Action 2.6: Enhance in-depth review mechanisms for reported black carbon emissions

The AC Framework does not provide a formal review mechanism for submitted black carbon emission inventories. Furthermore, until rather recently, submitted emissions of black carbon had not been thoroughly assessed during the independent expert reviews under EU NECD review or the stage 3 reviews under the Air Convention - due to resource prioritisation and black carbon status as pollutant reported on a voluntary basis. The national black carbon emissions reported by the EU Member States were centrally examined in the in-depth NECD review during 2021. Up to and including 2018, the stage 3 reviews under the Air Convention concentrated solely on the emissions of mandatory pollutants.

However, plans to devote more attention to black carbon within the scope of the in-depth reviews under the Air Convention are being gradually developed and implemented. Since 2017, initial (stage 1) and extended (stage 2) controls performed by CEIP/EMEP have been expanded to cover reported black carbon emissions. In 2018, the Air Convention Executive Body Decision (2018/01) on Updated methods and procedures for the technical reviews of air pollutant emission inventories reported under the Convention reaffirmed that CEIP stage 3 reviews would continue to focus on the mandatory pollutants; however, the Decision also stated that other non-mandatory pollutants including black carbon “shall also be reviewed as resources allow”. Since this decision, stage 3 reviews of 11 Parties in 2019 and 2020 have indeed examined national black carbon emissions reported by the respective countries, and reviewers provided the Parties with explicit recommendations on methodological improvements in key categories (i.e. significant source sectors). In 2022 and 2023, ad hoc reviews that focus on a certain topic have been performed. The two topics did not set the focus on black carbon emissions. Also, for the coming years ad hoc reviews focusing on certain topics are planned. If black carbon is a relevant pollutant for the topic under review it is planned to include it in the review (as resources allow).

The above developments with respect to inventory reviews under the Air Convention and EU NECD indicate notable progress and should be monitored closely over the next years. Given that black carbon is a non-mandatory pollutant, the review findings and recommendations under the Air Convention cannot be enforced; however, they would increase the transparency of the reporting systems and may stimulate improvements of the inventories at the national level. Under EU NECD, the inventory review results in recommendations and sometimes technical corrections enforced in the EU Member States reporting BC.

The degree to which reviews will help to improve reported black carbon emissions will depend on whether this initial review effort can be sustained and enhanced. For the EU NECD inventory review, a light review of black carbon emissions including a follow-up review to assess the implementation of the recommendation for black carbon inventories is planned for future years (EU Tender, ENV/2023/OP/0010).

Improvements brought by sustained and enhanced reviews of black carbon under the Air Convention and/or EU NECD, would also translate into improved data for monitoring black carbon emissions under the Arctic Council Framework, given that all Arctic Council Member countries are Parties to the Air Convention and/or Member States of the EU. It can therefore be considered that ECBCM follows developments on this front and investigates how the review results (e.g. the publicly available review reports here and here) may be used to assess progress of the implementation of AC Framework.