In June 2025, Sabine Griessbach from Jülich Supercomputing Centre (FZJ) will join us at the HiRSE Seminar Series to talk about ‘Leveraging Earth System Science to Exascale’ and the German National Earth System Modelling Support Team. Abstract: Modeling the Earth system is a complex, multidisciplinary endeavor encompassing various domains including the atmosphere, ocean, land surface, biosphere, ice sheets, and chemistry. In Germany, numerous research institutions actively work on Earth system modeling (ESM). ESM covers a wide range of spatial and temporal scales — from molecular interactions to global phenomena, and from hourly weather forecasts to paleo-climatic changes spanning millennia. The national Earth System Modeling project (natESM) aims to integrate these diverse modeling efforts. An important aspect is preparing the models for exascale computing. Therefore, the German Climate Consortium (Deutsches Klima-Konsortium) has established a national ESM support team, funded by the German Federal Ministry for Education and Research. This support team, coordinated by the Deutsches Klimarechenzentrum (DKRZ) in Hamburg, plays a key role in the German strategy for advancing ESM capabilities. Its main objective is to bring together the German ESM community and enable the coupling of individual model components into more comprehensive, interoperable Earth system models. The support team is comprised of four research software engineers based at DKRZ and the Jülich Supercomputing Centre (JSC). Through support sprints lasting up to six months, the team provides assistance to German ESM developers for adapting ESM codes to modern high-performance computing (HPC) architectures and facilitating model coupling. Participation in the natESM project requires that all supported codes are open source. ESM developers can apply for support through a continuously open rolling call. Knowledge and insights gained during the support sprints are shared through dedicated workshops and targeted trainings. Experience from the first three years of the project and an outlook to the hopefully upcoming second phase will be given. The presentation recording is available on the HiRSE YouTube Channel: https://www.youtube.com/watch?v=o-ad8pB8hrs Learn more about the HiRSE Seminar Series: https://www.helmholtz-hirse.de/series.html