BackForwardInstrument:  VISSR (Himawari-5) 

Instrument details
Acronym VISSR (Himawari-5)
Full name Visible-Infrared Spin Scan Radiometer
Purpose Multi-purpose VIS/IR imagery
Short description
  • 4-channel VIS/IR radiometer [see detailed characteristics below]
  • Information on monitoring and calibration here
Background

Evolution of VISSR flown on Himawari 1 to 4
Scanning Technique

W-E continuous scanning (100 rps) by the spinning satellite rotation, N-S by mechanical stepping
Resolution 1.25 km at s.s.p. (VIS channel), 5 km at s.s.p. (IR channels)
Coverage / Cycle Full disk each 30 min
Mass Power Data Rate

 

Providing Agency JAXA
Instrument Maturity Flown on operational programme
Utilization Period: 1995 to 2003
Last update: 2024-09-30
Detailed characteristics

Central wavelength

Spectral interval

SNR or NEΔT @ specified input

0.72 µm

0.55-0.90 µm

6.5 @ 2.5 % albedo or 43 @ 95 % albedo

6.75 µm

6.5-7.0 µm

1.0 K @ 300 K

11.0 µm

10.5-11.5 µm

0.5-0.65 K @ 300 K

12.0 µm

11.5-12.5 µm

0.5-0.65 K @ 300 K
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
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*2 - very 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.1VIS and TIR channels
Fire radiative power5 - marginalCloud sensitive.. Coarse spatial resolution.1TIR channels. Frequent sampling (GEO) enables early detection
Fire temperature5 - marginalCloud sensitive.. Coarse spatial resolution.1TIR channels. Frequent sampling (GEO) enables early detection
Land surface temperature4 - fairCloud sensitive.TIR split window channels around 11 micrometers for water vapour correction
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 temperature4 - fairCloud sensitive.TIR split window channels around 11 micrometers for water vapour correction
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)*2 - very highCloud sensitive.TIR channels around 6.3 micrometers and in the 11 micrometers split window
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