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The Open Geospatial Consortium membership is seeking comments on an OGC candidate standard, the Network Common Data Form (netCDF) Enhanced Data Model Extension Encoding Standard.
The OGC has previously approved two netCDF standards: the OGC netCDF Core Encoding Standard, and netCDF Binary Encoding Extension Standard - netCDF Classic and 64-bit Offset Format. The proposed extension standard for the netCDF enhanced data model (introduced with netCDF-4) allows complex data structures to be represented very easily, allowing for more efficient programming. In performance-critical applications, the enhanced model provides significant benefits. Moreover, if existing HDF5 (Hierarchical Data Format, release 5) applications that depend on groups, user-defined types, unsigned types, or strings produce or use these data, the netCDF enhanced data model is required.
The netCDF enhanced data model was introduced as part of netCDF-4 in 2008. The enhanced data model added support for per-variable compression, multiple unlimited dimensions, more complex data types, and better performance by layering an enhanced netCDF access interface on top of the HDF5 format. For more on the differences between the netCDF classic data model and the netCDF enhanced data model, see this diagram.
UCAR/Unidata and other OGC members originally introduced netCDF into the OGC as a candidate OGC standard to encourage broader international use and greater interoperability among clients and servers interchanging data in binary form. Among other benefits, this will make the large collections of environmental netCDF data more readily accessible and usable by non-experts. In addition to their ongoing development of netCDF itself, Unidata Program Center staff have been working with the OGC to provide the formal specifications necessary for netCDF's adoption as an OGC standard.
The candidate OGC Network Common Data Form (NetCDF) NetCDF Enhanced Data Model Extension Encoding Standard and information about submitting comments are available at http://www.opengeospatial.org/standards/requests/88. The public comment period closes on July 1, 2012.
The OGC is an international consortium of more than 445 companies, government agencies, research organizations, and universities participating in a consensus process to develop publicly available geospatial standards. OGC Standards support interoperable solutions that "geo-enable" the Web, wireless and location-based services, and mainstream IT. OGC Standards empower technology developers to make geospatial information and services accessible and useful with any application that needs to be geospatially enabled.