Montañez, TriptiBhattacharya,RanFeng,HeatherL.Ford,BärbelHönisch,GordonN.Inglis,SierraV.Petersen,NavjitSagoo,ClayR.Tabor,KaustubhThirumalai,JiangZhu,NatalieJ.Burls,GavinL.Foster,YvesGoddéris,BrianT.Huber,LindaC.Ivany,SandraKirtlandTurner,DanielJ.Lunt,JenniferC.McElwain,BenjaminJ.W.Mills,BetteL.Otto-Bliesner,AndyRidgwell&YiGeZhang,PastClimatesInformOurFuture,SCIENCE,Nov.6,2020,at7(notingthatimprovedgeochemicalandstatisticaltechniquesareprovidingmorereli-ableprojections frompaleoclimatemodels);ThomasWesterhold,NorbertMarwan,AnnaJoyDrury,DiederikLiebrand,ClaudiaAgnini,EleniAnagnostou,JamesS.K.Bar-net,StevenM.Bohaty,DavidDeVleeschouwer,FabioFlorindo,ThomasFrederichs,Da-vid A. Hodell, Ann E. Holbourn, Dick Kroonvittoria Lauretano, Kate Littler, Lucas J.Lourens,MitchellLyle,HeikoPälike,UrsulaRöhl,JunTian,RoyH.Wilkens,PaulA.Wil-son&JamesC.Zachos,AnAstronomicallyDatedRecordofEarth’sClimateanditsPre-dictabilityOvertheLast66MillionYears,369SCIENCE1383,1383–87(2020)(describ-ingnewtechniquesandresults). 147. HowIsToday’sWarmingDifferentfromthePast?,NASAEARTHOBSERVATORY(June 3, 2010), https://earthobservatory.nasa.gov/features/GlobalWarming/page3.php[https://perma.cc/TP2N-GX9B]. 148. MichonScott&RebeccaLindsey,What’stheHottestEarth’sEverBeen?,NOAACLIMATE.GOV (June 18, 2020), https://www.climate.gov/news-features/climate-qa/whats-hottest-earths-ever-been[https://perma.cc/H2GD-FBEB].


substantialmitigationefforts,allglobalterrestrialecosystemsareatriskofmajortransformationincompositionandstructure.149Inpar-ticular, during thePaleocene-EoceneThermalMaximum (PETM)ofroughly55.9millionyearsago,arapidandsustainedincreaseinat-mosphericCO2overthecourseofafewmillennialedtoasustainedwarmingthatfossilandotherrecordsshow“causedamplifyingfeed-backs,dwarfingoflargeanimals,ecosystemdisruptions,soildegrada-tion,water-cycleshifts,andothermajorchanges.”150“PETMCO2re-mained elevated for over 150,000 years,” suggesting that currentanthropogenicemissionscouldhavesimilarlong-lastingeffects.151

Steppingback,whatdoesallthismeanforhumans?Insomewhatclinicalterms,theIPCChasoutlinedtheimpactsofnonlinearchangebeyond 2°C. For example, the IPCC calculates that both permafrostdegradationandfoodsupplyinstabilityentertherealmofveryhighrisk at 2°C.152 Drylandwater scarcity andwildfire damage becomeveryhighriskat3°Candvegetationlossandtropicalcropyieldde-clinesatabout3.5°C,butsoilerosiondoesnotbecomeveryhighriskuntilaround5°C.153Forwildfiredamage,ourcurrent1°Cincreaseinglobalaveragetemperaturemeansalongerfireseason;at2.5°C,50percentmoreoftheMediterraneanregionisatriskofwildfire;andatabout4.3°C,100millionmorepeopleareatriskfromwildfire.154Withrespecttofoodsecurity,theplanetmovesfrominfrequent,locallyim-portantspikes in foodpricesat1°Cto“periodic foodshocksacross

149. ConnorNolan,JonathanT.Overpeck,JudyR.M.Allen,PatriciaM.Anderson,JulioL.Betancourt,HeatherA.Binney,SimonBrewer,MarkB.Bush,BrianM.Chase,RachidCheddadi,MortezaDjamali,JohnDodson,MaryE.Edwards,WilliamD.Gosling,SimonHaberle,SaraC.Hotchkiss,BrianHuntley,SarahJ.Ivory,A.PeterKershaw,Soo-HyunKim,ClaudioLatorre,MichelleLeydet,Anne-MarieLézine,Kam-BiuLiu,YaoLiu,A. V. Lozhkin,Matt S. McGlone,Robert A. Marchant,Arata Momohara,Patricio I.Moreno, Stefanie Müller,Bette L. Otto-Bliesner,Caiming Shen,Janelle Stevenson,HikaruTakahara,PavelE.Tarasov,JohnTipton,AnnieVincens,ChengyuWeng,Qing-haiXu,ZhuoZheng&StephenT.Jackson,PastandFutureGlobalTransformationofTer-restrialEcosystemsUnderClimateChange,361SCIENCe920,920(2018). 150. RichardB.Alley,AHeatedMirror forFutureClimate:ClimaticChanges55.9MillionYearsAgoResembleThoseExpectedintheFuture,352SCIENCE151,151(2016). 151. Id. 152. See2019IPCCLandReport,supranote56,at16–17fig.SPM.2(“[V]eryhighprobabilityofsevere impacts/risksandthepresenceofsignificant irreversibilityorthepersistenceofclimate-relatedhazards,combinedwithlimitedabilitytoadaptduetothenatureofthehazardorimpacts/risksexistsat2°C.”). 153. Id. 154. Id.

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regions” at 3.2°C to “sustained food supply disruptions globally” atabout4.3°C.155Thelistgoeson.

Whilealarming,theseprojectionsdonotprovidemuchsenseofwhatlifewouldbelikeforhumansunderextremeconditions.Forthat,severalauthorshaveusedavailablescientificevidencetosketchoutnarrativesinwhatmightbetermedscientificspeculation.Forexam-ple,asearlyas2008,MarkLynasconjuredprogressivevisionsoftheworldasglobalaveragetemperaturesincreasefrom1°Cto6°C.156At4°C,placeslikeBangladeshandNewJerseywillrapidlybelosinglandmassandcoastalcitiesaroundtheworld—includingMumbai,Shang-hai,London,Venice,NewYork,andNewOrleans—“maygraduallybe-comefortifiedislands,largelybelowsealevelandundersiegefromallsidesbytheadvancingwaters.”157Atthesametime,foodsecuritybe-comes an international crisis as the world’s “breadbaskets” fail inrapid succession, often replaced by deserts,158while lands recentlyfreedoficeandsnow,likeCanadaandRussia,proveunequaltothetaskofreplacingthem.159Lynasconcludesthat“allof theseregionswillbehaemorrhagingpeople in thebiggesthumanmigrationeverseen,withhundredsofmillionsonthemoveinsearchoffoodandwa-ter,”160and“thatmassstarvationwillbeapermanentdangerformuchofthehumanraceinthefour-degreeworld....”161

Morerecently,asking“Willyourgrandchildren live incitiesonAntarctica?,”FrankJacobsmoreoptimisticallyenvisionsatraumaticbutultimatelysuccessfulhumanmigrationtothepoles.162Incontrast,forGaiaVinceofTheGuardian,4°Cmeans“[d]rownedcities;stagnantseas;intolerableheatwaves;entirenationsuninhabitable...andmorethan11billionhumans.A four-degree-warmerworld is thestuffofnightmaresandyetthat’swherewe’reheadinginjustdecades.”163

155. Id. 156. SeegenerallyMARKLYNAS,SIXDEGREES:OURFUTUREONAHOTTERPLANET(Nat’lGeographiced.2008)(describinghowtheworldwilllookasglobaltemperaturescon-tinuetorise). 157. Id.at187. 158. Id.at195. 159. Id. 160. Id. 161. Id.at196. 162. FrankJacobs,WhattheWorldWillLookLike4°CWarmer,BIGTHINK(May22,2017), https://bigthink.com/strange-maps/what-the-world-will-look-like-4degc-warmer[https://perma.cc/4X2B-PZ2K]. 163. GaiaVince,TheHeatIsonOvertheClimateCrisis.OnlyRadicalMeasuresWill


Whilethesevisionsdifferinthedetails,theyagreeonseveralbigpointsrelevant toadaptationgovernance.First,humanswillbemi-grating enmasse, probablymostly toward the poles asmiddle lati-tudesbecomeincreasinglyuninhabitable.164Second, food insecurityescalatingtomassstarvationwillbecomearealproblemforalmosteveryoneasboth terrestrialandmarine foodsystems fail.165Third,sea-levelrise,meltingiceandincreasingnumbersofincreasinglyse-verestormswilltransformthecoasts,wherehumanityhasbeencon-centratingitself,exacerbatingmigrationpressures.166Fourth,therestof thebiospherewill be sufferingdisproportionatelyboth fromcli-matechange itself and fromhumanity’sattempts toadaptandsur-vive—thesixthglobalmassextinctionofspecieswillbewellunder-way, exacerbated by increasing loss of habitat as a result both ofchanging physical parameters and of new human settlement.167 Fi-nally,whileHomosapiensisunlikelytogoextinct,humansufferingislikelytoincreasedramatically.Underanyconditions,massmigrationisgenerallyaccompaniedbypoorsanitation,poornutrition,nonexist-enthealthcare,andrampantdisease;tothat,climatechangewilladdheatstressandsignificantlyreducedresources(suchasfood)andca-pacityforreliefefforts.168Governmentsandgovernancesystemsneedtobeprepared,orwecancertainlyaddwar,famine,disease,andin-creasedinequalitiesintothenarrative.

Work, GUARDIAN (U.K.) (May 18, 2019), https://www.theguardian.com/environment/2019/may/18/climate-crisis-heat-is-on-global-heating-four-degrees-2100-change-way-we-live[https://perma.cc/R9AK-ZZQY].InterestedreadersmightalsoexploreKimStanleyRobinson’snovelMinistryoftheFutureforanimmersiveim-aginingofamuchwarmerfuture. 164. Formoredetaileddiscussionofhumanmigration,seediscussioninfraPartsIII.CandIV.A. 165. Vince,supranote163;seealsoÉvaPlagányi,ClimateChangeImpactsonFish-eries,363SCIENCE930,930–31(2019)(concludingthattherehasalreadybeena4%declineinglobalproductivityofmarinefisheriesbetween1930and2010). 166. Vince,supranote163. 167. Id. 168. In 2021, for example, theNationalAcademies of Science, Engineering, andMedicine (NASEM) identified risks to Americans from climate change to include“health,food,water,energy,andtransportationsystems,andrisksthataffecttheecon-omyandnationalsecurity.Newresearchisneededtounderstandandcommunicatecomplex interactions among climate change (including uncertainties), other globalchangessuchasdisruptionoftheglobalnitrogencycle,andsocietaldevelopment.”SeeGlobalChangeResearchNeedsandOpportunities for2022–2031,NAT’LACADS.OFSCI.,ENG’G,&MED.2(2021)[hereinafter2021NASEMGlobalChangeResearchReport].

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B. ACKNOWLEDGINGPOTENTIALLIMITATIONSONHUMANITY’SADAPTATIVECAPACITY

Havingestablishedtheprobabilityofplanetarytransformation,anotherpotentialcomplicationforadaptationgovernanceisthathu-mansmightnotbeasadaptabletoawarmerworldastheyliketobe-lieve.Considerfirstthatwhiletheplanethasrepeatedlysupportedathrivingbiosphereataglobalaveragetemperature5°Cto8°Chotterthantoday,humans,asaspecies,haveneverexperiencedthosetem-peratures.169Adaptingtoa4°Chotterworld,therefore,isliterallynotinourDNA.

Nor,possibly, arehumansas temperature flexibleaswemightliketobelieve.Developingtheconceptofthe“humanclimateniche,”Xuetal.emphasizethat,despiteallouradvancesintechnology,even“today,humans,aswellastheproductionofcropsandlivestock...areconcentratedinastrikinglynarrowpartofthetotalavailableclimatespace.”170Theyfurtherconcludethattemperatureisthemaindeter-minantofwherepeoplelive171andthathumanity’stemperaturepref-erenceshavenotchangedforatleast8,000years.172Theseresearch-ers suggest that “[t]his distribution likely reflects a humantemperaturenicherelatedtofundamentalconstraints.”173

Ifhumanthrivingdoesdependonoccupancyofthisfundamentaltemperatureniche,theimplicationsforclimatechangeadaptationareprofound.Warmingnowisoccurringtentotwentytimesfasterthanwhen theplanetwasemerging from its ice ages,174 givingbothhu-mansandecosystemsfarlesstimetomovetothetemperaturezonesthatwillallowthemtocontinuetosurvive.175

C. IMAGININGTHEUNITEDSTATESWHENTHEWORLDIS4°CWARMERWhatwilla4°CwarmerUnitedStateslooklike?Inthesummerof

2020,ProPublicaandtheNewYorkTimespartneredtoaddressthat

169. Vince,supranote163. 170. Xuetal.,supranote34,at11350. 171. Id. 172. Id.at11350–51. 173. Id.at11350. 174. Scott&Lindsey,supranote148. 175. Urbanizationalsoisadriverofrisingpopulationheatexposure,compoundingtheeffectsofclimate-inducedheatexposure.SeeAshleyMarkBroadbent,EricScottKrayenhoff&MateiGeorgescu,TheMotleyDriversofHeatandColdExposurein21stCenturyUSCities,117PROC.NAT.ACAD.SCI.21108,21108–10(2020);KangningHuang,XiaLi,XiaopingLiu&KarenC.Seto,ProjectingGlobalUrbanLandExpansionandHeatIslandIntensificationThrough2050,14ENV’TRSCH.LETTERS,Nov.14,2019,at1–3.


veryquestion.176TheprojectvividlyillustratedthattheUnitedStatesina4°CworldlooksquitedifferentfromtheUnitedStatesat2°C.177Defininga“suitablezone”astheareaofthenationinthesweetspotofXuet al.’s “human climateniche,”178 theproject reveals that thiszonecoversmostoftheheartofthenationtoday,movesnorthwardunderamoderateemissionsscenario, convergingaround theGreatLakes,andalmostcompletelyshifts intoCanadaunderahighemis-sionsscenario.179Puttingthesemapsintodescriptivewords,AbrahmLustgartenoftheNewYorkTimesobservesthat

BuffalomayfeelinafewdecadeslikeTempe,Ariz.,doestoday,andTempeitselfwillsustain100-degreeaveragesummertemperaturesbytheendofthecentury.ExtremehumidityfromNewOrleanstonorthernWisconsinwillmake summers increasinglyunbearable, turningotherwise seemingly sur-vivableheatwavesintodebilitatinghealththreats.Freshwaterwillalsobeinshortsupply,notonlyintheWestbutalsoinplaceslikeFlorida,GeorgiaandAlabama,wheredroughtsnowregularlywithercottonfields.180Thereare two importantpolicypoints todrawfromthisbleak

scenario.First,thesechangeswillmeandifferentthingsacrossthena-tion’salreadyvariedclimate.Forexample,“largeincreasesinheavyprecipitationhave[already]occurredintheNortheast,Midwest,andGreatPlains,whereheavydownpourshavefrequently ledtorunoffthat exceeded the capacity of storm drains and levees, and causedfloodingeventsandacceleratederosion,”whileAlaskaisalreadyex-periencingmeltingpermafrostthatwithbothdestabilizeinfrastruc-tureandaccelerateclimatechange.181Increasedcompetitionforwa-ter—bothamonghumansandbetweenhumansandecosystems—islikelyintheSoutheast,Caribbean,GreatPlains,Hawai’i,thePacificIs-land Territories, and especially the Southwest, which also faces

176. See Abrahm Lustgarten,How ClimateMigrationWill Reshape America,N.Y.TIMES MAG. (Sept. 15, 2020), https://www.nytimes.com/interactive/2020/09/15/magazine/climate-crisis-migration-america.html [https://perma.cc/FA58-3976]; AlShaw,AbrahmLustgarten&JeremyW.Goldsmith,NewClimateMapsShowaTrans-formed United States, PROPUBLICA (Sept. 15, 2020), https://projects.propublica.org/climate-migration[https://perma.cc/DJ7B-7HTT]. 177. Shawetal.,supranote176. 178. SeeXuetal.,supranote34. 179. SeeShawetal.,supranote176. 180. Lustgarten,supranote176. 181. SeeClimateChangeImpactsintheUnitedStates:TheThirdNationalClimateAssessment, U.S. GLOB. CHANGE RSCH. PROGRAM 9 (2014), https://nca2014.global-change.gov/downloads/high/NCA3_Climate_Change_Impacts_in_the_United%20States_HighRes.pdf[https://perma.cc/DV6W-6CF3][hereinafter2014U.S.ClimateImpactReport].

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increasingrisksofcatastrophicwildfires.182Thenation’scoastsarein-creasinglyatriskfromsea-levelriseandworseningstormsurge,es-peciallyintheGulfofMexicoandSoutheast.183Worsening—andlife-threatening—heatwavesareariskeverywhere.

Second, although the direct impacts of sea-level rise, drought,heat,andotherthreat factorsmaybeunevenacrossthenationandacrosseconomicsectors,noregionorsectorcanbecomplacentthatitwillavoiddisruption.Climate-inducedimpactsinoneregionorsectorundoubtedlywillhaveknock-oneffectselsewhere.Forexample, in-creasinglyunlivabletemperaturesinsomeregions,lackofpotablewa-terinotherregions,andtheinvasionoftheseaincoastalregionsarelikelytodrivesignificantinternalmigrationswithintheUnitedStates’borders,meaning that every regionof thenation is affected.184 Re-gionalandsectoralinteractionsfromthisandotherimpacts,suchascropfailuresandwaterscarcity,willonlybemoreintensiveandfarreachingina4°Cworld.185Likewise,theUnitedStateswillfeeleffectsfromaroundtheglobeaswell,whereinallcasessocial-ecologicalsys-temconditionsworsenastemperaturesincrease.186

One need not fully accept all the projections that the ProPub-lica/NewYorkTimesprojectproducedtoappreciatethattheUnitedStatesina4°Cworldwouldjointheranksofnationsperceivedtodayasmostatriskina2°Cworld.187At4°C,theUnitedStates’comparablewealthwill not be enough to stop the “suitable zone” from exitingnorthward.188Welcome,UnitedStates,toaclubnonationwishestojoin.

AstheProPublica/NewYorkTimesprojectemphasizes,themostsignificantconsequenceofthehighemissionsscenariofortheUnitedStatesisinternaldomestichumanmigration.189At2°C,weandotherNorthernHemispheredevelopednationsarethesought-afterrefugeforthehard-hitdevelopingworld.At4°C,wemaystillbe,butthereis

182. Id.at11. 183. Id. 184. See Lustgarten, supra note176.Domestic internalmigration is likely tobeprevalent inmany nations. See François Gemenne, Climate-Induced Population Dis-placementsina4°C+World,369PHIL.TRANSACTIONSROYALSOC’YA182,182–83(2011). 185. SeeRachelWarren,TheRoleofInteractionsinaWorldImplementingAdapta-tionandMitigationSolutionstoClimateChange,369PHIL.TRANSACTIONSROYALSOC’YA217,219–33(2011). 186. See2019IPCCLandReport,supranote56,at8–9. 187. Lustgarten,supranote176. 188. Shawetal.,supranote176. 189. Lustgarten,supranote176;Shawetal.,supranote176.


likelytobesignificantmigrationwithintheUnitedStates,awayfromcoastalregions,awayfromintolerablyhotregions,andawayfromre-gionswithnosustainablepotablewatersupply.190Ironically,asLust-gartenobserves,“hereintheUnitedStates,peoplehavelargelygravi-tated toward environmental danger, building along coastlines fromNewJerseytoFloridaandsettlingacrossthecloudlessdesertsoftheSouthwest.”191Underextremeclimatechange,thegravitationalpullswillbereversed.

Whatthatmeansfordifferentregionsofthenationislikelytobeamixedbag.Inoneinfluentialstudy,geographerMathewHauerme-ticulouslymodeledtheimpactsofsea-levelrise(SLR)oncoastalcom-munitiesandestimateddemandforrelocationintheUnitedStatestobeashighas13millionpeople.192Hismainpoint,however,isthattheyaremovingsomewhereinland,meaninginlandcommunitieswillhavetoadaptaswell.193Fanetal. find that this inter-regionalmigrationlikelywill also redistribute economic fortunes as a result of risingwages and landprices in the in-migration regions.194Other studiesmake predictions about domesticmigration responses to heat andnaturaldisasters,oftenfindingnonlineareffects.195

Themagnitudeand impactsofdomesticclimate-induced inter-regionalmigrationhavebeenlargelyignoredinadaptationplanningintheUnitedStates(andelsewhere), thespotlightbeinginsteadoncross-borderinternationalmigration.196Newmodalitiesofadaptationgovernancewillbenecessarytocopewiththeimpactsofmassdomes-ticmigrationandthemanyothertransformationsoccurringina4°Cworld.197WeturntothatthemeinthenextPart.

190. Shawetal.,supranote176. 191. Lustgarten,supranote176. 192. MathewE.Hauer,MigrationInducedbySea-LevelRiseCouldReshapetheUSPopulationLandscape,7NATURECLIMATECHANGE321,321–25(2017). 193. Id. 194. QinFan,KarenFisher-Vanden&H.AllenKlaiber,ClimateChange,Migration,andRegionalEconomicImpactsintheUnitedStates,5J.ASS’NENV’T&RES.ECONOMIST643,644–45(2017). 195. Id.at643–44. 196. SeeGemenne,supranote184,at187–88. 197. W.NeilAdger,Anne-SophieCrépin,CarlFolke,DanielOspina,F.StuartChapinIII,KathleenSegerson,KarenC.Seto,JohnM.Anderies,ScottBarrett,ElenaM.Bennett,GretchenDaily,ThomasElmqvist,JoernFischer,NilsKautsky,SimonA.Levin,JasonF.Shogren,JeroenvandenBergh,BrianWalker&JamesWilen,Urbanization,Migration,andAdaptationtoClimateChange,3ONEEARTH396,396(2020).

