Polarimetric observations of millimeter-wave backscatter from snowcover at 95 and 225 GHz

Two high-power millimeter-wave polarimeters, operating at 95 and 225 GHz, have been developed by the University of Massachusetts Microwave Remote Sensing Laboratory for field experimentation. Utilizing these instruments, polarimetric measurements of backscatter from snowcover were carried out between 1989-1992 for both fresh and refrozen snowcover. These data indicate that the Mueller matrix for snowcover consisting of spherical ice particles (sleet) has a relatively simple form, with ten of the sixteen elements approximately zero. Measurements of new-fallen snow consisting of predominantly nonspherical snow crystals exhibited more complex scattering behavior, fitting the general form of the Mueller matrix for natural surfaces.<>