1. IIASA Zbigniew Klimont International Institute for Applied Systems Analysis Uncertainties in the RAINS Estimates of National Emissions Based on: Suutari, R., Amann, M., Cofala, J., Klimont, Z., Posch, M. and Schöpp, W. (2001) From Economic Activity to Ecosystems Protection in Europe: An Uncertainty Analysis for two Scenarios of the RAINS Model. CIAM/CCE Report 1/2001. A study funded by the UK Department of Environment, Transport and the Regions (DEFRA).

2. IIASA Sources of uncertainties in emission calculation in the RAINS model Model structure Selected sectoral aggregation Determination of mean values ParametersExpected values for fuel quality, removal efficiencies Forcing functions Accuracy of statistical information on economic activities Projections of sectoral economic activities Future implementation of emission controls Initial stateUncontrolled emission factors State of emission controls in the base year

3. IIASA Methodology Emission calculations em= emission act = the activity level  = uncertainty factor for the activity level cef = controlled emission factor per unit of activity  = uncertainty factor for the emission factor ρ = coefficient of correlation Model: Expected emissions: Covariance:

4. IIASA Assumed uncertainties in input parameters Coefficients of variation SO 2 NO x NMVOCNH 3 Activity rates 1990 2010 0.06 - 0.20 0.12 - 0.30 0.025 - 0.25 0.05 - 0.40 0.05 - 0.50 0.10 - 1.00 Emission factors 0.05- 0.100.075- 0.150.05 - 0.350.15 - 0.40 Removal efficiencies 0.005- 0.050.015- 0.100.005 - 0.250.05 - 0.15

5. IIASA Top 10 SO 2 source sectors UK, 1990 and 2010

6. IIASA Top 10 NO x source sectors UK, 1990

7. IIASA Sensitivity Analysis for UK Emission Estimates

8. IIASA Uncertainties in national emissions in 1990 and 2010 [95% confidence interval] SO 2 NO x NMVOCNH 3 France ± 6/16 %± 11/12 %± 10/13 %± 11/14 % UK ± 11/15 %± 10/11 %± 9/14 %± 12/17 % Germany (NL) ± 16/15 %± 15/12 %± 18/17 %± 16/15 % Bulgaria ± 21/22 %± 13/17 %± 11/13 %± 18/20 % Slovakia ± 12/13 %± 12/16 %± 14/20 %± 19/19 % Slovenia ± 21/30 %± 21/19 %± 13/18 %± 21/22 %

9. IIASA Conclusions Methodology is now available, but conclusions are still incomplete and preliminary: The most uncertain elements in uncertainty analyses are the uncertainties Correlations, distributions difficult to quantify Error compensation potential determines uncertainties of estimates Implication for design of emission inventories