Include all sources,consistent with 1996
Revised Guidelines*

Inventory
Completenesssources

Methodological Use good practicemethods for important
Approach

Good PracticeElement

Type ofChallenge

Identify options for national
determination of importantsourcesDevelop framework for“good practice method”
approach(should reflect varied
national circumstances)

Define terms

2. Examples ofprioritisation techniques

3. National input oncurrent practice
1. Proposals offrameworks from countries

2. Possible secretariat
review of use of terms

1. Current IPCC
guidance on use of terms(Before meeting)General Requirements Inputs

Annex 3: Issues for Sectoral Workshops to Consider

Specify meaning of
good practice methods
source by source

Ensure consistency inuse of terms at sectorallevel

SectoralRequirements

Guidance that
customises framework tosources

Sectoral guidance on useof terms(to be included inreport)

Outputs

Inventory
Quality

Define key elements of goodpractice (measurements,scaling etc.)

Define key elements of goodpractice

Establish general
requirements of a QA/QC
systemEstablish elements oftransparency:-tiers-rationale for approach-reproducibility-documentation andreferences-explanation of changes
in key factors andassumptions

Use good practice inobtaining emission factors
or model parameters

Use good practice inobtaining activity factor
data

System for QA/QC

Transparency

2. National input oncurrent practice

2. National inputs oncurrent practice
1. Background document
summarising possible
elements (with case studies
wherepossible)

National inputs-current data
sources-key issues (such asbias, informal sector,
confidentiality
1. Background document
summarising relevant
QA/QC systems (e.g.
ISO9000, EIIP)

2.

1. Background paper on
key issues with respect toactivity data

Evaluate applicability
at source level (e.g.
technical aspects,resource requirements)

Evaluate applicabilityof general procedures
to individual sources(e.g. technical aspects,resource requirements)

Evaluate key issues atsource level

Review IPCC default
emission factors

2.

National inputs-key issues-current factors-research program

Evaluate key issues atsource level

1. Background paper on
key issues with respect toemission factors

Guidance ontransparency at sourcelevel

Input to QA/QC
workshop

Guidance on goodpractice in QA/QC atsector level

Develop sectoral
guidance, on
use/development ofemission factors
Includerecommendations foremissions factors(regional/national/Technology-based)
and/or model parameters
Develop sectoral
guidance

General guidance

Encourage continued
advance in “state of theart”

Identificationof Priority
Areas(weaknesses)

See above

2. National input oncurrent submissions
1. Compilation ofexisting materials (e.g.
Cuba, Bilthoven, nationaletc.)
2. National input onpriority areas

3. Preliminary default
factors included in source
reports
1. Compilation of current
requirements and guidance

2. National input oncurrent practice

1. Background document
summarising key issues
and data available

1.

Discuss priority areas

Discuss technicalaspects ofrequirements andguidance

Identify types ofexperts and scope ofreview
Discuss Group A
questions at
sector/source level

Guidance on fulfillingformal requirements
Recommendation offuture work program

Recommendation fortechnical revisions

Feedback to Group A

Guidance on sectoral
uncertainty analysis

Guidance on domestic
review*All of these issues apply to all categories. Land-use change and Forestry is not explicitly addressed because it is the subject of another IPCC work programme.

Sensitivity analysis

Standard tables andsupplemental information

Meet formal requirements

Develop framework forassessment of uncertainty(Group A)

Uncertainty Uncertainty Assessment

ReportingIssuesDescribe as part of overallsystem

Domestic review process(peer and public review)

Annex 4: Description of the Uncertainty Framework
Introduction
The UNFCCC is starting probably the largest environmental monitoring programme in the world.
The uncertainty work must focus on key processes, it must consider internal and external
uncertainties in inventories and how to treat them. There is a need to properly quantify uncertainties
in order to prioritise environmental research to help provide more accurate emission estimates. The
measures of uncertainty should over time chart the improvements made in the inventory
methodology and data. Examples of this interactive activity are given in the country studies.
Uncertainty in greenhouse gas inventories is inevitable and stems from limitations to our knowledge
about the processes which generate emissions and uptakes. Key limitations include:•our knowledge about the variety of processes which generate emissions;•the number of measurements available to develop models or algorithms for thecalculation of emissions and uptakes,•

the resources we are able to assign to collecting statistical data necessary for the
preparation of inventories, and•the inherent variability of the systems being considered.

Uncertainty can be reduced through additional research and/or expanded measurement programs, but
it cannot be completely eliminated. Therefore, we must decide how best to work with the data andresources available to us, taking full account of the need to accommodate the circumstances of allParties.
The national case studies presented in Paris and the assessments by the UNFCCC secretariat suggestthat the absolute uncertainty in national inventories in a given year may be 20% or more at the 95%
confidence limit. They also suggest that the uncertainty in the trend, though less than this, is still
likely to be comparable to the level of commitments.
Parties can manage uncertainty and minimise bias by following good practice guidance in compiling,assessing and reporting inventories using the IPCC yardsticks of consistency, comparability andtransparency.
As greenhouse gas inventories continue to improve, so will the ability to model atmosphericconcentrations and their trends.
When these calculated emissions agree with observed
concentrations, we will be able to effectively assess the impact of future and different emission
controls on atmospheric concentrations of greenhouse gases.

Definitions and Constraints
An essential aspect of the development of an uncertainty framework for national greenhouse gas
inventories is the development of an agreed set of definitions of the technical terms used. Definitions
can be drawn from the statistical literature, but in most cases these definitions are broader than themeanings used in the context of inventory uncertainties, and in some cases multiple meanings exist in
the statistical literature. Therefore one task of the uncertainty sub-group is to develop a glossary of
key terms incorporating both the relevant accepted statistical definition and the specific meaning of35