Sounder

"An instrument that measures vertical distribution of precipitation and other atmospheric characteristics such as temperature, humidity, and cloud composition." (National Aeronautics and Space Administration, 2018)

Sources

"Remote Sensors". Earthdata, National Aeronautics and Space Administration. Last modified December 11, 2018.
https://earthdata.nasa.gov/user-resources/remote-sensors.
Accessed February 13, 2019.