Dear all,
I've not carefully followed all of the recent standard name discussion,
but I thought the idea was to identify the physical quantity, not how
it was measured or estimated (i.e., what instrument was used, what kind
of model was used, what approximations were assumed). If this is true,
it would be inappropriate (and lead to a huge number of standard names)
to include geostrophic velocity as a variant on velocity. If this
degree of specification is required, then wouldn't names like
"surface_temperature_from_an_energy_balance_climate_model" or
"surface_temperature_from_an_AOGCM" or "quasi-geostropic_velocity" also
become acceptable (which I would say is going too far).
I would like to draw the line on the side of fewer variants; hence,
recommend simply "surface_Xward_sea_water_velocity", with the details of
how it was calculated stored elsewhere in the metadata.
my 2 cents
Karl
Olivier Lauret wrote:
> Dear Jonathan and all
>
> I think what you suggested seems to be good, so I propose you some new
> satellite altimetry standard names.
> I don't think we'll need
> "surface_Xward_sea_water_geostrophic_velocity_assuming_reference_ellipsoid_for_geoid",
> so I haven't kept it.
>
> I also tried to give an explanation based on the definitions given in
> the standard name table; please let me know if something is not clear.
> So what do you think about:
>
> 1) sea_surface_height_above_reference_ellipsoid
> units: m
>
> 2) surface_eastward_sea_water_geostrophic_velocity, ms-1
> 3) surface_northward_sea_water_geostrophic_velocity, ms-1
>
> Explanation:
> The surface called "surface" means the lower boundary of the atmosphere.
> "Water" means water in all phases, including frozen i.e. ice and snow. A
> velocity is a vector quantity. "Eastward" indicates a vector component
> which is positive when directed eastward (negative westward).
> "Northward" indicates a vector component which is positive when directed
> northward (negative southward). "Geostrophic" indicates that geostrophic
> balance is assumed.
> surface_northward(eastward)_sea_water_geostrophic_velocity is the sum of
> a variable part
> [surface_northward(eastward)_sea_water_geostrophic_velocity_assuming_sea_level_for_geoid]
> and of a constant part due to the stationary component of ocean
> circulation.
>
>
> 4)
> surface_eastward_sea_water_geostrophic_velocity_assuming_sea_level_for_geoid,
> ms-1
> 5)
> surface_northward_sea_water_geostrophic_velocity_assuming_sea_level_for_geoid,
> ms-1
> Explanation:
> The surface called "surface" means the lower boundary of the atmosphere.
> "Water" means water in all phases, including frozen i.e. ice and snow. A
> velocity is a vector quantity. "Eastward" indicates a vector component
> which is positive when directed eastward (negative westward).
> "Northward" indicates a vector component which is positive when directed
> northward (negative southward)."Geostrophic" indicates that geostrophic
> balance is assumed. The geoid is a surface of constant geopotential.
> surface_eastward
> (northward)_sea_water_geostrophic_velocity_assuming_sea_level_for_geoid
> is the variable part of [surface_northward_sea_water_geostrophic_velocity].
> "sea_level" means mean sea level, and is assumed to be equal to the
> geoid so that the stationary component of ocean circulation is equal to
> zero.
>
> Waiting for your feedback,
>
> Regards
>
>
> Olivier Lauret
>
> CLS Space Oceanography Division
> Data Information and Diffusion
> 8-10 rue Hermes,
> 31526 Ramonville-St-Agne, Cedex, France
>
> Email: olivier.lauret at cls.fr
> Tel: (+33) (0) 561 39 48 51
> Fax:(+33) (0) 561 39 48 51
> Internet:
> http://www.cls.fr
> http://www.aviso.oceanobs.com/
>
>
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Received on Fri Aug 25 2006 - 10:03:36 BST
