BackForwardInstrument:  VIIRS 

Instrument details
Acronym VIIRS
Full name Visible/Infrared Imager Radiometer Suite
Purpose Multi-purpose imagery, including ocean colour
Short description 22 channels, including a day/night 0.7 µm channel [see detailed characteristics below]
Background New development, developed in the NPOESS framework
Scanning Technique Cross-track: 16 parallel lines sampled by 2048 pixel of 750 m s.s.p. and 32 parallel lines sampled by 4096 pixel of 370 m s.s.p.; swath 3000 km.  Along-track: one 11.9-km strip of 16 or 32 lines in 1.786 s
Resolution 375 m for five AVHRR-like channels and the VIS day/night channel, 750 m for all other channels. See table
Coverage / Cycle Global coverage twice/day (IR and day/night VIS/NIR channel) or once/day (VIS)
Mass 275 kg Power 240 W Data Rate 5.9 Mbps

 

Providing Agency NASA
Instrument Maturity Flown on operational programme
Utilization Period: 2000 to ≥2038
Last update: 2016-10-15
Detailed characteristics

Central wavelength

Bandwidth

SNR or NEΔT @ specified input (High or single gain)

SNR or NEΔT @ specified input (Low gain)

Resolution

412 nm

20 nm

352 @ 45 W m-2 sr-1 µm-1

316 @ 155 W m-2 sr-1 µm-1

750 m

445 nm

18 nm

380 @ 40 W m-2 sr-1 µm-1

409 @ 146 W m-2 sr-1 µm-1

750 m

488 nm

20 nm

416 @ 32 W m-2 sr-1 µm-1

414 @ 123 W m-2 sr-1 µm-1

750 m

555 nm

20 nm

362 @ 21 W m-2 sr-1 µm-1

315 @ 90 W m-2 sr-1 µm-1

750 m

672 nm

20 nm

242 @ 10 W m-2 sr-1 µm-1

360 @ 68 W m-2 sr-1 µm-1

750 m

746 nm

15 nm

199 @ 9.6 W m-2 sr-1 µm-1

 

750 m

865 nm

39 nm

215 @ 6.4 W m-2 sr-1 µm-1

340 @ 33.4 W m-2 sr-1 µm-1

750 m

1240 nm

20 nm

101 @ 5.4 W m-2 sr-1 µm-1

 

750 m

1378 nm

15 nm

83 @ 6.0 W m-2 sr-1 µm-1

 

750 m

1610 nm

60 nm

342 @ 7.3 W m-2 sr-1 µm-1

 

750 m

2250 nm

50 nm

10 @ 0.12 W m-2 sr-1 µm-1

 

750 m

3.70 µm

0.18 µm

0.40 K @ 270 K

 

750 m

4.05 µm

0.155 µm

0.11 K @ 300 K

0.42 K @ 380 K

750 m

8.55 µm

0.30 µm

0.09 K @ 270 K

 

750 m

10.763 µm

1.00 µm

0.07 K @ 300 K

 

750 m

12.013 µm

0.95 µm

0.07 K @ 300 K

 

750 m

0.7 µm (day/night)

0.5-0.9 µm

6 @ 6.70 10-5 W m-2 sr-1 µm-1

 

375 m

0.64 µm

0.60-0.68 µm

119 @ 22 W m-2 sr-1 µm-1

 

375 m

0.865 µm

0.845-0.884 µm

150 @ 25 W m-2 sr-1 µm-1

 

375 m

1.61 µm

1.58-1.64 µm

6 @ 7.3 W m-2 sr-1 µm-1

 

375 m

3.74 µm

3.55-3.93 µm

2.50 K @ 270 K

 

375 m

11.45 µm

10.5-12.4 µm

1.50 K @ 210 K

 

