Net CDF - NetCDF-Java Common Data Model

NetCDF-Java Common Data Model

The NetCDF-Java library currently reads the following file formats and remote access protocols:

  • BUFR Format Documentation (ongoing development)
  • CINRAD level II (Chinese Radar format)
  • DMSP (Defense Meteorological Satellite Program)
  • DORADE radar file format
  • GINI (GOES Ingest and NOAAPORT Interface) image format
  • GEMPAK gridded data
  • GRIB version 1 and version 2 (ongoing work on tables)
  • GTOPO 30-sec elevation dataset (USGS)
  • Hierarchical Data Format (HDF4, HDF-EOS, HDF5, HDF5-EOS)
  • NetCDF (classic and large format)
  • NetCDF-4 (built on HDF5)
  • NEXRAD Radar level 2 and level 3.

There are a number of other formats in development. Since each of these is accessed transparently through the NetCDF API, the NetCDF-Java library is said to implement a Common Data Model for scientific datasets.

The Common Data Model has three layers, which build on top of each other to add successively richer semantics:

  1. The data access layer, also known as the syntactic layer, handles data reading.
  2. The coordinate system layer identifies the coordinates of the data arrays. Coordinates are a completely general concept for scientific data; specialized georeferencing coordinate systems, important to the Earth Science community, are specially annotated.
  3. The scientific data type layer identifies specific types of data, such as grids, images, and point data, and adds specialized methods for each kind of data.

The data model of the data access layer is a generalization of the NetCDF-3 data model, and substantially the same as the NetCDF-4 data model. The coordinate system layer implements and extends the concepts in the Climate and Forecast Metadata Conventions. The scientific data type layer allows data to be manipulated in coordinate space, analogous to the Open Geospatial Consortium specifications. The identification of coordinate systems and data typing is ongoing, but users can plug in their own classes at runtime for specialized processing.

Read more about this topic:  Net CDF

Famous quotes containing the words common, data and/or model:

    “What the study of history and artistic creation have in common is a mode of forming images.”
    —Johan Huizinga (1872–1945)

    “This city is neither a jungle nor the moon.... In long shot: a cosmic smudge, a conglomerate of bleeding energies. Close up, it is a fairly legible printed circuit, a transistorized labyrinth of beastly tracks, a data bank for asthmatic voice-prints.”
    —Susan Sontag (b. 1933)

    “The best way to teach a child restraint and generosity is to be a model of those qualities yourself. If your child sees that you want a particular item but refrain from buying it, either because it isn’t practical or because you can’t afford it, he will begin to understand restraint. Likewise, if you donate books or clothing to charity, take him with you to distribute the items to teach him about generosity.”
    —Lawrence Balter (20th century)