Slayt 1 - RTC, Regional Training Centre - Turkey

Impacts of Grid Point Physics Calculations inSpectral ModelsFor the grid point calculations, thevalues of the forecast variables mustbe transformed from spectralrepresentation to grid points. Theexact location and spacing of the gridpoints is determined by the model's"resolution" (maximum number ofwaves). The location and spacing ofpoints is chosen to closely match themodel's spectral resolution (maximumwave number) and most accuratelycalculate the non-linear dynamicterms. However, since model physicsare also calculated on this grid,problems can result when the localeffects of physics introduce errorsduring the transformation from gridpoint back to spectral representation.The graphic illustrates the process forcalculations done on the grid inspectral models.