Development of high-resolution Earth system models for global and regional climate change projections Projects should foster a fully coupled atmosphere-ocean-land-ice Earth-system model approach that contributes to a better understanding and representation of the processes, including for that drive and influence climate change on global and regional scale. Arctic and Antarctic regions should be considered as key elements in global climate changes.Projects should make efficient use of available and high quality observational data (e.g. space-based and not space based, including in-situ and paleoclimatic data) for the development of robust model validation, verification, and improve uncertainty estimation methodologies.Where relevant, high-resolution model development and evaluation should be properly connected with major programmes in the domain of Earth Observation such as the Copernicus Programme, the ESA science satellite missions in Europe, as well as the Group on Earth Observations (GEO) and the Global Earth Observation System of Systems (GEOSS) at global level.They should also strive to reduce uncertainty of key parameters of climate and hydrological systems. Projects should advance methods for assessing and attributing model outputs and climate change impact on regional scales with the support of advanced digital technologies, such as artificial intelligence methodologies.The advanced climate modelling activities should support the attribution of observed and projected climatic hazards to climate change or climate variability.The activities should build on the experiences from and results of other European projects contributing to the development of a new generation of climate models[[E.g. H2020 CRESCENDO (Coordinated Research in Earth Systems and Climate: Experiments, kNowledge, Dissemination and Outreach) https://cordis.europa.eu/project/id/641816 , H2020 PRIMAVERA (PRocess-based climate sIMulation: AdVances in high resolution modelling and European climate Risk Assessment) https://cordis.europa.eu/project/id/641727, or projects funded from the call topic H2020-LC-CLA-18-2020.]].Beneficiaries are encouraged to take advantage of the emerging ICT infrastructures (e.g. EuroHPC and other high performance computing, cloud-based facilities) that will be made available through the Destination Earth initiative under the Digital Europe Programme[[https://ec.europa.eu/digital-single-market/en/europe-investing-digital-digital-europe-programme]].If adding value to the project outcomes, coordination with the Destination Earth initiative can be proposed to ensure the timely development of “climate replicas” building on the new state-of-the-art IT infrastructure, including access to European high performance computing resources and an operational platform to upload and integrate the models and data developed in the course of the projects. Connection to the European Open Science Cloud (EOSC) should be considered where relevant.When dealing with models, actions should promote the highest standards of transparency and openness, as much as possible going well beyond documentation and extending to aspects such as assumptions, code and data that is managed in compliance with the FAIR principles[[FAIR (Findable, Accessible, Interoperable, Reusable). Further information: https://www.go-fair.org/fair-principles/; and Final Report and Action Plan from the European Commission Expert Group on FAIR Data, “TURNING FAIR INTO REALITY” (https://ec.europa.eu/info/sites/info/files/turning_fair_into_reality_0.pdf) ]]. In particular, beneficiaries are strongly encouraged to publish results data in open access databases and/or as annexes to publications. In addition, full openness of any new modules, models or tools developed from scratch or substantially improved with the use of EU funding is expected.International cooperation is encouraged.Projects are expected to co-operate with other projects funded under this call, as well as other relevant projects under Destination 1 and Cluster 6, Destination 5.