Evaluating indicators for the relative responsibility for climate change - alternatives to the Brazilian proposal and global warming potentials

摘要

In this paper, several indicators to describe the responsibility for climate change are discussed and evaluated. During the negotiations of the Kyoto Protocol, the delegation of Brazil proposed to use the impact of historical emissions on the current temperature. The Kyoto Protocol uses current emissions weighted by 100-year global warming potentials (GWPs) as the basis. As a powerful indicator historical responsibility proved the radiative forcing due to current concentrations integrated from today over a finite period into the future. Such indicator could be interpreted as a GWP for concentrations. The indicator is 'backward looking' (takes into account historical emissions), it is 'backward discounting' (early emissions weigh less depending on the decay in the atmosphere) and 'forward looking' (future effects of the emissions are considered) and it is comparable for all gases. The choice of the start date, from when historical emissions are accounted, is a political one.