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III.ADAPTINGTO4°C:REORIENTINGADAPTATIONPOLICYFORANTICIPATORYREDESIGN

Climatechangeadaptationpolicytookabackseattomitigationpolicyuntiladecadeago,whenitbecameclearthatsevereandpro-tractedharmswouldoccurevenifthe(atthattime)1.5°Cgoalcouldbeachieved.198Indeed,insomepolicycircles,speakingofadaptationwasforbidden,lestitspotentialforalleviatingharmsuppressessup-portforaggressive,costlymitigationpolicy.199Theinevitabilityofris-ing sea levels, hotter climates, bigger storms, and other conditionseventuallyforcedadaptationintothepolicydiscussion,anditisnowseenasanessentialpartnerofmitigationpolicyforbothhumancom-munitiesandconservationresources.200Adaptationpolicy201nowfo-cusesonkeydrivers,including:(1)coastalflooding;(2)inlandflood-ing;(3)weather-eventdisruptionofelectrical,emergency,andotherkeyinfrastructuresystems;(4)extremeheat;(5)foodinsecurity;(6)watershortages;(7)marineecosystemdegradation;and(8)terres-trialandinlandwaterecosystemdisruption.202

Nevertheless,adaptationpolicyhaslargelycenteredaroundthe1.5°–2°C scenario,203 although more recently cities in the UnitedStateshavebeguntoincludeahighemissionsscenariointheiradap-tationplans.204The1.5°–2°Cscenarioisnotpleasantbyanystretch,butitisnotnearlyasdisruptiveanddifficulttomanageasthe4°Csce-nariodescribedinPartII.InthisPartwematchupthecurrentadap-tationpolicymodelagainstthe4°Cscenario.Weconcludethecurrentmodelisnotuptothechallenge,inlargepartbecauseprogressivelyincreasing temperatures geometrically, rather than arithmetically,

198. Forahistoryoftheemergenceanddevelopmentofadaptationpolicyandre-search,seeJ.B.Ruhl,ClimateChangeAdaptationandtheStructuralTransformationofEnvironmentalLaw,40ENV’TL.363,365–75(2010).SeealsoXueqingShan,Coordinat-ingLocalAdaptiveStrategiesThroughaNetwork-BasedApproach,29DUKEENV’TL.&POL’YF.183,187(2018). 199. Ruhl,supranote198,at366–70. 200. Id. 201. Jacobs,supranote162. 202. EliKintisch,InNewReport,IPCCGetsMoreSpecificAboutWarmingRisks,344SCIENCE21,21(2014);seealsoAdaptNow:AGlobalCallforLeadershiponClimateRe-silience, GLOB. COMM’N ON ADAPTATION 3 (2019) https://gca.org/wp-content/up-loads/2019/09/GlobalCommission_Report_FINAL.pdf [https://perma.cc/9GYN-969W][hereinafterAdaptNow](identifyinghuman,environmental,andeconomicim-perativestoadaptquickly). 203. SeeWarren,supranote185,at218–19. 204. SeeMissyStults&LarissaLarsen,TacklingUncertainty inUSLocalClimateAdaptationPlanning,40J.PLAN.EDUC.&RSCH.416,420,425(2020).


increase the disruptions to social-ecological systems from climatechange.205 In particular, domestic inter-regional migration in theUnitedStateswilldisrupt thepopulation landscape,with cascadingconsequentimpacts.206Asaresult,weproposethatanewframingisneededinordertoprepareforadaptationbeyond2°C,aframingwecallredesign.

A. RESISTANCE,RESILIENCE,ANDRETREATAlthoughtherearedifferentformulationsandterminologies,cur-

rentclimatechangeadaptationpolicycanbesortedintothreemodes:resistance(alsoknownasprotect,fortify,ordefend),resilience(alsoknownasadjustment,accommodate,manage,ortransform),andre-treat(alsoknownasmove,resettlement,relocation,oravoidance).207

Thesemodalitiesarenotnecessarilymutuallyexclusiveand inmanycontextsmayneedtobedeployedsimultaneously—forexam-ple,evenifMiamieventuallyneedstouseretreataspartofitsstrat-egy,itspopulationneedstobeprotectedandresilientduringthetimeittakestomoveandthenintheirresettledpartofthecity.208Never-theless,the“ThreeRs”aredistinctintermsoftheircoreorientationstoanadaptationresponse.209

1. ResistanceResistance policies focus on building infrastructure and other

mostlytechnologicaldefensestoclimatechangeimpactsinorderto

205. SeeinfraPartII.A. 206. SeeinfraPartII.A. 207. SeeRuhl,supranote198,at387–89(usingthetermsresist,transform,move);seealsoRobertR.M.Verchick&JoelD.Scheraga,ProtectingtheCoast,inLAWOFADAP-TATION,supranote25,at239(using the termsresistance,adjustment,andretreat);TripPollard,DamageControl:AdaptingTransportationtoaChangingClimate,39WM.&MARYENV’TL.&POL’YREV.365,378(2015)(listingthevariousterms);MarkScott&MickLennon,ClimateDisruptionandPlanning:ResistanceorRetreat?,21PLAN.THEORY&PRAC.125,130(2020)(usingavarietyoftheseterms);A.R.Siders&JesseM.Keenan,VariablesShapingCoastalAdaptationDecisionstoArmor,Nourish,andRetreatinNorthCarolina,183OCEAN&COASTALMGMT.,Jan.1,2020,at2. 208. SeeJeroenC.J.H.Aerts,W.J.WouterBotzen,KerryEmanuel,NingLin,HansdeMoel&ErwannO.Michel-Kerjan,EvaluatingFloodResilienceStrategiesforCoastalMegacities,344SCIENCE473,473–75(2014)(evaluatingdifferentmixesofstrategiesbasedonevidencefromNewYorkapproachestofloodresilience);AudreyBaills,Ma-nuel Garcin & Thomas Bulteau, Assessment of Selected Climate Change AdaptationMeasuresforCoastalAreas,185OCEAN&COASTALMGMT.105059,at4–5,7(2020)(out-liningabroadarrayofstrategiesandcriteriaforevaluatingselection). 209. SeeRuhl,supranote198,at383(distinguishingbetweenproactiveandreac-tiveadaptationstrategiestoclimatechange).

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protecthumancommunities.210ResistancehaslongbeenacorepolicyapproachtonaturalhazardsintheUnitedStates.211Classicexamplesincludeseawallsalongcoastalareasanddamsandleveesalongflood-pronerivers.212Itisnosurprise,therefore,thatresistancestrategiesareprominentinmanylocalandregionalclimatechangeadaptationplans.213Resistancestrategiesarelesslikelytobeeffectiveforconser-vationlands,however,whereclimatechangewilldirectlyaltereco-logicalresourcesandprocessesinwaysthatwouldbedifficultifnotimpossibletoprevent.214

Resistancepolicieshavebeencriticized fromanumberofper-spectives, even in the purely disaster-prevention context.215 One isthat they encourage development in the protected area, exposingmorepeopleandcapitaltoriskiftheinfrastructurefails.216Anotheristhattheyareexpensiveandthusmostlikelytobeusedtoprotectaf-fluent andpolitically powerful populations.217 Resistance strategiesoftentaketheformof“hard”infrastructure,whichalmostinevitablycomeswithsignificantenvironmental impacts, from interruptionofsand and sediment flows to blocked animalmigration pathways to

210. SeeRuhl,supranote198,at385–86;seealsoRobertR.M.Verchick&JoelD.Scheraga,ProtectingtheCoast,inLAWOFADAPTATION,supranote25,at235–37;Mach&Siders,supranote39. 211. Cf.RobertR.M.Verchick& JoelD.Scheraga,Protecting theCoast, inLAWOFADAPTATION,supranote25,at240–50(discussingthefederalframeworkandimplica-tionsofAmericanfortificationprojects). 212. SeeScott&Lennon,supranote207,at130–31,142;seealsoRobertR.M.Ver-chick&JoelD.Scheraga,ProtectingtheCoast,inLAWOFADAPTATION,supranote25,at240. 213. SeeAertsetal.,supranote208,at474(discussingNewYorkCityresistancestrategiesandcosts);Baillsetal.,supranote208,at2(evaluatingcoastaladaptationmeasuresintheAquitaineregionofsouthwesternFrance). 214. See Katherine R. Clifford, Laurie Yung, William R. Travis, Renee Rondeau,BetsyNeely,ImtiazRangwala,NinaBurkardt&CarinaWyborn,NavigatingClimateAd-aptationonPublicLands:HowViewsonEcosystemChangeandScaleInteractwithMan-agementApproaches,66ENVT’LMGMT.614,615–16(2020) (“[R]esistancestrategiesbecomemorelabor-intensiveandlesseffectiveovertime.”). 215. SeeScott&Lennon,supranote207,at142(criticizing“protectionandaccom-modation”becausetheyare“expensiveandallowcontinuedinvestmentinvulnerableareas”). 216. SeeScott&Lennon,supranote207,at126–27(“[T]hesehouses[are]beingaccommodatedinareasvulnerabletowildfires.”);RobinKundisCraig,CoastalAdapta-tion,Government-Subsidized Insurance,andPerverse Incentives toStay,152CLIMATICCHANGE215,220–24(2019)(emphasizingthattheNationalFloodInsuranceProgramfacilitates“rebuildinginriskyareas,ratherthanencouragingpropertyownerstomi-grateinland”). 217. Scottetal.,supranote207,at130–31.


altered habitat.218 This conventional approach conflicts with thegrowingadvocacyfornaturalor“green”approaches,suchasenhanc-ingcoastalwetlands.219

For4°Cclimateadaptation,alloftheseobjectionstoresistancestrategiesremain,withtheaddeddisincentivethatthescaleofneces-sary deployment presents staggering economic costs.220 Resistancestrategies,while likelynecessary formanycommunities(at least intheshortterm),thusmustbecarefullyplannedtoavoidspendingex-cessiveamountsofmoney221oninfrastructurethatexacerbatessocialinequity,222environmentaldegradation,223anddisasterrisk224andin-creasesconflictamongcommunityadaptationstrategies inordertoprovidelocalprotectionthatlastsonlyascantfewyears.225

2. ResilienceClimate resilience policies are designed to facilitate a commu-

nity’scapacitytocopewithclimatechangewhereimpactscannotbeavoidedoreffectivelyresisted.226Forexample,thereisnoconceivablewayacitycouldpreventambientairtemperaturesfromincreasingorhalt sea-level rise, but it could subsidize air conditioning to make

218. SeeRobertR.M.Verchick&JoelD.Scheraga,ProtectingtheCoast,inLAWOFADAPTATION,supranote25,at240–41. 219. Id. at 250–51. See generally Siddharth Narayan,MichaelW. Beck, Borja G.Reguero,IñigoJ.Losada,BregjevanWesenbeeck,NigelPontee, JamesN.Sanchirico,JaneCarterIngram,Glenn-MarieLange&KellyA.Burks-Copes,TheEffectiveness,CostsandCoastalProtectionBenefitsofNaturalandNature-BasedDefences,PLOSONE,May2,2016,at5–6(assessingthebenefitsofcoastalrestoration);NikiL.Pace,WetlandsorSeawalls?—Adapting Shoreline Regulation to Address Sea Level Rise and WetlandPreservationintheGulfofMexico,26J.LANDUSE&ENV’T.L.327,340–41(2011)(dis-cussingtheenvironmentalbenefitsofusing“livingshorelines”topreservewetlands). 220. Forexample,usingamoderateemissionsscenario,arecentstudyestimatesthatadequatelyprotectingcoastal communities fromsea level risewouldcostover$400billionoverthenext20years.SeeSverreLeRoy&RichardWiles,HighTideTax:ThePricetoProtectCoastalCommunitiesfromRisingSeas,CTR.FORCLIMATEINTEGRITY1 (2019) https://www.climatecosts2040.org/files/ClimateCosts2040_Report-v4.pdf[https://perma.cc/8NXV-7NLE]. 221. Seeid. 222. SeeScott&Lennon,supranote207,at126–27,130–31. 223. SeePace,supranote219,at338–39. 224. SeeScott&Lennon,supranote207,at142. 225. Seeid.at142–44(discussingthedifficultiesofplannersandofficialsinimple-mentingaccommodationandretreatstrategiesinFloridacommunities). 226. SeeRuhl,supranote198,at385–86;RobertR.M.Verchick&JoelD.Scheraga,ProtectingtheCoast,inLAWOFADAPTATION,supranote25,at239(referringtoadjust-ment); see also Mach& Siders, supra note 39, at 1294 (discussing accommodationmeasuresto“reducesensitivitytohazards”).

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indoorconditionsmorehospitableandadoptbuildingandplanningcodesthatintegrateheat-consciousandflood-consciousdesign.227Re-silience policy goes beyond technology and responsemanagement,however,associalandeconomicsystemcapacitiesalsocontributetoacommunity’soverallresiliencenotonlytoclimatechangebutalsotoother disruptions.228 Such strategies can range from new forms oftrainingtotheconsciousdiversificationofindustryandotherformsofincome.229

Likeresistancestrategies,enhancingresiliencecapacity,particu-larly through technology and response-management strategies, haslongbeenafocusofpublicpolicyindependentofclimatechange.230Technology-basedresiliencegenerallyallowsinfrastructureto“bendratherthanbreak”duringnaturaldisastersandincludeshomesele-vatedonstiltsincoastalareasandarchitecturalinnovationsthatal-lowskyscrapersinearthquake-proneareastosway.231Managementstrategies,inturn,changenormalsocialandcommercialfunctionsinresponse tospecificeventsor triggers,232 suchaswhentheFederalEmergency Management Agency (FEMA) activates new emergencysupplychainsandprovidestemporaryhousinginresponsetohurri-canes.233

Likeresistance,therefore,climateresiliencestrategiesareanat-uralextensionofpastpolicyandhaveplayedamajorrolethusfarinclimateadaptationpolicy.234Moreover,somenewformsofresiliencestrategiesare likely tobenecessary fora4°C future, fromadaptive

227. SeegenerallySierraC.Woodruff,SaraMeerow,MissyStults&ChandlerWil-kins,Adaptation toResiliencePlanning: Alternative Pathways to Prepare for ClimateChange,J.PLAN.EDUC.&RSCH.1,2(2018)(“Resilienceplansgenerallytakeamore‘sys-tems’orintegratedapproachtomanagingriskandaremoreparticipatory,whichisconsistentwiththeoriesofurbanresilience.”). 228. Seeid.at1–3. 229. Seeid.at8(quotingcityofficialsonhowresilience“meanstacklingsystemic,interdependent challenges, such as equitable access to quality education and jobs,housingsecurity,communitysafetyandvibrantinfrastructuretobetterprepareusforshockslikeearthquakesandstresseslikeclimatechange.”). 230. Seeid.at1–3. 231. Cf.Aertsetal.,supranote208,at474(“Implementingimprovedcost-effectivebuildingcodes...suchaselevatingnewbuildingsandprotectingcriticalinfrastructurebyincludingadaptationmeasuresintomaintenanceworks—isthemostcost-effectivestrategy.”). 232. SeeWoodruffetal.,supranote227,at1–3. 233. Cf.Craig,supranote216,at217(discussingcongressionalpassageoftheNa-tional Flood Insurance Act as a supplement to federal disaster relief provided byFEMA.). 234. SeeWoodruffetal.,supranote227,at1–3.


training in the health care sector in response to emerging healththreats235 to cropdiversification inagriculture.236Resilience strate-giesalsocanplayaroleforconservationlands,wheremanagers,rec-ognizingthatmanychangeswillbeunavoidable,turntheirattentiontomaintainingoverallresilienceindynamicallytransformingecosys-tems.237Nevertheless,resiliencestrategiesarealsosubjecttomanyofthesamecriticismsasresistance.238

3. RetreatRetreatpoliciesfocusonintentionallyabandoningareassubject

toharmsandrelocatingthepeopleandstructurestolessvulnerablelocations.239 In the context of climate change adaptation, retreatcomesintoplaywhenitisanticipatedthatresistandresiliencepoli-cieswillnotbetechnologicallyoreconomicallypracticableorsuffi-cientlyeffectiveforreducingoravoidingharms.240Forexample,sea 235. SeeRobinKundisCraig,CleaningUpOurToxicCoasts:APrecautionaryandHumanHealth-BasedApproachtoCoastalAdaptation,36PACEENV’TL.REV.1,40–47(2018);RobinKundisCraig,OceansandCoasts,inCLIMATECHANGE,PUBLICHEALTH,ANDTHELAW204,220–22(MichaelBurger& JustinGundlacheds.,2018);RobinKundisCraig,CholeraandClimateChange:PursuingPublicHealthAdaptationStrategiesintheFaceofScientificDebate,18HOUS.J.HEALTHL.&POL’Y29,56–67(2018). 236. SeeRebeccaCarter,TylerFerdinand&ChristinaChan,TransformingAgricul-tureforClimateResilience:AFrameworkforSystemicChange1(WorldRes.Inst.,Work-ingPaperNo.1,2018)(“Beginningnowtoidentify,planfor,andfinancetransforma-tiveapproachesoverthecomingdecadesoffersthebestopportunitytomaintainandenhanceglobalfoodsecurity,avoidmaladaptation,andreduceescalatingrisksofcon-flictandcrisisasclimateimpactsintensify.”). 237. Cliffordetal.,supranote214,at616. 238. See Scott & Lennon, supra note 207, at 130–31. See generally Shalanda H.Baker,Anti-Resilience:ARoadmapforTransformationalJusticeWithintheEnergySys-tem,54HARV.C.R.-C.L.L.REV.1,25–37(2019)(challenginghowresiliencehasbeenpursuedasagoalinenergypolicy). 239. SeeRuhl,supranote198,at388–89;RobertR.M.Verchick&JoelD.Scheraga,ProtectingtheCoast,inLAWOFADAPTATION,supranote25,at239;Mach&Siders,supranote39.ForacomprehensiveoverviewofcoastalretreatlawandpolicyintheUnitedStates,seeJ.PeterByrne&JessicaGrannis,CoastalRetreatMeasures,inLAWOFADAP-TATION,supranote25,at267–306. 240. SeeJohnCarey,ManagedRetreatIncreasinglySeenasNecessaryinResponsetoClimate Change’s Fury, 117 PROC. NAT. ACAD. SCI. 13182, 13183–85 (2020); BrentDoberstein,AnneTadgell&AlexandraRutledge,ManagedRetreatforClimateChangeAdaptation inCoastalMegacities:AComparisonofPolicyandPractice inManilaandVancouver,253J.ENV’TMGMT.109753,109753–54(2020);MiyukiHino,ChristopherB.Field&KatharineJ.Mach,ManagedRetreatasaResponsetoNaturalHazardRisk,7NATURECLIMATECHANGE 364, 364–65 (2017);AndreaMcArdle,Managing “Retreat”:TheChallengesofAdaptingLandUsetoClimateChange,40U.ARK.LITTLEROCKL.REV.

