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Real-time Ionospheric Scintillation Monitoring

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Updated at

Ionospheric Scintillation Index S4 (King's Park)

S4
Hong Kong Time

Number of Visible Satellites

No. of Satellites
Hong Kong Time
Scintillation Level:
Minor
Moderate
Strong
Points to note:
  1. The intensity of ionospheric scintillation is generally represented by the scintillation index S4 and can be classified into three levels: minor (S4<0.3), moderate (0.3≤S4<0.6) and strong (S4≥0.6). For further information, please visit the Observatory's Blog "Ionospheric Scintillation Monitoring".
  2. This webpage displays the ionospheric scintillation monitoring data recorded at the King's Park Meteorological Station over the past 12 hours. The data are displayed at 5-minute intervals and include the following:
    1. Upper graph: The maximum value of S4 indices calculated from all visible satellites of the selected satellite system(s) (BeiDou Navigation Satellite System (BDS) and/or Global Positioning System), at each timestamp.
    2. Lower graph: Number of visible satellites for the selected satellite system experiencing minor, moderate and strong signal scintillation respectively at each timestamp.
    Users may refer to the applicable information based on their needs. For instance, small unmanned aircraft (SUA) operators could check the satellite counts under minor signal scintillation level from the lower graph, as SUA shall successfully lock onto an adequate number of satellites during operations according to requirements of the Civil Aviation Department.
  3. Users can place the mouse cursor over the graphs to display the S4 value and the number of visible satellites with a certain signal scintillation level.
  4. This webpage updates every 5 minutes and displays data only from visible satellites at or above 30° elevation.
  5. The data displayed are provisional. Only limited data validation has been carried out.