BackForwardInstrument:  SSM/T-2 

Instrument details
Acronym SSM/T-2
Full name Special Sensor Microwave - Humidity
Purpose Humidity sounding in nearly-all-weather conditions
Short description 5 channels MW radiometer covering the 183 GHz band [see detailed characteristics below]
Background New development
Scanning Technique Cross-track: 28 steps of 42 km ssp, swath 1500 km - Along-track: one 48-km line each 8 s
Resolution 48 km st s.s.p.
Coverage / Cycle Global coverage once/day
Mass 13.6 kg Power 26 W Data Rate 320 bps

 

Providing Agency DoD
Instrument Maturity Flown on operational programme
Utilization Period: 1992 to 2015
Last update: 2019-11-14
Detailed characteristics
No. Central frequency (GHz) Bandwidth (MHz) Polarisation NEΔT
4 91.655 ± 1.250 3000 H 0.6 K
5 150.0 ± 1.250 1500 H 0.6 K
3 183.31 ± 7.0 500 H 0.6 K
1 183.31 ± 3.0 1000 H 0.6 K
2 183.31 ± 1.0 1500 H 0.8 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 microwave radiometer
  • Cross-track, special or non-scanning microwave radiometer
Mission objectives
Primary mission objectives
  • Specific humidity
Secondary mission objectives
  • Cloud ice Total Column
  • Cloud liquid water (CLW) total column
  • Integrated Water Vapour (IWV)
  • Precipitation intensity at surface (liquid or solid)
Show allShow fewer
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
Cloud drop effective radius2 - very highNo specific limitation.MW channels around 90 GHz, and in 183 GHz band
Cloud ice3 - highNo specific limitation.MW channels around 90 GHz, and in 183 GHz band
Cloud ice Total Column3 - highNo specific limitation.MW channels around 90 GHz, and in 183 GHz band
Cloud ice effective radius2 - very highNo specific limitation.MW channels around 90 GHz, and in 183 GHz band
Cloud liquid water (CLW)3 - highNo specific limitation.MW channels around 90 GHz, and in 183 GHz band
Cloud liquid water (CLW) total column3 - highNo specific limitation.MW channels around 90 GHz, and in 183 GHz band
Downward long-wave irradiance at Earth surface5 - marginalHighly indirect.MW channels in 183 GHz band to account for downward cloud radiation
Precipitation intensity at surface (liquid or solid)5 - marginalNo specific limitation.MW channels in the 183 GHz band. Suitable for solid precipitation over sea and land, Insensitive to surface emissivity
Specific humidity3 - highCoarse vertical resolution.MW channels in the 183 GHz band
Integrated Water Vapour (IWV)2 - very highNo specific limitation.MW channels in the water vapour band around 183 GHz
Upward long-wave irradiance at Earth surface5 - marginalHighly indirect.MW channels is the 183 GHz band to infer the impact of clouds on the upward LW radiation