Uncertainties in the Finnish 2002 Greenhouse Gas Emission Inventory

This report is a part of Finland's greenhouse gas inventory work to the United Nations Framework Convention on Climate Change. A detailed uncertainty estimate, based on Monte Carlo simulation, was performed first time for the 2001 inventory. This report presents the changes in uncertainty estimates related to the previous inventory, as well as the uncertainties in the 2002 inventory. In this study, some input parameter uncertainty estimates were revised, and the uncertainty calculation method was changed for the Energy sector. The uncertainty calculation model was also developed further during the project. In 2002, the total uncertainty in the inventory was -5 to +6%. In absolute terms, the emissions (covered by this uncertainty estimate) in 2002 were 76 to 85 Tg (CO2 equivalents) with 80 Tg as the most likely value. The trend uncertainty was 5% points. This means that the increase in emissions from 1990 to 2002 was between 3 and 10 Tg (CO2 equivalents) with 6 Tg as the most likely value. When compared with the previous uncertainty estimate, the aggregated relative uncertainties have not been changed. The most important sources affecting the uncertainty in 2002 were CO2 emissions from peat lands and N2O emissions from agricultural soils. The uncertainty estimate does not cover land use, land-use change and forestry.