1. Presentation title
Second workshop on the revision of the UNFCCC Annex I reporting guidelines
Time-series consistency and recalculations
Bonn, Germany, 3–4 November 2010
Astrid Olsson, Programme Officer
UNFCCC secretariat, programme

2. Time-series consistency and recalculations
Presentation title
Time-series consistency and recalculations
Background
Time-series consistency
IPCC good practice guidance introduced the concept of time-series consistency
Annex I Parties are required to submit full CRF tables for all years of the time series; from the base year to the latest inventory year, in accordance with the current UNFCCC reporting guidelines
All years of the time series should be estimated using the same methodologies
Underlying AD and EFs should be obtained and used in a consistent manner
Recalculations (current UNFCCC reporting guidelines)
Should ensure consistency of time series
Shall be carried out only to improve accuracy and/or completeness
Where methodology or manner in which underlying AD and EFs are gathered has changed Annex I Parties should recalculate base year and subsequent years

3. Time-series consistency and recalculations
Presentation title
Time-series consistency and recalculations
Issues raised in Parties’ submissions relating to time-series consistency and recalculations
Small differences, e.g. due to rounding of estimates, should not be considered as recalculations
Parties should report base year, 1990, 1995, 2000, 2005 and all subsequent years up to the latest inventory year
If reporting requirements and CRF tables are changed a lot this will lead to an extensive need for recalculations. For new categories data sources might not be available. Ways to resolve these problems:
Chapter 5 of the 2006 IPCC Guidelines “Time series consistency” could be expanded to include methodologies for ensuring time-series consistency in cases where the 2006 IPCC Guidelines and the relevant CRF tables differ from the current version of the UNFCCC reporting guidelines.
Changes to CRF tables should only be done when necessary (e.g. inclusion of new categories or obvious shortcomings of the current CRF tables)

4. Time-series consistency and recalculations
Presentation title
Time-series consistency and recalculations
Discussion points
If Parties do not report CRF tables for the complete time series, but for selected years; e.g. base year, 1990, 1995, 2000, 2005 and all subsequent years up to the latest inventory year; how can time-series consistency be ensured?
If Parties only report selected years, should just these years be recalculated or should the complete time series be recalculated and only the selected years be reported?
Small differences e.g. due to rounding of estimates should not be reported as recalculations. How can it be ensured that the changes are not “real” recalculations?
What is the definition of “small”?
Can current techniques contained in the 2006 IPCC GL/IPCC GPG be applicable for back-casting new methods to earlier years of the time series when there is either a paucity of or no data available?
What other techniques could be considered for recalculations in addition to those provided in the 2006 IPCC Guidelines?