[CF-metadata] new standard_name needed for cloud_phase (an enumeration type)

From: Jonathan Gregory <j.m.gregory>
Date: Fri, 19 Apr 2013 13:22:53 +0100

Dear Randy

> We are planning on using flags with numeric values as you suggest Your input is helpful in that is is deemed unnecessary to specifically identify values in the definition as is the case with the binary_masks, This provides additional flexibility to data producers.

Yes, exactly.

> standard_name: cloud_phase_category
>
> definition:
>
> A numeric value indicating one of the following categories: clear; liquid water; super-cooled liquid water; mixed phase; ice, and; unknown.

But it would be a string-valued quantity in principle, although netCDF does not
allow string-valued data variables. I think the definition should say

The variable is a string, taking one of the following values to indicate
cloud phase category: clear_sky, liquid_water, super_cooled_liquid_water,
mixed_phase, ice, unknown. For a data variable it is encoded as an integer
using flag_values and flag_meanings.

Comments on the values:

* clear_sky is a phrase already used in standard names. Could you use it
here for consistency?

* Is super_cooled_liquid_water a subset of liquid_water? If not, could you
give an extra adjective to liquid_water to clarify this?

Cheers

Jonathan
Received on Fri Apr 19 2013 - 06:22:53 BST