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wallsmayprotectacoastalcommunityagainststormsurge,buttheywillnotpreventsaltwaterintrusiontogroundwaterassealevelrises,anditmaybecostprohibitivetoreplacetheimpaireddrinkingwatersourcewithothersources.241Inland,areasonthewildland-urbanin-terfacemayexperiencemorefrequentandintensewildfiresthatcan-not be adequately prevented and controlled.242 At some point re-sistanceandresiliencestrategiesmaysimply fail tomanage risk toacceptablelevelsatacceptablecost,leavingretreatastheonlyviableoption.243Asaresult,“[r]etreathasoftenbeenviewedasafailuretoadaptorconsideredonlywhenallotheroptionsareexhausted.”244

In climateadaptationpolicy, retreat isusuallydescribedas lo-cally“managed,”inthatthereisadeliberatepolicyregimeandadmin-istratordesignedtocarryoutanorderlyprocessformovingthebuiltenvironmentandsub-communitiesoutofharm’sway,ideallywellbe-foretheharmsbecomesignificant.245Moreover,asMachandSiderspointout,carefuldeliberationaboutandplanningofretreatcantrans-formthisputativefailureinto“anadaptiveoptionthatcanproactivelysupport social values through a plurality of specificmeasures,” notonlyreducingriskbutsimultaneouslyincreasingsocialequityandin-creasing economic efficiency.246 Nevertheless, although voluntarypost-disasterretreatprogramshavebeenimplementedinvariouslo-cationsintheUnitedStates,247MachandSiders’visionof“pre-emp-tive” retreat—retreat forced andmanaged inanticipation of condi-tions that will eventually exceed the capacity of resistance andresiliencestrategies248—hasnotyetbeenwidely implementedany-whereintheUnitedStatesandsurelywouldfacestiffpushbackfrom

605,618–24(2018);A.R.Siders,ManagedRetreat intheUnitedStates,1ONEEARTH216,216–19(2019). 241. Scott&Lennon,supranote207,at131. 242. Carey,supranote240,at13183. 243. Seeid.at13182–85. 244. Mach&Siders,supranote39(citationsomitted). 245. SeeCarey,supranote240,at13182–85;seealsoByrne&Grannis,supranote239,at268(“Localgovernmentswillbetheprimaryactorsinimplementingretreatpolicies.”). 246. Mach&Siders,supranote39. 247. SeegenerallyKatieSpidalieri& JessicaGrannis,Managing theRetreat fromRising Seas, GEO. CLIMATE CTR. (2020), https://www.georgetownclimate.org/files/MRT/GCC_20_Taholah-3web.pdf [https://perma.cc/88F5-KSVQ] (providing a seriesof17examples). 248. SeeGibbs,supranote46,at108.


manyinterests,notjustthepeoplebeingrelocated.249ThereisalonghistoryofforcedrelocationsintheUnitedStatesandelsewhere,andtheyhavealmostalwaysbeencontroversial.250Evenwhenrelocationistheonlyalternativeandrelocationsareprovidedwithinthesamegeneralarea,itdisruptscommunityandculture.251

Despitetheserealitiesandpoliticalresistance,retreatisincreas-inglybeingincludedinpolicydiscussionsaseitherapotentiallynec-essaryormorecost-effectiveadaptationstrategyforhumancommu-nities,particularlyamongPacificIslandnationsalreadyatexistentialriskfromclimatechangeandsealevelrise.252Moreover,retreatisin-creasingly recognized as a potentially creativemode of adaptationthatcannotonlyrespondtoavarietyofclimatechange-inducedrisksbutalsoaccommodateavarietyofsocialvalues,includingincreasedequity.253Whileretreat ismoredifficultto implementforconserva-tion lands,whichhave fixedboundaries,254proposals formigratoryconservation spaces do exist,255 and assisted migration—the 249. See id. at 107–08, 111 (“Political hazard and risk can emerge ... with thepreemptiveretreatoptionforownersofhigh-valueforeshoreproperties,whomayfeelliketheyarebeingforciblyrelocatedtoavoidsomeambiguousfuturerisk.”);Siders,supranote240,at218(“ManagedretreathasbeenlimitedintheUSbynumerousbar-riers.”).ThisisnotbyanymeanslimitedtotheUnitedStates.SeeChristinaHanna,IainWhite&BruceGlavovic,TheUncertaintyContagion:RevealingtheInterrelated,Cascad-ingUncertaintiesofManagedRetreat,12SUSTAINABILITY736,737(2020)(presentingacasestudyofNewZealandandindicatingthat“attemptstoimplementmanagedre-treatinvokepublicdisputeandlitigation”);JudyLawrence,JonathanBoston,RobertBell,SamOlufson,RickKool,MatthewHardcastle&AdolfStroombergen,ImplementingPre-Emptive Managed Retreat: Constraints and Novel Insights, 6 CURRENT CLIMATECHANGEREPS.66,68–70(2020)(discussingbarrierstopre-emptiveretreatimplemen-tation);Mach&Siders,supranote39,at1294,1295–96(presentingageneralsurveyof frequencyandtypesofretreatgloballyanddiscussingchallengesto implementa-tion). 250. Carey,supranote240,at13182–83;Hinoetal.,supranote240(indicatingthat“[o]verthepastthreedecades,approximately1.3millionpeoplehaverelocatedthroughmanagedretreat”(citationomitted)). 251. Carey,supranote240,at13184–85;Hinoetal.,supranote240,at364–65;Hannaetal.,supranote249. 252. Carey,supranote240,at13183. 253. Mach&Siders,supranote39,at1296–99. 254. SeegenerallyCliffordetal.,supranote214,at614–17(discussingapproachestoclimateadaptationonpublicland). 255. Notably,however,mostof theproposals focusontheocean,whereprivatepropertyisfarlessofabarrier.SeeROBINKUNDISCRAIG,COMPARATIVEOCEANGOVERN-ANCE:PLACE-BASEDPROTECTIONSINANERAOFCLIMATECHANGE155–69(2012)(discuss-ing anticipatory and dynamic zoning); Josh Eagle, JamesN. Sanchirico& BartonH.Thompson,Jr.,OceanZoningandSpatialAccessPrivileges:RewritingtheTragedyofthe

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translocationofspeciesfromdegradinghabitatstoexistingoremerg-ing suitable habitats—can be thought of as a form ofmanaged re-treat.256

However,itisimportanttorememberthroughoutthisdiscussionof human adaptation responses that ecosystems are already bothchangingcompositionallyandshiftinggeographically—thatis,trans-formingandretreating.257Assuch,ecologicalchangeallbyitselfisin-creasingly likely to perturb long-established social-ecological rela-tionships, whether those be ranching communities in Montana,258sportfishing-dependent communities inWisconsin,259 or salmon-fo-cusedTribesinthePacificNorthwest.260

B. THETHREERSVERSUS4°CCurrent adaptation policy proposes deploying the Three Rs to

manage thekeydriversof adaptationneed.261 Theemphasis in theUnitedStates(andelsewhere)hasbeenonusingincrementaladapta-tiontokeephumancommunitiesmostly intact, insitu,andclosetonormal,withplace-basedsecurityforpeopleandpropertytheover-arching goal.262 Of course, it makes sense that a city’s or region’s RegulatedOcean,17N.Y.U.ENV’TL.J.646,651–65(2008)(discussing“theapplicationofcomprehensivezoningtoU.S.oceanspace”). 256. SeeJedediahF.Brodie,SusanLieberman,AxelMoehrenschlager,KentH.Red-ford,JonPaulRodríguez,MarkSchwartz,PhilipJ.Seddon&JamesE.M.Watson,GlobalPolicy for Assisted Colonization of Species, 372 SCIENCE 456 (2021); Alejandro E.Camacho,AssistedMigration:RedefiningNatureandNaturalResourceLawUnderCli-mateChange,17YALEJ.ONREGUL.171,202–10(2010). 257. SeeCamacho,supranote256,at228(emphasizingthatecologicalmanage-mentshouldaccountforthatcharacterof“perpetuallychangingecologicalcommuni-ties”). 258. SeeAnneCantrell,MSUStudy:ClimateChangeGeneratingAnxietyandDistressforMontanaFarmers,Ranchers,MONT.STATEU.(Apr.23,2020),https://www.montana.edu/news/19885/msu-study-climate-change-generating-anxiety-and-distress-for-montana-farmers-ranchers[https://perma.cc/7UT4-HAKB]. 259. SeeElizabethWeise,GlobalWarmingCouldMeanFewerFishforSportFishing,More Die-Offs Across US, USA TODAY (July 9, 2019), https://www.usatoday.com/story/news/nation/2019/07/09/global-warming-killing-fish-hurting-sportfishing-industry/1675771001[https://perma.cc/VX63-9RMT]. 260. See Salmon and Climate Change, TULALIP TRIBES NAT. RES. DEP’T (2017),https://nr.tulaliptribes.com/Topics/ClimateChange/SalmonAndClimateChange[https://perma.cc/Q2DQ-DA3C]. 261. See 2014U.S. Climate Impact Report, supra note 181, at 201–02, 671–706(discussing“[a]daptationinthecontextofbiodiversityandnaturalresourcemanage-ment”);AdaptNow,supranote202,at9–11,19–21,31–34. 262. SeeMach&Siders,supranote39(“Todate,managedretreatprojectshave


adaptationplanwouldfocusonmanagingadaptationneedsofthecityor region.263Butevenournationaladaptationstrategy,when therehasbeenone,hasbeenfocusedprimarilyonhowtosupportthoselo-calandregionalstrategies,andadaptationisalmostalwayspresentedasanadjuncttomitigation.264PresidentBidenhadtheUnitedStatesrejointheParisClimateAccordonhisfirstdayinofficeandissuedhisClimateChangeExecutiveOrderontheeighth.265Whiletheseareex-cellentsignalsoftheAdministration’sprioritizationofclimatechange,thefocusremainsprimarilyonmitigation,withadaptationprovisionsfocusingonbuildinginsituresilience.266

Thisfocusonincremental,insituadaptationcarriedoutlargelyatstateandlocalscaleshasledtoaheavyemphasisonresistanceandresiliencestrategies,267eventothepointofenvisioning“future-proof-ing”or“climate-proofing”citiesandregions.268Managedretreathas

beenlargelyincremental,minoradjustmentsimplementedusingahandfulofpolicytools,guidedbyalimitedsetofsocialvalues,andsmallscaleintheircontributionstoclimatechangeadaptation.”);SaraHughes,AMeta-AnalysisofUrbanClimateChangeAdaptationPlanningintheU.S.,14URB.CLIMATE17,23(2015)(“[U]rbanadaptationplanningisprimarilyframedas,andmotivatedby,theneedtoprotectvaluableassetsandreducethecity’svulnerability.”);RobertW.Kates,WilliamR.Travis&ThomasJ.Wilbanks, Transformational Adaptation When Incremental Adaptations to ClimateChangeareInsufficient,109PROC.NAT.ACAD.SCI.7156,7156(2012). 263. SeegenerallyAdaptNow,supranote202,at27(“[A]climate-smartapproachrequirespackagesofmeasurestailoredtolocalconditions”). 264. SeeTHEPRESIDENT’SCLIMATEACTIONPLAN,EXEC.OFF.PRESIDENT12(June2013),https://obamawhitehouse.archives.gov/sites/default/files/image/president27sclimateactionplan.pdf [https://perma.cc/3HCJ-NR7Z].PresidentTrumprescindedtheplanandprovidednoreplacement.Exec.OrderNo.13,783,82Fed.Reg.16,093,16,094(Mar.28,2017). 265. Exec.OrderNo.14,008,86Fed.Reg.7,619(Jan.27,2021)[hereinafterBIDENCLIMATECHANGEE.O.]. 266. TheExecutiveOrder,forexample,mentionsadaptationonlyinsection211.Id.at7619–22,7625–26. 267. SeegenerallyKatesetal.,supranote262(“Wethinkofincrementaladapta-tionstochangeinclimateasextensionsofactionsandbehaviorsthatalreadyreducethe losses or enhance the benefits of natural variations in climate and extremeevents.”);Scott&Lennon,supranote207,at142(“Floridaofficials...havemostoftentakentheshort-termviewof‘engineering’resilience...orsometimestoaccommodatedevelopmenttothehazard.”(citationsomitted)).ThisisbynomeanslimitedtotheUnitedStates.See JustineBell&MarkBaker-Jones,RetreatfromRetreat—TheBack-wardEvolutionofSea-LevelRisePolicyinAustralia,andtheImplicationsforLocalGov-ernment, 19 LOC.GOV’TL.J. 23, 24–30 (2014) (describing a shift in policy “towardsgreaterregulationandcontrolofdevelopmentincoastalareas”). 268. See Eye of the Storm, REBUILD TEX. 154–57 (2018), https://www.re-buildtexas.today/wp-content/uploads/sites/52/2018/12/12-11-18-EYE-OF-THE-

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beenaddedasalastresortinmostinstancesandisportrayedaspartofalocalstrategythatretainstherelocatedpopulationandbusinesseswithinthegenerallocale.269Tobesure,itisgenerallyrecognizedthatadaptationwilltransformhowmanycommunitieslookandoperate,buttheoverwhelmingpolicygoalinmostadaptationplansistostayput.270Forconservationresources,movingisgenerallynotanoption,sostayingputmeansdealingwithtransformationthroughresiststrat-egies(suchasremovinginvasivespecies271)andresiliencestrategies(suchasmanaging fire fuelsources272),althoughtherehasbeen in-creasingattentiontoassistedtransformationstrategiesinstead—thatis,onguidingtheconservationlandsintodifferentbutstillproductiveecosystemstates.273

Theemphasisonadaptinginplaceisnotsurprising,asitwouldbepoliticallyunwiseforalocalgovernmenttodeclarethatitsadapta-tionpolicyistodismantlethecityandpromoteout-migration,whileconservationresourcemanagersfacetherealitythatmovingthepro-tected land boundaries is generally not an option.274 Nevertheless,

STORM-digital.pdf [https://perma.cc/3GN2-TL3R] (adopting the “future-proofing”theme); The EU Strategy on Adaptation to Climate Change, EUR. COMM’N 2 (2013),https://ec.europa.eu/clima/system/files/2016-11/eu_strategy_en.pdf[https://perma.cc/MMV5-JJW4](adoptingthe“climate-proofing”themeinAction6). 269. SeegenerallyGibbs,supranote46,at107–08(discussingthecharacteristicsandimplementationofpre-emptive,just-in-time,andreactiveretreat);Siders,supranote240,at217–18(citingthebenefitsandobstaclesofmanagedretreat). 270. SeegenerallyKatesetal.,supranote262,at7156–59(“Conceptionsofself-identityandsenseofplaceandpreferencesforstabilityoverdisruptionmakereloca-tionverydifficult.”). 271. SeeEvelynM.Beaury,EmilyJ.Fusco,MichelleR.Jackson,BrittanyB.Laginhas,ToniLynMorelli,JenicaM.Allen,ValerieJ.Pasquarella&BethanyA.Bradley,Incorpo-ratingClimateChangeintoInvasiveSpeciesManagement:InsightsfromManagers,22BIOLOGICALINVASIONS233,233–34(2020)(seeking“tofacilitateproactiveinvasivespe-ciesmanagementthatalsoaccountsforclimatechange”);seealsoEricV.Hull,ClimateChangeandAquatic Invasive Species:BuildingCoastalResilienceThrough IntegratedEcosystemManagement,25GEO.INT’LENV’TL.REV.51,82–93(2012). 272. SeeP.M.Fernandes,ForestFuelManagementforFireMitigationUnderClimateChange,inFORESTMANAGEMENTOFMEDITERRANEANFORESTSUNDERTHENEWCONTEXTOFCLIMATECHANGE:BUILDINGALTERNATIVES FOR THECOMINGFUTURE 31, 33–37 (ManuelEstebanLucas-Borjaed.,2013). 273. SeeDavidG.Angeler,BrianC.Chaffin,ShanaM.Sundstrom,AhjondGarme-stani,KevinL.Pope,DanielR.Uden,DiracTwidwell&CraigR.Allen,CoercedRegimes:ManagementChallengesintheAnthropocene,25ECOLOGY&SOC’Y,2020,at2–5;DavidG. Angeler & Craig R. Allen, Quantifying Resilience, 53 J.APPLIEDECOLOGY617,618(2017)(eroding an ecosystem’s resilience causes it to changemore easilywith thechangingclimate). 274. See generally Clifford et al., supra note 214, at 616 (discussing barriers totransformationadaptationstrategiesamongpubliclandmanagers).


climateadaptationpolicyhasgenerallynotpeeredintotheworldbe-yond2°C.275That“highemissions”scenarioisdescribedinmanyad-aptationreportsandstudies,butusuallyassomethingtobeavoided,notasaworld thatmightactuallyneed tobeplanned forandgov-erned.276Weareawareofnonational,state,orlocaladaptationplanthatbothbuildsouta4°Cscenarioandasks:Whatifstayingputforsubstantial segments of our population is not viable?277 Nor, it ap-pears,arecitiesthatwillbeabletostayputaskingwhathappenswhentheymustadapttosubstantialin-migrationfromtheothercities.278

Itmayverywellturnoutthatmanycommunitiesandsectorsareableto“future-proof”againsta2°Cworldandthatconservationman-agersareabletokeepecologicalresourcesfunctioning,albeitinnewforms, at 2°C—particularly in relatively wealthy Northern Hemi-sphere nations like the United States.279 It is tempting to believe,therefore, that if the planet warms beyond 2°C the Three Rs will 275. Seegenerally2018IPCC1.5°CReport,supranote23,at5(focusingona1.5°Cfuturebutmentioning2°Cimplications). 276. Seeid.(providinganoverviewofthepotentialimpactsandrisksassociatedwithclimatechange);2014U.S.ClimateImpactReport,supranote181,at25(discuss-inga“widerrangeofpotentialchangesinglobalaveragetemperatureinthelatestgen-erationofclimatemodelsimulations”). 277. Notably,however,in2014agroupofinterdisciplinaryresearchersfromAus-traliadidtaketheideaofa4°CfutureseriouslyenoughtoexaminewhatitwouldmeanforAustralia.SeeFOURDEGREESOFGLOBALWARMING:AUSTRALIAINAHOTWORLD,supranote68.Fromtheoppositeperspective,somePacificIslandnationsatsignificantriskofinundationarealreadynegotiatingwithcountriessuchasFiji,Australia,andNewZealandfornewhomelands.See,e.g.,LaurenceCaramel,BesiegedbytheRisingTidesofClimate Change, Kiribati Buys Land in Fiji, GUARDIAN (U.K.) (June 30, 2014),https://www.theguardian.com/environment/2014/jul/01/kiribati-climate-change-fiji-vanua-levu[https://perma.cc/4UM6-GCG5];HelenDempster&KaylyOber,NewZealand’s “Climate Refugee” Visas, DEV. POL’Y CTR.:DEVPOLICY BLOG (Jan. 31, 2020),https://devpolicy.org/new-zealands-climate-refugee-visas-lessons-for-the-rest-of-the-world-20200131 [https://perma.cc/NTB6-WLR5]. Thus, neither piece of ourquestiscompletelyunthinkableonitsown;thetrick,rather,istogetplacesliketheUnitedStatesthatarenotcurrentlyfacinganexistentialclimatechangethreattoseri-ouslyanticipatetheforcedretreatofa4°Cfuture. 278. Hauer,supranote192(emphasizingtheabsenceofscholarshipmodelinghowsealevelrise“isexpectedtoreshapetheUSpopulationdistribution”). 279. GivenourfocusongovernanceintheUnitedStates,wehavelargelysettoonesideforthisArticletheenormousadaptationinequitiesattheglobalscale,infavorofattemptingfirsttoaddressthefarsmaller—butneverthelessstillchallenging—issueofadaptation inequitywithinourowncountry.Ourperhapspresumptuoushope isthatifwecanbegintosuccessfullyaddress4°Cgovernancewithinanationthatshouldalreadyhavethecapacitytotakethemeasuresthatneedtobetaken,transferableles-sonswillemerge—perhapsespeciallyfromtheplanningroundtablethatweproposein Part IV.D—that can significantly aid equitable adaptation governance capacitybuildinginotherplaces.

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neverthelesscontinuetosupportincremental,insituadaptationandkeepexistinghumancommunitiesandconservationresourcesfunc-tioning.

Ifyoubuyintothat,readPartIIcarefullyagain.Howdowe“fu-ture-proof”againstthe4°Cscenario?

Theproblemisthat,asdescribedinPartII,the2°Cmark,asnastyasitis,islikelythethresholdatwhich,ifcrossed,climatechangetakesonnewandhighlyunmanageableproperties.280TheThreeRsascur-rentlymodeledandintegratedinto“future-proofing”policiesdonotconsiderrunawayinteractingpositivefeedbackloops,cascadeeffectsintheclimatesystem,andtheimpactstheywillhaveonsocial-ecolog-ical systems.281 As a result, there is growing concern that climatechangebeyond2°CwillswampthecapacitiesoftheThreeRsandthattransformational adaptation policies will need to operate at muchlarger scales, introduce novel strategies, and contemplate majorchangesandrelocations.282

Whileitistruethatindividualhumansinsmallgroupscansur-vive a wide range of climatological conditions, humans in largergroups—cities and counties—face real limits on their adaptability.Considera coastal city inFlorida: Itmaybe facing relentless stormsurgesandhurricanes, adrinkingwateraquifer contaminatedwithsaltwater, thereturnofdiseases likemalariaanddenguefever,andfrequentdangerousheatwaves.Resistanceandresiliencestrategieswouldhavetobeherculeantomanagerisksofthat level(andeventhose herculean efforts might fail), and locally managed retreat ispointlesswhenthereisnoplacelocallythatisoutofharm’sway. 280. SeeSteffenetal.,supranote8,at8254–56. 281. SeegenerallyGOVERNOR’SCOMM’NTOREBUILDTEX.,supranote268(discussingtheimplementationof“future-proofing”inTexas). 282. Katesetal.,supranote262,at7158(“Transformationaladaptationcould...bedrivenbysevereclimatechange[including]changesbeyondthelikelyrangeofcur-rentassessments,local‘hotspots’whereglobalchangeisamplified,ortippingpointsthatcauserapidclimatechangeimpactsincertainregionsorglobally”);seealsoKirstinDow,FransBerkhout&BenjaminL.Preston,LimitstoAdaptationtoClimateChange:ARiskApproach,5CURRENTOP.ENV’TSUSTAINABILITY384,385–86(2013)(“[Concepts]suchastippingpointsandkeyvulnerabilitiesimplythatclimatechangeimpactsmayoverwhelmsociety’s capacity to respond toavoidsignificantharm.”);AlarkSaxena,KristinQui&Stacy-AnnRobinson,Knowledge,AttitudesandPracticesofClimateAdap-tationActorsTowardsResilienceandTransformationina1.5°CWorld,80ENV’TSCI.&POL’Y152, 157–58 (2018); Giacomo Fedele, Camila I. Donatti, Celia A. Harvey, LeeHanna&DavidG.Hole,TransformativeAdaptationtoClimateChangeforSustainableSocial-Ecological Systems, 101ENV’TSCI.&POL’Y116, 116–20 (2019); Tyler Felgen-hauer,AddressingtheLimitstoAdaptationAcrossFourDamage-ResponseSystems,50ENV’TSCI.&POL’Y214,214–15(2015).


Inshort,adaptationinessenceisaformofriskmanagement.283Aworldat4°Cpresentsnotonlyradicallymoreintenseversionsoftherisksofa2°Cworld,butalsodifferentkindsofrisks.284Itfollowsthatanewkindofrisk-managementmode—onethatisbothanticipatoryandtransformative—willbeneeded.

C. REFRAMINGADAPTATIONFORREDESIGNTheThreeRswillalwaysbenecessary,buttheyarenotaimedat

managingthefundamentalredesignofbiophysicalsystemsthat4°Cwill impose.For thatkindof risk,ananticipatoryadaptationpolicymustmovefromincrementaltotransformativeandbepreparedinad-vancetoredesignsocialsystems.285Toputitanotherway,iftheeco-logicalsystemcomponentsofacomplexsocial-ecologicalsystemareundergoingdeepandunpreventableredesign,somustthesocialsys-temcomponentsandsomustthewayweapproachmanagementoftheecologicalresources.286Noamountoflocallygovernedresistance,resilience,ormanagedretreatcanavoidthatfundamentalpropertyofthe coevolving social and ecological components of large-scale sys-temsina4°Cworld.

So,whatdoesredesignmean?Firstandforemost,itmeanslettinggoofintact,insitu,andclose-to-normalastheunyieldinggoalsofad-aptation.AsdiscussedinPartII.C,evenwithintheUnitedStateswecan expect massive humanmigrations andmassive species migra-tions.287Wecanexpectrelocationofagriculturalcropand livestocklands.288Wecanexpectextensive,expensive infrastructureprojectstosupplyhousing,water,transportation,andotherneedsfornewandexpandinghumancommunities.289Wecanexpectdeepdisruptionsto

283. Felgenhauer,supranote282,at220(“[O]verlongtimeframesmitigationandadaptationarecomplementarytoolsofclimatechangeriskmanagement.”). 284. SeeFelgenhauer,supranote282,at215(“[A]4°Cchange[]willbringincreas-inglysevereimpactsthatmaysurpasssociety’sabilitytoadapt.”). 285. SeeKatesetal.,supranote262,at7159(“Insustainingtransformationalad-aptation,itseemslikelythatsupportivesocialcontexts,especiallyiftheyarecombinedwithincentives,andtheavailabilityofacceptableoptionsandresourcesforactionsarekeyenablingfactors.”). 286. Seeid. 287. SeeHauer,supranote192,at321(“[U]nmitigated[sealevelrise]isexpectedtoreshapetheUSpopulationdistribution.”). 288. See2014U.S.ClimateImpactReport,supranote181,at150–74. 289. Id.at89–90,114,131.

