[las_users] netcdf4-file access via THREDDS server corrupts data

[Martin Schmidt <martin.schmidt@xxxxxxxxxxxxxxxxx>]

Hi,
I am not really sure, if the error report should go to the ferret or the 
las - list.

I have put a file with model results on a THREDDS server and find, that 
some area with existing data is blanked out.

ferret
yes? set data 
"http://phy-51.io-warnemuende.de/thredds/dodsC/baltic/region_test_2005_netcdf4.nc";
 *** NOTE: Units on axis "nv" are not recognized: none
 *** NOTE: They will not be convertible:
yes? shade/x=16/l=10 temp

shows the problem. Accessing the same file directly, shows a complete 
picture.

The file was generated originally from mom4 (netcdf3) and transformed to 
netcdf4 by nccopy -d3 -k3.
Unfortunately, the original file was deleted to save disk space.

Copying again with reduced compression gives the same error.

Transforming back to netcdf3 and putting the file at the THREDDS server 
gives correct output.
yes? set data 
"http://phy-51.io-warnemuende.de/thredds/dodsC/baltic/region_test_2005_netcdf3.nc";
 *** NOTE: Units on axis "nv" are not recognized: none
 *** NOTE: They will not be convertible:
yes? shade/x=16/l=10 temp

Several ferret versions (6.72, 6.82) show the same error.

I would prefer to keep the data in netcdf4 format. Any idea how to fix 
this problem, is very welcome.

Thanks in advance,
Martin Schmidt