Christian Traeger (lead) David Anthoff, Karen Fisher-Vanden, Chris Forest, Klaus Keller, Robert Lempert, Nancy Tuana

The precautionary principle is the most common guidance to decision-making under uncertainty in sustainability analysis. While intuitively appealing, this principle raises decision-theoretical and ethical concerns. We build on a normatively desirable, axiomatic framework formalizing important concerns of the precautionary principle that lack in the economic standard model: we include intrinsic risk attitude and distinguish between the evaluation of well-known risks and hard-to-quantify uncertainty (ambiguity). Our applications analyze various climate uncertainties and their implications for current climate policy.