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insurance,finance,welfare,andothersocialandeconomicsystems.290Redesign is about designing and facilitating—perhaps even requir-ing—therelocationsandreconfigurationsnecessaryfortheseadapta-tionstosucceed.

Mostimportantly,however,wecanexpectthescaleofadaptationto shift its primary locus from local and state to regional and na-tional.291 It isplausible,whenplanningfora2°Cworld,foracityorstatetolookinward,askinghowitcanpromoteitscontinuedfunction-alities, includinggrowthanddevelopment, through theThreeRs.A4°Cworldvastlycomplicatesthatinward-lookingapproachbyintro-ducingtheprospectofsubstantialinter-regionalpopulationmigrationandall that comesalong,or leaves,with it.292 Similarly, rural areasmay face the complete loss, orwidespread introduction, of agricul-turallanduses,andconservationresourcemanagersmayfindacom-pleteabandonmentby,orsubstantialincreasein,recreationalusers.Inshort,localadaptationplanning,whetherforurbanorruralcom-munitiesorconservationresourcemanagers,willneedalso to lookoutwardtoplancoherentlyfortheinwardperspective.

Thisoutward-lookingdimensionof adaptationplanningneces-sarilyraisesthequestionofhowtoplanforthebetween.Thefateofanycityorregionwill,morethaneverbefore,dependonwhatishap-peninginothercitiesandregions,aspeople,agriculture,infrastruc-ture,water, energy, andother social-ecological systemcomponentsshift around the nation, in many cases over relatively short timeframes.Thebetween-lookingdimensioncapturestheinterconnected-nessofclimatechangeadaptationatthenationalscaleanditsinflu-enceonlocal,state,andregionalplanning.293

Ofcourse,therealreadyisanetworkthatconnectscitiesandre-gionswitheachother—thehighwaysandothertransportationinfra-structure, pipelines and transmission lines, product supply chains,bankingandfinancesystems,andothersystemsthatoperateatana-tionalscaletosupportlocalandregionalscales.However,ifsomere-gionsofthenationareliterallyshuttingdownandthepeopleleaving,

290. SeeCLIMATE-RELATEDMKT.RISKSUBCOMM.,MANAGINGCLIMATERISKINTHEU.S.FINANCIALSYSTEM25–27(2020);BeatriceCrona,CarlFolke&VictorGalaz,TheAnthro-poceneRealityofFinancialRisk,4ONEEARTH618,618–20(2021). 291. SeegenerallyKates,supranote262(“Insomeplaces ...vulnerabilitiesandrisksmaybesosizeablethattheycanbereducedonlybynovelordramaticallyen-largedadaptation.”). 292. SeegenerallyHauer,supranote192,at321(“[U]nmitigated[sealevelrise]isexpectedtoreshapetheUSpopulationdistribution.”). 293. SeeWarren,supranote185,at218–19.


destinedeitherforothercitiesorfornewlydevelopingareas,andyetmorepeoplearepressingtoenterthenation, theexisting intercon-nectionnetworkswillnotbeintherightconfigurationsorscaledtotherightlocalcapacities.Theywillneedtoberedesigned,aswellastechnologicallyimprovedandinnovated,todealwith4°Cconditions.Wearegoingtoneedtobuildnewandbetterbetweeninfrastructureandcapacity,andwewillneedittoenablemassivemovementofhu-mans,otherspecies,andeverythingthatgoeswiththem.

Tobesure,shocksofthismagnitudehavebefallencities inthepast,andtherehavebeenpulsesofsubstantialhumanmigration inournation,suchasinresponsetotheDustBowl.294Thereisoneim-portantdistinction,however,betweenthoseexperiencesandthere-designmodeofclimatechangeadaptation—weknowclimatechangeiscoming,thatitmaydragusnearoruptoa4°Cworld,andthatifitdoes,thekindandscaleofdisruptionswehaveoutlinedinPartIIwillbe inevitableand long-lasting.295Redesignwillnotbeoptional,norshoulditbeasurprisethatitisnecessary.Importantly,however,wealsohavetheabilitytoplanahead,aluxurythatshouldnotbesquan-dered.

ThisbringsustothequestiontowhichtheremainderofthisAr-ticleisdevoted:Whattodoaboutit?Moretothepoint,whydoany-thingaboutitnow?Afterall,itisnotasifa4°Cworldisjustaroundthecorner. Ifwecrossthe2°Cthresholdasaglobalaverage, itwilllikelybeseveraldecadesfromnowatthesoonest.296Whynotjustwaitandsee,lettingpeopledecidewiththeirfeetanddependingonnimblemarketsandastutepolicy-makerstotakecareoftheredesignthen?Andwhatcanbedoneaboutitnow,anyway,evenifwewantedto?Itwouldbeimpracticaltostartbuildingtheredesigninfrastructurebe-forepeopleneedit.

Thesearelegitimatequestions.PerhapsthisArticleshouldendhere, acting as testimony to future generations thatweknewwhatwascomingbutdecideditbesttoleaveittothemtofigureoutwhattodoaboutit.Thetwoofuschooseinsteadtoforgeahead.Specifically,weproceedfromheretoarguethatfuturegenerationsdeservebetterthanthat,andthatthepresentgenerationcaninfactdeliverbetter. 294. SeeinfraPartIV.A. 295. SeegenerallyWarren,supranote185,at227(addressingclimatechangeaf-fects“[c]onsideringthelargeimpactsintheagricultural,hydrologicalandecosystemsectorsexpectedina4°Cworld”). 296. See2018IPCC1.5°CReport,supranote23,at4–6(“Estimatedanthropogenicglobalwarmingiscurrentlyincreasingat0.2°C(likelybetween0.1°Cand0.3°C)perdecadeduetopastandongoingemissions.”).

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IV.GOVERNINGAT4°C:CONCEPTUALIZING,PLANNING,ANDIMPLEMENTINGREDESIGNADAPTATION

AsPartIIlaidoutindetail,PlanetEarthiswellonitswaytobeing4°C; indeed, despite the global pandemic, 2020 tied for the hottestyearonrecord(with2016),withglobalaveragetemperaturesreach-ing1.25°Chigherthaninpre-industrialtimes.297Australianresearch-ershavealreadyconcludedthat“thereiswidespreadagreementthatcurrentmitigationefforts . . .willleadtoglobalaveragewarmingof4°Cormorefrompre-industriallevelsbytheendofthiscentury...toaFourDegreeWorld.”298Thetwoofusarenotwillingtoriskthefu-ture of democratic governance to unwarranted optimism that theglobalcommunitywillsuccessfullysolvetheclimatechangemitiga-tionproblemintimetokeeptheglobalaverageincreaseintempera-turebelow2°C.Theissuethenbecomes:whatcantheUnitedStatesdonow to facilitate the survival of democratic governance in a4°Cworld?

TheUnitedStates(liketherestoftheworld’sgovernments)willincreasinglybedealingwithtransformationalchange.299Thisgovern-ancechallengewilllikelylastuntilsometimelongafteratmosphericconcentrationsofgreenhousegases finallystabilize.300Assuch,U.S.governance needs to move into—or at least be prepared to moveinto—theredesignmodeofclimatechangeadaptation.

Clearly,weshouldn’tbeseekingtoironoutallthenitty-grittyde-tailsofaredesignedUnitedStatesrightnow.Evensetting issuesofindividual libertytoonesideforthemoment(somethingwepreferfuturegovernancenottodoinreality),climatechangeimpactsremaintooprobabilisticandtoolongtermforexcessivelydetailedplans.

Nevertheless, probabilities are informative. As the discussionsabove emphasize, the most important consequence of transforma-tional 4°Cwarming for conceptualizing the governance of redesign

297. PaulVoosen,GlobalTemperaturesin2020TiedRecordHighs,371SCIENCE334,334(2021). 298. Christoff,supranote68. 299. SeegenerallyKatesetal.,supranote262(discussingtransformationaladap-tationneeds). 300. Weacknowledgethateventualclimatestabilizationisitselfanoptimisticas-sumptiononourpart.Withoutthatassumption,however,thisArticle’sentireexerciseispointless,becausetheplanetwilltransformradically,andperhapsunstoppably,asglobalwarming exceeds4°C, rendering the concept of nation statespotentially un-workable.


adaptation ismassivehumanmigrationwithin theUnitedStates.301Thisfocusincludesboththeattendantneedsofthatmigration(forex-ample, infrastructure, social reorganization, economic stabilization,foodandwatersecurity,healthcareadjustments)and itsattendantimpacts(forexample,competitionwithspeciesandecosystemsthatarealsomovingandtransforming,competitionwithagriculturalland,abandonedinfrastructureandtoxiccontamination,energyconsump-tion,andsocialandeconomicdisruption).302Moreover,whiletheex-actdetailsoffuturemigrationpatternscannotyetbepinpointedwithany precision, there is general consensus that the coasts and thesouthernpartsoftheUnitedStatesaremostatriskofbecomingun-livableandhencethatthecountry’smorenorthernandinteriorareasarelikelymigrationdestinations.303Finally,evenacknowledgingthatsurprises like pandemics will occur, climate change experts in theUnitedStatesalreadyhaveaworkinggraspofkeysystemicvulnera-bilitiesthatwarrantgovernanceattention—watersupply,foodsecu-rity,energyreliability,economicperturbations,environmentaldegra-dationandtransformation,andinequitabledistributionofandaccesstoalloftheabove.304

Thus, in conceptualizing a redesignmode of adaptation in theUnitedStates,wealreadyunderstand,atleastinbroadstrokes,whatgoalslawandgovernanceneedtofacilitate—asignificantshiftofhu-manpopulationsandtheirhousingandothersupportsystemsnorth-wardandinward,305whilesimultaneouslypreserving(oropeningup)lands for agriculture, species habitat, and migration corridors.306Preservationofafunctionaldemocracyatthesametimeimposestwoadditional requirements on how the United States governs towardthisgoal.First,governanceofthesechangesmustbelegitimate,sothatcitizensacceptandcomplywiththechangesandtheiraccompanyingsocial and economic dislocations. Second, governance of these

301. SeegenerallyWarren,supranote185,at228(discussingcross-regionalmi-grationresultingfrom4°Cwarmingconsequences). 302. Id.SeegenerallyFanetal.,supranote194(assessing“theregionaleconomicimpactsofclimate-change-inducedmigration”intheUnitedStates). 303. SeeHauer,supranote192,at323(“[M]anyinlandcommunitiescouldseetensofthousandsof[sea-levelrise]...migrants,andmanycoastalcommunitiescouldlosetensofthousandsofresidents.”). 304. Seegenerally2018IPCC1.5°CReport,supranote23. 305. SeeHauer,supranote192,at323(“[M]anyinlandcommunitiescouldseetensofthousandsof[sea-levelrise]...migrants,andmanycoastalcommunitiescouldlosetensofthousandsofresidents.”). 306. SeegenerallyWarren,supranote185,at228–32(discussingclimatechangeeffectsonmigration,land-use,andecosystems).

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changesmustbeequitable,ensuring thehealth, safety,and, ideally,prosperingoftheUnitedStates’mostvulnerablecommunitiesratherthansimplyexacerbatingexistinginequalities.307

That leaves two last questions. First, how should the UnitedStates finance this massive scale of social and economic transfor-mation?Second,who’sincharge?308Giventhescale,bothfinancialandgeographic,ofredesignadaptation,wepositthattheanswertobothquestionswilllieprimarilyinthefederalgovernment—although,asisalwaystrueinadaptationgovernance,governanceatalllevelswillre-mainnecessary,atleastthroughthefirstfewdecades.Adaptingto4°Cisbeyondthecapacityofanysinglestateorlocalgovernment.HumanmigrationwithintheUnitedStates,andtheaccompanyingreconfigu-rations of the nation’s economic, political, social, energy, food, andtransportationsystemswill requireanationalperspective,nationalcoordination,andanationalbudget.309Fortheseandotherreasons,the two of us find the governance challenges and solutions thatemergedthroughthecomplexoftheGreatDepression,DustBowl,andWorldWarIIramp-uphighlyinstructivehistoricalprecedentsforre-designadaptation,asdiscussedinmoredetailbelow. 307. Redesignadaptation isnothing ifnotdisruptive,butdisruptivenesscanbeharnessedtowardpositiveends,levelingtheplayingfieldamongcitizens.Asoneex-ample,foodrationingduringWorldWarII—agovernment-induceddisruptionofthefree market—actually benefitted poorer residents of both England and the UnitedStatesbyguaranteeingthemaccesstomeatandotherfoodstheypreviouslycouldnotafford.IselinTheien,FoodRationingDuringWorldWarTwo:ASpecialCaseofSustain-able Consumption?, ANTHROPOLOGYFOODS5,Sept. 2009, at ¶ 31;WendyMoore,Oh!WhataLovelyDiet,GUARDIAN(U.K.)(Jan.13,2001),https://www.theguardian.com/theobserver/2001/jan/14/life1.lifemagazine5 [https://perma.cc/974K-7E2B] (“Die-ticianshavelongarguedthatwartimerationingprovidedthehealthiestdiettheBritishpopulationhasevereaten,leadingtodramaticpost-warimprovementsinthenation’shealth.”). 308. ForacomprehensivesurveyofclimatechangeadaptationfederalismfocusedonthethreeRsofadaptation,seeRobertL.Glicksman,ClimateChangeAdaptation:ACollectiveActionPerspective onFederalismConsiderations, 40ENV’TL. 1159 (2010),providingaframeworkfordetermininghowtostructureapolicytofacilitateadapta-tiontoclimatechangethatassignsappropriaterolestoalllevelsofgovernment.SeealsoALEJANDROE.CAMACHO&ROBERTL.GLICKSMAN,REORGANIZINGGOVERNMENT:AFUNC-TIONALANDDIMENSIONALFRAMEWORK197–205(2019). 309. Notably,PresidentBiden’sClimateChangeExecutiveOrdercreatestheWhiteHouseOfficeofDomesticClimatePolicyandNationalClimateTaskForcetoservetheseleadershipand coordination roles and, although the focus is international relationsandnationalsecurity,ordersthedevelopmentofaclimatefinanceplan“toassistde-velopingcountriesinimplementingambitiousemissionsreductionmeasures,protect-ingcriticalecosystems,buildingresilienceagainsttheimpactsofclimatechange,andpromotingtheflowofcapitaltowardclimate-alignedinvestmentsandawayfromhigh-carboninvestments.”BIDENCLIMATECHANGEE.O.,supranote265,at§§102(f),202,203.


Whichtakesustooursecondpointaboutgovernancefor4°C.Justasprobabilistic scenarios arehelpful even though they cannotpre-ciselyinformusofthefuture,so,too,dopastgovernancechallengesandexperimentsintheUnitedStates—successfulorotherwise—pro-videhelpfultoolsthatcanincreasetheoddsoftheUnitedStates’re-designadaptationsucceeding,inallthesensesof“success”identifiedabove.Inpartbecauseofitssize,inpartbecauseofitsfederaliststruc-ture,andinpartbecauseofitsgeneralwillingnesstoembrace“pro-gress”andtechnologicalinnovationdespitetheirunintendedconse-quences,theUnitedStatespossessesagovernancetoolboxthatisbothwideanddeep,developedfromanongoingwillingnesstoexperimentwithgovernanceinstitutionsandmechanismswhilebothpreservingand evolving core societal values. One contemporary non-climatechangeexampleishowtopreserveandeffectuateFourthAmendmentprivacyinaworldof“smart”personalelectronicdevicesthataremorethancapableofspyingon,andrattingout,theirowners.310Adminis-trativelawisalargelytwentieth-centuryinventionthat(mostlysuc-cessfully)allowsafederaladministrativestatetobeshoehornedintoaConstitutionthatneverimaginedaneedfordailyregulatoryinter-actionsbetween the federal government and the inhabitants of theUnitedStates,andthisnewsubsetoflaweventuallyprovidedthoseresidentswithmultiplewaystokeeptabsontheirgovernment.311ItisneitheradistortionnoraninsulttoviewthehistoryofU.S.lawandgovernanceas250yearsofmakingitupaswego.

Inshort,theUnitedStatesisnotsteppingintoa4°Cgovernancefutureblindandunarmed.Norareitsgovernancesystemssoweldedtoset traditionsandunchangingrequirements thatadaptationgov-ernanceinaredesignmoderequiresfundamentalrevolution.ThesearebedrockgovernanceadvantagesthattheUnitedStatescancapital-izeupon.

Noneofwhich is tosay,however, that transitioningtogovern-ancefora4°Cnationwillbeeasy.TheremainderofthisPartexplores

310. E.g.,Carpenterv.UnitedStates,138S.Ct.2206,2217–18(2018)(holdingthatthe Fourth Amendment expectation of privacy applies to cell site location infor-mation);Rileyv.California,573U.S.373,386–401(2014)(holdingthatpoliceofficersneededawarranttosearchthroughdefendants’cell-phonedata);Katzv.UnitedStates,389U.S.347,353(1967)(holdingthatFBIagentsviolatedtheFourthAmendmentex-pectationofprivacywhentheyusedanelectroniclisteningdevicetolistentoaphoneboothconversation). 311. E.g.,AdministrativeProcedureAct,5U.S.C.§§551–559,701–706(governingthewaysinwhichfederaladministrativeagenciesmayissueregulationsandprovidingstandardsforjudicialreviewofagencyactions).

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whatthetwoofusconsiderthefourmostcriticalstartingpoints.Ourpublicandprivategovernanceinstitutionsandpolitymustrecognize:(1)thattransformativechangewilloccurindiversemodalitiessimul-taneously, complicating the governance of redesign adaptation; (2)that the various governance tools available require careful deploy-menttowardcoordinatedgoals;(3)thatsuchdeploymentwillrequireacoherent,anticipatorymodelfordesigningpolicystrategiesaroundthe intersectionsofchangemodeswithgovernancemodes;and(4)thatthereisaneednowtoactivelyplanforredesignadaptationanditsgovernance,includingidentifyingandthencarryingoutthemulti-disciplinaryresearchstillneededtoguidetheplanningeffortasitun-furls.

Criticaltoourconceptionhereisthatwhatispossiblepoliticallyalongthepathtoa4°Cworldwillchangebothprogressivelyandinpunctuatedburstsinresponsetonewrealities,aswasthecaseduringthe Great Depression,312 World War II,313 the Civil Rights Move-ment,314andCOVID-19.315Thus,thefactthatapotentialredesignad-aptationmeasurewouldbepoliticallyimpossibletoimplementnowshouldposenobarriertoitsfulltheoreticaldevelopmentnow,posi-tioningittobereadyforthemomentwhenitbecomesbothpoliticallyfeasibleanddesperatelyneeded(theformerlargelybecauseofthelat-ter).

A. DIFFERENTMODESOFCHANGE:APLANNINGTYPOLOGYFORREDESIGNPartIIpresentedablizzardofpredictionsaboutwhatcanbeex-

pected ina4°Cworld.Atamacroscale—albeitagrosslysimplified

312. SeegenerallyMyronP.Gutmann,DanielBrown,AngelaR.Cunningham,JamesDykes, Susan Hautaniemi Leonard, Jani Little, JeremyMikecz, PaulW. Rhode, SethSpielman&KennethM.Sylvester,Migrationinthe1930s:BeyondtheDustBowl,40SOC.SCI.HIST.707(2016)(mappingoutdifferentmigrationpatterns). 313. Social Changes During the War, DIGIT. HIST., https://www.digitalhistory.uh.edu/disp_textbook.cfm?smtID=2&psid=3493 [https://perma.cc/3QD2-WY5Q](tracking migration north to cities and west to California, and social changes forwomen,AfricanAmericans,andMexicanAmericans). 314. Civil Rights Movement, HISTORY (May 17, 2021), https://www.history.com/topics/black-history/civil-rights-movement [https://perma.cc/6BUY-5R8Y](explaining the changes brought by social movements and Civil Rights Acts of the1950sand1960s). 315. ManuelArias,SocialChangesinaPost-COVIDWorld—OpportunitiesandChal-lenges for PAOs, INT’LFED’NACCTS. (May 4, 2020), https://www.ifac.org/knowledge-gateway/developing-accountancy-profession/discussion/social-changes-post-covid-world-opportunities-and-challenges-paos [https://perma.cc/35X9-KA5U] (catalog-ingthedailysocialchangesmadeinthewakeoftheCOVID-19crisis).


one—the forces of change driving those specific conditions can besorted into three modes: baseline linear, nonlinear, and cascades.Thesemodesofchangereflectnotonly thedirecteffectsofclimatechange(hotterdays)butalsotheeffectsofadaptationtothem(build-ingseawalls).Weusehumanmigrationtoillustratethethreediffer-entchangemodes.Migration,afterall,isaformofadaptation,316andenvironmentalchangehaslongbeenadriverofhumanmigration.317

Thedecisiontomigrateorstayinthefaceofaclimate-inducedthreatsuchassealevelriseisinfluencedbyacomplexinteractionofeconomic,environmental,political,demographic,andsocialforces.318Inhisperceptiveassessmentofclimatechange-drivenhumanmigra-tion,geographerRobertMcLemanoutlinesaprogressionof thresh-olds:

Sixtypesofthresholdsinresponsetoclimatehazardsareidentified:(1)Ad-aptation becomes necessary; (2)Adaptation becomes ineffective; (3) Sub-stantivechangesinlanduse/livelihoodsbecomenecessary;(4)Insituadap-tationfails,migrationensues;(5)Migrationratesbecomenon-linear;and(6)Migrationratesceasetobenon-linear.319

Collectively,McLeman’ssixstagesembodythethreemodesofchangeresulting from climate-change-induced human migration that wewanttoemphasizehere.Baselinelinearchangeremainsthedominantmodeofmigrationinstages1–3ofhismodel,whichmightlooklittledifferentfromcurrentbaselinepopulationmovementpatternsintheUnitedStates,perhapswithoriginsanddestinationsshifted.Nonlin-earchangebeginsinMcLeman’sstage4andcontinuesintostage5,wheninsituadaptationfails,which is thestagethatrepresentsthestartofourrealconcernsfor4°Cadaptation.320Finally,inMcLeman’sstage6,cascadechangebecomesthedominantmode,duringwhichhumanmigrationsetsinmotionnumerousothersystemchanges.321ThisSectionexamineseachofthesethreechangemodesinturn.

