add pressure levels to long name

[larsbuntemeyer]

Standard names must follow those defined by CF, and these represent the physical quantity. Other aspects, such as the level, are represented by other metadata of the variable (such as a scalar coordinate variable representing the pressure level). So standard_names are OK even if repeated for many different variables.

Long names are not critical as these are just free text descriptions. However, you spotted a clear inconsistency between the variable and the corresponding metadata, so this should be fixed. I let the PR open, just in case you found some others.

Long names without much detail are no problem, in principle. For pressure level data we could include the level explicitly, though. E.g. in CMIP6 they do include it:
https://github.com/PCMDI/cmip6-cmor-tables/blob/80d2e4b606555720630a61389cfe3b5cb8f43746/Tables/CMIP6_6hrPlev.json#L312

@larsbuntemeyer @gnikulin what do you think?

Originally posted by @jesusff in #39 (comment)