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Forcing data have to be in netCDF (standard CF-1.0 formatted) or GRIB format. Maximal resolution in time recommended for boundary data is 6 hours. Following Denis et al. (2003) a factor of 12 in the horizontal resolution between the forcing data and the resolution of the regional simulation which should be performed is the maximum. Further information on requirements of the data can be found in Part V of the COSMO documentation.
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