A high spatial resolution 95 GHz polarimetric radar for remote sensing clouds.

摘要

A high power 95 GHz polarimetric airborne radar was fabricated at the University of Massachusetts to remotely sense clouds. The high operating frequency allows the radar to image the backscatter and polarization characteristics of clouds with spatial resolutions as small as 1m x 1m at 85m ranges and 10m x 10m at 1km ranges. In March 1992 the radar participated in a cooperative experiment with the University of Wyoming to observe the polarimetric characteristics of ice particles in a ground-based experiment at the University of Wyoming's Elk Mountain observatory. In November 1992 a series of aircraft experiments was conducted in which the radar measured high spatial resolution images of the co- and cross-polarized reflectivity and Doppler spectrum mean and standard deviation for a wide range of cloud particle types and precipitation processes. In-situ measurements of the weather conditions and cloud particle characteristics were made simultaneously during both experiments. This dissertation describes the polarimetric radar system used in the experiments, presents experimental results and discusses the radar's ability to detect and display fine-scale variations in particle phase, cloud structure and motion.