Dear Mark, and all,
Going through this very interesting thread once more, I wonder if one solution to make the definitions evolve could be to introduce a new grammar to form the standard names of vector components by using a mechanism ? la standard name modifiers.
You might know I started on a trac ticket (
https://cf-pcmdi.llnl.gov/trac/ticket/79) who aimed at uniting vector components into a single object. I have been away from work for the last few months and could not conclude on this, but I certainly hope to be able to revive this soon.
Part of my proposal relied on introducing new standard names for vector quantities, e.g. wind_vector, sea_ice_velocity_vector, sea_surface_current_vector, etc...
A natural (at least in my mind) follow-up to this could be to revise the definition of standard names for the components by using standard name modifiers.
One could for example build "wind_vector northward_component", or "sea_ice_velocity_vector magnitude" or "sea_surface_current_vector direction". As far as the _x_ components are concerned, we could think of something like "wind_vector <name_of_the_projection_dataset>_x_component".
That would allow to 1) define the meaning of the components for all types vectors at once, and 2) maybe even to define the set of transformations from one pair of components to another, 3) re-unify the syntax for vector components which is currently not the same for winds, currents, sea ice quantities, etc...
I do not claim it solves the issue you originally raised (_x_ components being ill defined in some cases). But it could be seen as a way to introduce a new, thoroughly debated grammar for these standard names, and slowly alias or deprecate the ones currently in use.
Hope this helps (or at least not complicates things too much),
Thomas
Received on Tue May 15 2012 - 04:49:45 BST