Special sensor microwave temperature
From Glossary of Meteorology
Special Sensor Microwave Temperature
(Abbreviated SSM/T.) The microwave temperature and water vapor sounders on the DMSP polar-orbiting satellites.
SSM/T is a temperature sounder, while SSM/T2 is a water vapor profiler. Many of the capabilities of the SSM/T and SSM/T2 instruments will be duplicated on the AMSU.