316. Foranoverviewof lawandpolicyofhumanmigration inducedbyclimatechange, focusing on internationalmigration, seeMichelle Leighton,Population Dis-placement,Relocation,andMigration,inLAWOFADAPTATION,supranote25,at693–729. 317. E.g.,MyronP.Gutmann&VincenzoField,KatrinainHistoricalContext:Envi-ronmentandMigrationintheU.S.,31POPULATION&ENV’T3,5–6(2010)(lookingatde-mographicchangesasaresultofhurricanesintheU.S.). 318. SeeMathewE.Hauer,ElizabethFussell,ValerieMueller,MaxineBurkett,MaiaCall,KaliAbel,RobertMcLeman&DavidWrathall,Sea-LevelRiseandHumanMigra-tion,1NATUREREVS.EARTH&ENV’T28,29(2020). 319. Robert McLeman, Thresholds in Climate Migration, 39 POPULATION&ENV’T319,319(2018). 320. Id.at324. 321. Id.at325–26.

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1. BaselineLinearChangeManyofthedirecteffectsofclimatechange,suchassea-levelrise,

warming,and theshiftingof species ranges,will transpire in incre-mental,lineartrendsoverrelativelylongtimeframes.322Againstthisslow-movingbackground,somemeasureofhumanmigrationwillalsotakeplace at a baselinehistorical level. Peoplehave alwaysmovedaround in theUnited States—baselinemigration is nothing new.323Nevertheless, over long time frames, baselinepopulationmigrationandotherincremental,linearchangescanproducesignificantmacro-levelchange;forexample,therankingofU.S.citiesbypopulationsincethe1700sexhibitsamassivereshuffling.324Long-termeffectsofbase-line linearmigration, suchasmovement fromrural tourbanareas,thuseventuallycanpresentpolicychallengesfromaccumulatingef-fects,suchasincreasedcompetitionforemploymentandhousing.325

Intheshortterm,however,thechangesmayseemimperceptibleandnotwarrantinganyparticularpolicyconcern.Aspeopleandem-ployersbegintofactorclimatechangeintotheirlocationdecisions,itisentirelypossiblethatclimatechangehasalreadybecomeafactorinfluencingthiskindofdomesticU.S.baselinemigrationpattern,butinwaysthathavenotyetsurfacedatthemacro-scaleintopolicycon-cerns.326

2. NonlinearChangeClimatechangealreadyishavingeffectsthatdepartfrombase-

linelinearchangeandthat,overtime,willshifttheentireenvelopeofvariability for phenomena such as storm intensity.327 Similarly, 322. SeeAndrewC.Kemp&BenjaminP.Horton,ContributionofRelativeSea-LevelRise to Historical Hurricane Flooding in New York City, 28 J.Q.SCI. 537, 539 (2013)(chartinglinearsea-levelrisesince1775);seealsoSyun-IchiAkasofu,OnthePresentHaltingofGlobalWarming, 1CLIMATE 4,5 (2013) (indicatinganear-linear trend inglobalwarming);JohnP.McCarty,EcologicalConsequencesofRecentClimateChange,15CONSERVATIONBIOLOGY320,323(2001)(cataloguingeffectsofclimatechangeonvariousspecies). 323. SeeRavenMolloy,ChristopherL.Smith&AbigailWozniak,InternalMigrationintheUnitedStates,25J.ECON.PERSPS.173,174(2011)(chartinginterstatemigrationratesfrom1900to2010). 324. HistoricalMetropolitanPopulationsoftheUnitedStates:GraphofMetroAreaPopulation Rank Over Time, PEAKBAGGER.COM, https://www.peakbagger.com/pbgeog/histmetropop.aspx[https://perma.cc/CP69-NXPX]. 325. Leighton,supranote316,at693–94. 326. SeeMcLeman,supranote319,at326–27. 327. RobinKundisCraig, “Stationarity IsDead”—LongLiveTransformation: Five


populationmigration in theUnited States has never been purely abaselinelinearphenomenon;instead,episodesofamplified,purpose-fulmigrationhaveoccurredthroughoutthenation’shistory.Theset-tlementoftheAmericanWestthroughthe1800s,forexample,wasalongprocesswithmanycomplexcausesandeffects,layingthefoun-dationforlaternational-scalebaselinemigration.328Inthe1900s,themigrationofBlackAmericansfromtheSouthtotheNorth,Midwest,andWestshiftedoversixmillionpeoplebetween1915and1970.329Incontrasttobaselinemovesforanewjobortoretiretoawarmerclimate, broad social and economic forces induced these buildingwavesofmigration,creatinguneveneffectsacrossthenationalland-scape.Thesemigrationsalsoraisedpolicyissues.Asoneexample,theWestadoptedpriorappropriation for itswater law,participated inmassiveirrigationprojectswiththenewU.S.BureauofReclamationandthroughthemanyreclamationlawsCongressenacted,andcon-tinues tomovemassiveamountsofwater to service farmsandcit-ies.330

Sea-levelriseisexpectedtoproducethiskindofnonlinearmigra-tionwave,asalargeswathofthepopulation—coastalresidentsandemployers—facesacommonmotivationformoving.331Theimpactsofsea-levelrisemigrationalsowilllikelybeuneven,withsomemodelssuggestingthatmostrelocationswillbetonearbyinlandcounties,butalsowellintotheinteriorofthenation.332Asthesepulsesofmigrationbuild,policyissuesaresuretoariseasout-migrationthreatenseco-nomicandsocialprosperityinsomeareasandinfluxesofpopulation

PrinciplesforClimateChangeAdaptationLaw,34HARV.ENV’TL.REV.9,23–27(2010);P.C.D.Milly,JulioBetancourt,MalinFalkenmark,RobertM.Hirsch,ZbigniewW.Kun-dzewicz,DennisP.Lettenmaier&RonaldJ.Stouffer,StationarityIsDead:WhitherWa-terManagement?,319SCIENCE573,573–74(2008). 328. Foraliteraturesurvey,seeKimM.Gruenwald,MigrationandSettlementfromthe Atlantic to the Pacific, 1750-1890: A Survey of the Literature, NAT’LPARK SERV.,https://www.nps.gov/parkhistory/resedu/settlement.htm [https://perma.cc/CK8U-XJDX]. 329. ISABELWILKERSON,THEWARMTHOFOTHERSUNS:THEEPICSTORYOFAMERICA’SGREATMIGRATION8–16(2010). 330. Fortheclassicaccountofwaterdevelopmentandpoliciesinresponsetoset-tlementoftheAmericanWest,seegenerallyMARCREISNER,CADILLACDESERT:THEAMER-ICANWESTANDITSDISAPPEARINGWATER(1986). 331. SeeHauer,supranote192. 332. CalebRobinson,BistraDilkina&JuanMoreno-Cruz,ModelingMigrationPat-ternsintheUSAUnderSeaLevelRise,15PLOSONE,Jan.22,2020at8–11;DanielC.Vock,ClimateMigrantsAreon theMove:WhichCitiesNeed toPlan forPopulationBooms?,PLANNING (Jan. 1, 2021), https://www.planning.org/planning/2021/winter/climate-migrants-are-on-the-move[https://perma.cc/3QGG-NVL7].

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inotherregionsstresshousingsupply,employmentopportunity,andinfrastructurecapacity.333

3. CascadesChangeAsexplainedinPartII,risingtemperatureswillcauseecological

systemstocrosstippingpointsandexperiencesystemiccascadesofrapidchange.So,too,withsocialsystems.Suchtippingpoint“suddenonset”eventshavetriggeredmigrationcascadesinthepast,withclas-siccasesbeing theDustBowlmigrationof the1930sand thepost-KatrinarelocationoutoftheNewOrleansarea.334Bothofthesemi-gratory cascades occurred over short timeframes and had nationalpolicyconsequences.TheDustBowl,forexample,wastriggeredwhenfarmersintheGreatPlains“pushedbeyondthe‘unstableequilibrium’ofcropland-to-grassland,”anditledafterwardsto“agreatlyexpandedparticipationofgovernmentinlandmanagementandsoilconserva-tion.”335 Itwouldbenaïve to fail toanticipatesimilarsuddenonsetmigrationcascadesonthewaytoa4°Cfuture.

B. THETOOLBOX:ANIMPLEMENTATIONTYPOLOGYFORREDESIGNHavingsimplifiedadaptationintothreemodesofchange,wecon-

tinuewithourgrosssimplificationofanticipatoryadaptationinthissectionbyreducingadaptationgovernancetothreetop-levelmodes:laissez-faire,planningandprodding,andpreemptionandmandates.Wesuggesthowspecificexamplesofeachmodecouldguidepolicydesigninthe4°Cadaptationcontext.

1. Laissez-FaireFaithintheinvisiblehandofthemarketisneverfarfromthesur-

faceofcontemporaryAmericanpoliticsandpolicies,and,especiallyintheearlystages,thenormalforcesofsupplyanddemandmayinfactwork surprisinglywell topushandpull adaptation toa4°CUnitedStatesintherightdirections.Forexample,water-richareasincoolerclimatesmaystarttemptingwater-dependentindustries,likemanyofthose in Silicon Valley, to move, facilitating migration away from

333. Fanetal.,supranote194(exploringtheeffectsofpopulationredistributionduetoclimatechangeonhousing,wages,andlabordemandsintheUnitedStates). 334. McLeman,supranote319,at324–27;RobertA.McLeman,JulietteDupre,LeaBerrangFord,JamesFord,KonradGajewski&GregoryMarchildon,WhatWeLearnedfromtheDustBowl:LessonsinScience,Policy,andAdaptation,35POPULATION&ENV’T417,429,433–34(2014). 335. McLemanetal.,supranote334,at429.


water-constrained locations.336 Such municipal and state businessplansmight simultaneously encourage voluntarymigrants to reoc-cupycitiesthathavesignificantlydeclinedinpopulation,suchasDe-troit,potentially reducing theeventual infrastructurecostsof rede-signadaptation.EvidencethatwatermaybecomeadrivingforceofnewmarketsaswellasrelocationcomesfromCalifornia,whereawa-terfuturesmarkettoreducelocalrisksofdroughtbegantradinginDecember2020,337andfromincreasinginvestorinterestinmarketingColoradoRiverwater.338

Existingmarketswillalsorespondtoclimatechange,sendingsig-nalsthatlargerchangeisnear.Forexample,JohnR.Nolonassembledseveral case studiesof realestatemarketsacross theUnitedStateswhere“landuseclimatebubbles”haveburstorareatsignificantriskofbursting—that is,places“where landandbuildingvaluesarede-cliningduetoconsequencesassociatedwithclimatechange.”339Theclimaterisksinherentinrealestatemarketsarealsoanequityissue;forexample, it is lower-incomefamiliesthattendtoendupowningpropertiesatsignificantriskofflooding.340

Oneimportantplayerinclimate-affectedmarketsislikelytobethe private insurance industry. Insurance companies already haveconsiderable expertise at factoring climate change risk into their

336. StevenR. Strahler,HowChicago’sEnviableWater SupplyCouldLureFutureBusiness,CHI.BUS.(Sept.26,2019),https://www.chicagobusiness.com/crains-forum-water/how-chicagos-enviable-water-supply-could-lure-future-business [https://perma.cc/QS7C-EC9F];RachaelGleason&LauraFosmire,HowShouldGreatLakesCit-iesTapTheirWaterWealth?,GREATLAKESECHO(Aug.8,2011),https://greatlakesecho.org/2011/08/08/how-should-great-lakes-cities-tap-their-water-wealth [https://perma.cc/5SQY-4PCV]. 337. KimChipman,CaliforniaWaterFuturesBeginTradingAmidFearofScarcity,BLOOMBERGGREEN (Dec.7,2020),https://www.bloomberg.com/news/articles/2020-12-06/water-futures-to-start-trading-amid-growing-fears-of-scarcity [https://perma.cc/H8CL-MJ2H]. 338. BenRyderHowe,WallStreetEyesBillionsintheColorado’sWater,N.Y.TIMES(Jan. 3, 2021), https://www.nytimes.com/2021/01/03/business/colorado-river-water-rights.html[https://perma.cc/Q3AL-YWAF]. 339. JohnR.Nolon,LandUseandClimateChangeBubbles:Resilience,Retreat,andDueDiligence,39WM.&MARYENV’TL.&POL’YREV.321,323–24,325–27(2015). 340. Daniel Cusick,FloodRisks to Low-IncomeHomes toTriple by 2050, SCI.AM.(Dec. 1, 2020), https://www.scientificamerican.com/article/flood-risks-to-low-income-homes-to-triple-by-2050 [https://perma.cc/LS9B-8CGH] (detailing the fac-torsthatleavelower-incomerenters“trappedinpropertieswithrisingdisasterrisk”);seealsoJOHNR.NOLON,CHOOSINGTOSUCCEED:LANDUSELAW&CLIMATECONTROL1–18(2021)(expandingthediscussionofclimatebubblesanddescribinghowlowincomefamilies struggled to rebuild after storms while wealthier developers bought andflippeddamagedhomes).

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premiums,andtheyhavealreadysuedgovernmentsthathavemadetheirlossesworsebyfailingtobuildclimatechangeresilienceintolo-calinfrastructure.341Perhapsthemoreimportantadaptationroleforprivateinsurancecompanies,however,isasmarketsignalersofwheninsituadaptationisbecomingtooexpensivetobeprofitable,ashasoccurredboth inresponse to increasingwildfiredamage inCalifor-nia342 andhurricanedamage along theGulf.343 After the disastroushurricane seasonof2004–2005, companiesprovidinghomeownersinsurancelefttheFloridamarketindroves.344 Insurancecompaniesaresimilarlypoised tostop issuingwildfire insurance inCalifornia,discontinuinghundredsofthousandsofpoliciesin2019and2020.345Clearerpre-collapsewarningsthatinsituadaptationmaybebecom-inguntenableintheselocationsaredifficulttoconceive.

Privateinsurancemarketsignalswillbemosteffective,however,iffederalandstategovernmentsdonotintervene.Unfortunately,evi-dencetodateindicatesthatpoliticswillproduceexactlytheoppositeresult.Privateinsurancecompanieslongagogaveuponinsuringar-easofhighfloodrisk,whichiswhythefederalgovernmentsteppedinwiththeNationalFloodInsuranceProgram,whichisnowsignificantlyindebt.346 Similarly, insteadof listening to themarket, the State ofFloridasteppedintofillthe2005insurancevoid,andhomeowners’

341. AriPhillips,InLandmarkClassAction,FarmersInsuranceSuesLocalGovern-ments for Ignoring Climate Change, THINKPROGRESS (May 19, 2014), https://archive.thinkprogress.org/in-landmark-class-action-farmers-insurance-sues-local-governments-for-ignoring-climate-change-19c31eef042e [https://perma.cc/K9A7-SXN9]. 342. ChristopherFlavelle,CaliforniaBarsInsurersfromDroppingPoliciesinWild-fireAreas,N.Y.TIMES(Nov.5,2020),https://www.nytimes.com/2020/11/05/climate/california-wildfire-insurance.html[https://perma.cc/VD64-VX7Y]. 343. RebeccaMoybray,FiveYearsAfterHurricaneKatrina,HomeInsurancePricesRemainAstronomical,NOLA.COM(June25,2019),https://www.nola.com/news/busi-ness/article_a6b466ee-28c4-5096-a6bf-0baa7565bd98.html [https://perma.cc/83TV-N6VS]. 344. EdLeefeldt,WhyIsHomeownersInsuranceinFloridaSuchaDisaster?,FORBESADVISOR(Mar.26,2021),https://www.forbes.com/advisor/homeowners-insurance/why-is-homeowners-insurance-in-florida-such-a-disaster [https://perma.cc/4RZF-SRSJ]. 345. KhristopherJ.Brooks,CaliforniaInsurersareDroppingHomeownersThreat-ened by Wildfires, CBS NEWS (Oct. 21, 2020), https://www.cbsnews.com/news/california-wildfires-home-insurers-dropping-homeowners [https://perma.cc/8N6W-SERG]. 346. RobinKundisCraig,Harvey,Irma,andtheNFIP:Didthe2017HurricaneSeasonMattertoFloodInsuranceReauthorization?,40U.ARK.LITTLEROCKL.REV.481,484–92(2018).


insuranceinFloridaremainsa“disaster”fifteenyearslater.347Mostrecently,theCaliforniaLegislatureinstitutedaone-yearfreezeinNo-vember 2020, prohibiting insurance companies from discontinuingwildfirepolicies.348

Thus,insurancemarketsalsorevealthepublic’sandpoliticians’limitedappetitesfortrulylaissez-faireeconomicswhenmigrationhasbecome a financially rational adaptation response. Acknowledgingthatpoliticalreality,stateandfederalgovernmentscanbegintoactnowtolegallychangetheirresponsestoburstingrealestateclimatebubblesandinsurancecompanywithdrawals.Givenpublicdemandsfor government action when the market signals become focusedenough,governmentsshoulddirectthoseemergingsociallicensestoacttowardtheendsofequitableredesignadaptation.Forexample,ifgovernmentswanttohelpownersofpropertiesatriskfromclimatechange,theyshoulddosoontheunderstandingthatthe“insurance”payout is really the government’s purchase of the at-risk property(probablyatahigher-than-marketrate)thatenablestheformerprop-erty owner to move somewhere safer rather than to rebuild inplace.349Suchcreativeapproachestodisasterinsurancewouldbothfacilitatemigrationasitbecomesnecessaryandensurethatthena-tion’smostvulnerablecitizensarenotleftholdingtitletoworthlessrealestatewithnomeanstomove.

2. PlanningandProddingFew policy realms in the United States are left solely or even

largelytomarkets.Asoftmodeofgovernmentinterventioninvolvesplanningtoguidepublicpolicyandproddingtoguideprivateactorsintosteppinginlinewiththosepolicies.Planningandproddingwillplayimportantrolesinshapinganticipatoryadaptationfora4°Cna-tion.

a. PlanningIf thediscussions inPartsIIIandIVsuggestanything, it is that

redesignadaptationfora4°CUnitedStateswillrequiremassiveexer-cises inplanning.First, redesignadaptation requiresa spatial rear-rangementofbothpeopleandlandusesonanationalscale.Decisionsregardingwherepeoplecanliveandwherevariouskindsofhumanuses of space can occur has long been considered a proper

347. Leefeldt,supranote344. 348. Flavelle,supranote342. 349. Craig,supranote216.

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governmentalfunction,fromlanduseplanningandzoningonland350tomarine spatial planning in the ocean.351Marine spatial planningprovidesan improvedmodel for redesignadaptationover landuseplanningbecauseitalsotakesintoaccounttheneedsofthenaturalenvironment and ecosystems352—needs that should be very muchpartofredesignadaptation.

Second, redesign adaptation will require infrastructure up-grades, construction, and dismantling, with sequencing considera-tions and impacts—bothenvironmental and societal—thatwarrantsignificantplanning.Notably,thereisconsiderableagreementthattheUnitedStates’basicinfrastructurealreadywarrantsincreasedinvest-ment.Forexample,theAmericanSocietyofCivilEngineers’penulti-mateReportCardonAmerica’sInfrastructure,in2017,gavethena-tion’s infrastructure an overall grade of D plus;353 by 2021, it hadimprovedonlyslightlytoaCminus.354In2016,then-CandidateTrumppromised$1trilliontowardinfrastructuredevelopment,givingsomeindicationof theneeded investment just todealwithcurrent infra-structure issues.355 PresidentBiden’s January2021ClimateChangeExecutive Order also included a substantial commitment to

350. SeeVillageofEuclidv.AmblerRealtyCo.,272U.S.365,386–90,395(1926)(upholdingthevalidityoflocalgovernmentzoning).SeegenerallyFukuoAkimoto,TheBirthof‘LandUsePlanning’inAmericanUrbanPlanning,24PLAN.PERSPS.457(2009)(tracingthedevelopmentofurbanlanduseplanningintheUnitedStatesintoitsbroadacceptanceinthe1950sand1960s). 351. CRAIG,supranote255,at165–66;CharlesN.Ehler,MarineSpatialPlanning,inOFFSHOREENERGYANDMARINESPATIALPLANNING6–15(KatherineL.Yates&CoreyJ.A.Bradshaweds.,2018). 352. CRAIG,supranote255,at164–66. 353. 2017InfrastructureReportCard:AComprehensiveAssessmentofAmerica’sIn-frastructure, AM. SOC’Y CIV. ENG’RS 5 (2017), https://www.infrastructurereportcard.org/wp-content/uploads/2016/10/2017-Infrastructure-Report-Card.pdf[https://perma.cc/UMD4-KCRG].A“D”grademeansthat“[t]heinfrastructureisinpoortofairconditionandmostlybelowstandard,withmanyelementsapproachingtheendoftheirservicelife.Alargeportionofthesystemexhibitssignificantdeterioration.Conditionandcapacityareofseriousconcernwithstrongriskoffailure.”Id.at13;seealsoMakingtheGrade:WhatMakesaGrade?,AM.SOC’Y CIV. ENG’RS (2017), https://www.infrastructurereportcard.org/making-the-grade/what-makes-a-grade[https://perma.cc/FFB4-GAHM]. 354. 2021ReportCardforAmerica’sInfrastructure:America’sInfrastructureScoresa C-, AM. SOC’Y CIV. ENG’RS. (2021), https://infrastructurereportcard.org [https://perma.cc/8K76-FTQZ]. 355. JeffStein,Trump’s2016CampaignPledgesonInfrastructureHaveFallenShort,CreatingOpeningforBiden,WASH.POST(Oct.18,2020),https://www.washingtonpost.com/us-policy/2020/10/18/trump-biden-infrastructure-2020 [https://perma.cc/63HX-GL8F].


infrastructuredevelopment,356whichhassincebecomeoperativeintheBuildBackBetterAgenda357andespeciallyitsAmericanJobsAct,whichfocusesonincreasedinfrastructureforrenewableenergy,lead-ingtosignificantnegotiationsinCongressovertheaccompanyingin-frastructure authorization and finding legislation.358 The bipartisanappealof infrastructure investmentand itsbridgingofwhite collarandbluecollar,localandnational,urbanandrural,andeconomicandsecurityinterestsmakeinfrastructurealeadingcandidatebothtohealsocialandpolitical riftsand tokickstartadaptation toa4°CUnitedStates.

