Advanced Microwave Sounding Unit

The Advanced microwave sounding unit (AMSU) is a multi-channel microwave radiometer installed on meteorological satellites. The instrument examines several bands of microwave radiation from the atmosphere to perform atmospheric sounding of temperature and moisture levels.

Level-1 radiance data are calibrated brightness temperatures.

Level-2 geophysical data from AMSU include:

AMSU data is also used together with infrared radiances from HIRS, AIRS, or IASI to produce blended MW/IR level-2 geophysical products such as:

AMSU data is used extensively in weather prediction. Brightness temperatures are processed as quickly as possible and sent to numerical weather prediction (NWP) centers around the world. This data helps keep the assessment of the current state of the atmosphere correct, which in turn helps make predictions more accurate.

Long-term AMSU records are also used in studies of climate.

AMSU-A + AMSU-B have flown together on the 3 NOAA KLM satellites: NOAA-15 (NOAA K), launched May 13, 1998; NOAA-16 (NOAA L), launched September 21, 2000; and NOAA-17 (NOAA M), launched June 24, 2002.

For NOAA-18 (NOAA N), launched May 20, 2005, AMSU-B was replaced by a similar instrument, the Microwave Humidity Sounder (MHS).

Versions of AMSU-A also fly on the NASA Aqua Earth science satellite and the EUMETSAT MetOp series. On these spacecraft, AMSU-B is replaced by similar microwave humidity sounders: HSB for Aqua and MHS for MetOp.

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