Microwave radiometer

A Microwave Radiometer (MWR) is a radiometer that measures energy emitted at sub-millimetre-to-centimetre wavelengths (at frequencies of 1-1000 GHz) known as microwaves. Their primary application has been onboard spacecraft measuring atmospheric and terrestrial radiation and are almost solely used for meteorological or oceanographic remote-sensing. Their secondary application is also meteorological, but as zenith-pointing surface instruments which solely view the Earth's atmosphere in a region above the stationary instrument.

Additional recommended knowledge

Better weighing performance in 6 easy steps

Weighing the right way

Essential Laboratory Skills Guide

By understanding the physical processes associated with energy emission at these wavelengths, scientists can calculate a variety of surface and atmospheric parameters from these measurements, including air temperature, sea surface temperature, salinity, sea ice, precipitation, the total amount of water vapor and the total amount of liquid water in the atmospheric column directly above or below the instrument.

Examples of microwave radiometers on meteorological satellites include the Special Sensor Microwave/Imager, Scanning Multichannel Microwave Radiometer and Microwave Sounding Unit.