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Why we need supercomputers? |
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3. Ensemble calculations
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In this example of a forecast of the El Niņo event several forecast runs with slightly changed initial data, so called ensembles, are started. (Quelle ECMWF) |
Numerical models often react sensitively to slight disturbances of the initial data. For this reason the reliability of the models is sometimes questioned. The higher the computer performances become the more frequently ensemble calculations can be accomplished: The model computations are repeated many times with slight variations of the initial data so that random results can be distinguished from statistically proved trends.
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