BackForwardInstrument:  MATHS 

Instrument details
Acronym MATHS
Full name Millimetre wave Atmospheric Temperature and Humidity Sounder
Purpose Temperature and Humidity sounding in almost all-weather conditions.  Also precipitation rate.
Short description

A 20-channel cross-track scanning Radiometer operating at 50-60 GHz and 183.31± 16.25GHz bands. See table below.
Background

A new development
Scanning Technique

Cross-track scanning. 
Resolution Temperature sounding channels have nadir spatial resolution of 25 km. Humidity sounding channels 15 km.
Coverage / Cycle Near-global coverage twice/day
Mass Power Data Rate

 

Providing Agency ISRO
Instrument Maturity Flown on operational programme
Utilization Period: 2025 to 2030
Last update: 2025-03-24
Detailed characteristics
Number Frequency (GHz) IFOV (km)
1 50.3 25
2 51.76 25
3 52.9 25
4 53.63 25
5 54.4 25
6 54.95 25
7 55.5 25
8 56.65 25
9 57.545 25
10 58.8 25
11 59.38 25
12 56.95 25
13 59.6 25
14 58.316 25
15 183.31±1 15
16 183.31±1.8 15
17 183.31±3 15
18 183.31±4.5 15
19 183.31±7 15
20 183.31±15.75 15
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 1
  • MW sounders [in SSO]
  • MW sounder [in SSO]
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
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
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