Dumas, P.Hourcade, J. C.Fabert, B. Perrissin2012-03-192012-03-192010-07-01https://hdl.handle.net/10986/3876This paper confronts the wide political support for the 2C objective of global increase in temperature, reaffirmed in Copenhagen, with the consistent set of hypotheses on which it relies. It explains why neither an almost zero pure time preference nor concerns about catastrophic damages in case of uncontrolled global warming are prerequisites for policy decisions preserving the possibility of meeting a 2C target. It rests on an optimal stochastic control model balancing the costs and benefits of climate policies resolved sequentially in order to account for the arrival of new information (the RESPONSE model). This model describes the optimal abatement pathways for 2,304 worldviews, combining hypotheses about growth rates, baseline emissions, abatement costs, pure time preference, damages, and climate sensitivity. It shows that 26 percent of the worldviews selecting the 2C target are not characterized by one of the extreme assumptions about pure time preference or climate change damages.CC BY 3.0 IGOABATEMENT COSTABATEMENT COSTSABATEMENT POLICIESANTHROPOGENIC GREENHOUSEANTHROPOGENIC GREENHOUSE EFFECTASSESSMENT OF CLIMATE CHANGEASSESSMENT OF CLIMATE CHANGE IMPACTSATMOSPHEREATMOSPHERIC CONCENTRATIONATMOSPHERIC CONCENTRATIONSBASELINE EMISSIONSBIOSPHERECAPITAL STOCKSCAPITAL TURNOVERCARBONCARBON CYCLECARBON DYNAMICSCARBON EMISSIONSCARBON FLOWSCARBON INTENSITYCARBON PRICESCARBON SAVING TECHNOLOGIESCARBON-CYCLE MODELCATASTROPHIC CLIMATE CHANGECATASTROPHIC DAMAGESCLIMATECLIMATE CHANGECLIMATE CHANGE DAMAGECLIMATE CHANGE DAMAGESCLIMATE CHANGE IMPACTSCLIMATE DAMAGECLIMATE MITIGATIONCLIMATE MODELCLIMATE MODELSCLIMATE POLICIESCLIMATE SCENARIOSCLIMATE SENSITIVITYCLIMATE SYSTEMCLIMATE VARIABILITYCLIMATIC CHANGECO2COST OF ABATEMENTCOST OF CLIMATE CHANGECOST-BENEFITCOST-BENEFIT ANALYSISCOST-BENEFIT FRAMEWORKDEEP OCEANDEFORESTATIONDEVELOPMENT ECONOMICSDISCOUNT FACTORDISCOUNT RATEDISCOUNT RATESECONOMIC GROWTHECONOMIC MODELSECONOMICS OF CLIMATE CHANGEECOSYSTEMEMISSIONEMISSION ABATEMENTEMISSIONS ABATEMENTEMISSIONS PATHWAYSENVIRONMENTAL RISKSEXTREME VALUESGHGGHGSGLOBAL MEAN TEMPERATUREGLOBAL MEAN TEMPERATURE VARIATIONGLOBAL TEMPERATUREGLOBAL WARMINGIMPACTS OF CLIMATE CHANGEINCREASE IN TEMPERATUREINTEREST RATEINTERGOVERNMENTAL PANEL ON CLIMATE CHANGEINTERNATIONAL CLIMATE NEGOTIATIONSIPCCLAND-USE CHANGELEVEL OF EMISSIONSMONETARY VALUESPROBABILITY DISTRIBUTIONRADIATIVE FORCINGRAPID CLIMATE CHANGERESERVOIRSSCENARIOSSOCIAL DIMENSIONS OF CLIMATE CHANGESURFACE OCEANTEMPERATURETEMPERATURE INCREASETEMPERATURE RANGETEMPERATURE RISESTEMPERATURE THRESHOLDSTEMPERATURESUTILITY FUNCTIONVALUE OF CLIMATE SENSITIVITYWELFARE FUNCTIONWorld Bank10.1596/1813-9450-5392