Minisymposium Presentation

Exploiting GPUs is both an opportunity and a challenge for weather and climate codes. They present an opportunity as the massive parallelism they possess can allow these codes to achieve very high computational performance. They present a challenge as exploiting this parallelism can require the refactoring of many thousands of lines of science code and a new programming model from existing CPU code bases. In this presentation, we will describe the development of the GPU-enabled cloud microphysics scheme - CASIM and radiation scheme - SOCRATES, and a Domain Specific Language the Met Office is using to achieve performance portability for its new weather and climate model, LFRic and the wider modelling system known as Momentum. We will show how the Met Office is using PSyclone, a Domain Specific Compiler to keep single source science code whilst targeting multiple programming models for different processor architectures. The presentation will conclude the strategy and progress for porting and optimizing Momentum for GPUs, and how PSyclone follows the porting experience of ORNL to optimize CASIM and SOCRATES on GPUs.