9309610 Heal This research will further develop the issue raised in the investigator's paper "International Negotiations on Emission Control." That paper studies the incentives that countries have to join and to remain in international agreements on the abatement of global pollution. It develops the concept of a critical abatement coalition, one with the property that all members are net gainers from membership. There will be a smallest critical coalition because of certain threshold effects. One of the earlier paper's results is to identify as very important in the stability of coalitions the extent of cross effects on net benefits between countries that join a coalition. These will be referred to as "reinforcement mechanisms." In particular, the stability of agreements is increased by the extent to which abatement by country i increases the marginal net benefit of country j from abatement by j. This research will identify and model ways in which the introduction of abatement policies by one country could reduce the abatement costs of another and provide reinforcement mechanisms. The research will then take two initial steps towards empirically implementing the ideas of critical coalitions and reinforcement mechanisms. One will be a preliminary attempt to identify alternative minimum critical coalitions for the avoidance of global climate change. The second will be a preliminary identification of reinforcement mechanisms. ***
