[CF-metadata] The use of CF cell constructs for point data

From: Jonathan Gregory <j.m.gregory>
Date: Wed, 11 Apr 2012 13:48:33 +0100

Dear Randy

> Why have you not used a "cell_measure" attribute in the event_energy data variable to associate this data variable with the event_area data variable as shown in example 7.3 in the CF standard (e.g. :cell_measures = "area: event_area" ?

I wondered about doing that too. I didn't do it because it seemed to me that
the area of the event was really a measured quantity i.e. a data variable,
rather than being a property of the space of measurement. But it could be done
as you describe. Would you describe the lightning area as a "cell_area"? If
not, I think it is probably not a cell_measure.

> (2)
> Should the CF convention standard be updated to state that a featureType of "point" can make use of cell constructs ? Currently chapter 7 starts "When gridded data does not represent ?..".

Perhaps we should drop the word "gridded"! It is not really clear what it
means, I would say. You describe your dataset as not gridded, because it is
not a structured grid, but it's still got cells, so cell_methods could apply.
cell_measures could definitely apply too, even if the cells are not in a
structured grid. They may still need to be averaged, integrated, etc., for
which the metrics are useful.

Best wishes

Jonathan
Received on Wed Apr 11 2012 - 06:48:33 BST