CDO

Hi Nick. I doubt it. However, without an uploaded sample file (i.e. use cdo seltimestep,1 infile outfile), no one can help you with this question. (FYI: The first google for GFS (for me) is "Gordon Food Service". I guessed you meant "Global Forecast System"...). So upload a sample and post your exact command line. The more information you provide, the better the chance someone may be able to help you.

Hello,

Thanks. I suspect it isn't possible, but ...

An example - this file

https://nomads.ncep.noaa.gov/pub/data/nccf/com/gfs/prod/gfs.20221128/00/atmos/gfs.t00z.atmf000.nc

cdo:

cdo -f grb2 ml2pl,100000,92500,85000,80000,70000,60000,50000,30000,25000,20000,15000,10000 -selname,ugrd,vgrd gfs.t00z.atmf000.nc test.grb

gives this:

Warning: No 3D variable with hybrid sigma pressure coordinate found!

I just wondered if there was a way ...

Hm, that is a large file. Can you upload only one time step.

Thanks for looking. Each is a time step.

That is just how large NOAA makes them.

Hi Nick,

as Karin and Brendan mentioned that file is too big to download, and do a fast checking. Note that the problem is cdo cannot find the hybrid sigma pressure. You should check the attributes for that file, or extract a section of the original file with all the vertical points -or even a single point. cdo is really peaky about cf convenctions.

Kind regards,

Estanislao