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Microwave Imagery Products
The DMSP Microwave Imager contains a passive microwave radiometer that measures the thermal energy emitted and reflected by the Earth's atmosphere using the microwave portion of the electromagnetic spectrum. The sensor measures microwave energies at four frequencies: 19.35 GHz, 22.235 GHz, 37.0GHz, and 85.5 GHz. Both vertical and horizontal polarizations are used, except for 22.235 GHz, where one polarization is adequate. Various combinations of the seven channels are used to derive precipitation rates, water content in clouds and soil, land types, temperature, and wind speeds. The figure below is a multispectral image from the DMSP OL-S sensor showing Hurricane Seth in its later stages; the figures that follow show the corresponding microwave products. 
Multispectral OL-S Imagery of Hurricane Seth The Photo below shows the surface wind speeds for Hurricane Seth. Here the land masses are shown in black. The highest winds are between 35 and 49 knots, depicted in red.
Cloud water is another parameter that can be determined. Cloud water is defined as droplets 0.1 mm or larger in diameter. The next photo shows the cloud water in the hurricane.
The next photo shows precipitation at the same time as the wind and cloud water above. This image indicates that rainfall of up to 13 mm/hr is falling over a wide area. The yellow around the islands is due to shoreline contamination.
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