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Hi, This is just a quick summary of a few highlights from last week's OGC Technical Committee meetings -- on topics of interest to Unidata and the GALEON project. Relating to CF-netCDF, there was discussion of the new encoding format document for which a draft is nearly ready to be submitted as a WCS standard extension specification. There is still some concern that this encoding format specification will be closely coupled to the actual WCS protocol specification and a suggestion was made that coverage encoding format documents be submitted as "best practices" documents rather than standard extensions. However, subsequent discussions via email and at the meeting led to the conclusion that a "best practices" approach would lead to a coupling with the standard that was too loose. So the operative plan now is to continue on the previous path and submit the CF-netCDF encoding specification as a WCS standard extension as soon as possible. Other groups are working on similar specifications for JPEG2000 format and the related JPIP streaming delivery protocol. It was noted that the netCDF community may be interested in the JPIP spec as a model for how OPeNDAP could be introduced into the mix of WCS encoding specifications. There was also interest in the fact that we are attempting to map a variety of scientific data types (e.g., the Unidata CDM scientific data types, the BADC Climate Science Modelling Language scientific feature types) as coverages as understood by ISO. This would include collections of point, station, sounding, trajectory, radar scan, swath, etc. that are not "gridded" and hence have not traditionally been thought of as coverages. The ISO 19123 coverage definition does however include collections of discrete point. For the netCDF community, the first order of business is to extend and adapt the CF conventions to encompass these data types fully. In terms of catalogs, there were discussions with the ESRI reps who indicated that there may actually be some facilities for tying CSW catalog information with WCS access in the new arcGIS 9.3. But none of the people at the meeting has really had enough experience with these OGC interfaces in that release to say exactly how that can be done. It's something I have to follow up on. It was confirmed that the 9.3 WCS client cannot access CF-netCDF encoded information. So our initial experiments with the beta release are in fact accessing geoTIFFs from THREDDS Data Servers. In discussing it, we concluded that this is not as much of a mystery as it seemed initially. The native netCDF read/write (from local disk) capability in arcGIS 9.2 actually only brings in 2D "slices" at a time, but that restriction is not possible in the current WCS implementations. Lorenzo Bigagli gave an excellent summary of the ESSI (Earth and Space Science Informatics) sessions at the recent EGU conference. He also indicated that a new release of the Gi-GO catalog and data access client is in the works. The discussions of Google's KML were focused mainly on mass market display of data in Google Earth and Google Maps. Much of the interaction was dominated by commercial applications interested in wide exposure to large segments of the general public. The emphasis is on the display of data and not so much on the analysis tools needed by the research community. Obviously there is considerable interest in the academic community, but, in terms of supporting infrastructure, what might be of most use is some sort of service that would automate the process of conversion of netCDF data slices into KML for display. The meeting presentations are available at: http://portal.opengeospatial.org/index.php?m=projects&a=view&project_id=82&tab=2&artifact_id=27720 -- Ben
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