Just some off-the-cuff responses.
The GODAE project is worth looking into here -- they have adopted
OpenDAP and CF. I don't know how much activity the project has. There
seems to be a difference between USGODAE and the vanilla flavour. At any
rate, they don't seem to have published anything of significant for a
couple of years, but the project is a really nice idea.
Here in the Bureau, we have a moderate degree of standardisaton on
COARDS, but it's not an absolute rule.
The "easiest" way might be to support some particular convention in the
output, with the server being able to convert to that from a number of
different input conventions. For example, write code that will take
either a COARDS or CF input file, and do the relevant modifications to
the semantic-structure to present consistent output. That at least would
greatly simplify the task of visualisation (for example). If coupled
with a good generic data viewer (like IDV), then people would me even
more inclined to adopt the standard.
Here at the Bureau the biggest obstacle is the lack of a BUFR
interpreter for OpenDAP / thredds. This is a big deal for us, and we're
going to have to go with a hybrid solution instead of using OpenDAP
across the board. BUFR is an acronym for Binary Universal File
Representation, and has been adopted by the World Met Organisation as a
standard for obvervational data. It's a complete hassle to deal with,
because the level of software support is low.
The other thing I thought would be cool (while we're throwing ideas
around like popcorn) would be if Thredds was also a web service, with a
WSDL and so forth.
Do any such conventions exist for OpenDAP?
No. The idea is to let different disciplines impose whatever structure
they want on top of OPeNDAP. The more appropriate question would be
"Does the oceanographic (or the Earth Science) community have any such
convention?" Unfortunately, the answer is again no. That is my fault.
I should have recommended one a long time ago. I think that COARDS (or
CF) would be an excellent starting point and COARDS is becoming a de
facto standard in that many data providers use it. I was reluctant to
impose COARDS on the oceanographic use of the system since that would
mean the reordering of some archives which could be very costly. I
prefer a modified C
COARDS, one that does not adhere to the semantic structure, but does
adhere to the rest of the standard.
Here at BOM we more or less have our conventions agreed on for my
particular project, but if there were any recommended best practise
it could be interesting.
What do you think of adopting COARDS or CF? Would one or the other
address all of your data sets? If not, what is missing? If it could,
but your would rather not adopt it, it would really be useful to know
why and to know what you guys have adopted and why. I am hoping that
the Marine Metadata effort comes up with a recommendation for the
oceanographic community. I'm not sure what is being done for the
meteorological community, but it would be great if there was a similar
effort (to the Marine Metadata program) and if they came up with a
recommendation.
Peter
Cheers,
-Tennessee
--
Peter Cornillon
Graduate School of Oceanography - Telephone: (401) 874-6283
University of Rhode Island - Fax:
(401) 874-6728
Narragansett, RI 02882 - E-mail:
pcornillon@xxxxxxxxxxx
