[CF-metadata] standard names for variables?in?'raw?engineering' units

[John Graybeal]

Thank you all for all your thoughts on this.

Jonathan Gregory <j.m.gregory at reading.ac.uk> 03/12/09 9:57 PM >>>

> I don't really know what it is, of course, but it sounds like it  
> could have a standard name of ctd_fluorometer_voltage and units of  
> V. <snip> Here, the quantity being named relates specifically to a  
> means of measurement, not to the final product.


I must quibble. The quantity being named relates specifically to the  
_units_ of the measurement, not the means of measurement. And the  
reason this (new standard name) must be done is that Standard Names  
are specifically tied to units (via the canonical units requirement),  
and so the strange unit forces a different standard name.

And so for purest reflection of meaning, we are back to something like  
'variant_unit' (instead of 'raw').  I discourage incorporating the  
unit in the standard name ('voltage' in Jonathan's example) because  
there is no way to know if *this* temperature_voltage variable is  
interoperable with *that* temperature_voltage, unless attributes for  
conversion to canonical units are provided.  So the units attribute  
can name the units, and this standard name should just make clear that  
the units are not canonical units.

And, can we make it an item in appendix C, please?

> What are example of non-udunits? V is a udunit, all right. Perhaps a  
> non-udunit
> is just a count of something? Does that need units? It could simply be
> regarded as dimensionless.


Addressed in other thread; no non-udunits have been identified so far  
relating to raw geophysical data.

John

--------------
John Graybeal   <mailto:graybeal at mbari.org>  -- 831-775-1956
Monterey Bay Aquarium Research Institute
Marine Metadata Interoperability Project: http://marinemetadata.org