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Checklist to create NetCDF grid data in the format of the Netcdf CF 1.6 conventions

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This checklist focusses on the points that are important to be able to import the netcdf data into Delft-FEWS. The full NetCDF CF-The full netcdf CF 1.6 conventions can be found on http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html^{Image Modified}This checklist focusses on the points that are important to be able to import the netcdf grid data into Delft-FEWS.

Note
TODO work in progress

Grid data

1. all data and coordinate variables should have a unique variable name and the following attributes:
   units (required)
   standard_name (required)
   long_name (recommended)
   _FillValue and/or missing_value (recommended)
   scale_factor (optional)
   add_offset (optional)
   Also see: http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html#units^{Image Modified} http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html#long-name^{Image Modified} http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html#standard-name^{Image Modified}
2. the standard_name attributes should comply to the list with standard names, see http://cfconventions.org/26.html
3. a data variable for a 2D grid must depend on three dimensions, representing time and two spatial dimensions (in the order time, y, x). The dimension names can be anything.
   For the time dimension there must be a corresponding time coordinate variable with the same name.
   If the grid is regular or rectangular, then for each spatial dimension there must be a corresponding coordinate variable with the same name. See http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html#idp5553648^{Image Modified}
   If the grid is rectangular or curvilinear, then the y and x coordinate variables are both two-dimensional and depend on both spatial dimensions. In this case the data variable must have an attribute "coordinates" that refers to the y and x coordinate variables (in that order), e.g. coordinates="y x"
   See http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html#idp5559280^{Image Modified}
4. if the data has a forecast reference time/analysis time/base time, then this time must be stored in a separate coordinate variable that contains only one value, which is the forecast reference time. This variable must have standard_name="forecast_reference_time". The name of this variable must be present in the coordinates attribute of the data variable, e.g. coordinates="analysis_time" or coordinates="y x analysis_time". If needed, different data variables can point to different forecast reference time variables. See http://cf-pcmdi.llnl.gov/documents/cf-conventionscfconventions.org/1.6/cf-conventions.html#scalar-coordinate-variables^{Image Modified}
5. the time coordinate variable must either have an attribute "units" with a valid unit of time and/or an attribute "axis" with value "T".
6. the time and spatial coordinate variables must have values either in ascending or in descending order.

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