We present the first digital twin framework that operationalizes the production of multi-decadal, global climate projections at kilometre-scale resolution, developed within the European Union’s Destination Earth initiative. Using three coupled Earth system models and selected impact-sector applications, we have built end-to-end workflows for both regular and on-demand climate projections on two EuroHPC supercomputers, LUMI and MareNostrum5. These workflows produced the first-ever multi-decadal simulations at 5 km resolution across all major Earth system components, using the same output parameters and grid, and achieving a production throughput of 0.6 simulated years per day and a climate data portfolio of 6.6 petabytes. We demonstrate the scalability of two of these Earth system models across both CPU and GPU-based systems at global resolutions up to 1 km, across atmosphere, ocean, land, and sea-ice, and report record-breaking full-machine performance on LUMI and MareNostrum5 of up to 97 simulated days per day at 1 km resolution.

We are making available a multi-petabyte data set for open science via a data hackathon. The participants bring their science to the computing and data facility, alleviating the need to transfer and manage the large volume of data. This accelerates the process of discovery science while increasing scientific throughput.