CDO

Hi,

I'm using cdo collgrid to merge several netCDF files into one. The input files are produced by the DALES LES model. DALES tags its output files with the model version and git commit hash, in the Source attribute. I noticed that this attribute is lost when merging the files using cdo. Can this be fixed in cdo, or are we using the Source attribute wrong? (one guess: does capitalization matter? I saw in the CF specifications that the attribute is called source).

Example (using cdo 2.0.4):

cdo -f nc4 -r -O collgrid cape*.nc merged-cape.nc

ncdump -h cape.x000y000.001.nc
--cut--
// global attributes:
        :title = "cape.x000y000.001.nc" ;
        :history = "Created on 20220623 at 131653.152" ;
        :Source = "DALES 4.4 git: v4.4" ;
        :Author = "" ;

ncdump -h merged-cape.nc
--cut--
// global attributes:
        :CDI = "Climate Data Interface version 2.0.4 (https://mpimet.mpg.de/cdi)" ;
        :Conventions = "CF-1.6" ;
        :title = "cape.x000y000.001.nc" ;
        :history = "Thu Jun 23 13:19:26 2022: cdo -f nc4 -r -O collgrid cape.x000y000.001.nc cape.x000y001.001.nc merged-cape.nc\nCreated on 20220623 at 131653.152" ;
        :CDO = "Climate Data Operators version 2.0.4 (https://mpimet.mpg.de/cdo)" ;

In the cdo output, the Source and Author attributes are gone.

Best regards,
Fredrik Jansson