The Quality of an Emission Inventory Tinus Pulles CLRTAP International Workshop on Validation and Evaluation of Air Emission Inventories   Session 3 Validation and Review to meet Policy needs How to assess and manage uncertainties in emission inventories? Tinus Pulles TNO-MEP PO Box 342 7300 AH Apeldoorn The Netherlands m.p.j.pulles@mep.tno.nl

Issues in this presentation The concept of “data quality” Quality criteria How to achieve required quality Reviews In this presentation I will give an overview of how I see the different issues related to uncertainty assessment and management within the framework of international conventions and protocols. I will start riding my favourite horse: the concept of data quality and will extend this ride towards the quality criteria relevant within the policy use of emission inventories Before diving into the how, I will give my views on why we need to manage uncertainties in the first place. A short description will be given on the methods developed within the UNFCCC system in the IPCC National Greenhoude Gas Emissions Programme (IPCC-NIGGP) Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Perspectives on data Quality Quality high if … True ? Scientist … it produces predictions that are confirmed Scientific debate: search for weaknesses and errors; falsification Accepted ? Policy maker … everybody involved agrees Political debate: search for consensus and agreement; compromise Convinced ? Lawyer … it convinces a judge or jury Judicial debate: search for proof or doubt; persuasion Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Verification and Validation Policy oriented quality Guidelines applied ? validation Real world emissions Emission inventory Science oriented quality True ? verification Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Verification Validation methods: Error propagation Independent checks Measurements and models methods: quality control auditing country comparisons feed back Reliability objectives: Accuracy (no systematic error) Precision (no random error) objectives: Transparency Comparability Completeness Consistency Accuracy Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Policy oriented inventory: Quality check by UNFCCC Submitted Initial Check “Synthesis and Assessment” Expert Review In-depth finalizes the Review Inventory Accepted UNECE / CLRTAP Still under development Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Three stages of review Initial check Completeness: Type of review Objective of review Stage 1 Initial check Completeness: All data provided? (Counts, gaps) Stage 2 Comparisons and consistencies Compare with Earlier submissions (time series, jumps) Other parties (IEFs) Stage 3 Explanations and understanding Finalize and conclude Discuss and solve any problems between review process and national experts Ensure that the inventory is adequate and complies with the Guidelines Report to implementation committee Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Good practice guidelines Prepared by IPCC Accepted by UNFCCC Contents: Good practice guidance per sector Decision trees Default uncertainty values Additional information Methodology Uncertainty estimation Key source analysis QA/QC procedures Report in CRF & NIR Similar approach in EMEP/CORINAIR Guidebook for LRTAP a set of procedures intended to ensure that inventories are accurate in the sense that they are systematically neither over nor underestimates so far as can be judged, and that uncertainties are reduced so far as possible practicable. Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Decision tree Example Energy Guides user step by step through the procedure Supports methodology choice (Tier 1 or Tier 2) Proposes data to be looked for Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

How to get your inventory accepted Read the Good Practice Guidance and follow the recommendations Carefully plan the reporting cycle Deadlines Key sources ? Experts needed Data needed Document carefully all your assumptions all your data sources After first cycle use uncertainty analysis and key source analysis to improve your inventory year after year. Assessing and Managing Uncertainties in Emission Inventories 10/15/2002

Thank you Assessing and Managing Uncertainties in Emission Inventories 10/15/2002