BackForwardInstrument:  S-VISSR (FY-2A/B) 

Instrument details
Acronym S-VISSR (FY-2A/B)
Full name Stretched Visible and Infrared Spin Scan Radiometer
Purpose Multi-purpose imagery and wind derivation by tracking clouds and water vapour features
Short description
  • 3 VIS/TIR channels [see detailed characteristics below]
  • Calibration monitoring here
Background

Similar to the Meteosat MVIRI
Scanning Technique

Mechanical, spinning satellite, E-W continuous, S-N stepping
Resolution 5.76 km for IR channels; 1.44 km for the VIS channel
Coverage / Cycle Full disk every 30 min.  Limited areas in correspondingly shorter time intervals
Mass 82 kg Power 75 W Data Rate 14 Mbps

 

Providing Agency CMA
Instrument Maturity Flown on operational programme
Utilization Period: 1997 to 2004
Last update: 2024-09-09
Detailed characteristics

Spectral interval

SNR or NEΔT @ specified input

0.55 - 1.05 µm

43 @ 95 % albedo

6.30 - 7.60 µm

1.0 K @ 300 K

10.5 - 12.5 µm

0.5 K@ 300K
Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Earth observation instrument
  • Passive optical radiometer or spectrometer
  • Moderate resolution optical imager
WIGOS Subcomponents
  • Subcomponent 1
  • Multi-spectral VIS/IR imagery With rapid repeat cycles [in GEO]
  • Multi-spectral VIS/IR imager with rapid repeat cycles [in GEO]
Mission objectives
Primary mission objectives
  • Cloud cover
  • Cloud top height
  • Cloud top temperature
  • Cloud type
  • Integrated Water Vapour (IWV)
  • Wind (horizontal)
Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Accumulated precipitation4 - fairConvective precipitation dominant.. Calibration by MW needed.TIR channel(s) in the 10-13 micrometers range. Frequent sampling (GEO) is essential for accumulated precipitation.
Cloud cover*4 - fairNo specific limitation.VIS and TIR channels
Cloud top height*3 - highNo specific limitation.TIR channels in window and water vapour band (for emissivity) to estimate cloud top height from its temperature
Cloud top temperature*3 - highNo specific limitation.TIR channels in window and water vapour band (for emissivity)
Cloud type*4 - fairDaylight only.VIS and TIR channels
Fire fractional cover4 - fairCloud sensitive.. Coarse spatial resolution.VIS and TIR channels
Fire radiative power5 - marginalCloud sensitive.. Coarse spatial resolution.TIR channels. Frequent sampling (GEO) enables early detection
Fire temperature5 - marginalCloud sensitive.. Coarse spatial resolution.TIR channels. Frequent sampling (GEO) enables early detection
Precipitation intensity at surface (liquid or solid)3 - highConvective precipitation dominant.. Calibration by MW needed.TIR channel(s) in the 11 micrometers window. Frequent sampling (GEO) consistent with precipitation temporal variability
Sea surface temperature5 - marginalCloud sensitive.TIR window channel(s) around 11 micrometers .
Snow cover5 - marginalCloud sensitive.. Daylight only.VIS channel(s). Frequent sampling (GEO) improves probability of cloud-free views
Soil moisture at surface4 - fairCloud sensitive.. Index only.VIS and TIR window channels. Soil moisture inferred from thermal inertia, that is accurately measured by frequent sampling (GEO)
Integrated Water Vapour (IWV)*4 - fairCloud sensitive.. Middle troposphere dominant.TIR channels in the water vapour band around 6.3 micrometers
Aerosol volcanic ash Total Column1 - primaryCloud sensitive.TIR channel(s). Frequent sampling (GEO) enables early detection of ash plumes
Wind (horizontal)*3 - highCloud or water vapour tracers needed.VIS channel(s) and TIR channels around 6.3 and 11 micrometers. Frequent sampling (GEO) enables inference from cloud or water vapour pathces motion