BackForwardInstrument:  MRIR 

Instrument details
Acronym MRIR
Full name Medium Resolution Infrared Radiometer
Purpose To observe integrated short-wave and long-wave radiation from Earth to Space and its main components (water vapour, window, CO2).
Short description 5-channel radiometer, two broad-band (0.2-4.0 μm and 5-30 μm), three narrow-band (6.4-6.9 μm, 10-11 μm and 14-16 μm). On Nimbus-3 the 5-30 μm channel was replaced by 20-23 μm
Background First Earth radiation budget instrument
Scanning Technique Cross-track, swath 3000 km
Resolution 55 km at s.s.p.
Coverage / Cycle Global each day
Mass Power Data Rate


Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1961 to 1972
Last update: 2014-09-24
Detailed characteristics
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
  • Broadband Earth radiation radiometer
WIGOS Subcomponents
  • Subcomponent 1
  • Absolutely calibrated broadband radiometers, and TSI and SSI radiometers
  • Broadband radiometer (for ERB)
Mission objectives
Primary mission objectives
  • Upward long-wave irradiance at TOA
  • Upward short-wave irradiance at TOA
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
Upward short-wave irradiance at TOA*2 - very highInformation on BRDF needed.SW and LW broadband channels, and supporting narrow-bandwidth channels for cloud detection
Upward long-wave irradiance at TOA*1 - primaryNo specific limitation.SW and LW broadband channels, and supporting narrow-bandwidth channels for cloud detection