An orbiting micro-wave imager

The Imaging Microwave Radiometer (IMR) Phase A study results presented draw attention to this instrument's technical feasibility. Although similar to the Scanning Multichannel Microwave Radiometer aboard Nimbus 7, and the Large Aperture Multichannel Microwave Radiometer which is currently under consideration (whose 4 m antenna offers excellent spatial resolution), the IMR promises radiometric resolution superior to those of these systems. The IMR is able to measure the intensity of radiation in the microwave band at a number of specific frequencies. By means of a complex data retrieval process, underlying surface characteristics may be extracted from these measurements. The parameters made accessible in this way include sea surface temperature, surface wind speed, sea ice cover, land snow cover, cloud liquid water content, and rain rate.