[CF-metadata] More canonical units or more standard names?

From: Jonathan Gregory <j.m.gregory>
Date: Wed, 17 Apr 2013 09:31:01 +0100

Dear Ted

> In terms of the standard_names options you have proposed, I
> personally prefer:
>
> toa_outgoing_spectral_radiance_per_unit_wavelength
> units: mW m-2 sr-1 um-1
>
> toa_outgoing_spectral_radiance_per_unit_wavenumber
> units: mW m-2 sr-1 (cm-1)-1
>
> toa_outgoing_spectral_radiance_per_unit_frequency
> units: W m???2 sr???1 Hz???1
>
> though I wonder why you choose mW for two and W for the other. (This
> is a secondary issue - not really of central importance.)
>
> So for those who have gotten this far, in this response, I hope we
> can reach consensus on the debate of 1 versus 3 standard names for
> the different flavors of toa_spectral_radiance. I think it depends
> on the central issue that if the quantity is a function of the units
> of the > coordinate variable, then does a change in the coordinate variable
> units imply a unique physical quantity and therefore a unique
> standard_name.

Yes, it does. Different *canonical* units always mean different standard names
in the CF standard name table. That is, the identification of the quantity does
not depend on the units.

However, any units which are have the same physical dimensions as the canonical
units are acceptable. For definition of standard names, it doesn't matter
whether W or mW are used as canonical units, for example.

Cheers

Jonathan
Received on Wed Apr 17 2013 - 02:31:01 BST