Third, redesign adaptationwill require increased and directedresearchinthe“hard,”“applied,”andsocialsciencesandinengineer-ingtobetterprojectclimatechangeimpactsacrosstheUnitedStates,human responses to those impacts, and ecosystem responses andneeds; to identify important tipping points and thresholds; and toboth identifyanddeveloptools for themultiple transitions—every-thingfromdrought-resistantcropsandrevisedagriculturalbusinessstrategies(forexample,atransitionawayfrommonocropping),tocli-mate-adjustedhealthcaretrainingandtreatments,tovariousformsofpredictionsoftware,tocolocationstrategiesforspecies,topsycho-logicalsupportsystems,toequity-enhancingpolicies.Theseresearchprogramswarrantplanningtoavoidadhocstudies,tocoordinatere-searchacrossdisciplines,andtoimproveinformationdissemination.

Finally,ascurrent infrastructureneedsamplydemonstrate,re-designadaptationrequiressignificantamountsofmoney—includingmoneyfortheplanningprocessitself.Thus,financialplanningmustalsobepartoftheadaptationtoolbox.

b. ProddingGovernmentcanalsoprodprivateinstitutionsintoplanningand

action.Asnoted,lefttoitsowndevices,theinsuranceindustryislikelytoprovidefairlystrongsignalsofwhenthetimehascomeforhumanstoabandoncertainareasofthecountry.359Governmentscouldthen

356. BIDENCLIMATECHANGEE.O.,supranote265,at§§212,213. 357. TheBuildBackBetterAgenda,WHITEHOUSE,https://www.whitehouse.gov/build-back-better[https://perma.cc/4HZH-CN2W]. 358. UpdatedFactSheet:BipartisanInfrastructureInvestmentandJobsAct,WHITEHOUSE (Aug. 2, 2021), https://www.whitehouse.gov/briefing-room/statements-releases/2021/08/02/updated-fact-sheet-bipartisan-infrastructure-investment-and-jobs-act[https://perma.cc/B53X-YRUM]. 359. See,e.g.,Leefeldt,supranote344(detailinghowmajorhomeinsurersscaledbackoperationsinFloridaafterthe2004–2005hurricaneseason).

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reinforcethesemarketsignalswithadditionalinducements.Thecon-version of government insurance subsidies to buyout programs al-readydiscussedisonesuchstrategy,combiningtheincentiveofgov-ernmentsupportwithaneventualmandatetoleave.

Thecloselyrelatedgovernmentprovisionofdisasterreliefisan-otherareaofaidthatgovernmentscouldadjusttobetterservethe4°Cadaptationenterprise.Intermsofpolitics,governmentsareunlikelyto resist calls for disaster reliefwhen the next hurricane, flood, orwildfire wipes out a community of uninsured residents and busi-nesses.Nor,givenourgoalofusingredesignadaptationasameansofincreasingsocialequity,dothetwoofusadvocatethatgovernmentssimplyignorethesedisasters.Rather,disasterrelief,likeallredesignadaptation,needstoshiftitsfocusawayfrominsituremedies—food,water, shelter, rebuilding—to redesign goals operating at a higherscale.Thus,disasterreliefshouldincreasinglytaketheformofrelo-catingdestroyedcommunitiesandshouldincluderetrainingandedu-cationsothatvictimscanthriveintheevolving4°Ceconomy.Thisre-formulated relief could simultaneously promote social equity byproviding more benefits to migrants who were already disadvan-taged.Fortunately,acceptanceofdifferentialaccesstogovernmentre-liefisdeeplyembeddedinU.S.lawandsociety360;thetrickwillbetoprevent theattachmentofstigma(forexample, “welfaremoms”) toqualificationforand/oracceptanceofthisrelief.361Inthisrespect,thecoronaviruspandemicmayprovideahelpfulexample.Whateverle-gitimatecriticismsmightbeleveledatCongress’sprovisionofcorona-virusreliefin2020,thatreliefwhenitarrivedbothincludeddifferen-tial access and remained relatively untainted by social stigma.362Governance for4°C redesign adaptation thusmight strive to figure

360. See,e.g.,AQuickGuidetoSNAPEligibilityandBenefits,CTR.ONBUDGET&POL’YPRIORITIES (Sep. 1, 2020), https://www.cbpp.org/research/food-assistance/a-quick-guide-to-snap-eligibility-and-benefits [https://perma.cc/MSX4-XV6H] (explainingtherequirementsforaccesstofoodassistance). 361. Stigmaassociatedwithgovernmentaidcandeterparticipationinthoseaidprograms,potentiallyexacerbatingtheproblemtheprogramwastryingtosolve.Jen-nifer Stuber& Karl Kronebusch, Stigma and Other Determinants of Participation inTANFandMedicaid,23J.POL’YANALYSIS&MGMT.509,509–10,526(2004). 362. Whileitisalwaysdifficulttoshowthatsomethingisnothappening,itisnota-blethatthemanyarticlesfocusingonCOVID-relatedstigmafocusonthediseaseitself,nottheacceptanceofgovernmentaid.E.g.,LauraK.Murray,KeriAlthoff,BethMcGinty&ElizabethStuart,COVID-19andStigma,JOHNSHOPKINSBLOOMBERGSCH.PUB.HEALTH(Jan. 13, 2021), https://publichealth.jhu.edu/2021/covid-19-and-stigma [https://perma.cc/BV9Z-Y2BV].Thelackofstigmaprobablyresultedinpartfromthesemi-au-tomaticnatureofsomeoftherelief,suchasstimuluschecks.


climatechangeasacommonenemythatneverthelesshurtssomepeo-plemorethanothersthroughnorealfaultoftheirown.

Ofcourse,otherclimate-relevantgovernmentsubsidiesandpay-mentprogramsalreadyexist.363Theseprogramscanchangeindivid-ualandbusinessbehavior364—although,admittedly,manyoperateasperverseincentives.365Cropsubsidiesareoneobviousexampleofex-istingsubsidiesthatgovernmentcouldretooltoincentivizeredesignadaptationfarbetter.Thesesubsidiesalreadycreateperverseincen-tives;366theworseningofwaterpollutionasaresultofincentivizingcropsforethanolfuelsisparticularlywellstudied.367Inredesignad-aptation, agricultural subsidies could serve much more useful—ifcompletelydifferent—goalsthantheycurrentlydo,suchasbyreduc-ingtheeconomicriskstofarmerswhoagreetofarmnewlandsasag-riculture shifts geographically, to experiment with new crops andseedstocksthatarebettersuitedtothechangingclimate,todiversifytheircropstoreducetherisksofcatastrophicfailureofmonocrops,andtoexperimentwithnewformsofintegratedpestmanagement(toreducepesticideuse) and crop combinations (to take advantage offunctional interactivity). Future Farm Bills might also incentivizefarmerstoinvestinwater-conservationtechnologiesforirrigatedag-ricultureinthe“right”locationswhilesimultaneouslyengaginginbestmanagement practices to improvewater quality, or simply financethattechnologicalandmanagementevolutionoutright.

Taxincentives,similarly,canhelpincentivizevoluntarycontribu-tions to redesign adaptation. Conservation easements provide one

363. See,e.g.,BIDENCLIMATECHANGEE.O.,supranote265,at§209(seekingtoendfederalfossilfuelsubsidies). 364. E.g., RichardW. Willson & Donald C. Shoup, Parking Subsidies and TravelChoices:AssessingtheEvidence,17TRANSPORTATION141,141,152–57(1990),(demon-stratingthatmoreemployersdrivetoworksolowhenemployerssubsidizetheirpark-ing);JohnS.Moot,Subsidies,ClimateChange,ElectricMarketsandtheFERC,35ENERGYL.J.345,346–47(2014)(arguingthatpricesuppressioncausedbysubsidiesleadstomoregeneratorretirements,which inturn leadstomoresubsidiesto“maintainre-sourceadequacy”). 365. Craig,supranote216,at216–20;AnthonyKammer,Cornography:PerverseIncentivesandtheUnitedStatesCornIndustry.8J.FOODL.&POL’Y1,2–4(2012). 366. Kammer,supranote365,at14–41. 367. Water Implications of Biofuels Production in the United States,NAT’LRSCH.COUNCIL 27–35, 45–60 (2008) https://doi.org/10.17226/12039 [https://perma.cc/K8PQ-KNEG];DavidPimentel,EthanolFuels:Energy,Balance,Economics,andEnviron-mentalImpactsareNegative,12NAT.RES.RSCH.127,130–31(2003);ReneeCho,Etha-nol’sImpactsonOurWaterResources,COLUM.CLIMATESCH.:STATEOFTHEPLANET(March21, 2011), https://news.climate.columbia.edu/2011/03/21/ethanol’s-impacts-on-our-water-resources[https://perma.cc/JUQ5-84ZS].

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modelof landuse incentivewithan importanttaxcomponent—alt-hough,asseveralscholarshavepointedout,themodelcouldbeim-provedtoallowforgradualevolutionandbettermonitoring.368Nev-ertheless,conservationeasementsmightberethoughttoincentivizethecreationofmigrationcorridorsforotherspeciesorthetransloca-tionofspeciesthatneedhumanassistancetofindnewhabitats.Mu-nicipalitieshavelongusedtaxbreaksandotherfinancialincentivestoinducebusinessestochoosetomovethere,369andstateandfederalgovernmentscouldconceivablyaddtheirowntaxinducementstoen-couragebusinessesandtheirancillarysupportsystemstobeginthemigrationtoredesign-desirablenewlocations.Forexample,atthebe-ginningof2020,theStateofVermontimplementedaNewWorkerIn-centiveProgramtoencourageyoungfamiliestomovetoVermontandwork for Vermont employers, building on a RemoteWorker GrantProgramthatpre-datedthepandemicandencouragedpeopletoliveinVermontwhileworkingforemployerselsewhere.370TheindividualeffortsofVermontandotherdestinationstatescouldresultincompe-tition for migrants—a competition that could become exceedinglyhelpfultoredesignadaptationwithabitofcoordinationandconsid-erablefundingfromthefederalgovernment.Thisincentivestructure,too,alreadyexistsinfederallaw,mostnotablyinthemultipleenvi-ronmental lawgrantprogramsandRevolvingStateLoanfundsthathelped the nation initially invest in sewage treatment infrastruc-ture,371 improve itsmunicipaldrinkingwatertreatmentcapacity,372andcleanupopendumps,373amongothernoteworthygoals.374

368. AdenaR.Rissman,JessicaOwley,M.RebeccaShaw&Barton(Buzz)Thomp-son,AdaptingConservationEasementstoClimateChange,8CONSERVATIONLETTERS68,68,70–74(2015);JessicaOwley,ConservationEasementsattheClimateChangeCross-roads,74L.&CONTEMP.PROBS.199,200,218–23(2011). 369. AndrewHanson& ShawnRohlin,DoLocation-BasedTax IncentivesAttractNewBusinessEstablishments?,51J.REG’LSCI.427,427–28(2011)(notingtheubiquityoftheseincentives);TimothyA.Dunn,Note,BusinessTaxIncentives:AModernViewUtilizingTiebout-HamiltonRationales,40TEX.J.BUS.L.235,237–240(2004)(“Taxin-centiveprogramsarenowthenorm,nottheexception,[inAmerica].”). 370. StateofVermont,RelocationIncentives,VT.DEP’TECON.DEVS.:THINKVERMONT,https://thinkvermont.com/relocation-incentives[https://perma.cc/7RGC-P3SM]. 371. CleanWaterAct,33U.S.C.§§1255,1256,1263a,1281–1301,1329,1381–1388. 372. Safe DrinkingWater Act, 42 U.S.C. §§ 300j to 300j-3d, 300j-12; see ArnallGolden&Gregory,GeorgiaReceivesFirstGrantUnderDrinkingWaterRevolvingLoanFund,8NO.10GA.ENV’TL.LETTER5(1997). 373. ResourceConservationandRecoveryAct,42U.S.C.§§6931,6947–6949. 374. Theseincludeairqualitymonitoringandimprovementgrants.SeeCleanAirAct,42U.S.C.§§7405,7616.


Afinalincentivethatmightwellbeworthrevivingislandgivea-ways,perhapsreconceivedinconjunctionwithinsurancebuyoutsaslandswaps.ThroughouttheUnitedStates’history,thefederalgovern-menthasgiftedlandtovariousgroupsofpeopleinpursuitofnationalgoals,suchasthe(largelyfailed)goalofprovidingnewlyfreedslaveswiththemeanstosupportthemselves375andthefarmoresuccessfulgoalofsettlingtheWestthroughHomesteadActs.376Thetwoofusarenotinanywaysuggestingthatallfederalpubliclandsbeconvertedtoprivate ownership.377 Nevertheless, some of these lands currentlyserve specific purposes that might become impossible as climatechangeworsens,evenasotherpubliclandsarebecomingcriticalha-vensandcorridorsforshiftingspeciesandecosystems.Humansarefar lessfussyabouttheirhabitatsthanmanyprotectedspecies,andevolvingecosystemsinNationalForestsorNationalGrasslandsmaylosetheircurrentnon-humaninhabitantsandnot,forwhateverrea-son,acquireothers. 375. MarkA.Graber,TheSecondFreedmen’sBureauBill’sConstitution,94TEX.L.REV.1361,1362(2016)(analyzingtheSecondFreedmen’sBureauBill).Thepromiseof“40acresandamule”actuallycamefromGeneralWilliamT.Sherman’sSpecialFieldOrder15 (Jan.16,1865),which setaside400,000acresof confiscatedConfederatelandsforthepurpose.SarahMcCammon,TheStoryBehind‘40AcresandaMule’,NPR:CODE SWITCH (Jan. 12, 2015), https://www.npr.org/sections/codeswitch/2015/01/12/376781165/the-story-behind-40-acres-and-a-mule [https://perma.cc/2NBM-7URB].However,afterPresidentLincoln’sassassination,PresidentJohnsonre-turnedmostofthelandtowhiteSoutherners.MaryWood,WhyLandRedistributiontoFormer Slaves Unraveled After the Civil War, U. VA. SCH. L. (Oct. 29, 2019),https://www.law.virginia.edu/news/201910/why-land-redistribution-former-slaves-unraveled-after-civil-war [https://perma.cc/DNW5-AEE2]. While the newlyfreed slaveswere eligible for land under both theHomesteadAct of 1862 and theSouthernHomesteadActof1866,theformeroperatedinpracticetofavorwhiteset-tlers,whilethelatterinvolvedlandsofpoorqualityandprovidedlittlesupportforthewould-be new farmers. See Homestead Act, HISTORY (Mar. 2, 2021), https://www.history.com/topics/american-civil-war/homestead-act [https://perma.cc/XEU2-SYTX](explaininghowmostofthelandreservedintheHomesteadActwenttospec-ulators,cattlemen,railroads,lumbermen,andminers);ThomasW.Mitchell,FromRe-constructiontoDeconstruction:UnderminingBlackLandownership,PoliticalIndepend-ence,andCommunityThroughPartitionSalesofTenanciesinCommon,95NW.U.L.REV.505,525–26(2001)(notingtheoverwhelmingpercentageofwhiteapplicantsforlandreservedundertheSouthernHomesteadActaswellasthepoorqualityoftheland). 376. ActofMay20,1862,12Stat.392;ActofMar.3,1891,26Stat.1097;ActofFeb.8,1908,35Stat.6;seealsoHannahL.Anderson,ThatSettlesIt:TheDebateandConsequencesoftheHomesteadActof1862,45HISTORYTCHR.117,118–20(2011)(not-ingthat10%oftheacreageoftheUnitedStateswassettledundertheHomesteadAct). 377. Notably,however,PresidentBideninJanuary2021didseektoenlistthefed-eralpubliclandsinclimatechangemitigationefforts,bothtoincreaserenewableen-ergyproductionandtoreducefossilfuelextraction.BIDENCLIMATECHANGEE.O.,supranote265,at§§207,208.

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Suggesting that the federal governmentmight consider giftinganyof theremainingpublic lands isvirtuallycertaintoraiseobjec-tions. Ifoutrightgiftsofpublic landsremainpolitically infeasible intheearlystagesofredesignadaptation,landswapsmaybeamorepal-atableapproach.Forexample,wehavesuggestedthatgovernmentsacquirecoastalproperties,andthesearelikelytoretainconsiderablevalueforrecreation,coastalhabitatandfisheries,aquaculture,trans-portation,and/ornationalsecurityevenastheylosetheircapacitiestosupporthumansettlement.Insteadofpurchasingthesepropertiesforcash,governmentsmightexchangesomeoftheirinlandpropertyinsteadorpurchase land in and around cities abandoned for otherreasons(Detroit,forexample)iftheyturnouttobeexcellentlocationsforfuturehumansettlement.Regardlessoftheexactincentivestruc-ture,however,government-ownedlandcanonceagainbecomeatooltoeffectuatepolicy,thistimeincentivizingsettlementintosaferareasofthecountryandnewagriculturalproductionareaswhile(throughswaps,atleast)simultaneouslyshiftingotherkindsofpublicusestodepopulated regions. Even the expanding deserts of the AmericanSouthwestmayretainpublicvalueasthesitesofsolaroralgaeenergyfarms.Thelargerpointisthat,aspartofredesignadaptation,Ameri-cansneedtobewillingtoreconceivethenation’slandusepatterns,includingintermsofpubliclands.

3. PreemptionandMandatesTheUnitedStatesisnostrangertomoreforcefulmodesofpublic

governanceintervention,includingmandatesandtop-downpreemp-tionfromfederalandstateauthorities.Althoughalmostalwayscon-troversial,itisdifficulttoimaginehowadaptationpolicyfora4°Cna-tion could succeed without ample use of strong forms of publicgovernanceintervention.Weoutlineseveralexamplesbelow.

a. CooperativeFederalismIfuncoordinatedfederalandstateaction isonepotentialrede-

signproblem—asithasbeenforthenation’sCOVID-19response—thecooperativefederalismembeddedinmultipleenvironmentalandnaturalresourcesstatutesprovidesonetestedmechanismforcoordi-natingthosegovernmentstowardacommongoal.Withinthesestat-utes, Congress generallyuses its constitutional authority (often theCommerceClause)toforceallfiftystatesintobaselineprotectionsof


environmentalqualityandhumanhealth,butitalsoleaveseachstatefreetoenactmorestringentprotections.378

CooperativefederalismforredesignadaptationmightrequirealittleheavierhandonCongress’spart,essentiallyrequiringthateverystate participate in redesign adaptationplanning andmanagement.For example, regarding outmigration states, Congressmight create(ordelegateauthoritytocreate)a“climatelivabilityindex”thatincor-poratesobjectivestandardsforassessingwhenmigrationoutofcer-tainareasis,progressively,rational,warranted,recommended,orre-quired. The federal government could then phase out key federalsupport mechanisms or phase in federal migration programs (likeland swap offers or insurance buyout structures) at each stage, orboth,whileleavingeachstatefreetocreateitsowninterimadaptationplansandprograms.Atthesametime,Congresscouldcreategrants,technology transfers, andplanning incentives toassist in-migrationstates inplanningandbuilding foranticipatedarrivalsofmigrants,whilestillleavingeachstateconsiderablefreedomtoplanitsownset-tlementpatterns.

b. PublicWorksProgramsIfthefederalgovernmentisgoingtoenduppayingforalotofthe

redesignadaptationinfrastructureanyway,itmightconsiderdoingsothrough apublicworksprogram that both createspaying jobs andprovides “future-proof” training to employees—that is, training inskillsthatarelikelytoremainemployablethroughoutthenation’sad-aptationcurve,likethebuildingandoperationofwindfarmsandsolarfarms,oragriculturaladaptationtraining.Themostobviousmodelforthis massive federal public works program is President FranklinDelanoRoosevelt’s“alphabetsoup”ofprogramsduringtheGreatDe-pression,379albeitwithsignificantlymorefocusedfinalaims.Notably,PresidentBidenhasalreadyincorporatedaCivilianClimateCorpsandother employment measures in his Climate Change Executive Or-der.380

Inanidealworld,theeconomicdislocationfromCOVID-19wouldprovidetheexcusetostartthisprocessmoreorlessimmediately,in

378. E.g.,CleanWaterAct,33U.S.C.§1370. 379. Foranoverviewoftheseprograms,seeTheNewDeal:FDR’sAlphabetSoup,USHISTORY.ORG, https://www.ushistory.org/us/49e.asp [https://perma.cc/TCG6-F8W4]. 380. BIDENCLIMATECHANGEE.O.,supranote265,at§§214–219.

