Gap analyses by variable, type of mission or WIGOS subcomponent Help icon

Select gap analysis type

Select analysis type

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In "Simplified" mode, the results in the analysis are calculated by looking at each instrument's mission objectives: for each instrument we keep track of what the primary, secondary, and opportunity mission objectives are. These mission objectives indicate that an instrument is primarily envisioned to measure variable X, Y and Z, that variables A, B and C are its secondary objective, and that it may offer the opportunity to measure variables I and II although it is not optimized for that. The simplified Gap analysis produces a timeline based on this information. The simplified Gap analysis is only available for analyzing variables, not for missions.
In "Expert system" mode, the results in the analysis are calculated with an expert system. Internally, OSCAR works with a large set of 1700 rules that determine whether or not an instrument is capable of measuring a given variable, and to what degree. When you select "Expert system", the Gap analysis is performed based on this large set of rules.

Select a Variable

Select a type of Mission

Select a WIGOS subcomponent

Variable sorting criteria


Each instrument is assigned with a 5-step rating, evaluated as a blend of several elements such as the uncertainty, the vertical resolution, and the frequency and spatial resolution of the retrieved measurement in comparison with the space-time variability of the geophysical parameter.  For this particular Variable, the rating is driven by:

  • the spectral bands exploited to detect the various types of cloud;
  • the night and day observing capability.




  • Radiometer with channels in 5 bands: VIS + NIR + SWIR + MWIR + TIR


  • Radiometer with channels in 4 bands: VIS +  MWIR + TIR + (NIR or SWIR)
  • Radiometer with channels in 4 bands: VIS +  NIR + SWIR + TIR


  • Radiometer with channels in 3 bands: VIS + TIR + (SWIR or MWIR); or SWIR + MWIR + TIR
  • Spectrometer covering 3 bands: NIR + SWIR + TIR; or 2 bands: MWIR + TIR


  • Radiometer with channels in 2 bands: TIR + (VIS or MWIR)
  • Hyperspectral radiometer or spectrometer covering 3 bands: NIR + SWIR + (VIS or MWIR)
  • Hyperspectral radiometer or spectrometer covering 2 bands: NIR + SWIR


  • TIR or MWIR radiometer or spectrometer
  • Radiometer or spectrometer with channels in VIS or (VIS + NIR) or (VIS + NIR + SWIR)
  • Panchromatic imager
Measurement timeline for Cloud cover Help icon
Hint: Move around in the timeline by scrolling up, down, left or right.