Multi-Gas Strategy in Committing to the Kyoto Protocol

Though the Kyoto Protocol concerns six greenhouse gases, most appraisals in the past have focused exclusively on CO2. But it is now acknowledged that, at least for some countries, there is an important potential of abating non-CO2 greenhouse gases with a relatively low cost. It is then the topic of the paper to present a multi-gas assessment of the Kyoto Protocol and to compare the results with the single CO2 case. The assessment is done with GEMINI-E3, a world General Equilibrium Model. The first part of the paper describes the database and the methodology implemented in order to model non-CO2 greenhouse gases. The second part presents the results of the standard No Trade Kyoto scenario, with a single CO2 or a multi-gas strategy. Taking into account the potential of abatement of nonCO2 greenhouse gases greatly reduces the cost of committing to the Kyoto Protocol, but exhibits significant differences between countries according to the importance of the corresponding emissions in the initial situation.