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concertwithPresidentBiden’sinfrastructurebill.381Inparticular,theclimatechangeredesignalphabetsoupcouldstartwithafocusonin-frastructure.Firststepswouldbetothoroughlyassessexistinginfra-structurevulnerabilitiestoclimatechange,andthentostartupgrad-inginfrastructurecapacityintheareaslikelytosupportconcentratedhumansettlementinthefuture.Withabitmoreplanning,thefederalgovernmentcouldcreateprogramstostartbuildingtheinfrastructurenecessarytodecarbonizetheenergysystem,especially intheareasmostlikelytosupportfutureconcentrationsofhumanpopulation.Inaddition,thefederalgovernmentcouldbuildonitsexistingauthorityunder the Comprehensive Environmental Response, Compensation,andLiabilityAct(CERCLA)382andotherfederalpollutionstatutestoanticipatorilycleanuptoxichotspots,particularlyalongthecoasts,inplaceswherepeoplearelikelytoliveinthefuture,inareaswherefu-tureagricultureismostlikelytoflourish,andalonglikelyspeciesandecosystemmigrationroutes.Reducingthenation’stoxicburdenandexposureisagoodideaunderanycircumstancesandcouldwellhelptoavoidfutureadaptationdelays(forexample,agriculturecan’tshiftlocationsuntilthegroundiscleanenoughtogrowfood)andfutureenvironmental justice issues.NewprogramswithintheDepartmentofAgriculturecouldencouragefarmersanduniversitiestostartdiver-sifying agricultural production and experimenting at commercialscalewithclimate-resilientcrops,whileCongressshouldsimultane-ouslycontinueandprobablyintensifyitscurrentinterestinpromot-ing deepwater marine aquaculture,383 albeit in more explicitly cli-mate-readyandenvironmentallyfriendlydirections.

c. SocialSupportNetworksThemigrationscenarioweenvisionwillbedisruptive.Toavoid

worsening rather than improving existing inequities, governmentswillprobablyneedtoexpandsocialsupportnetworks,especiallydur-ing nonlinear and cascade migration events. Fully portable health

381. See,e.g.,JimTankersley,BidenDetails$2TrillionPlantoRebuildInfrastructureand Reshape the Economy, N.Y. TIMES (July 27, 2021), https://www.nytimes.com/2021/03/31/business/economy/biden-infrastructure-plan.html[https://perma.cc/L7ES-T2CD]. 382. 42U.S.C.§§9601–9675. 383. Q&AwithAquaculturePolicyExpertKatMontgomery,STRONGERAM.THROUGHSEAFOOD (Jan. 29, 2021), https://www.strongerthroughseafood.org/tipping-the-scales/2021/2/1/qampa-with-aquaculture-policy-expert-kat-montgomery[https://perma.cc/9A2W-J38G].


coveragewouldbebeneficial.Foodrationing,likeduringWorldWarII,384may be necessary to ensure distributional equity and at leastminimalfoodsecurity.Personalmigrationfinancingmaybothbecomeanewfinancialplanningspecialty,akintoretirementplanning,andrequiresubstantialgovernmentalunderwriting,suchasthroughsub-stantially subsidized loans, individual assistance programs, and/orsubsidizedmasspublictransportationtonewcommunities.Asnoted,retrainingsupportandadulteducationwillbehelpfulintransitioningdisplacedworkerstonewemploymentopportunities.

d. NationalEconomicPolicyThefederalgovernmentplayedakeyleadershiproleinpreparing

thenationforWorldWarIIintermsofbothpreparednessandactualconversionofthecountry’sindustrytoawartimeeconomy.385“Pre-paredness”described“thenationalprojecttoreadyforwarbyenlarg-ingthemilitary,strengtheningcertainalliessuchasGreatBritain,andaboveallconvertingAmerica’s industrialbasetoproducearmamentsandotherwarmaterielratherthanciviliangoods.”386Astwoexamples,merchantshipbuildingmobilizedtobuildthewartimefleet,and—al-beitwithmoreresistance—automobilecompaniesconvertedtoair-craftmanufacturing.387Theeconomicconversionwasmatched,more-over,byanewwartimeadministrativebureaucracy.388Anumberoffinancialinnovations,includingtaxesandwarbonds,alsocontributedtotheeffort.389

Redesignadaptationwillrequireasimilarscaleofeconomicandsocietalconversion,bothoftheWorldWarIItypeandgeographical.Therearecertainlyconstitutionalissuesthatwillariseifthegovern-mentstartsorderingpeopletomove,justastherewereconstitutionalchallengestothegovernment’sactionsinWorldWarII.390However,

384. Theien,supranote307. 385. ChristopherJ.Tassava,TheAmericanEconomyDuringWorldWarII,EH.NETENCYCLOPEDIA (Feb. 10, 2008), https://eh.net/encyclopedia/the-american-economy-during-world-war-ii[https://perma.cc/CM52-G8W5]. 386. Id.(emphasisadded). 387. Id. 388. Id. 389. Id. 390. Thesechallengestooknumerousforms,producingarangeofSupremeCourtdecisions.Someofthedecisionswereregrettableandhavesincebeenoverturned.E.g.,Korematsuv.UnitedStates,323U.S.214,217–19(1944)(upholdingtheconstitution-alityof Japanese internment),abrogatedbyTrumpv.Hawaii,138S.Ct.2392,2423

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there are also synergistic benefits for all involved in coordinatingmassrelocationsofindustriesthatwewanttopreserve,suchasrelo-catingSiliconValleytoDetroit.AsinWorldWarII,thisscaleofrede-signisbestcoordinatedfromthenationalgovernment.

C. ANTICIPATORYGOVERNANCE:BUILDINGFUTURESCENARIOSFORPOLICYSTRATEGYDESIGN

Perhaps thegreatestgovernancechallengeof redesignadapta-tionisthattherewillbenosinglemodeofchange—baseline,nonlin-ear,andcascadechangeswillbeoccurringsimultaneously.Norwillasinglemodeofgovernance—laissezfaire,planningandprodding,orpreemptionandmandates—beabletoeffectivelyengagethatmulti-modalchangedynamicacrossalltherelevantvariables.Anticipatoryadaptationpolicydesign,therefore,mustanticipatebothmulti-modalchangeandmulti-modalgovernance.Thequestioniswhichgovern-ancestrategytoaimatwhichmodeofchange.Forthatpurpose,ourvastlysimplifiedmodelsofthreemodesofchangeandthreemodesofgovernanceproduceathree-by-threematrixofintersectionpossibili-ties,asshown inTable1.Obviously, the4°Cgovernanceworldwillengagemorethanninepolicystrategies,buttheexerciseofconceptu-alizingevenasimplifiedmatrixofchange-governancemodeintersec-tionsdemonstratesthecoreprocessofanticipatorygovernance.

Anticipatorygovernancerefersbroadlytopoliciesfor“governinginthepresenttoadapttoorshapeuncertainfutures.”391Itisarela-tivelynewconcept,practicedprimarilyinplanningdisciplinesandinfuturesstudies,suchasscienceandtechnologyandsociologyofthefuture.392Anticipatory governancedependsheavilyon constructingmultipleplausiblefuturescenarios,embracesratherthandenieshighlevelsofuncertainty,andseeksadaptivepolicyimplementationtoolsto respond to changing conditions and knowledge over time.393Although some legal scholars have incorporated anticipatory

(2018).Othersremainunremarkable.See,e.g.,Lichterv.UnitedStates,334U.S.742,783–84(1948)(upholdingtheRenegotiatingAct,whichallowedtheU.S.governmenttorecoverexcessprofits fromwarcontractsagainstanondelegationdoctrinechal-lenge). 391. Muidermanetal.,supranote22,at1. 392. Id.at5–6. 393. Id.at3–10;seealso2021NASEMGLOBALCHANGERESEARCHREPORT,supranote168,at49–52(providingadescriptionofscenario-basedapproachestoclimatechangeresearch).


governanceintolawandpolicyforemergingtechnologies,394onlyafewhaveconnectedittoclimatechangeadaptationpolicy.395

Wedonothereattempttoplumbthedepthsofadaptivegovern-ancetheoryforeachoftheninepolicystrategydesignintersectionsinTable1,whichthetwoofusdonothavethecollectiveexpertisetoevenattempt. Instead,wepresentthisbroadoverviewtomakeourcentral point, developed in the next section, that beginning a data-drivenmulti-disciplinaryresearchandplanninginitiativeisthecriti-calfirststep.396Amodellikeours,orsomethinglikeit,canhelpfocussuchaninitiativebyestablishingrudimentaryscenariosuponwhichtoguideresearchandbuildmoredetailandrefinementtowardspol-icydesign.

Forexample,althoughlaissez-faire,market-basedresponsesmaybecapableofmanagingbaselinechangessuchasgradualincorpora-tionofnewbuildingmaterialsforgreaterinsulation,cascadechangeeventssuchasthecollapseofregionalwatersupplywilllikelyover-whelm that governancemode. Conversely,while the strong-arm offederalpreemptionmayberequiredtomanagetheeffectsofsuchacascadeevent,ensuring theorderlymovementofpeopleand infra-structuretoavoidreplicatinganotherDustBowl,itmaybeoverkilltouseittomanagebaselinechanges.

That, however, is a very high-level overview of a very simplemodel of the coming national governance challenges. Undoubtedly,moresophisticatedandsubtleblendsofpolicyinstrumentsarepossi-bleallowingformoreeffectiveandfine-tunedgovernanceresponsestoaspectrumofchangemodemixesoccurringatdifferentplacesandamongdifferentsubculturesoftheU.S.population.Asoneexample,looking just at humanmigration, the Gulf Coast (sea-level rise andstorms),Arizona(heatwaves),andGreatLakesstates(in-migration)couldbedominatedbycascadechangewhiletherestoftheWestisdominated by drought-driven nonlinear change and transitionalzonesplodalongatwhatstilllooksmostlylikebaselinechange.That 394. MillieM.Georgiadis&MargaretRyznar,RegulatingWhatHasYettoBeCre-ated:AnIntroduction,98TEX.L.REV.ONLINE71(2019);AlbertC.Lin,TechnologyAs-sessment 2.0: RevampingOurApproach to EmergingTechnologies, 76BROOK.L.REV.1309(2011). 395. Indeed,wecouldidentifyonlyonelawjournalarticlementioninganticipatorygovernance forclimatechangeadaptation inanysubstantivemanner,doingso inalargerandverycomprehensive surveyof anticipatorygovernance invariousurbanpolicysettings.SeeEdwardW.DeBarbieri,UrbanAnticipatoryGovernance,46FLA.ST.U.L.REV.75,102–06(2018). 396. Forwhatweconsidertobethemostthoughtfulargumentforapplyingantic-ipatorygovernancetoclimatechangeadaptation,seeVervoort&Gupta,supranote22.

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isonlyoneofhundredsofpossiblenationalscenariosthatanticipa-torygovernancecouldconsider.Farmoreinformationanddelibera-tionwillbeneededbeforegovernmentsatanylevelcanconfidentlycraftgovernanceinstrumentsthatassemblethebesttoolstorespondto the particular mix of change modalities they are most likely toface—as well as the governancemechanisms to evolve those assem-blagesasthemixofchangemodesevolves.Table1providesillustra-tionsofthekindsofhigh-levelchange-governancemodalassessmentsthatwillneedtooccur—assessmentsthatwillrequirefarmoredetailandrefinementbeforetheycanbetranslatedintoconcretelawandpolicyforanticipatoryadaptationgovernance.

Table 1. Change Mode and Governance Mode Intersections.

Laissez Faire Planning and Prodding

Preemption and Mandates

Baseline linear

Potentiallyeffec-tiveinmostcir-cumstancesbutwouldstillbene-fitfromcoordi-nationand/oragreedadapta-tiongoalssothatadhocpoliciesstillworktowardcommonends.

Servesaneduca-tionalfunctionandallowsforthebuildingoflegiti-macyandpublicconsensus;al-lowsequitymeasurestobeputinplaceearlytoincentivizethemostvulnerabletoimprovetheirpositions;allowsearlyadopterstoprovethead-vantages.

Probablyoverkilluntilthetrickleofchangesbuildupoverthelongerterm,suchastheeventualaban-donmentofsouthernandcoastalcities.

Nonlinear Inadequate,be-causeadhocandmarketpoliciesarelikelytopro-duceuncoordi-natedandevencontradictorylo-cal,state,orre-gionalresponses.

Necessarytoco-ordinateadapta-tionresponses,promoteequity,andminimizeconflicts;pre-servessomevol-untarinessinin-dividualresponse;pro-videsmassincen-tivestoinducein-dividualsandsectorstofollowpreferredadapta-tionpathways.

Increasinglynec-essaryinregionswherenonlinearchangeoccursonalargescale;pre-cautionarymeasurespro-videwarningoffutureadaptationrequirementsandincreasemotiva-tiontoengageearlywiththe“prods.”


Cascades Potentiallydisas-trous,becausechangesareoc-curringtoorap-idly,tootrans-formatively,andontoolargeascaleforadapta-tiontooccureq-uitablywithoutsignificantgov-ernmentinter-ventionandoversight.

Incentivesalignedwiththeoveralladapta-tionredesigncanstillhelptomoti-vateandincentiv-izecertaingroupsofindividualsandentitiestoengageinredesignadap-tationsemi-vol-untarily.

Necessary,be-causeatthispointtransforma-tivechangeishappeningsofastandonsuchalargescalethatfarmorecentral-izedcontrolisnecessarytoachieveredesignadaptationequi-tablyandrela-tivelypeacefully.

Twoimportantpointscanbederivedfromthissimplifiedexer-

cise.First,stateandlocalgovernmentsdeployingtheThreeRsofad-aptation policy—resist, resilience, and retreat—are unlikely toachievesufficientlycoordinatedorstrategicpoliciestomanageeventheseninechange-governancemodalintersections,especiallynonlin-earandcascadechangeforcesneedinglarge-scaleprescriptivegov-ernanceresponses.Redesignpolicieswillbeneeded,andanticipatoryredesigngovernanceneedstooccurwithinanationalpolicy frame-work.397Second,adaptationplanningatallgovernmentscalesmustexplicitlybuildnonlinearandcascadechangeintoadaptationplans.Behavingasifinsituclimateproofingisplausibleforeverylocality,andthatout-migrationandin-migrationandwhatfollowsfromthemwillnoteventuallytakeplaceatlargescales,isnotonlyunrealisticbutalsoirresponsible.Thenextsectionpresentsourproposalforhowtobegin.

D. ANINITIALSTEP:CREATINGANATIONALFORESIGHTSYSTEMFOR4°CADAPTATIONPLANNING

Evenifitwerecertainthataverageglobalwarmingwillreach4°Cbytheendofthiscentury,highdegreesofuncertaintyremainregard-ingwhatthatmeansfortheUnitedStates.PartIIoutlinedbroadbio-physicalpatternsofchange,398manyofwhichareexpectedtoleadto

397. SomeU.S.citieshaveusedtechniquesofanticipatorygovernanceinconnec-tionwithclimatechangeadaptationinfrastructureplanning,but,aswithalllocalcli-mateadaptationplans todate, the focushasbeenonusing theThreeRs for insituadaptation.SeeQuay,supranote22,at499–505(presentingcasestudiesofDenver,NewYork,andPhoenix). 398. SeesupraPartII.

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(orrequire)movementofdomesticpopulationandinfrastructure.Buthowmuchmovement,when,andtowhere?Whataretheimpactsonregionsexperiencingout-migrationandin-migration?Inshort,whatfuturedoweanticipateintheplanning?

Toaddressquestionslikethese,anticipatorygovernancebeginswithafuturescenariosanalysisdesignedtoinformflexibilityinplan-ningandgovernancetoallowadjustmenttomultiplepossiblereali-ties.399Anticipatorygovernanceacceptsthatsomeaspectsofthefu-turearenotknowableandbuildsthatrealityintoplanning.400Itis“amodeofdecision-makingthatperpetuallyscansthehorizon”inordertodevelopadata-driven“foresightsystem,” integratethat foresightintopolicy-making,andusefeedbacktoassessandadjustpolicyim-plementation.401 Importantly, the futurescenariosare“immediatelyusedtotestin-progressgovernmentpoliciesandplansinordertoen-surerobustnessinthefaceoffutureuncertainty.”402Thatiswheread-aptationgovernancefora4°Cnationmustbegin,andgovernancein-stitutions must get used to testing, learning, and adjusting as thewarmingunfolds.

AsdiscussedinPartIII,climatechangeadaptationplanninghasnotyetanticipatedtheneedforredesignwheninsituadaptationbe-comesuntenable,403buttheforcesofchangerequiringredesignwilltranspireatallscalesofplanning,fromlocaltointernational.Itisnotenoughtomodel the impactsofclimatechange;modelsofhowhu-mansrespondtothoseimpactsareneededtogainacompletepictureofhowtogovernredesignadaptation.Therefore,tosupportplanningandgovernancedesignatallofthesescales,weproposethatthefed-eralgovernmentconstructarobustnationalforesightsystemasthefirststepinanticipatorygovernanceforredesignadaptation.

Tobeeffective,suchanationalforesightsystemmustfullyem-braceafuture4°Cworld.Itmustbebroadlymulti-disciplinary,uniting 399. SilvaSerrao-Neuman,BenP.Harman&DarrylLowChoy,TheRoleofAntici-patoryGovernanceinLocalClimateAdaptation:ObservationsfromAustralia,28J.PLAN.PRAC.&RSCH.440,440(2013).Notably,evenjustattheretreatstage,“engaginginbold,long-termvisioningofadaptationfuturestohelpstakeholdersidentifywhichaspectsofthepresentshouldbepreservedandwhichshouldbeactivelychanged”isanim-portant activity.Mach& Siders, supra note 39, at 1296. It becomes evenmore im-portantattheredesignstage. 400. Quay,supranote22,at498. 401. StefanoMaffei,FrancescoLeoni&BeatriceVillari,Data-DrivenAnticipatoryGovernance.EmergingScenariosinDataforPolicyStudies,3POL’YDESIGN&PRAC.123,125(2020). 402. Vervoort&Gupta,supranote22,at108. 403. SeesupraPartIII.


climate scientists predicting climate impacts with anthropologistspredictinghumanresponseswith technologistsdeveloping thepre-dictiveanalyticstheyandtheotherrepresenteddisciplineswilluse.Togiveitgravitasandcredence,particularlygivenitwouldbedeliv-eringmostlyunpleasantnews,weproposethat theresearchbean-chored and directed through a new or expanded science-based re-searchbureauorservicewithinthefederalgovernment,akintotheU.S.Geological Survey, rather thanas amulti-agency task forcebe-tween existing agencies sending representatives to periodic meet-ings.404Theworkproductcannotbeasplashytask-forcereport,des-tined tocollectheadlines followedbydust,butratheracontinuous

404. AswewerecompletingthisArticle,theNationalAcademiesofScience,Engi-neering,andMedicinepublisheditsreportadvisingtheU.S.GlobalChangeResearchProgram(USGCRP)onhowtoshapeitsresearchprogramforthenexttenyears.2021NASEMGLOBALCHANGERESEARCHREPORT,supranote168.NASEM’sadvicemirrorsoursinseveralrespects.Forexample,NASEMadvisedthattheUSGCRP:

centertheirnextdecadalplan,andtheresultingprioritiesandactivities,us-inganintegrated[sic]riskframingapproach—thatis,onethatconsiderstheriskstohumanandnaturalsystemsposedbyclimatechange,andwhenap-propriate,climatechangetogetherwithotherglobalchanges.Thecommitteealsorecommendsfocusingonandcommunicatingthevulnerabilitiesandca-pacitiesofexposedsystemsandhowthesecouldshiftovertime,takingintoaccountthemultipleinterconnectionsofprojectedchanges,responses,andeffectsinhumanandnaturalsystems.

Id.at3.Thisemphasisonscenario-buildingissimilartowhatweadvocate.Moreover,NASEMemphasizedtheimportanceofinterdisciplinaryresearchandinsights,aswedo,noting,forexample,that“[a]dvancesinfundamentalandappliedEarthsystemsci-enceoverthenextdecadewillbesignificantlymoreusefulanduseablebyincreasedintegrationofnaturalandsocialsciences,improvingthebalanceamongphysicalcli-materesearch,ecosystemsresearch,andhumansystemsresearch.”Id.at5.WealsolargelyagreewithNASEM’sassessmentofadaptationresearchneeds:

Researchandcoordinationareneededtobetterunderstand:(1)theefficacyofadaptationpracticesimplementedatlocal,state,federal,andtribalscales,and applied by industry and other actors; (2)what additional efforts areneeded,todayandinthefuture;(3)currentandprojectedeconomicandso-cialconsequencesofpolicychoices;(4)theprocessesofdecision-makingtomanagesynergiesandtradeoffsovermultiplescales;and(5)synergiesandtrade-offsbetweendifferentadaptationandmitigationoptions.

Id.at6.Finally,weapplaudandsimilarlyemphasizeNASEM’sfocusonequityandso-cialjustice.Id.at7.

Nevertheless,NASEM’srecommendationsencompassashortertimehorizonthanoursandremainfocusedonstateandlocaladaptationefforts.Id.at2–3,7.Inaddition,byfederalstatute,theUSGCRPcoordinatestheresearchofothermission-drivenfed-eralagencies,id.at4–5,andhencedoesnotnecessarilyembraceeitherthesignificantinterdisciplinary and transdisciplinary insights we advocate nor the independencefromspecific resource-focusedgoals thatweconsidercritical to thenewagencyorthinktankthatweenvision.

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andrigorousdevelopmentanddisseminationofforesightforredesignadaptation.

