In this paper, we study the impacts and effects of the number of countries and green technology on climate agreements. In a repeated climate game framework, we focus on the symmetric and self-enforcing weakly renegotiation-proof equilibrium. The set of every country’s feasible abatements is bounded and independent of the number of signatory countries. We derive the maximal number of signatory countries that can reach a fully cooperative (most efficient) climate agreement. We also analyze the maximal equilibrium abatement level when there are too many countries to sustain the fully cooperative agreement. The maximal equilibrium abatement level changes non-monotonically in the number of the countries; it first increases and then decreases in the number of countries involved. Our findings demonstrate a trade-off between the breadth and the depth for international climate agreements.

在本文中，我们研究了国家数量和绿色技术对气候协议的影响和影响。在重复的气候博弈框架中，我们集中于对称和自我实施的弱重新协商证明均衡。每个国家可行减排的范围是有界的，与签署国的数量无关。我们得出可以达成完全合作（最有效）的气候协议的签署国的最大数量。我们还分析了太多的国家无法维持全面合作协议时的最大平衡减排水平。最大均衡减排水平在国家数目中非单调变化；它首先增加，然后减少所涉国家的数量。