WMO OSCAR | Details for Instrument GMI (constellation)

No JavaScript detected
Usage of this Website will be severly limited without JavaScript. Please enable JavaScript in your Browser.

Instrument: GMI (constellation)

Instrument details

Acronym	GMI (constellation)
Full name	GPM Microwave Imager
Purpose	Multi-purpose imager, with emphasis on precipitation
Short description	8 frequencies / 13 channels [see detailed characteristics below]
Background	Similar to GMI on GPM-core but operating in higher altitude and low-inclination orbit
Scanning Technique	Conical: 53° zenith angle; useful swath: 1300 km - Scan rate: 32 scan/min = 12.8 km/scan
Resolution	Changing with frequency, consistent with an antenna diameter of 1.2 m (only partially illuminated at higher frequencies)
Coverage / Cycle	Intertropical coverage, several sequences of passes at ~ 100-min intervals with longer gaps once or twice per day; more regular coverage at 15°N and 15°S
Mass	150 kg	Power	140 W	Data Rate	25 kbps

Providing Agency	NASA
Instrument Maturity	Backed by strong heritage
Utilization Period:	TBD
Last update:	2017-03-29

Detailed characteristics

Central frequency (GHz)	Bandwidth (MHz)	Polarisations	NEΔT	IFOV	Pixel
10.65	100	V, H	0.96 K	30x50 km	24x12.8 km
18.7	200	V, H	0.84 K	17x29 km	12x12.8 km
23.8	400	V	1.05 K	14x24 km	12x12.8 km
36.5	1000	V, H	0.65 K	13x22 km	6.0x12.8 km
89.0	6000	V, H	0.87 K	6.9x11 km	3.0x12.8 km
166.0	3000	V, H	1.5 K	6.9x11 km	3.0x12.8 km
183.31 ± 3	3500	V	1.5 K	6.9x11 km	3.0x12.8 km
183.31 ± 7	4500	V	1.5 K	6.9x11 km	3.0x12.8 km

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
Conical scanning microwave radiometer

WIGOS Subcomponents

Subcomponent 1
MW sounder and imagery in inclined orbits
MW sounder and imager in inclined orbits

Mission objectives

Primary mission objectives

Precipitation intensity at surface (liquid or solid)
Wind speed (near surface)

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.

Search:

Variable	Relevance for measuring this variable	Operational limitations	Explanation
Integrated Water Vapour (IWV)	1 - primary	No specific limitation.	MW channel(s) in the water vapour bands around 23 and 183 GHz
Cloud liquid water (CLW)	2 - very high	No specific limitation.	MW channels around 37 and 90 GHz, and in 183 GHz band
Cloud liquid water (CLW) total column	2 - very high	No specific limitation.	MW channels around 37 and 90 GHz, and in 183 GHz band
Snow status (wet/dry)	2 - very high	Coarse spatial resolution.	MW channels around 19, 37 and 90 GHz. Higher frequencies less sensitive to emissivity from ground under snow
Snow water equivalent	2 - very high	Coarse spatial resolution.. Ground stations network needed.	MW channels around 19, 37 and 90 GHz. Higher frequencies less sensitive to emissivity from ground under snow
Snow cover	3 - high	Coarse spatial resolution.	MW channels around 19, 37 and 90 GHz. Higher frequencies less sensitive to emissivity from ground under snow
Soil moisture at surface	3 - high	Coarse spatial resolution.. Strongly affected by vegetation.	MW channels around 10 GHz
Wind speed (near surface)*	3 - high	Over sea only.	MW channels around 10, 19 and 37 GHz
Accumulated precipitation	4 - fair	Poor time sampling.. Time sampling to be interpolated by GEO.	MW channels around 10, 19, 23, 37 and 90 GHz
Long-wave Earth surface emissivity	4 - fair	Long time series needed.	MW channels around 10, 19, 37 and 90 GHz. Emissivity across this MW range inferred by statistical analysis
Precipitation intensity at surface (liquid or solid)*	4 - fair	No specific limitation.	MW channels around 10, 19, 23, 37 and 90 GHz, to cover sea and land, heavy and light precipitation
Land surface temperature	5 - marginal	Coarse spatial resolution.	MW channels around 10 GHz
Sea surface temperature	5 - marginal	Warm temperature only.	MW channels around 10 GHz

Showing 1 to 13 of 13 entries