Metadata recommendations for encoding netCDF products based on CF convention

This documentation provides some recommendations and examples for the encoding of structural metadata in a form suitable for archiving. The main encoding format it is the netCDF file format. These metadata recommendations are based on the CF-1.X Conventions, but some modifications and extensions are applied. The main objective of this recommendations is to provide input to the different data management plans for C3S projects (and others).

The use case for the example dataset been used in loadeR

The example dataset been used in loadeR needs to be refactorized following the next rules:

<?xml version='1.0' encoding='UTF-8'?>
<netcdf xmlns=''
    location='' >
  <dimension name='time' length='18262' />
  <dimension name='lat' length=    '6' />
  <dimension name='lon' length=    '9' />
  <dimension name='lev' length=    '4' />

  <!-- Updated the SMG URL -->
  <attribute name='history' value='Created by MeteoLab2netCDF on 04-Jun-2014 18:27:34' />
  <attribute name='institution' value='Santander Meteorology Group (UC-CSIC,' />
  <attribute name='info' value='Data generated for downscaleR toolbox (' />
  <!-- updated the CF convention version and URL-->
  <attribute name='Conventions' value='CF-1.6' />
  <attribute name='conventionsURL' value='' />
  <attribute name='creation_date' value='04-Jun-2014 19:07:33' />

  <variable name='time' type='double' shape='time' >
    <!-- Add the satndard_name attribute -->
    <attribute name='standard_name' value='time' />
    <!-- Improve long name attribute for Time or Valid Time -->
    <attribute name='long_name' value='time' />
    <attribute name='units' value='days since 1950-01-01 00:00:00' />
    <!-- Remove the Unidata Convention attributes. They are not required -->
    <!--attribute name='_CoordinateAxisType' value='Time' /-->
    <!-- Calendar attribute is required -->
    <attribute name='calendar' value='standard' />
  <variable name='lat' type='double' shape='lat' >
    <attribute name='standard_name' value='latitude' />
    <attribute name='long_name' value='latitude' />
    <attribute name='units' value='degrees_north' />
    <!-- Remove the Unidata Convention attributes. They are not required -->
    <!--attribute name='_CoordinateAxisType' value='Lat' /-->
  <variable name='lon' type='double' shape='lon' >
    <attribute name='standard_name' value='longitude' />
    <attribute name='long_name' value='longitude' />
    <attribute name='units' value='degrees_east' />
    <!--attribute name='_CoordinateAxisType' value='Lon' /-->
  <variable name='lev' type='double' shape='lev' >
    <!-- correct standard_name -->
    <attribute name='standard_name' value='air_pressure' />
    <!-- Improve long name attribute -->
    <attribute name='long_name' value='pressure level' />
    <attribute name='units' value='millibar' />
    <!-- Remove the Unidata Convention attributes. They are not required -->
    <!-- attribute name='_CoordinateAxisType' value='Z' /-->
    <attribute name='positive' value='down' />
  <variable name='Q' type='float' shape='time lev lon lat' >
    <attribute name='standard_name' value='specific_humidity' />
    <attribute name='long_name' value='Specific humidity' />
    <attribute name='units' value='kg kg**-1' />
    <!-- If missing data it's not expected, better it's not to use it -->
    <!-- attribute name='missing_value' value='-9999.0 ' type='float' /-->
    <!-- Coordinates are better to be explicit -->
    <attribute name='coordinates' value='time lev lon lat' />

Last modified 3 years ago Last modified on May 11, 2018 5:53:42 PM

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