Valentin Clement from the Center for Climate System Modeling in Switzerland gave this talk at PASC18. ‘In order to profit from emerging high-performance computing systems, weather and climate models need to be adapted to run efficiently on different hardware architectures such as accelerators. This is a major challenge for existing community models that represent very large code bases written in Fortran. We introduce the CLAW domain-specific language (CLAW DSL) and the CLAW Compiler that allows the retention of a single code written in Fortran and achieve a high degree of performance portability.”