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BY 4.0 license Open Access Published by De Gruyter Open Access October 28, 2009

Additive Damages, Fat-Tailed Climate Dynamics, and Uncertain Discounting

Martin L. Weitzman
From the journal Economics


This paper in applied theory argues that there is a loose chain of reasoning connecting the following three basic links in the economics of climate change: 1) additive disutility damages may be appropriate for analyzing some impacts of global warming; 2) an uncertain feedback-forcing coefficient, which might be near one with infinitesimal probability, can cause the distribution of the future time trajectory of global temperatures to have fat tails and a high variance; 3) when high-variance additive damages are discounted at an uncertain rate of pure time preference, which might be near zero with infinitesimal probability, it can make expected present discounted disutility very large. Some possible implications for welfare analysis and climate-change policy are briefly noted.

JEL Classification: O54


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Published Online: 2009-10-28
Published in Print: 2009-12-01

© 2009 Martin L. Weitzman, published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

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