Name                    Last modified       Size  Description

 Parent Directory        02-Jul-2008 03:27      -  
 COARDS/                 23-Dec-2004 03:25      -  
 GDT                     09-Jun-1998 00:00     1k  
 ICSPAT/                 23-Dec-2004 03:25      -  
 NCAR-RAF                11-Jan-2007 22:46     1k  
 NUWG/                   23-Dec-2004 03:25      -  
 PMEL-EPIC/              23-Dec-2004 03:25      -  

NetCDF Conventions

http://www.unidata.ucar.edu/software/netcdf/conventions.html

Unidata offers a repository and will maintain WWW links for sets of
netCDF conventions, as supported by the global `Conventions' attribute
described in the Attribute Conventions section of the netCDF User's
Guide. The following sets of conventions are currently available (some
are under development):

    * CF Conventions (Recommended, if applicable)
    * COARDS Conventions (1995 standard that CF Conventions extends and generalizes)
    * GDT Conventions (1999 standard that CF Conventions extends and generalizes)
    * CDC Conventions (for gridded data, compatible with but more restrictive than COARDS)
    * NCAR-RAF Conventions for Aircraft Data
    * AMBER Trajectory Conventions for molecular dynamics simulations
    * ARGO netCDF conventions for data centers
    * National Oceanographic Data Center NetCDF Conventions
    * NUWG Conventions (1992-1995 effort to create some observational data conventions)
    * PMEL-EPIC Conventions
    * Unidata Observation Dataset Conventions (Recommended)
    * Proposals for coordinate conventions and coordinate conventions postings (ongoing discussion)

If present in a netCDF file, `Conventions' is a global attribute that
is a character array for the name of the conventions followed by the
file. Originally, these conventions were named by a string that was
interpreted as a directory name relative to the directory
/pub/netcdf/Conventions/ on the host ftp.unidata.ucar.edu.

The web page

  http://www.unidata.ucar.edu/software/netcdf/conventions.html

is now the preferred and authoritative location for registering a URI
reference to a set of conventions maintained elsewhere. The FTP site
will be preserved for compatibility with existing references, but
authors of new conventions should submit a request to
support-netcdf@unidata.ucar.edu for listing on this page.

It may be convenient for defining institutions and groups to use a
hierarchical structure for general conventions and more specialized
conventions. For example, if a group named XXX agrees upon a set of
conventions for required attributes, attribute names, and netCDF
representations for certain discipline-specific data structures, they
may describing the agreed-upon conventions in a document associated
with the name "XXX", and files that followed these conventions would
contain the global attribute

    :Conventions = "XXX" ;

Later, if another group agrees upon some additional conventions for a
specific subset of XXX data, for example time series data, the
description of the additional conventions might be associated with the
name "XXX/Time_series", and files that adhered to these additional
conventions would use the global attribute

    :Conventions = "XXX/Time_series" ;

It is possible for a netCDF file to adhere to more than one set of
conventions, even when there is no inheritance relationship among the
conventions. In this case, the value of the `Conventions' attribute
may be a single text string containing a list of the convention names,
separated by blank space or commas, such as

    :Conventions = "XXX, YYY" ;

Typical conventions web sites will include references to documents in
some form agreed upon by the community that supports the conventions
and examples of netCDF file structures that follow the conventions.

Unidata will maintain this conventions web page and will also make
available disk space and web access for additional conventions
documents for communities lacking a server on which to publish their
own convention hierarchies.