Reorganizing observational datasets on HPCs

[rswamina]

A discussion about organizing observational datasets on the HPC machines raised the following items:

1. Having ready to use, CMOR-ized for ESMValTool obs data sets is very highly valued especially by new users.
2. Currently data are under Tiers 1-3 depending on whether they are free to download and use, have access restrictions etc.
3. Tier1 data are all Obs4MIPs at this time.
4. Obs4MIPs data can now be downloaded from ESGF through ESMValTool and has its own directory path (different to current Tier1 set up). It was suggested that it would be best to keep this path just like for CMIP data.
5. It was suggested that the OBS datasets which are currently CMOR-ized with ESMValTool also potentially follow the Obs4MIPs directory structure as much as possible. This would include adding a version (possibly date of CMOR-ization) subdirectory.
6. It was agreed on that the current set up will continue to remain while changes are debated and implemented as and when possible so things don't break in transition.