BackForwardInstrument:  HYMS 

Instrument details
Acronym HYMS
Full name Hyperspectral Microwave Sounder
Purpose To provide low noise microwave radiances for NWP in a compact instrument aiming to reduce the cost of traditional MW sounders.
Short description

A hyperspectral microwave radiometer centred on 6 spectral regions to sound the atmospheric temperature and water vapour profiles from 54 to 183 GHz. Details in table below. About each centre frequency the spectrum is sampled at high spectral resolution within the bandwidth specified.
Background

This is a new development funded by UKSA and Spire.
Scanning Technique

Cross-track +/- 49 deg
Resolution 24 km at 50 GHz 17 km at 183 GHz
Coverage / Cycle Global with 2 passes a day.
Mass 20 kg Power 100 W Data Rate

 

Providing Agency UKSA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 2024 to 2027
Last update: 2025-04-14
Detailed characteristics
Channel No. Frequency GHz Bandwidth MHz Footprint km at nadir NeDT (K)
1 54 156 24 0.28
2 54 64 24 0.43
3 54 32 24 0.61
4 54 12 24 1.00
5 89 3000 18 0.14
6 183 500 18 0.35
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
WIGOS Subcomponents
  • Subcomponent 3
  • Hyperspectral MW sensors
  • Hyperspectral MW radiometer
Mission objectives
Primary mission objectives
  • Atmospheric temperature
  • Specific humidity
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 - highVery coarse vertical resolution.A few MW channels in the 54 GHz band. Nearly all-weather sounding
Cloud drop effective radius5 - marginalHighly indirect.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 radius3 - 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
Freezing level height in clouds4 - fairNo specific limitation.MW channels in the 54 GHz band. Inference from the temperature profile
Melting layer depth in clouds4 - fairNo specific limitation.MW channels in the 54 GHz band. Inference from the temperature profile
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 humidity*3 - 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