Toward Exascale Climate Modelling: A Python DSL Approach to ICON’s (Icosahedral Non-hydrostatic) Dynamical Core (icon-exclaim v0.2.0)

作者：Anurag Dipankar, Mauro Bianco, Mona Bukenberger, Till Ehrengruber, Nicoletta Farabullini, Abishek Gopal, Daniel Hupp, A. Jocksch, Samuel Kellerhals, Clarissa Kroll, Xavier Lapillonne, Matthieu Leclair, Magdalena Luz, Christoph Müller, Chia Rui Ong, Carlos Osuna, Praveen Kumar Pothapakula, Matthias Röthlin, William Sawyer, Giacomo Serafini, Hannes Vogt, Ben Weber, T. C. Schulthess · 年份：2025 · DOI：10.5194/egusphere-2025-4808 · 被引用次数：4 · 研究领域：Geophysics and Gravity Measurements

Abstract. A refactored atmospheric dynamical core of the ICON model implemented in GT4Py, a Python-based domain-specific language designed for performance portability across heterogeneous CPU-GPU architectures, is presented. Integrated within the existing Fortran infrastructure, the GT4Py core achieves throughput slightly exceeding the optimized OpenACC version, reaching up to 213 simulation days per day when using a quarter of CSCS’s ALPS GPUs. A multi-tiered testing strategy has been implemented to ensure numerical correctness and scientific reliability of the model code. Validation has been performed through global aquaplanet and prescribed sea-surface temperature simulations to demonstrate model’s capability to simulate mesoscale and its interaction with the larger-scale at km-scale grid spacing. This work establishes a foundation for architecture-agnostic ICON global climate and weather model, and highlights poor strong scaling as a potential bottleneck in scaling toward exascale performance.