Added fix to convert "geopotential" to "geopotential height" for ERA5

[egalytska]

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This pull request is related to ESMValTool pull request ESMValGroup/ESMValTool#1644.

[bouweandela]

@valeriupredoi Would you be able to test this and help with adding a unit test?

[valeriupredoi]

I will add a unit test in a jiffy but can't test since we don't have any ERA5 data on Jasmin - @mattiarighi is the ERA5 landlord at DKRZ 😁

[bouweandela]

I will add a unit test in a jiffy but can't test since we don't have any ERA5 data on Jasmin

@valeriupredoi Here is a blog post announcing the availability of ERA5 on Jasmin. It is stored in /badc/ecmwf-era5 and /badc/ecmwf-era5t

[valeriupredoi]

dam right you are it's there, had no idea! But am gonna need a manual to be able to understand what's the data paths - do we have this location anywhere in the documentation and some instructions on how to grab files depending what one needs?

[bouweandela]

There is some documentation here: https://confluence.ecmwf.int/display/CKB/ERA5%3A+data+documentation#ERA5:datadocumentation-DataorganisationandhowtodownloadERA5, click Data organisation in MARS to expand the tab to have an explanation of the facets.