Following completion of the trial period for inventory reporting and review, annual review of individual
inventories of each Annex I Party became mandatory in 2003 (decision 19/CP.8). The UNFCCC inventory review
guidelines, adopted in 1999 (decision 6/CP.5) and revised in
2002 (decision 19/CP.8), ensure that the reviews are conducted consistently in a technically sound manner.
Annual review ensures that adequate consideration is given to recalculations and emission trends over
The review of GHG inventories comprises three stages. Each stage complements the previous one, and ensures that
the process as a whole provides a thorough and technical assessment of the inventory and of conformity with the
UNFCCC and IPCC guidelines. Each stage of the review is finalized with a review report which is published on
the secretariat web site (see navigation bar to left).
Initial check: immediate quality assurance check to verify that the inventory submission
is complete and in the correct format. The result is a status report whose main purpose is to provide a
brief check of completeness of the inventory submission, mainly based on the CRF.
Synthesis and assessment: Part I compiles and compares basic inventory information, such
as emission trends, activity data and implied emission factors, across Parties and over time. Part II
provides a ‘preliminary assessment’ of the inventory of individual Parties. The identification
of potential problems in this assessment is an important input to the individual review stage.
Individual review: international teams of sectoral inventory experts examine the data,
methodologies and procedures used in preparing the national inventory. Reviews are conducted as a
centralized review, where 5–8 inventories are reviewed by an expert review team (ERT) convened at the
secretariat; a desk review, where 3–5 inventories are reviewed by experts based in their home
countries; or an in-country review, where a single inventory is reviewed by an ERT in the Party under
review. This is the most important and detailed review stage.
Protection of confidential inventory information
At COP 9 by decision 12/CP.9 Parties adopted a code of practice for the treatment of confidential information
in the technical review of greenhouse gas inventories from Parties included in Annex I to the Convention. In
accordance with this decision, the secretariat has developed procedures to implement the code of practice
during the inventory review in 2004 and beyond. These procedures cover submission, processing and handling by
the secretariat of any information designated as confidential by an Annex I Party, and the granting of access
by expert reviewers to this information.
Expert review teams
The annual inventory review process requires the participation of over 120 skilled experts per year. Members
of expert review teams are selected by the secretariat from experts nominated by Parties. The secretariat
selects experts to ensure coverage of all inventory sectors, and to achieve an overall balance in the
participation of experts from Annex and non-Annex I Parties, as well as geographical balance among them. Two
lead reviewers, one each from an Annex I and a non-Annex I Party, guide the work of the teams.
Participation of experts nominated by Parties helps to ensure that the review results are objective, credible
and recognized by Parties. In addition, it helps build inventory capacity across all Parties. Reviewed
Parties receive technical feedback from other experts that enables them to further improve their inventories.
Likewise, experts who participate in reviews gain knowledge of inventory practices of other countries, which
they can take home and apply to their own inventories.
As of 2004, all members of expert review teams participating in the technical review of greenhouse gas
inventories must sign an agreement for expert review services. The agreement specifies the responsibilities,
expected time commitment, and appropriate conduct for expert review team members, in particular with respect
to the protection of confidential inventory information, as determined by the COP. Any new review team
members must also successfully complete training on how to perform a review.
Lead reviewers meetings
Under the UNFCCC review guidelines (FCCC/CP/2002/8), expert teams for review of GHG inventories are to be led
by two experts with substantial inventory review experience. For each team, one lead reviewer is to be from a
non-Annex I Party, and one from an Annex I Party. These lead reviewers have a special role in guiding the
review teams to ensure the quality, consistency and objectivity of the reviews. Recognizing the special role
of lead reviewers, the COP requested the secretariat to organize meetings of lead reviewers to promote a
common approach by expert review teams to methodological and procedural issues encountered in the inventory
reviews, and to make recommendations to the secretariat on ways to further improve the effectiveness and
efficiency of the inventory reviews. The secretariat has conducted eleven meetings of inventory lead
reviewers. The conclusions of these meetings are presented through the following links: