NetCDF

summary

The Network Common Data Form (netCDF) is a long-lived set of file formats and associated APIs designed by UCAR for multi-dimensional datasets. (Though its name resembles that of CDF, and their original designs were similar, the two products have greatly diverged.) The various versions are widely used in environmental science, especially atmospheric and oceanographic research. Currently it has two main versions, netCDF-3 and netCDF-4, which are quite different in implementation, and moderately different in API. There are also "subversions" of netCDF-3, notably "netCDF Classic." Tool support for netCDF-3 continues to exceed that for netCDF-4; but the latter, based on HDF5, is generally considered technically superior, so its tool support is increasing rapidly.

Notable features of netCDF include

• incorporation of metadata. netCDF is said to be "self-describing," in that the file format provides for a header describing the structure of the data. In practice, the utility of its metadata depends on the extent to which the data author provides and maintains it.
• platform independence via API: provided the user manipulates netCDF files via supported APIs (which are numerous), the user can effectively ignore issues such as endianness.
• backward compatibility. Software and API capable of manipulating netCDF-4 is also capable of manipulating netCDF-3, though of course advanced features of the later version are not accessible to files written for the earlier version.