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Use ncclimo if possible. It requires and comes with NCO version 4.6.0 and later. Its predecessor climo_nco.sh (which is deprecated) requires NCO version 4.5.2 or later. The newest versions of NCO are installed on rhea/titan.ccs.ornl.gov at ORNL, pileus.ornl.gov (CADES at ORNL), cooley/mira.alcf.anl.gov at ANL, cori/edison.nersc.gov (NERSC), aims4.llnl.gov (LLNL), roger.ncsa.illinois.edu (NCSA), and yellowstone.ucar.edu (NCAR). The ncclimo and ncremap scripts are hard-coded to find the latest versions automatically, and do not require any module or path changes. To use other (besides the ncclimo and ncremap scripts) NCO executables from the command-line or from your own scripts may require loading modules. This is site-specific and not under my (CZ's) control. At OLCF, for example, "module load gcc" helps to run NCO from the command-line or scripts. For other machines check that the default NCO is recent enough (try "module load nco", then "ncks --version") or use developers' executables/libraries (in ~zender/[bin,lib] on all machines). Follow these directions (on the NCO homepage) to install on your own machines/directories. It can be as easy as "apt-get install nco", "dnf install nco", or "conda install nco", or you can build from scratch with "configure;make install".
The older version of ncclimo is climo_nco.sh which is distributed separately from NCO, and therefore cannot be as tightly coupled to new NCO features. The two are still nearly interchangeable so all documented features (except where indicated otherwise) apply to both. You can obtain the deprecated script at https://github.com/ACME-Climate/PreAndPostProcessingScripts/blob/master/generate_climatologies/climo_nco.sh or check-out the entire PreAndPostProcessingScripts Git repo (a better option for keeping up-to-date with changes to this script) with "git clone https://github.com/ACME-Climate/PreAndPostProcessingScripts.git". Sometimes this works better: "git clone git@github.com:ACME-Climate/PreAndPostProcessingScripts.git". Here's the ACME Git Tutorial. If you have permissions problems, try this: https://help.github.com/articles/generating-ssh-keys/.
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