Tosomeextent,ourproposalresurrectsthespiritbehindtheNa-tionalClimateServiceActof2009,whichwouldhaveestablishedabu-reauwithinNOAAtostudytheimpactsofclimatechangeand“supportdevelopmentofadaptationandresponseplansbyFederalagencies,State,local,andtribalgovernments,theprivatesector,andthepub-lic.”405However,ourproposaldiffersinthreekeyrespects.First,ourproposednewbureauwouldnotcreatemodelsofclimatechangeim-pacts.Itwouldbeaconsumerofthem,usingtheirfindingstoinformthedevelopmentoffuturescenariosofredesignadaptationthatincor-poratemodelsofhumanresponsestotheprojectedimpacts.Second,itsworkproductwouldendatscenariobuilding.Fromthere,otherpublicandprivateinstitutions,includingfederal,state,andlocalleg-islaturesandagenciesdevelopingandsupportingadaptationpolicies,wouldusethescenariostobegintobuildredesignadaptationpolicies.Third,thesolefocusofthenewbureauwouldbeonthe“beyond2°C”worldandtheneeditpresentsforredesignadaptation.Themeritsofaconsolidated,comprehensiveclimateserviceweredebatedincon-nectionwiththe2009proposal.406Wetakenopositiononthatissue;instead,ourproposal,inessence,istocreatea“beyond2°C”thinktankdevotedexclusivelytoanticipatingredesignadaptation.Inshort,thebureauwouldconsumeclimateimpactmodelsthatotherscientificre-searchentitiesdevelop,usingthemtoproducescience-basedredesignadaptationmodelsforusebypolicy-makingentities.407

Althoughourproposedforesightresearchbureauwouldbeasci-ence-oriented agency designed to produce scenario-based researchforusebypolicy-makers,toaccomplishitsmissionitsscopeofsciencewouldnecessarilyextendbeyondbiophysicalsciencestoincludeso-cial sciences such as demography, economics, sociology, and

405. NationalClimateServiceActof2009,H.R.2407,111thCong.(2009). 406. See U.S.GOV’TACCOUNTABILITYOFF.,GAO-10-113, CLIMATECHANGEADAPTION:STRATEGICFEDERALPLANNINGCOULDHELPGOVERNMENTOFFICIALSMAKEMOREINFORMEDDECISIONS3,51–3(2009). 407. Within the anticipatory governance literature, foresight initiatives are de-pictedalongaspectrumfromneutralexpert-drivenmodelingofplausiblefuturestomoredemocraticprocesseswithpublicparticipationinthedesignofdesiredfutures.SeeMuidermanetal.,supranote22.Givenhowradicallydifferentandunpleasantcon-ditionswillbebeyond2°C,webelieve it iscritical torelyonscience-based,expert-drivenmodelingofredesignadaptationscenariosandoptions.Thescenariosthisfore-sightinitiativeproducesovertimethencanbeusedtodevelopredesignadaptationpolicies,whichpresumablywillinvolvepublicparticipatoryprocesses.


psychology.408 Ideally, moreover, people with policy experiencewould alsobekeymembersof the research community, helping toshapethequestionsaskedandresearchdonesothatbothareimme-diatelypolicy-relevant.Itwillalsobeessentialthattheresearchiniti-ativeaskuncomfortablequestions,suchaswhichareasshouldbegintoprepareforsubstantialout-migration,andexplorescenariosthatwouldnotbetoleratedundercurrentpolicypreferences,suchasre-purposingpubliclandsfornewhumansettlements.409

Thisforesightsysteminitiativethuswouldaddressabroadarrayofquestions relevant to thenext step inanticipatorygovernance—namely,integratingtheforesightintopolicy-making.Representativeexamplesinclude:

• Whichregionsaremostlikelytoexperienceextremecondi-tionsofheat,saltwaterintrusion,storm,drought,flood,andotherclimateimpacts,andwhichtheleast?

• What are plausible social-technological-ecological systemcascade failure scenarios for areas experiencing themostextremeeffects?

o Whatdopopulationdemographicsandothersocio-economicconditionssuggestintermsofdemandforout-migrationopportunities?

o Where canmigrants go?Of areas experiencing theleasteffects,whicharemostamendabletoin-migra-tion,agriculturaldevelopment,migrationcorridorsand new habitat, energy production, and otherneededlanduses?

• Whatinfrastructurewillberequiredforhumanandagricul-turalrelocations?

• Howdothevariousscenariosholdupunderfinancialandothersocialsystemstresstesting?

• Whattechnologicaldevelopmentscaninfluenceflowsofmi-grationandinfrastructurerelocation?

408. Consistentwiththistheme,theNationalAcademyofScienceshasrecentlyad-vised that,whilecontinuedresearchonphysicsandbiogeochemistryof theclimatesystemisessential,climatechangeresearch“couldevolvetoapproachglobalchangeresearchdifferently inthecomingdecades,stressingthat the largestrisksexpectedwilllikelyarisefromtheinteractionsofmultiplesystems,suchasthefood-energy-wa-ternexusinthecontextofachangingclimate.Inaddition,thereportstressesthatef-fective responses will arise from integration of social and natural sciences.” 2021NASEMGlobalChangeResearchReport,supranote168. 409. SeeOwley,supranote44.

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• Whatarepotentialusesofabandonedareas?• Whatarepotentialusesoffederalpubliclandstoaccommo-

dateredesign,includingthepossibilityofusingthemasnewpopulationcenters?

• Whatareprojectedspeciesmigrations,andhow?Thislistisfarfromexhaustive.Indeed,theobjectiveoftheinitiativewould be to construct and continuously refine as close to “wholeworld”futurescenariosaspossible,asunpleasantastheymaybe.

Thereisnowaytoputlipstickonthe4°Cpig.Toanticipatehowtomanageredesignadaptationinthe“beyond2°C”world,itwillbeessentialforthenewresearchbureautoabandontheassumptionthatadaptationwilloccurprimarilyinsituthroughresist,resilience,andretreat strategies.410 Instead, it will need to build scenarios of na-tional-scalesocialandeconomicresponsesthatarenotconstrainedbyexistingpolicylimits,anditmustnotbepunishedfordoingso.

Whatpolicy-makersandthepublicdowiththescenariosisadif-ferentstory.Inthatrespect,althoughintheprevioussectionwesug-gestedbroadgovernanceimplicationsfordifferentchangemodes,411wegonofurtherinthisArticlethantourgecreationofthisnationalforesightsystem.Basedonwhatexpertsbelievetheyknownow,sum-marizedinPartII,asignificantlywarmingUnitedStateswillexperi-ence multiple disruptions at a variety of scales.412 Our nation canchoosetogointothatfutureblindandunprepared,oritcangointothatfuturewithforesightandadaptiveplanning,havingmademanyofthedifficultgovernancedecisionsinadvance.Giventhehighprob-abilitythatourfutureisa4°Cworld,thetwoofuschooseforesightandadaptiveplanningoverwingingit.

CONCLUSIONWe fully expect criticswill cast us as prophets of exaggerated

doomandgloom.However,wearesimplythebearersofthebadnewsscienceisproducing,413translatingitintoagovernancescenariothat

410. SeeQuay,supranote22,at499–505. 411. SeesupraPartIV.D. 412. SeesupraPartII. 413. Indeed,throughoutthewritingandeditingofthisArticle,theflowofbadnewsfromscienceneverceased.Notaweekwentbywithoutthepublicationofoneormorenewpeer-reviewedscientificstudies furthersupportingthe likelihoodofa“beyond2°Cworld”andfurtherdescribingitsradicalimpactsontheenvironmentandhumansociety.


seemsmorethanplausibleonceoneconsidershowdifferent,andhowhorrible,a4°Cworldlookscomparedtotheoneweliveintoday.

Othercriticsmightfullyacceptourdepictionofthe4°Cfutureandthegovernancechallengesitposes,butscoffattheideathatournationcouldactuallyputtogetheraplanandthenfollowitwhenconditionsbegintounravel.Theycouldpointtoournation’shandlingofthecoro-naviruspandemicasExhibit1.414Butthatmissesthepoint.Wearenotproposingaplan“forlater,”whentheworldmovespast2°Cofwarm-ing,butratherastartingactiontoputanticipatoryredesignadapta-tionmeasuresintoplace.Thetimetostartbuildingnationalredesignadaptationforesightisnow.

Wenowcomefullcircletowhatmotivatedthisproject—ourcon-cern thatclimatechangewill lead toa tippingpoint inournation’sgovernance.Recentexperiencejustifiesourconcern.

Americansoverestimatetheresilienceofourdemocracytoourperil. Notably, martial law—essentially, the conversion of a demo-craticregimetoanauthoritarianone—wasraisedasapossibilitydur-ingthecoronaviruspandemic415andcouldcertainlybecomeagovern-ancestrategytocopewitha4°Cworld.ThestormingoftheU.S.Capitol 414. PresidentGeorgeW.Bushaggressivelypursuedfederalpandemicplanningstartingin2005.SeePandemicFlu:PreparingandProtectingAgainstAvianInfluenza,WHITEHOUSEARCHIVES,https://georgewbush-whitehouse.archives.gov/infocus/pan-demicflu [https://perma.cc/9H5M-DQ6X].TheCenters forDiseaseControlandPre-vention(CDC)begandevelopingnationalinfluenzapandemicstrategyplans,includingrecommendingmeasuressuchasschoolclosingsandfacemasks.SeegenerallyCTRS.FORDISEASECONTROL,INTERIMPRE-PANDEMICPLANNINGGUIDANCE:COMMUNITYSTRATEGYFORPANDEMICINFLUENZAMITIGATIONINTHEUNITEDSTATES—EARLY,TARGETED,LAYEREDUSEOFNONPHARMACEUTICALINTERVENTIONS(2007).ACDCwebsitecollectingplanningdocumentsitandotherfederalagenciesdeveloped,somedatingto2005andothersasrecentas2017,wentdormantinJune2017.SeeNationalPandemicStrategy,CTRS.FORDISEASE CONTROL, https://www.cdc.gov/flu/pandemic-resources/national-strategy/index.html [https://perma.cc/YTU3-Z725] (showing last page review asJune15,2017).Foranengagingpoliticalhistory,seeDanDiamond,InsideAmerica’s2-Decade Failure to Prepare for Coronavirus, POLITICO (Apr. 11, 2020), https://www.politico.com/news/magazine/2020/04/11/america-two-decade-failure-prepare-coronavirus-179574[https://perma.cc/529J-3VX9]. 415. E.g.,SarahSicard,WillCoronavirusLeadtoMartialLaw?,MIL.TIMES(Mar.17,2020), https://www.militarytimes.com/news/your-military/2020/03/17/will-coronavirus-lead-to-martial-law [https://perma.cc/YP9G-HKX8]; False Claim: U.S.Coronavirus Response “Slowly Introducing” Martial Law, REUTERS (Apr. 14, 2020),https://www.reuters.com/article/uk-factcheck-coronavirus-introducing-mar/false-claim-u-s-coronavirus-response-slowly-introducing-martial-law-idUSKCN21W250[https://perma.cc/8Y8L-VMV7];JosephNunn,CanthePresidentDeclareMartialLawin Response to Coronavirus?, BRENNAN CTR. FOR JUST. (Apr. 16, 2020),https://www.brennancenter.org/our-work/analysis-opinion/can-president-declare-martial-law-response-coronavirus[https://perma.cc/W78B-KYBR].

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onJanuary6,2021,asCongresstalliedElectoralCollegevotes,pro-videsstarkevidencethatsocialandgovernancetippingpoints(“flashpoints”)existevenintheUnitedStates,allowingthepreviouslyun-thinkable tobecomereality inamatterofhours.416Magnifying thisdiscomfortingtruth,a4°CworldhasthepotentialtopushtheUnitedStates(andmuchof theworld)all thewaybackto tribalismas thebasicmodeofgovernance,417hintsofwhichalsosurfacedduringthepandemic.418

Scholarsandpoliticiansalikecoulddebateendlesslytheamountandvarietyofcultural,social,political,andeconomicfracturelinesin

416. Indeed,inmediaportrayals,thesiegeontheCapitolevidencedatleasttwokindsoftippingpoints.Thefirstwastheconversionofapeacefulprotestintoaviolentriot.E.g.,TomCostello,55ChargesSoFarfromCapitolRiot,OneSuspecthad11MolotovCocktails, NBCNEWS: JAN.7HIGHLIGHTS&ANALYSIS OFUNREST INWASH.,D.C. (Jan. 7,2021), https://www.nbcnews.com/politics/congress/live-blog/2021-01-06-congress-electoral-vote-count-n1253179/ncrd1253367 [https://perma.cc/HXB3-YP96].ThesecondwastheeffectthesiegehadonmanyTrumpsupporters,especiallyRepublican lawmakerswho had intended to protest the election results in severalstates.E.g.,AmyKlobuchar,SiegeofCapitola“TippingPoint”forThoseWhoHaveStoodby Trump, CBS NEWS (April 7, 2021), https://www.cbsnews.com/news/amy-klobuchar-reacts-to-siege-of-capitol-by-trump-supporters [https://perma.cc/M3PJ-SFYE]. 417. Forexample,concernisgrowingthat“intheeraofsocialmediaandpartisannewsoutlets,America’sdifferenceshavebecomedangerouslytribal,fueledbyacul-ture of outrage and taking offense.” StephenHawkins,Daniel Yudkin,Míriam Juan-Torres&TimDixon,HiddenTribes:AStudyofAmerica’sPolarizedLandscape,MOREINCOMMON 4 (2018), https://hiddentribes.us/media/qfpekz4g/hidden_tribes_report.pdf[https://perma.cc/7X4R-NAUP];seealsoGlobalWarming’sSixAmericas,YALEPRO-GRAM ON CLIMATE CHANGE COMMC’N, https://climatecommunica-tion.yale.edu/about/projects/global-warmings-six-americas[https://perma.cc/E5HM-BZS7];AmyChua&JedRubenfeld,TheThreatofTribalism,ATLANTIC (Oct. 2018), https://www.theatlantic.com/magazine/archive/2018/10/the-threat-of-tribalism/568342[https://perma.cc/ZT9V-9AFU].Seegener-allyCOLINWOODARD,AMERICANNATIONS:AHISTORYOFTHEELEVENRIVALREGIONALCUL-TURESOFNORTHAMERICA(2012). 418. Althoughallegiancestotribesmayhavehelpedussurviveupuntilthispointinhumanhistory,itmaybehavingtheexactoppositeeffecttoday.Asonecommenta-torobserved,“[t]hereseemstobeadifferenceinthewaywearerespondingtotheCOVID-19pandemicdependingonthetribe(friends,churchgroups,newsfeedsandTVnetworks)wehavealignedourselveswith.”ThomasPagano,TribalisminaTimeofCOVID-19, CITIZEN TIMES (April 16, 2020), https://www.citizen-times.com/story/opinion/2020/04/16/coronavirus-nc-tribalism-time-covid-19-opinion/5135096002[https://perma.cc/6G8C-PDNH];seealsoYuvalLevine,TribalismComesforPandemicScience, NEW ATLANTIS (June 5, 2020), https://www.thenewatlantis.com/publications/tribalism-comes-for-pandemic-science [https://perma.cc/SE3A-X5B6];SarahLahm,MidwestDispatch:RepublicanTribalismWon’tProtectUs fromthePan-demic, PROGRESSIVE (Nov. 17, 2020), https://progressive.org/dispatches/republican-tribalism-wont-protect-pandemic-lahm-201117[https://perma.cc/D7QJ-HBEH].


theUnitedStates(andothernations)419andtherelativeimportanceofeachtoclimatechangeadaptation.Themoreimportantpointhere,asthecoronaviruspandemicdeftlydemonstrated,420isthatdifferentregionsoftheUnitedStates“instinctively”reacttonewcrisesdiffer-ently.Climatechangewilllikelycomplicatethesealreadydivisivein-stinctsfurtherbyposingdifferentadaptationchallengesindifferentregions,someofwhicharemorefamiliartothosepopulations(suchasdroughtintheSouthwest)thanareothers(suchasmassmigration,collapseofbasic infrastructure likedrinkingwaterandsewagesys-tems,orwater-bornedisease).

Evenwellfunctioningdemocraticgovernancesystemswillneedtoadapt inordertomanagea4°Cworldeffectively,andtheUnitedStates’currentdefaulttoanextremeversionofindividualisticdemoc-racywillnotserveuswell.Ourdemocracyfocusesonpreservingin-dividualchoice,ensuringbroadparticipationingovernanceatalllev-els foralldecisions,andprotectionofprivateproperty,oftenattheexpenseofpublicvalues.421Thecostofsuchindividualismcanbe(andoftenhasbeen)a lackofcomprehensiveandcoordinatedeconomicandsocialplanningatalmostanyscale,fromcommunitiestothena-tionasawhole.422Indeed,responsestothecoronavirusepidemicintheUnitedStatesexposedmanyoftheweaknessesofthisgovernance

419. Forasweepingdiscussionof theperilousstateofdemocracy intheUnitedStates,seeSANFORDLEVINSON&JACKM.BALKIN,DEMOCRACYANDDYSFUNCTION(2019). 420. E.g.,TuckerDoherty,VictoriaGuida,BiancaQuilantan&GabrielleWanneh,Which States Had the Best Pandemic Response?, POLITICO (Oct. 15, 2020),https://www.politico.com/news/2020/10/14/best-state-responses-to-pandemic-429376[https://perma.cc/B5HZ-6G84]. 421. Constitutionaltakingsandstandinglimitationsonenvironmentalprotectionprovide twoobviousexamplesat the federal level.Fordiscussionof takings limita-tions,seegenerally,forexample,BeckettG.Cantley,EnvironmentalPreservationandtheFifthAmendment:TheUseandLimitsofConservationEasementsbyRegulatoryTak-ingandEminentDomain,20HASTINGSW.NW.J.ENV’TL.&POL’Y215(2014);ROBERTMELTZ,DWIGHTH.MARRIEN&RICHARDM.FRANK,THETAKINGSISSUE:CONSTITUTIONALLIM-ITSONLANDUSECONTROLANDENVIRONMENTALREGULATION (1999).Fordiscussionsofstanding limitations, seegenerally, forexample, JeffreyT.Hammons,Public InterestStandingand JudicialReviewofEnvironmentalMatters:AComparativeApproach,41COLUM.J.ENV’TL.515(2016);RobinKundisCraig,Removing“theCloakofaStandingInquiry”:PollutionRegulation,PublicHealth,andPrivateRiskintheInjury-in-FactAnal-ysis,29CARDOZOL.REV.149(2007);JeffreyW.Ring&AndrewF.Behrend,UsingPlain-tiffMotivation toLimit Standing:An InappropriateAttempt to Short-CircuitEnviron-mentalCitizenSuits,8J.ENV’TL.&LITIG.345(1994). 422. Notably,anation’scommitmenttoindividualismappearstoberelatedtoitssusceptibilitytodiseaseoutbreaks.SeeSergeMorand&BrunoA.Walther,Individual-isticValuesAreRelatedtoanIncreaseintheOutbreaksofInfectiousDiseasesandZoon-oticDiseases,SCI.REPS.,Mar.1,2018,at1.

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orientationatamomentwhenastrongnationalresponsetothecrisiswasrequired.423Multiplegovernmentsandlevelsofgovernmentis-sued uncoordinated and occasionally contradictory responses,424leadingtocostly“lossfromanarchy.”425 Individualsfelt freetomis-trust,deny,anddistortthescienceandtoignore“shelterinplace”or-dersandhealth-preservingbestpractices likewearinga facemask,leadingtonotableresurgencesininfectionratesinmanystatesaftertheMemorial Day, July 4, LaborDay, Thanksgiving, Christmas, andNewYearholidays.426Nationwide,therewasageneraldisregardforpublicwelfare,rangingfromaninabilityorunwillingnesstoinstitutecomprehensiveCOVIDtestingprograms427tolimitedandonlyshort-termsocialsupportmeasuresthatincreasedthepressurestogobacktowork.428

Nothing in thisexperience, fueledbyan increasinglypoliticallysectariannation,429bodeswellforenvisioninghowanindividualistic 423. See George Packer,We Are Living in a Failed State,ATLANTIC (June 2020),https://www.theatlantic.com/magazine/archive/2020/06/underlying-conditions/610261 [https://perma.cc/G4H9-AKE7] (“With no national plan—no coherent in-structions at all—families, schools, and offices were left to decide on their ownwhethertoshutdownandtakeshelter.”);seealsoRebeccaL.Haffajee&MichelleM.Mello,ThinkingGlobally,ActingLocally—TheU.S.ResponsetoCovid-19,N.ENG.J.MED.,May28,2020,at1. 424. James Brown, America’s Coronavirus Response ‘Completely Uncoordinated’,U.S. STUDY CTR. (Apr. 2, 2020), https://www.ussc.edu.au/analysis/americas-coronavirus-response-completely-uncoordinated[https://perma.cc/M8R9-23DK]. 425. DavidHoltz,MichaelZhao,SethG.Benzell,CathyY.Cao,M.AminRahimian,JeremyYang,JenniferAllen,AvinashCollis,AlexMoehring,TaraSowrirajan,DipayanGhosh,YunhaoZhang,ParamveerS.Dhillone,ChristosNicolaides,DeanEckles&SinanAral,InterdependenceandtheCostofUncoordinatedResponsestoCOVID-19,117PROC.NAT’LACAD.SCI.19837,19837(2020).(“Theseresultssuggestasubstantialcostofun-coordinatedgovernmentresponsestoCOVID-19whenpeople,ideas,andmediamoveacrossborders.”). 426. See,e.g.,DakinAndone,HealthOfficialsBraceforaSurgeinUSCOVID-19CasesAftertheHolidays,CNN(Dec.26,2020),https://www.cnn.com/2020/12/26/health/us-coronavirus-saturday/index.html[https://perma.cc/D8VE-EAND]. 427. Id. (describingmissteps theCDC took indevelopinga testingprotocol andequipment). 428. AndrewStettner,EllieKaverman,AmandaNovello&MosheMarvit,FightingfortheRighttoaSafeReturntoWorkDuringtheCOVID-19Pandemic,CENTURYFOUND.(July 29, 2020), https://tcf.org/content/report/fighting-right-safe-return-work-covid-19-pandemic [https://perma.cc/F5VE-LPY4] (describing decisions by somestatestoreopeneconomicactivity). 429. EliJ.Finkel,ChristopherA.Bail,MinaCikara,PeterH.Ditto,ShantoIyengar,SamaraKlar,LillianaMason,MaryC.Mcgrath,BrendanNyhan,DavidG.Rand,LindaJ.Skitka, Joshua A. Tucker, Jay J. Van Bavel, Cynthia S.Wang & James N. Druckman,


democracywouldmanagelifeat4°C.Tobesure,itwilltakealongtimetoreach4°C,butthetippingpointsalongthewaywillleadtocascadesofchangeinsocial-ecologicalsystemsthatwillrivalthepandemicintheirflash-pointdisruptioneffects.Ifwehaddevelopedarobustna-tional foresight system for pandemics and followed through withplanningandimplementation,theexperiencemighthavebeenmuchdifferent.Knowingthat,wecandobettertopreparethenationforthepathto4°C.Thefirststepisgainingforesight.

PoliticalSectarianisminAmerica,370SCIENCE533,533–34(2020)(notingthatAmer-icansectarianismisincreasingatthefastestrateamongninewesterndemocracies).

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