Scientific developments of IFS-NEMO for Destination Earth’s Climate Adaptation Digital Twin

The Climate Adaptation Digital Twin within the Destination Earth project represents an innovative initiative aimed at achieving operational kilometer-scale global climate simulations to support climate adaptation efforts. Three state-of-the-art Earth System Models (ESMs) are used separately and we are focusing on the scientific advancements and simulation results of the IFS-NEMO model throughout the project's duration.

During the first phase of the project, two main simulations were produced: a historical experiment (1990–2019) at 10 km resolution, and a SSP3-7.0 scenario (2020–2039) at 5 km resolution. Phase 2 aims to enable the operationalization of these simulations. Analysis of phase 1 IFS-NEMO results revealed a notable cold bias in the model’s mean state. To address this issue, a newly tuned version of the model was developed, significantly reducing the cooling trends. Key adjustments to achieve this improvement, first tested at a 25 km resolution version of the model, included refinements to sea-ice parameterization within the NEMO model,  and the introduction of MACv2-SP forcings in IFS, which enabled the representation of time-varying aerosols in the future scenarios. Additional enhancements were made to couple the river runoff to the ocean.

The outcomes of these efforts highlight the potential for substantial advancements in global climate modeling. Looking ahead, the integration of kilometer-scale simulations into operational workflows promises to deliver unprecedented detail and accuracy in climate projections. This will enable more precise assessments of climate impacts and provide critical insights for policymakers and stakeholders striving to implement effective climate adaptation strategies. The continued refinement of the IFS-NEMO model and its components will play a pivotal role in achieving these ambitious goals.