Marine Ecosystem forecasts: skill performance of the CMEMS Mediterranean Sea model system

Abstract. The quality of the upgraded version of the CMEMS biogeochemical operational system of the Mediterranean Sea (MedBFM) is assessed in terms of consistency and forecast skill, following a mixed validation protocol that exploits different reference data from satellite, oceanographic databases, Biogeochemical Argo floats, literature. We demonstrate that the GODAE metrics paradigm can be efficiently applied to validate an operational model system for biogeochemical and ecosystem forecasts. The accuracy of the CMEMS biogeochemical products for Mediterranean Sea can be achieved from basin-wide and seasonal scale to mesoscale and weekly scale, and its level depends on the specific variable and the availability of reference data. In particular, the use of the Biogeochemical Argo floats data allows for a relevant enhancement of the validation framework of operational biogeochemical models, providing new skill metrics for key biogeochemical processes and dynamics (e.g. deep chlorophyll maximum depth), which can be easily implemented to routinely monitor the quality of the products and highlight any possible anomaly.