AMSU

AMSU stands for the Advanced Microwave Sounding Unit. It was a series of passive microwave instruments developed by NASA and launched on board several NOAA (National Oceanic and Atmospheric Administration) weather satellites, starting with NOAA-15 in 1998. The primary purpose of AMSU was to measure atmospheric temperature and moisture profiles. It operated by detecting microwave radiation emitted by oxygen and water vapor in the Earth's atmosphere at various frequencies. These measurements allowed scientists to infer temperature at different altitudes, from near the surface up to the stratosphere, and also to determine the amount of water vapor present.

The AMSU instrument suite typically consisted of multiple components, with AMSU-A and AMSU-B being the most common. AMSU-A focused on temperature sounding, utilizing channels sensitive to oxygen emissions. AMSU-B, on the other hand, was designed for moisture sounding and collected data in frequency ranges sensitive to water vapor and liquid water. The data generated by AMSU played a crucial role in numerical weather prediction models, improving forecasts of weather patterns and climate. The instruments provided continuous, global observations, contributing significantly to our understanding of atmospheric dynamics and climate change. AMSU instruments were operational on several NOAA satellites until their eventual replacement by subsequent generations of microwave sounders.

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