[CF-metadata] Duplicate vocabulary attenuation/extinction and backscatterin/backwards_scattering.

From: Jonathan Gregory <j.m.gregory>
Date: Mon, 12 Mar 2012 13:14:22 +0000

Dear Philip

> 1) _attentuation_ and _extinction_ appear to have the same physical meaning, although the comments note that attenuation is more commonly used for radar and extinction is more commonly used for visible light. The number of std_names using each of them is 2 and 1, respectively, so it should be easy to fix with aliases.
> 2) _backscattering_ and _backwards_scattering_ also appear to have the same definition. The number of std_names using each of them is 1 and 4, respectively, so it should be easy to fix with aliases. Although it is less common, I prefer _backscattering_ because it is a single word, and will generalize better to _forwardscattering_.

These are good points and I tend to agree with you. I am not an expert and
if there is a distinction someone will point it out, I hope. If there is no
distinction, the reason for the different choices would be because of what
is generally said, or from personal preference, I presume. It's a difficult
balance between making standard names use familiar terms, or making them use
consistent terms, but I would prefer consistency if it is still obviously
comprehensible to an expert.

Regarding the Mie scattering proposal, again I am not an expert on the science,
but I would comment that X_assuming_Y is generally used to indicate what X
would be in some hypothetical situation of assuming_Y e.g.
  surface_albedo_assuming_no_snow
which is not, in general, the same as surface_albedo as it truly is (although
it is often the same). It does not indicate a method of calculating X and,
as you say, we keep that out of standard names, because in principle a method
of measurement should not affect the definition of the quantity being measured.

Best wishes

Jonathan
Received on Mon Mar 12 2012 - 07:14:22 GMT