Parallel implementation of a meteorological model on a SIMD architecture

The implementation of the Meteorological Limited Area. Model BOLAM on Quadrics, a SIMD massively parallel computer, is discussed. BOLAM is an explicit, primitive equations, hydrostatic, three-dimensional grid point model. The parallel version of this code, QBOLAM, will be one of the components of an integrated numerical system for the prediction of the state of the Mediterranean Sea. The performances of the dynamical core of QBOLAM are presented here. A maximum performance of 8.7 GFlops sustained, corresponding to 34 % of the peak power, is measured on the 512 nodes machine. In the operational configuration (10 km grid spacing, over an area of 8.10(6) km(2), 40 vertical levels, 128 nodes machine), the code reaches 2.1 GFlops sustained.