TIROS Operational Vertical Sounder (TOVS)
The TIROS Operational Vertical Sounder (TOVS) system consisted of three instruments: the High Resolution Infrared Radiation Sounder Version 2 (HIRS/2), the Microwave Sounding Unit (MSU) and the Stratospheric Sounding Unit (SSU). This system was onboard the NOAA-6 through NOAA-14 and TIROS-N satellites. The Advanced TOVS (ATOVS) replaced the TOVS instruments starting from NOAA-15 onwards. It consists of HIRS/3, the Advanced Microwave Sounding Unit-A (AMSU-A) and AMSU-B.
The Microwave Humidity Sounder (MHS), developed by EUMETSAT, replaced AMSU-B on NOAA-18 and the European MetOp satellites. Currently the ATOVS is generating products from the NOAA-15, 16, 18 and METOP-A satellites. This instrument package provides information on temperature and humidity profiles, total ozone, clouds and radiation on a global scale.