BackForwardInstrument:  SCR (Nimbus-4) 

Instrument details
Acronym SCR (Nimbus-4)
Full name Selective Chopper Radiometer
Purpose Stratospheric temperature profile
Short description Correlation spectrometer exploiting pressurised CO2 cells, modulated so as to generate 6 channels in the 15 µm spectral band
Background New development
Scanning Technique Nadir only.
Resolution 160 km (for 2 higher absorption channels) or 112 km (for 4 lower absorption channels)
Coverage / Cycle Global in 10 days
Mass 15.3 kg Power 5 W Data Rate


Providing Agency UKSA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1970 to 1980
Last update: 2012-09-13
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
  • Cross-nadir infrared sounder, possibly including VIS channels
WIGOS Subcomponents No WIGOS subcomponents have been defined.
Mission objectives
Primary mission objectives
  • Atmospheric temperature
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
Atmospheric temperature*3 - highCloud sensitive.. Coarse vertical resolution.. Inaccurate in low troposphere.. Along-track only.Many TIR channels in the 15 micrometer band