Next round. After this I'll shut up for a while.
Standard Name Units
in_situ_density_of_seawater kg/m^3
potential_density_of_seawater kg/m^3
downwelling_photosynthetically_active_radiation microE/m^2/s
The first two would be commonly known as "sigma-t" and "sigma-theta". There's
currently an entry for "density", but it would kind of paper over the
difference between the two, and there is actually something of an issue with
their units. Typically, the actual value is between 1024 and 1028 kg/m^3 for
seawater, but historically 1000 is subtracted off of it to get a value
between 24 and 28. In fact, a lot of code assumes this. This would seem to
conflict with section 3.1 of the current beta standard, that
"The Udunits syntax that allows scale factors and offsets to be applied to a
unit is not supported by this standard. The application of any scale factors
or offsets to data should be indicated by the scale_factor and add_offset
attributes. Use of these attributes is discussed in detail in the section on
data packing which is their most important application. "
I assume that the first sentence means that "kg/m^3 _at_ -1000" is definitely not
allowed?
--
John Evans
johnevans at acm.org
Received on Mon Aug 04 2003 - 11:12:36 BST
