Fair international protocols for the abatement of GHG emissions

We study the design of fair international protocols for the abatement of GHG emissions. We formulate normative principles, pertaining to countries' population, emission history, and (business as usual) future emissions, as axioms for allocation rules. We show that combinations of these axioms characterize the so-called equal per capita allocation rules, with or without historical accountability. The allocations provided by these rules are in stark contrast with the allocation suggested by the Kyoto protocol, which is close to the allocation in proportion to the current and business-as-usual emissions, suggested by the equal per emission (grandfathering) rule. As we illustrate, equal per capita allocations admit more emissions to developing countries with large populations. And, with historical accountability, developed countries with large historical emissions are clearly penalized.