If the threshold that triggers climate catastrophe is known with certainty, and the benefits of avoiding catastrophe are high relative to the costs, treaties can easily coordinate countries’ behavior so as to avoid the threshold. Where the net benefits of avoiding catastrophe are lower,...

This paper investigates the welfare costs of unilateral versus internationally coordinated emission permit policies in a two-country overlapping generations model with producer carbon emissions. We show that, for a net foreign debtor country, the domestic welfare costs of a unilateral domestic...