Ron,
A key conclusion of GALEON Phase 1 is that GML is irrelevant and should be
abandoned as soon as possible..... JUST KIDDING, JUST KIDDING!!!
Seriously though -- and others should chime in with additions or modifications
to the following comments which reflect my views on the three main areas where
GALEON is now and will be (in Phase 2) involved with GML.
The earliest development in this area and perhaps furthest along is the
ncML-GML work being spearheaded at the University of Florence CNR/IMAA. It is
based on the earlier development of the ncML (netCDF Markup Language). My
personal way of characterizing ncML-GML is that it combines the disciplinary
semantics (what do the numbers in the dataset represent?) of ncML with the
spatio-temporal (the where and when of the numbers in the dataset) semantics in
GML.
A complementary approach being developed by the UK BADC/NERC group is the
(Climate Science Modelling Language). Here again I'll offer my oversimplified
characterization of the main difference between CSML and ncML-GML, namely, that
the the disciplinary semantics and spatio-temporal semantics are more tightly
coupled in CSML whereas they are loosely coupled in ncML-GML.
The two initiatives above have been underway for some time now, but are not at
a point where we could submit them as finished products of GALEON Phase 1. The
development and coordination of the two efforts will be one of the most
important facets of GALEON Phase 2. While it's a bit out of date, I put
together a brief description of various means (both implicit and explicit) of
representing netCDF semantics (including ncML-GML and CSML) along with a very
simple set of examples at:
http://www.unidata.ucar.edu/projects/THREDDS/GALEON/NetCDFandStandards.htm
for what it's worth.
A third key area for GALEON related to GML is in the very initial stages. This
involves determining the relationships (if any) among various types of GALEON
netCDF datasets (especially the sort of 5D datasets output from numerical
weather and climate forecast models), ncML-GML, CSML, and GMLJ2 (GML JPEG2000).
We had a few preliminary discussions at the Bonn TC meeting on this
GALEON/GMLJP2 topic and my opinion is that we learned enough to become
convinced that the topic area needs much more study. Unfortunately I don't
think all the knowledgable players will be at the Huntsville meetings, but we
will target this as a goal for GALEON Phase 2.
I hope others will correct anything I've misrepresented or add some of the
important aspects I may have left out.
-- Ben
On 2/24/06, Ron Lake <rlake@xxxxxxxxxxxxx> wrote:
What is the current role of GML in GALEON?
Cheers
Ron
