JSON file description

The following variables are included in the JSON file:

• status : (green/orange/red) Green=nominal, Orange=no a priori information available by ionosondes, Red = data from less than 5 GNSS receiver stations available above 65 deg N OR less than 50 receives available in total.
• t_start : Start time of the epoch used for reconstruction (UTC).
• t_end : End time of the epoch used the reconstruction (UTC).
• ionosondes_N : Number of ionosondes in use. If zero the quality symbol is an orange square.
• ionosondes_as_measurements : Indicates if ionosondes are in use as direct measurements.
• GNSS_stations : Total number of GNSS receiver stations in use. If less than 50 the quality symbol is a red triangle.
• GNSS_stations_over_65 : Total numer GNSS receiver stations with latitude greater than 65 degrees. A good value is 5 or more stations. If less than 5 the quality symbol is a red triangle.
• GNSS_satellites : Three letter satellite identifiers, 'Gxx' GPS, 'Exx' Galileo, 'Rxx' Glonass, 'Cxx' BeiDou.
• GPS_measurements_N : Number of GPS measurements in use
• GLONASS_measurements_N : Number of Glonass measurements in use.
• GALILEO_measurements_N : Number of Galileo measurements in use.
• BEIDOU_measurements_N : Number of Beidou measurements in use.
• GNSS_measurement_averaging_window : Time window in use to average GNSS measurements in minutes.
• lat : Grid point latitudes (WGS84 decimal degrees)
• long : Grid point longitudes (WGS84 decimal degrees)
• alt : Grid point altitudes (kilometres)
• ne : Electron density (10^11 per cubic metre) at grid points.
• README : The same information that is given in this list.
• ACKNOWLEDGEMENT: Acknowledgements.