Hi Ben (et al),
We're continuing our work on CSML within the UK NERC DataGrid project,
and have extended our GALEON Phase 1 WCS prototype to operate with a
'CSML Provider' at the backend (as mentioned in Edinburgh
http://glue.badc.rl.ac.uk/cgi-bin/TPAC/WCS). We're currently finalising
a new version of CSML.
Also of interest is some work by our colleagues at Reading on the DEWS
project who are developing multidimensional extensions to geoserver to
be able to handle 4-d gridded data and netCDF
(http://docs.codehaus.org/display/GEOS/Multidimensional+WCS).
Best regards,
- Andrew
-----Original Message-----
From: owner-galeon@xxxxxxxxxxxxxxxx
[mailto:owner-galeon@xxxxxxxxxxxxxxxx] On Behalf Of Ben Domenico
Sent: 05 August 2006 00:31
To: Unidata GALEON
Cc: Kenneth R. McDonald; Nadine Alameh; Beth A Plale; Tom
Baltzer; Olga Wilhelmi; Jennifer Boehnert; Scott Shipley
Subject: GALEON IE Phase 2 Objectives
Hi,
During the last several weeks at the Unidata User Workshop,
the ESIP Federabion meeting, and at IGARSS 2006, I had the
opportunity to discuss possible objectives for the GALEON
Phase 2 Interoperability Experiment with a number of GALEON
paricipants. From what I can decipher from my cryptic notes,
the goals can be divided into 3 categories:
1. Implement and test clients and servers that conform to the
new WCS 1.1 spec and experiment with them on a wide range of
real-world datasets. From the GALEON perspective, some of
the important changes in WCS 1.1 are:
-- multiple coverages in one request
-- multiple fields in a coverage
-- 3 spatial dimensions
-- 2 time dimensions (e.g., the time a forecast was run and
the forecast times within the run)
-- relative time ( e.g., the latest image, the last 5 images, ...)
-- non-spatial dimension (e.g., pressure or density)
-- irregular grids
2. Catalogs and/or WCS getCapabilities lists? The
getCapabilities request appears to be inadequate to return a
list of all the coverages on a WCS server. Several people
have suggested that GALEON Phase 2 include experiments that
involve CS-W (Catalog Services for the Web) as well as WCS.
As an illustration of the challenge, the top level THREDDS
catalog represented in HTML at:
http://motherlode.ucar.edu:8080/thredds/catalog.html
includes several catalogs of catalogs of different types of
real time datasets. If you drill down in the "NCEP Model
Data," you'll get to collections of many datasets, each of
which contains hundreds of coverages. These catalogs are
being updated in near real time as new data arrive.
Currently these datasets are catalogued using THREDDS
technology, but it would be good to have a standards-based
interface as well. Without such catalogs, the WCS interface
is much less effective.
I should add that those NCEP model output datasets also
exhibit all the characteristics suggested for
interoperability testing in item 1 above so they can be used
as grist for a couple major phase 2 objectives.
3. GML dialects
There appears to be an accelerating trend to develop new XML
schemas for many subdisciplines in the geosciences. Even
within the world of GML, many profiles are evolving. Within
the GALEON team discussions, at least 3 have come up in the
context of methods for characterizing CF-netCDF
characteristics in a standard form:
-- ncML-GML
-- CSML
-- GMLJP2
Some effort toward testing the applicability and
effectiveness of these approaches would be valuable.
This is a pretty full agenda, but I would not expect all the
participants to work on all the items. On the other hand, it
would be usefull to have at least some effort focuse in each area.
There have also been some suggestions relating to web
processing and chaining services, but the general sense seems
to be to leave that to the OGCnetworks -- GALEON and GSN and
to collaborate with the ESIP Federation endeavors in that
realm. See:
http://wiki.esipfed.org/index.php/Web_Services
I am going to send a copy of this to a few colleagues who
expressed an interest in the work but are not part of the
GALEON team ... yet.
Please let us all know which (if any) aspects of the imposing
list of objectives your group would likely participate in.
Comments or corrections to any of this are welcome.
-- Ben
