『Abstract
We investigated the Austrian national greenhouse gas emission
inventory to review the reliability and usability of such inventories.
The overall uncertainty of the inventory (95% confidence interval)
is just over 10% of total emissions, with nitrous oxide (N2O) from soils clearly providing the largest impact.
Trend uncertainty - the difference between 2 years - is only about
five percentage points, as important sources like soil N2O are not expected to show different behavior
between the years and thus exhibit a high covariance. The result
is very typical for industrialized countries - subjective decisions
by individuals during uncertainty assessment are responsible for
most of the discrepancies among countries. Thus, uncertainty assessment
cannot help to evaluate whether emission targets have been met.
Instead, a more rigid emission accounting system that allows little
individual flexibility is proposed to provide harmonized evaluation
uninfluenced by the respective targets. Such an accounting system
may increase uncertainty in terms of greenhouse gas fluxes to
the atmosphere. More importantly, however, it will decrease uncertainty
in intercountry comparisons and thus allow for fair burden sharing.
Setting of post-Kyoto emission targets will require the independent
evaluation of achievements. This can partly be achieved by the
validation of emission inventories and thorough uncertainty assessment.
Keywords: model uncertainty; Monte Carlo simulation; greenhouse
gases; inventory quality considerations; Kyoto Protocol』
1. Introduction
2. Methodology: How to assess the uncertainty of national emission
inventories
3. Results
4. Discussion
4.1. Excluding sources with high uncertainty
4.2. Covariance and the definition of adequate system boundaries
4.3. Significance of subjective interpretation of uncertainty
4.4. Rigid accounting as a method of assessing emissions
5. Conclusions
References