Delivering Earth's Shapes & Colors in Near-Real Time: NPOESS Products and Their Characteristics for Users

The NPOESS Interface Data Processing Segment will produce an unprecedented variety and quantity of environmental data products. These must be delivered rapidly, responsively, and flexibly to its operational users. These products must also be delivered to a long term archives to be retained indefinitely, and distributed as needed to researchers and the public. An analogous delivery service will be designed into NPOESS software provided for users' direct broadcast satellite terminals. The data must be provided in a standardized format, and annotated with substantial metadata, to assure that the data can be understood by user applications immediately and in the distant future. To meet these requirements, the NPOESS program has selected the Hierarchical Data Format (ver. 5) from the National Center for Supercomputing Applications. HDF5 incorporates features that accommodate large and complex data structures, and features to imbed semantic and syntactic metadata. IDPS will provide content metadata consistent with National Spatial Data Infrastructure standards. The program is working with Raytheon, the IDPS contractor, to develop simple but complete profiles to be used to guide data product and metadata design. The profile will balance ease of use, which influences ingest processing complexity and delay; and data set size, which influences storage and communications cost, and access and transmission delays.