National trajectories of carbon emissions: Analysis of proposals to foster the transition to low-carbon economies

In this paper we develop a framework for analyzing carbon dioxide (CO₂) emissions trajectories from the energy and industrial sectors of the world's nations under various policy options. A robust conclusion of our analysis is that early action by both developed and developing nations will be required to hold atmospheric CO₂ at or below doubled pre-industrial levels, and incentives for renewed investments in energy-sector technologies are a required component of early action. We therefore develop and examine an international emissions regime that: (a) in the short-term 'jump starts' the political and project-implementation process by providing incentives to exploit profitable or low-cost carbon reduction opportunities; (b) in the near- and medium-term addresses the inequities resulting from historic imbalances in greenhouse-gas emissions while promoting efficient pathways for carbon reduction; and (c) in the long-term recognizes the equal rights of individuals to exploit the services of the atmosphere and pursue a reasonable standard of living in a low-carbon economy. We present and analyze a proposal to promote near-term activity in carbon reduction and energy innovation through a revitalized program of international joint implementation (JI) projects for carbon emissions reduction or carbon sequestration projects. Under our proposal, JI partner nations both receive full credit for carbon reductions that can be 'banked' and applied at a later date toward national emissions quotas in the climate convention. A finite program lifetime provides further impetus for early action. This 'double counting' of credits results in only modest additional cumulative carbon emissions relative to a similar scenario without cooperative partnerships. This 'JI banking' plan promotes critically needed scientific and institutional experience and innovation, initiates cost-effective carbon reductions, and provides vital national flexibility in meeting eventual targets.