375 m

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
Mission objectives
Primary mission objectives
  • Biomass
  • Cloud cover
  • Cloud optical depth
  • Cloud top height
  • Cloud top temperature
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Tentative 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
VariableRelevance for measuring this variableOperational limitationsExplanation
Aerosol column burden3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth), NIR and SWIR channels including 760 nm for high-level aerosol
Aerosol effective radius5 - marginalCloud sensitive.. Daylight only.VIS (with narrow bandwidth), NIR (including 760 nm for high-level aerosol), and SWIR channels
Aerosol mass mixing ratio4 - fairCloud sensitive.. Daylight only.VIS (with narrow bandwidth), NIR and SWIR channels including 760 nm for high-level aerosol
Aerosol Optical Depth3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth), NIR and SWIR channels including 760 nm for high-level aerosol
Aerosol type4 - fairCloud sensitive.. Daylight only.VIS (with narrow bandwidth), NIR and SWIR channels including 760 nm for high-level aerosol
Biomass4 - fairCloud sensitive.. Index only.. Daylight only.VIS, NIR and SWIR channels. Biomass inferred from NDVI and LAI
Cloud cover1 - primaryNo specific limitation.VIS, NIR, SWIR, MWIR and TIR channels
Cloud drop effective radius4 - fairAt cloud top.. Daylight only.VIS, NIR, SWIR and MWIR channels (for differentiation)
Cloud ice effective radius4 - fairAt cloud top.. Daylight only.VIS, NIR, SWIR and MWIR channels (for differentiation)
Cloud optical depth3 - highLow-density cloud only.. Daylight only.VIS, NIR and SWIR channels
Cloud top height3 - highNo specific limitation.TIR channels in window and water vapour band (for emissivity) to estimate cloud top height from its temperature
Cloud top temperature2 - very highNo specific limitation.TIR channels in window and water vapour band (for emissivity)
Cloud type1 - primaryNo specific limitation.VIS, NIR, SWIR, MWIR and TIR channels
Colour Dissolved Organic Matter (CDOM)4 - fairCloud sensitive.. Daylight only.A few narrow-bandwidth VIS channels, suitable for a few water types, mainly in open ocean
Downward short-wave irradiance at Earth surface4 - fairCloud sensitive.. Highly indirect.VIS, NIR and SWIR channels
Downward long-wave irradiance at Earth surface5 - marginalCloud sensitive.. Highly indirect.MWIR and TIR channels including water vapour and CO2 bands
Earth surface albedo4 - fairCloud sensitive.VIS channels
Fire fractional cover3 - highCloud sensitive.. Coarse spatial resolution.VIS, MWIR and TIR channels
Fire radiative power3 - highCloud sensitive.. Coarse spatial resolution.MWIR and TIR channels
Fire temperature3 - highCloud sensitive.. Coarse spatial resolution.MWIR and TIR channels
Fraction of Absorbed PAR (FAPAR)3 - highCloud sensitive.VIS channels including Red at 700 nm
Land surface temperature3 - highCloud sensitive.MWIR and TIR window channels (high sensitivity to high temperature, cloud impact reduction, water vapour correction)
Leaf Area Index (LAI)2 - very highCloud sensitive.. Daylight only.VIS, NIR and SWIR channels
Normalised Difference Vegetation Index (NDVI)2 - very highCloud sensitive.VIS and NIR channels
Ocean chlorophyll concentration 4 - fairCloud sensitive.. Daylight only.A few narrow-bandwidth VIS channels, suitable for a few water types, mainly in open ocean
Ocean Diffuse Attenuation Coefficient (DAC)4 - fairCloud sensitive.. Daylight only.A few narrow-bandwidth VIS channels, suitable for a few water types, mainly in open ocean
Ocean suspended sediments concentration4 - fairCloud sensitive.. Daylight only.A few narrow-bandwidth VIS channels, suitable for a few water types, mainly in open ocean
Oil spill cover4 - fairCloud sensitive.. Daylight only.VIS channels with narrow bandwidth
Photosynthetically Active Radiation (PAR)4 - fairCloud sensitive.VIS channels, range undersampled
Sea surface temperature2 - very highCloud sensitive.MWIR and TIR window channels around 3.7 and 11 micrometers (cloud impact reduction, water vapour correction)
Sea-ice cover1 - primaryCloud sensitive.VIS, NIR (for contour enhancement), SWIR (for discrimination from clouds), MWIR and TIR channels
Short-wave cloud reflectance4 - fairNo specific limitation.VIS and NIR channels
Snow cover3 - highCloud sensitive.. Daylight only.VIS, NIR and SWIR channels, enabling screening snow from clouds
Soil moisture at surface4 - fairCloud sensitive.. Index only.VIS, NIR, SWIR, MWIR and TIR channels. Soil moisture inferred from differential brightness and thermal inertia
Integrated Water Vapour (IWV)2 - very highCloud sensitive.TIR channels around 6.3 micrometers and in the 11 micrometers split window
Upward short-wave irradiance at TOA4 - fairSpectral interpolation needed.. Information on BRDF needed.VIS, NIR and SWIR channels
Upward long-wave irradiance at TOA4 - fairSpectral interpolation needed.MWIR and TIR channels in windows around 3.7 and 11 micrometers, and in water vapour and CO2 bands around 4.3 and 6.3 micrometers
Upward long-wave irradiance at Earth surface5 - marginalCloud sensitive.. Highly indirect.MWIR and TIR channels in windows around 3.7 and 11 micrometers, and in the water vapour band around 6.3 micrometers
Aerosol volcanic ash4 - fairCloud sensitive.. Daylight only.VIS, NIR and SWIR channels including 760 nm for high-level ashes
Aerosol volcanic ash (Total column)3 - highCloud sensitive.. Daylight only.VIS, NIR and SWIR channels including 760 nm for high-level ashes
Wind (horizontal)4 - fairCloud or water vapour tracers needed.. Polar regions only.TIR channels in the 11 micrometers window and the 6.3 micrometers water vapour band