Concatenate netcdf files with different variables - using nco

Question

I want to concatenate two sets of netcdf files using nco, where each set has about 30 files.

Set 1 contains: longitude, latitude, time and v.

Set 2 contains: longitude, latitude, time and u.

I have tried:

ncks *.nc out.nc

but I get:

Error received 97 filenames; need no more than two

then I tried:

ncks -A *.nc out.nc

but the error persists:

Error received 97 filenames; need no more than two

Please can you point me in the right direction, I am quite new to this.

Thanks in advance.

score 3 · Accepted Answer · answered Sep 30 '19 at 20:28

3

Your first try should work if you use ncrcat instead of ncks:

ncrcat *.nc out.nc

And be careful that your wildcard expression evaluates to the files you intend, i.e., that ls *.nc results in all input files and nothing else.

answered Sep 30 '19 at 20:28

Charlie Zender

My apologies for only getting back to you now @Charlie Zender, but I have been out of office. There seems to be a problem with the data on my side, so I will accept this answer. – Goose_08 Oct 03 '19 at 05:04
This would work on each set separately but not with a mixture of them. Attempt to merge files with different variables leads to ERROR: nco_inq_varid() reports requested variable "XXX" is not defined in file – Roux Jan 13 '21 at 16:37

score 3 · Answer 2 · edited Apr 21 '22 at 07:42

3

As an alternative you can also use Climate Data Operators (CDO):

cdo cat *.nc out.nc

assuming all files are on the same grid and times.

edited Apr 21 '22 at 07:42

Luke Davis

answered Oct 01 '19 at 05:55

ClimateUnboxed

2 Answers2