Periodic Reporting for period 1 - AVENGERS (ATTRIBUTING AND VERIFYING EUROPEAN AND NATIONAL GREENHOUSE GAS AND AEROSOL EMISSIONS AND RECONCILIATION WITH STATISTICAL BOTTOM UP ESTIMATES)
Reporting period: 2023-01-01 to 2024-06-30
The reporting of national greenhouse gas (GHG) emission inventories is a crucial element in the 2015 Paris Agreement under the United Nations Framework Convention on Climate Change (UNFCCC). However, the reported emissions carry substantial uncertainties and lack independent verification. The AVENGERS (Attributing and Verifying European and National Greenhouse gas and aerosol Emissions and Reconciliation with Statistical bottom-up estimates) project brings together European experts to establish top-down techniques in support of the verification of national greenhouse gas (GHG) inventories. AVENGERS will make use of atmospheric inverse modelling and data assimilation, remote sensing, environmental monitoring and observation, terrestrial ecosystem modelling, policy and stakeholder interaction together with national inventory compilers in order to improve the methods and approaches currently used in GHG emission inventory reporting. AVENGERS will advance the top-down approach for quantifying GHG and aerosol emissions by adding additional tracers (e.g. radiocarbon, co-emitted species, black carbon), as well as reconcile and integrate approaches into a joint bottom-up and top-down framework. Based on the reconciliation, AVENGERS will prepare good-practice guidelines for use of atmospheric inverse models as well as develop a Flexible Inversion Tool for Inventory Compilers (FIT-IC). Knowledge and outcomes are provided for use to policy and societal stakeholders and replicable outside of the chosen target areas of the project (Europe with a focus on Germany, Italy, Sweden, Switzerland, and The Netherlands). The uniqueness of the consortium lies in the combination of the required scientific expertise with full partner presence of official reporting agencies from exemplary EU countries facilitating the transfer of knowledge to key stakeholders (the national reporting agencies and international organisations such as UNFCCC, WMO) in the field.
The work performed through AVENGERS will lead to a better understanding of how the different communities, including atmospheric scientists, process-based land surface modelers and inventory compilers, can work more effectively together. The main achievements of AVENGERS will include:
- Good practice guidelines on how top-down emission estimation systems can support greenhouse gas (GHG) inventories and the Global Stocktake;
- A Flexible Inversion Tool for Inventory Compiler (FIT-IC) for demonstrating the strengths and weaknesses in estimating GHG emissions, made available to national inventory compilers including training events;
- Observation-based estimates of GHG (CO2, CH4, N2O) and aerosol emissions and their uncertainties for European countries (with a specific focus on Germany, The Netherlands, Sweden and Switzerland such that they can be used as input in the respective GHG inventories);
- Improved estimates of uncertain emission factors used in the inventories, based on process modelling in ORCHIDEE and LPJ-GUESS of Sweden and Italy for the Agriculture, Forestry and Other Land Use (AFOLU) sector; and
- The evaluation of future observing systems (both satellite and in-situ) in terms of their potential to further reduce uncertainties in the estimated GHG and aerosol emissions and corresponding guidelines on the design of the networks.
- Good practice guidelines on how top-down emission estimation systems can support greenhouse gas (GHG) inventories and the Global Stocktake;
- A Flexible Inversion Tool for Inventory Compiler (FIT-IC) for demonstrating the strengths and weaknesses in estimating GHG emissions, made available to national inventory compilers including training events;
- Observation-based estimates of GHG (CO2, CH4, N2O) and aerosol emissions and their uncertainties for European countries (with a specific focus on Germany, The Netherlands, Sweden and Switzerland such that they can be used as input in the respective GHG inventories);
- Improved estimates of uncertain emission factors used in the inventories, based on process modelling in ORCHIDEE and LPJ-GUESS of Sweden and Italy for the Agriculture, Forestry and Other Land Use (AFOLU) sector; and
- The evaluation of future observing systems (both satellite and in-situ) in terms of their potential to further reduce uncertainties in the estimated GHG and aerosol emissions and corresponding guidelines on the design of the networks.
AVENGERS plans to go beyond the current state-of-the-art concerning methodological/technological developments, system integration and networks. Progress Beyond the State-Of-The-Art (PBSOTA) to be achieved by AVENGERS includes:
- Advances in data assimilation/inverse modelling: the project will use new and improved tracers for the estimation of anthropogenic emissions to reduce the problem of under constrained inversions (such as radiocarbon for fossil CO2 emissions, CH4 isotopes for improved CH4 source attribution, combined surface and satellite data inversions).
- Improved prior emissions fields for inverse modelling systems: AVENGERS will update the anthropogenic GHG and aerosol emission fields to recent years as gridded maps, ensuring consistency of the GHG emissions with the national gridded inventories, improve temporal emission profiles per country and GHG species as well as on uncertainty estimates, and improve the gridded inventories with respect to vertical distribution of emissions, point source locations and GHG species.
- Improved inverse estimates of aerosol emissions: estimating aerosol emissions at high resolution in the European domain, making intercomparisons of different estimation techniques and assessing the impact of future satellite missions.
- Process attribution and emissions factor estimation: making use of the the most recent versions of two second generation dynamic vegetation models for quantifying emissions from forest management.
- The assessment of the potential of observational network extensions (future satellite missions such as CO2M as well as in-situ): through observation system simulations experiments and Quantitative Network Design studies.
- Reconsiliation of GHG emissions and comparisons of GHG and aerosol radiative forcing: atmospheric scientists and inventory compilers will work in close collaboration in the reconciliation of the top-down and bottom-up estimates with robust uncertainty assessment.
- Advances in data assimilation/inverse modelling: the project will use new and improved tracers for the estimation of anthropogenic emissions to reduce the problem of under constrained inversions (such as radiocarbon for fossil CO2 emissions, CH4 isotopes for improved CH4 source attribution, combined surface and satellite data inversions).
- Improved prior emissions fields for inverse modelling systems: AVENGERS will update the anthropogenic GHG and aerosol emission fields to recent years as gridded maps, ensuring consistency of the GHG emissions with the national gridded inventories, improve temporal emission profiles per country and GHG species as well as on uncertainty estimates, and improve the gridded inventories with respect to vertical distribution of emissions, point source locations and GHG species.
- Improved inverse estimates of aerosol emissions: estimating aerosol emissions at high resolution in the European domain, making intercomparisons of different estimation techniques and assessing the impact of future satellite missions.
- Process attribution and emissions factor estimation: making use of the the most recent versions of two second generation dynamic vegetation models for quantifying emissions from forest management.
- The assessment of the potential of observational network extensions (future satellite missions such as CO2M as well as in-situ): through observation system simulations experiments and Quantitative Network Design studies.
- Reconsiliation of GHG emissions and comparisons of GHG and aerosol radiative forcing: atmospheric scientists and inventory compilers will work in close collaboration in the reconciliation of the top-down and bottom-up estimates with robust uncertainty assessment.