Verification Times Underlying the Kyoto Protocol: Consideration of Risk

this paper proposes a probabilistic (risk-based) approach to address verification of changes in global net carbon emissions - here, the change in atmospheric CO2 and CO2 emissions from fossil fuel combustion, cement production and gas flaring, under the Kyoto Protocol. A methodology is developed that permits assessing these net emission changes, which are characterized by uncertainty distributions, in terms of their verification times. The verification time is the time until a net emission signal begins to outstrip its underlying uncertainty. For a number of reasons, namely (1) data availability, (2) consistency in accounting net carbon fluxes, and (3) spatio-temporal conditions, which correspond to the current level of sophistication that is realized in the approach, it is applied to the global scale. However, the temporal verification conditions of the approach correspond to those on sub-global scales, in accordance with the Protocol. Two conclusions emerge from this study: (1) characterizing changes in global net carbon emissions by equal-sided (symmetric) uncertainties, as practised by the Intergovernmental Panel on Climate Change, leaves valuable information unutilized; and (2) the comparison of probabilistically and deterministically determined verification times show that they differ - the probabilistic verification time tends to be greater (more conservative) compared with the deterministic verification time.