Dear Jonathan,
On Mon, 2008-08-11 at 11:26 +0100, Jonathan Gregory wrote:
> Dear Ian
>
> > So, apart from T14, I think we're agreed.
>
> Splendid. On T14, I'll agree with you that it is helpful to indicate what sort
> of depth it is. The fact that it is the depth of an isotherm is a main point of
> the definition of the quantity, whereas temperature on sigma levels and
> temperature on pressure levels are really the same quantity, just like
> temperature on a lat-lon grid and temperature on a tripolar grid are the
> same quantity.
>
Yes - that's what I was trying to get at.
> However I'd like to suggest an alternative to ocean_isotherm_depth. What do
> you think of depth_of_isosurface_of_sea_water_temperature? This is of course
> not the common term but my aim is not to be obscure. I am thinking of
> (a) precision; "isotherm" might mean potential or in-situ temperature, I guess.
> (b) generality. Any quantity that is defined as a function of z might be
> inverted in this way. While "isotherm" is a fairly familiar word, we don't
> want to have to depend on the existence of a Greek-based "iso" word in order
> to name a quantity. Does "isosurface" have an obvious meaning to you?
The meaning is clear, even though I hadn't seen it before. I think
"contour level" and "isopleth" (which might be more familiar to
meteorologists) probably have 1D connotations (wikipedia defines lots of
isos as "a line through ..."). I think your suggestion is admirably
clear.
> It turns
> out to be a word that is in common use with this meaning e.g. IDL and ncar
> graphics both use the term, and it's in wikipedia.
>
> If this is too user-unfriendly I'll settle for ocean_isotherm_depth and if we
> have later problems we can sort it out with aliases.
>
No, that's fine - except that in NEMO it's defined in terms of theta,
not in-situ temp, so we want
T14 depth_of_isosurface_of_sea_water_potential_temperature (m)
(This sets an obvious precedent if someone wants to propose a standard
name based on in-situ T later.)
Is that OK?
Thanks,
Ian.
> Cheers
>
> Jonathan
--
Ian Culverwell B-2-81 Ocean and Sea Ice Modelling
Met Office FitzRoy Road Exeter Devon EX1 3PB United Kingdom
Tel: +44 (0)1392 884017 Fax: +44 (0)1392 885861
E-mail: ian.culverwell at metoffice.gov.uk http://www.metoffice.gov.uk
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Received on Mon Aug 11 2008 - 04:50:48 BST
