Comparison of experimental and theoretical scattering effects from melting ice spheres at microwave and millimeter-wave frequencies

Detailed measurements of the extinction cross-section of melting hard-ice spheres have been taken using three open resonator systems operating at frequencies of 8, 10, 12, 34 and 70 GHz. Results derived theoretically for a two-layered sphere of hard-ice with an outer water shell are compared with measured values at each of the frequencies. Good agreement is obtained. Significant differences in scattering behaviour are observed from frequency to frequency with implications for propagation and remote sensing applications.