Periodic Reporting for period 2 - EERIE (European Eddy-RIch ESMs)
Período documentado: 2024-05-01 hasta 2025-09-30
A central achievement of RP2 has been the successful production of the first coordinated, multi-model set of century-scale, fully coupled eddy-rich climate simulations, including kilometre-scale atmosphere (~9 km) and eddy-rich ocean resolutions. These simulations were completed across several modelling systems and now form the backbone of scientific analysis in WPs 5–12.
To enable efficient exploitation of these unprecedented datasets, EERIE established a modern, scalable and FAIR data ecosystem. Phase-1 outputs were quality controlled, standardised and published through ESGF, CEDA and WDCC, with additional fast access via eerie.cloud using Zarr, STAC catalogues and virtual datasets. Integrated visualisation and analysis tools substantially reduce time-to-science and support ML workflows.
Scientific evaluation during RP2 shows that EERIE models realistically capture key characteristics of the ocean mesoscale while identifying systematic weaknesses in regions with complex dynamics. These insights directly informed a refined Phase-2 strategy, shifting towards small ensembles of eddy-rich simulations to robustly quantify uncertainty and internal variability.
Further achievements include demonstrable improvements in large-scale circulation, air–sea coupling and the simulation of high-impact events, significant gains in computational efficiency, and the delivery of the first stable hybrid coupled climate model combining a dynamical ocean with an ML-based atmosphere.
For the first time, multi-decadal to century-scale, fully coupled eddy-rich climate simulations are available across multiple independent ESMs. Earlier studies were limited to short integrations, single models or uncoupled configurations. EERIE therefore enables robust assessment of how ocean mesoscale processes influence climate variability, extremes, circulation changes and potential tipping behaviour.
The project demonstrates that explicitly resolving mesoscale dynamics leads to systematic improvements in large-scale circulation features, coastal sea-surface temperatures, water-mass pathways and air–sea interaction processes that directly affect regional climate and extremes. EERIE further shows that mesoscale impacts on the atmosphere arise primarily through indirect pathways linked to heat and freshwater transports, refining long-standing hypotheses with quantitative evidence.
By resolving mesoscale-driven variability, EERIE improves estimates of background natural variability, a prerequisite for reliable regional climate attribution and risk assessment. This represents a substantial advance over conventional CMIP-class models.
Methodologically, EERIE introduces novel experimental designs extending CMIP capabilities, including ensemble-based eddy-rich strategies and targeted sensitivity experiments. Through leadership of the HighResMIP2 design for CMIP7, EERIE is shaping next-generation global high-resolution intercomparisons. The integration of eddy-rich simulations with ML-based emulators and hybrid models opens new pathways to deliver high-fidelity climate information at manageable computational cost.