Workshop on software strategies for sustainable physical modelling
Keynote speakers
Daan Degrauwe (RMIB)
Presentation: Porting of the ICE3 microphysics to PMAP
Dr. Georgiana Mania is a Research Software Engineer at the German Climate Computing Center in Hamburg, Germany. Her research focuses on achieving performance portability of the weather and climate model ICON, exploring parallel programming languages, and redesigning the code to enable kilometer scale simulations. In addition to her research, Georgiana contributes to academic teaching activities at the University of Hamburg and Magdeburg and delivers tutorials at various events. Georgiana completed her PhD in High-Performance Computing on heterogeneous architectures for High-Energy Physics simulations at the University of Hamburg in 2023. Prior to pursuing her academic career, she gained industry experience in software engineering. Georgiana holds an Engineering Degree in System Engineering and Computer Science from the University Politehnica of Bucharest.
Presentation: Enabling Performance Portability in ICON with C++/Kokkos: The Ragnarok Approach
Abstract: Modern supercomputers provide unprecedented opportunities for high resolution weather and climate simulations, but their increasingly heterogeneous CPU–GPU architectures pose major challenges for Earth system models. To efficiently exploit these systems, legacy Fortran-based codes must evolve toward performance-portable, maintainable, and scalable software architectures. Within the Ragnarok project, we are transitioning the ICON model from Fortran to modern C++ using the Kokkos programming model to achieve performance portability across current and emerging high performance computing platforms. Our approach follows an incremental rewrite strategy that enables interoperability between legacy Fortran components and newly developed C++ modules, allowing continuous scientific production while modernizing the code base. The initial focus is on the AES physics components used in kilometre-scale climate simulations.
Alongside the migration effort, we are establishing a comprehensive software engineering framework including automated unit and integration testing, code formatting, and linting to ensure correctness, maintainability, and long-term sustainability. This presentation will discuss the architecture and technical design of Ragnarok within ICON, the challenges encountered during the transition process, and first results demonstrating performance and portability
across heterogeneous HPC architectures.
Philippe Marguinaud (Météo-France)
Presentation: Refactoring ARPEGE/IFS for porting to GPU accelerators
David Simonin (Met Office)
Presentation: TBC
Yannick Trémolet (JCSDA)
Presentation: Flexible strategies for future data assimilation