1. Improvements of the Netherlands’ Greenhouse Gas Inventory & resulting (lower) uncertainties ? Uncertainty Workshop, Helsinki 5-6 September 2005 H.H.J. Vreuls, SenterNovem

2. Outline Dutch GHG emissions Recalculations of GHG emissions Uncertainty analysis –TIER 1 uncertainty assessment –TIER 2 uncertainty assessment Conclusions

3. GHG Emissions Netherlands 1990: 211,7 Tg2003: 214,8 Tg

8. Reasons for recalculation 2005 IPCC reporting requirements –Transparency –Completeness –Consistency in time series –Compliance with the IPCC guidelines –Accuracy Results from improvement programme Input from uncertainty analysis

9. Recalculations and emission data in the base year 1990 CO 2 : - 2,6 Tg (excluding LUCF) + 1,7 Tg (including LUCF) CH 4 : - 1,5 Tg CO 2 -eq N 2 0: + 3,8 Tg CO 2 -eq F-gases– 0,04 Tg CO 2 -eq (1995)

10. Differences between NIR 2004 and NIR 2005 for the emission trends 1990-2002 1) Excluding LUCF

11. TIER 1 Methodology uncertainties; assumptions All individual emissions sources are independent from each other The emission probability shows normal (Gaussian) distributions Uncertainties are smaller than + 60%

12. Top 12 sources in total annual uncertainty IPCC code IPCC Source categoryTg CO 2 -eq 1990 Tg CO 2 -eq 2003 Activity data uncert. Emission factor unc. Total Uncertainty 1A1CO 2 from stationary combustion: energy industry12.06.83%2%4% 1A2 CO 2 emissions from stationary combustion : Manufacturing Industries and Construction32.827.13%1%3% 1A3CO 2 from stationary combustion: other sectors38.040.610%1%10% 1A3bCO 2 mobile from combustion: road vehicles25.533.42% 3% 2BN 2 O from nitric acid production6.35.110%50%51% 4A1 CH 4 from enteric fermentation in domestic livestock: cattle6.65.45%20%21% 4BCH 4 from manure management: cattle1.61.410%100% 4BCH 4 emissions from manure management : swine1.10.910%100% 4DDirect N 2 O from agricultural soils4.64.810%60%61% 4DIndirect N 2 O from nitrogen used in agriculture5.03.350%200%206% 5CO 2 from Land Use Change and Forestry2.92.8100% 141% 6ACH 4 from solid waste disposal sites51.065.815%30%34% Sum of emissions (percentage of total greenhouse gas emissions) 187.4 (87%) 197.3 (91%)

13. Adding uncertainty information IPCC Source categoryTg CO 2 -eq. Activity data uncert. Emission factor uncert. Total uncertainty 1ACH 4 from stationary combustion 0.53%50% 1A3dCO 2 from mobile combustion: navigation 0.650%2%50% 1B1CO 2 from coke production 0.550%2%50% 1B2CH 4 from fugitive emissions oil/gas: gas distribution 0.52%50% 2FSF 6 from SF 6 use0.350%25%56% 4BN 2 O from manure management0.610%100% 6BN 2 O from wastewater handling0.420%50%54% Sum of emissions ( percentage of total greenhouse gas emissions) 3.4 (2%)

14. Uncertainty in annual total national greenhouse gas emissions Greenhouse gas NIR 2004 calculated (reported) uncertainty NIR 2005 calculated (reported) uncertainty Carbon dioxide ± 2% (± 3%) ± 4% (± 5%) Methane± 17% (± 25%)± 18% (± 25%) Nitrous oxide± 34% (± 50%)± 53% (± 50%) F-gases± 21% (± 50%)± 11% (± 50%) Total CO 2 -eq. ± 4% (± 5%)± 6% (± 7%)

16. No decrease of uncertainties after recalculations Application of new methods Uncertainties of newly identified key sources –CO 2 emissions from LUCF –Indirect N 2 O emissions from agricultural soils For F-gases higher quality activity data and more accurate emission data

17. Tier 2 uncertainty analysis Correlations between emission sources Specific probability density functions Conducted in the Netherlands using 1990 and 1999 data –Using Monte Carlo method –Also qualitative uncertainty

18. Qualitative uncertainty: Typology of uncertainties Uncertainty due to variability –Natural randomness –Value diversity –Behavioral variability –Social randomness –Technological surprise Uncertainty due to limited knowledge –Measurable uncertainty –Structural uncertainty

19. Uncertainty due to limited knowledge Measurable uncertainty –Inexactness –Lack of observation/measurements –Practical immeasurable –Conflicting information Structural uncertainty –Reducible ignorance –Indeterminacy –Irreducible ignorance

20. Tier-1 and Tier-2 uncertainty assessment 1999 Greenhouse gasTier 1 uncertainty Tier 2 uncertainty Carbon dioxide 2.7% 1.6% Methane16%15% Nitrous oxide36%29% F-gases20% Total CO 2 -eq. 4.5% 3.6%

21. Elements in the update TIER 2; about to start October 2005 Updated and new information on expert judgment Key areas of interest for research Sensibility analysis using min/max values from EU member states Research on PDF and sources of uncertainty for selected areas TIER 2 uncertainty analysis 1990-2003

22. Conclusions Uncertainty assessments (TIER1 and 2) are used as a tool to prioritise improvements for GHG emission inventory More complex uncertainty assessments (TIER2) did not result in surprising, other insights Changes in methods resulting in recalculation did not result in ‘ better’ uncertainty values

23. Conclusions (continue) Possible impact of methodological changes seems not to be included in uncertainty assessments Update TIER 2 based on recalculated data and to justify no follow up of new TIER 2 for the next five years