Regional and sub-global climate blocs. A game-theoretic perspective on bottom-up climate regimes

controlling GHG emissions without the involvement of countries such as China, India, the United States, Aust rali a, and possibly other developing countries. This highlights an unambiguous weakness of the Kyoto Protocol, where the aforementioned countries either have no binding emission targets or have decided not to comply with their targets . Therefore, when discussing possible post-Kyoto scenarios, it is crucial to priori tise part icipation incentives for all countries, especially those without explicit or with insufficient abatement targets. This paper offers a bottom-up game-theoretic perspective on participation incentives. Rather than focusing on issue linkage, t ransfers or burden sharing as tools to enhance the incentives to par t icipate in a climate agreement, thi s paper aims at exploring whether a di fferent policy approach could lead more count ries to adopt ef fective climate cont rol policies. This policy approach is explicitly bottom-up, namely i t gives each country the freedom to sign agreements and deals, bilateral ly or multila terally, with other countries, without being constrained by any globa l protocol or convention. This study provides a game-theoretic assessment of this policy approach and then evaluates empirically the possible endogenous emergence of single or multi ple climate coalitions. Welfare and technological consequences of different mul tiple bloc climate regimes will be assessed and their overall environmental effectiveness will be discussed.