The stabilization of atmospheric greenhouse gas concentrations and the avoidance of serious or irreversible impacts on the earth’s climate system are a matter of critical concern in both scientific and policy arenas. Using the most current science available, this study will evaluate the implications of different atmospheric concentration target levels and explain the uncertainties inherent in the analyses to assist policy makers as they make decisions about stabilization target levels for atmospheric greenhouse gas concentrations.

This study will:

• Evaluate a range of greenhouse gas stabilization targets and describe the types and scales of impacts likely associated with different ranges, including discussion of the associated uncertainties, timescale of impacts, and potential serious or irreversible impacts.*

This study will focus on evaluating the implications of a range of GHG stabilization targets, but it will not involve the committee’s assessment of what stabilization targets are technically feasible nor their normative judgment on what targets are most appropriate.

* This study will consider cumulative emissions of the ‘basket’ of gases considered in the Kyoto protocol (CO2, CH4, N2O, HFCs, PFCs, SF6). Any particular overall stabilization target could include varying combinations of emissions targets for the different gases.