NCL Home> Application examples> Models || Data files for some examples
REMO is a regional climate model created as a joint effort by several German reserach groups (eg: MPI for Meteorology, DKRZ, DWD, GKSS). A primary focus is concentrated on the hydrological components of the water cycle.
The output format is GRIB. Users should examine the file's contents prior to use via ncl_filedump withe the -itime option:
ncl_filedump -itime REMO.grb | lessIn addition to the output one normally sees from ncl_filedump, eg:
float P_WAT_GDS0_SFC ( initial_time0_hours, g0_lat_1, g0_lon_2 ) long_name : Precipitable water units : kg/m^2 _FillValue : 1e+20 level_indicator : 1 gds_grid_type : 0 parameter_table_version : 128 parameter_number : 54 forecast_time : 0 forecast_time_units : hoursIt is likely that the user will see warning messages like:
warning:NclGRIB: Unknown grib parameter number detected (129, center 0, table version 128 grib record 1), using default variable name (VAR_129) warning:NclGRIB: Unknown grib parameter number detected (130, center 0, table version 128 grib record 30), using default variable name (VAR_130) warning:NclGRIB: Unknown grib parameter number detected (134, center 0, table version 128 grib record 2), using default variable name (VAR_134) warning:NclGRIB: Unknown grib parameter number detected (172, center 0, table version 128 grib record 3), using default variable name (VAR_172) warning:NclGRIB: Unrecognized parameter table (center 0, subcenter 0, table 128), defaulting to NCEP operational table for standard parameters (1-127): variable names and units may be incorrect [SNIP] float VAR_130_GDS0_HYBY ( initial_time0_hours, lv_HYBY3, g0_lat_4, g0_lon_5 ) long_name : Unknown Variable Name units : unknown _FillValue : 1e+20 level_indicator : 110 gds_grid_type : 0 parameter_table_version : 128 parameter_number : 130 forecast_time : 0 forecast_time_units : hours [SNIP]The reason for these warning messages is that NCL does not have a valid builtin GRIB table that allows NCL to lookup the variable name and units associated with the GRIB file's parameter id. A sample REMO GRIB table is available: REMO3_WRF_Vtable. However, the information needed to correctly apply the table is not present. As noted by one of the NCL developers:
It is not going to be possible to support the REMO GRIB table as long as they are putting out 0 for the center id. 0 is not a recognized center id, so there is no valid way to identify where the GRIB file is coming from.IMPORTANT NOTE: THE DATA VALUES ARE CORRECTLY UNPACKED. However, the user must manually provide the appropriate information by looking at the REMO GRIB table. See Example 2.
remo_1.ncl: Read and plot a variable from a REMO file.
remo_2.ncl: Read a variable for which a warning message was issued and manually add meta data by looking at REMO3_WRF_Vtable. Here "VAR_130" is read and level 25 is plotted. Note there is no information to indicate the actual level used.