Opportunities and Challenges in Weather and Climate Modelling: Experiences from the Destination Earth Initiative

Weather and climate modelling are at a transformative moment, driven by rapid advances in machine learning (ML) and artificial intelligence (AI), access to extreme-scale supercomputing, and the development of very high-resolution Earth system models. These advances offer new opportunities to improve predictions of extreme events, explore future climate scenarios, and provide more tailored information to users. At the same time, they bring new scientific, technical, and operational challenges — from model development and verification to efficient deployment on emerging computing architectures.

The European Commission’s Destination Earth (DestinE) initiative addresses some of these challenges and opportunities through a large-scale collaborative European effort. DestinE is implemented by ECMWF, ESA and EUMETSAT, together with many partners across Europe, under the lead of EC's DG CNECT. DestinE is building Digital Twins of the Earth system — interactive, high-resolution simulations that combine advanced modelling, Earth observations, and emerging AI methods, leveraging the EuroHPC world class supercomputers. These Digital Twins enable the exploration of “what-if” scenarios and provide detailed information to support adaptation and response to extreme weather and climate events.

In this contribution, we will present key experiences from DestinE, focusing on successes and challenges in building the Digital Twin Engine, the first two Digital Twins on weather-induced extremes and climate change adaptation, as well as efforts to develop an ML-based Earth system model. We will discuss how these developments, led by ECMWF and over 100 partner institutions across Europe, push the boundaries of modelling capabilities, while explicitly aiming to complement existing national and European capabilities and services.

An important aspect of DestinE is its effort in bringing weather and climate modelling closer together. Many of the scientific and technical challenges — related to high-resolution modelling, verification, exploitation of Europe's largest supercomputers and AI integration — are shared across timescales. DestinE provides a framework to address these challenges in a coordinated way, helping to advance Europe’s capability to respond and adapt to environmental extremes, and supporting national authorities in their role to protect lives and assets from extreme events and climate change.