October 2025 monthly summary focused on correctness and reliability of the ocean model in FESOM/fesom2. Delivered a critical bug fix to metric_factor computation by setting metric_factor to zero per element in oce_mesh.F90, removing the previous tan(ay)/r_earth-based calculation and implementing the change per Qiang's suggestion. This correction improves simulation accuracy and stability, reducing risk of erroneous metric_factor values affecting results. The change is localized to oce_mesh.F90 and is ready for integration with the existing test suite and review. Overall impact: more reliable monthly runs, faster iteration cycles, and clearer guidance for users relying on metric_factor in model setup.

July 2025 (2025-07): Focused delivery of CO2 data outputs readiness in esm_tools. Implemented CO2 Output Enablement by updating XML template to allow CO2 mass mixing ratio and CO2 fluxes to be included in outputs. This work provides the foundation for enhanced CO2 analytics, model validation, and regulatory reporting, enabling more complete environmental data capture across pipelines.