The Special Sensor Microwave Imager/Sounder (SSMIS) is a passive microwave conically scanning imager and sounder. SSMIS instruments are aboard the Defense Meteorological Satellite Program (DMSP) satellites, beginning with F-16. SSMIS improves upon the surface and atmospheric retrievals of the previous Special Sensor Microwave Imager (SSM/I). The instrument also builds on the success of the atmospheric temperature and water vapor sounding capabilities of both the Special Sensor Microwave Temperature Sounder (SSM/T-1) and the Special Sensor Microwave Humidity Sounder (SSM/T-2). 

The SSMIS imaging and sounding instruments can estimate atmospheric temperature, moisture, and surface parameters. These data can be used in studies of sea surface winds, rain rates, cloud water, precipitation, soil moisture, ice edge, and ice age.