English Abstract This report highlights the consequences of two policy
scenarios of concern to the Climate Convention. In the first scenario CO2
would be stabilized in the atmosphere at 350 ppm by the year 2150 (367 ppm
by 2100) ; in the second scenario it would be stabilized at 450 ppm in
2100. Among the main findings of this report are: - To achieve these
stabilization targets, global emissions are not allowed to substantially
increase at any time in the future, and eventually they must be
significantly reduced. - Because of the current upward trend in global
emissions, there is a large policy gap between the allowable emissions for
stabilizing greenhouse gases, and the emissions that will occur if no action
is taken. - Stabilization scenarios lead to much lower impacts on crop
productivity, natural vegetation, and sea level rise as compared to the
baseline case. - Although the stabilization scenarios show lower impacts
than a baseline, they are not "risk-free". Some impacts do occur, and to
further reduce these impacts would require more stringent stabilization
targets.
