EC-Earth3 and EC-Earth4 development and tuning
Title: EC-Earth3 and EC-Earth4 development and tuning
DNr: NAISS 2023/6-212
Project Type: NAISS Medium Storage
Principal Investigator: Paul Miller <>
Affiliation: Lunds universitet
Duration: 2023-07-01 – 2024-07-01
Classification: 10501 10507


EC-Earth3 and EC-Earth4 will continue to be central to earth system modelling (ESM) efforts in Sweden going forward, with Horizon Europe (HE) projects as well as the upcoming Coupled model intercomparison project CMIP7 being absolute priorities in the coming years. We ask to extend the duration of our current storage under project SNIC 2022/6-203 to continue test runs and development of EC-Earth3 and EC-Earth4 for the HE projects RESCUE (Start 1 Sep 2022, led by BSC in Barcelona) and OptimESM (Start 1 Jan 2023, led by SMHI). As described in the report, this storage space is crucial to allow for tuning, comparison with previous versions, and evaluation runs as well as storage of model input and output.