Medium-range weather forecast on parallel systems

GMD and ECMWF (European Centre for Medium-Range Weather Forecasts) joined forces in autumn 1992 in order to parallelize the Integrated Forecasting System (IFS), that is run operationally each day for the European medium-range weather prediction. The parallelization is performed in a portable way with all relevant parallel systems as target machines. Meanwhile, the parallelization of the 3D weather model has been achieved: the code runs with excellent parallel efficiencies of 90% and more on different parallel systems such as the SP1 (IBM) and the CM5 (Thinking Machines). First optimizations promise significant further improvements.<>