Millimeter cloud radar

From Wikipedia, the free encyclopedia

Millimeter-wave cloud radar is a radar system designed to monitor cloud structure with wavelengths about ten times shorter than those used in conventional storm surveillance radars such as NEXRAD.

The National Oceanic and Atmospheric Administration designed MMCR to monitor clouds overhead at various testing sites of the U.S. Department of Energy's atmospheric radiation measurement program. The radars operate continuously at these sites in Oklahoma, Alaska and the tropical western Pacific Ocean, and are designed to function for at least ten years with minimal manned attention. The MMCR is a vertically pointing Doppler weather radar that operates at a frequency of 35 GHz. The main purpose of this radar is to determine cloud boundaries (e.g., cloud bottoms and tops). The shorter wavelength of the radar helps detect tiny water and ice droplets that conventional radars are unable to "see". The radar also helps to estimate microphysical properties of clouds, such as particle size and mass content, which aids in understanding how clouds reflect, absorb and transform radiant energy passing though the atmosphere. MMCR also reports radar reflectivity (dBZ) of the atmosphere up to 20 km. and possesses the capability to measure vertical velocities of cloud constituents.