BackForwardInstrument:  ERM-1 

Instrument details
Acronym ERM-1
Full name Earth Radiation Measurement - 1
Purpose Earth radiation budget
Short description Two channels.  Two units, one scanning, one non-scanning [see detailed characteristics below]
Background New development. Operations on FY-3A stopped in 2009. Operations on FY-3B stopped in 2011
Scanning Technique Scanner: swath 2300 km; cross-track scanning,151 steps of 28 km s.s.p. every 4 s; non-scanning: 120 degrees viewing angle (2200 km), 8 samples every 4 s.
Resolution Scanner:  28 km
Coverage / Cycle Global coverage twice/day (total radiance) or once/day (short-wave)
Mass 37 kg Power 40 W Data Rate 2.6 kbps


Providing Agency CMA
Instrument Maturity Flown on operational programme
Utilization Period: 2008 to 2021
Last update: 2021-06-02
Detailed characteristics
Channel Spectral interval Noise Equivalent Radiance Absolute accuracy SNR

Short-wave (outgoing)

0.2 - 3.8  µm 0.4  W m-2 sr-1 1.5  W m-2 sr-1 900

Total radiance (outgoing)

0.2 - 50  µm 0.4  W m-2 sr-1 1.1  W m-2 sr-1 1250
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 Total (SW+LW) broadband channels
Upward long-wave irradiance at TOA*2 - very highNo specific limitation.LW radiance achieved by difference between Total and SW