CATRINE · Carbon Atmospheric Tracer Research to Improve Numerics and Evaluation

The CATRINE project will focus on the atmospheric tracer transport research areas identified by the EU's CO2 Task Force, the CO2 Human Emissions (CHE) project, and the Copernicus CO2 service (CoCO2) projects. The accuracy and mass conservation of the tracer transport model is of utmost importance in the design of the CO2MVS. Any unaccounted systematic errors in the tracer transport model can lead to inaccuracies in the estimation of CO2 and other tracer emissions. Therefore, CATRINE aims to improve the methods used to represent resolved tracer transport by the winds, with a particular focus on mass conservation, and to identify other systematic errors associated with unresolved processes represented by parametrizations. The project will define protocols for evaluating tracer transport models at both global and local scales. Test beds based on field campaign case studies will be developed, along with suitable metrics for tracer transport evaluation, utilising a range of tracers and observations at both global and local scales. These metrics will be employed in the operational CO2MVS to evaluate the implementation of new transport model developments, characterise transport accuracy and representativity in data assimilation, and provide a quality control stamp of tracer transport accuracy. Lastly, CATRINE will provide clear recommendations to the CO2MVS and the Carbon Cycle Community which works with atmospheric inversion models for the evaluation and quality assessment of tracer transport models.