Exploring ocean-atmosphere-land interactions at km-scale resolutions with IFS-FESOM/NEMO

Montag 19.02.2024, 11:00 → 12:00 Europe/Berlin

8A-002 - Hörsaal Ostufer / Lecture Hall East (GEOMAR - Standort Ostufer / GEOMAR - East Shore)

Speaker: Dr. Thomas Rackow,  European Centre for Medium-Range Weather Forecasts (ECMWF)

Hybrid  and Zoom: https://geomar-de.zoom.us/j/84289388604?pwd=dGlpeTBUd1Nxem5Ec3dRYXh4NFpOUT09

Abstract     
The ocean-sea ice system plays a crucial role in the Earth's climate, but its representation in global models is often limited by coarse resolutions, parameterisations, and long-standing biases. Coupling ECMWF’s Integrated Forecasting System (IFS) with the Finite VolumE Sea ice-Ocean Model (FESOM2.5) and the Nucleus for European Modelling of the Ocean (NEMO) allows for simulating ocean-atmosphere-land interactions at km-scale resolutions (4.4km and better), resolving important processes such as mesoscale eddies, sea ice leads, and urban effects. In this talk, I will present some of the first multi-year global simulations performed with this coupled system, as part of the Next Generation Earth Modelling Systems (nextGEMS) project, and touch on the related Destination Earth initiative (DestinE). I will discuss the technical and scientific challenges involved in developing and running such high-resolution models, as well as the main improvements achieved in terms of conservation properties, top-of-the atmosphere radiation balance, precipitation characteristics, and ocean dynamics. Finally, I will show some first examples of the enhanced realism and skill of these simulations, highlighting the impacts of km-scale features on the climate system.