Equitable Provision of Long-Term Public GoodsThe role of Negotiation Mandates

First draft: January 2001 This version: June 17, 2003 The authors are grateful to Roger Guesnerie, Tarik Tazdait, and the participants of a seminar on climate change economics at College de France in April 2002 for helpful comments on an earlier version of this manuscript. Any remaining error are the authors'. The views expressed in this paper do not necessarily represent the views of the World Bank, its executive directors, or the countries they represent.We examine the international distribution of expenditures for the provision ofa global, long-term and uncertain public goods from the point of view of abenevolent planner. Even assuming a "no-redistribution" constraint, first periodexpenditures are in general progressive with income, and independent both fromtotal level of action, and from future distribution of damages. However, instatus-quo mandates-where current negotiating powers shape both present andfuture allocation-future distributions of efforts are very unequal, andagreement, if any, is at high risk of instability. An adaptative mandate provesnecessary to provide an acceptable solution