Comparison between the lab observations and DDA computations on the backscattering features of sphere-cone-oblate ice particles

Twenty sphere-cone-oblate ice particles are simulated for their backscattering observations in a microwave lab and calculations are done with the DDA method. The lab experiment and the DDA theory are briefly presented in this paper. The theoretical results are compared with the lab observations. It is shown that the theoretical results are consistent with the experimental data in general and that the backscattering ability of sphere-cone-oblate ice particles increases as the particle size parameter increases, and fluctuates in the so-called resonance region. The backscattering cross sections of sphere-cone-oblate ice particles depend not only on their sizes equivolume spherical radii R_e but also on their shapes. There is a statistically linear relationship between differential reflectivity Z_DR and the shape factor, 2a/h, which is the ratio of the horizontal scale to the vertical scale of a particle.