## WebPEP Domain related error in INT2LM read_nc_gdefs_ext_lm

Hi there,

currently I’m trying to run COSMO with a slightly different domain compared to EURO-Cordex. So I used WebPEP to create a domain which is just one grid point larger at the western boundary. But then INT2LM - fed with the EXTPAR-File - returns an error:

OPEN: ncdf-file: .../DOMAINS/europe-022_w+1.nc   external data file        namelist input ie_ext              233                 233 je_ext              226                 226 lonll        -30.7399997711182               -30.7400000000000      latll        -25.5200004577637               -25.5200000000000      lonur         20.2999992370605                20.3000000000000      latur         23.9799995422363                23.9800000000000      dlon         0.219999995724908               0.220000000000000      dlat         0.220000000000000               0.220000000000000      pollat        39.2500000000000                39.2500000000000      pollon       -162.000000000000               -162.000000000000      polgam       0.000000000000000E+000          0.000000000000000E+000 wrong grid for LM external parameters

This error I do not understand. It looks like an rounding issue. Or INT2LM seems to be especially picky about rounding error.
Here is the link to my WebPEP session: http://www.clm-community.eu/web_pep/domains/domain2017031409012/

Cheers, Klaus

### Replies (2)

#### RE: WebPEP Domain related error in INT2LM read_nc_gdefs_ext_lm - Added by Hans-Juergen Panitzabout 1 year ago

Hi Klaus,

I am not quite sure whether I understand correctly what you did.
Your "target" domain size for the CCLM run is 233*226 (ie_ext*je_ext),isn’t it?
And you have chosen the identical domain and size for the external data set, haven’t you?
To see the file INPUT of INT2LM would be helpful.

If you did it in this way, then INT2LM would never run.
The size of the domain of external data has to be larger then the size of the actual CCLM domain.
I am not quite sure, but at least by 2 further grid points at each of the four sides.

I always recommend to chose the domain of the external data set rather large. Then you can "play" with
the size of the CCLM domain, with shifts of start_lon and start_lat, etc. without creating new external data sets.

Hans-Juergen

#### RE: WebPEP Domain related error in INT2LM read_nc_gdefs_ext_lm - Added by Klaus Pankatzabout 1 year ago

Hi Hans-Jürgen,

thanks for the information. I didn’t have in mind, that the EXTPAR dataset has to be on a enlarged grid compared to the COSMO domain.
Now the error message makes sense.

Klaus

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