Scattering and absorption characteristics of non-spherical cirrus cloud ice crystal particles in terahertz frequency band**Project supported by the National Natural Science Foundation of China (Grant Nos. 61527805 and 41776181).

Abstract

We used discrete dipole approximation (DDA) to examine the scattering and absorption characteristics of spherical ice crystal particles. On this basis, we studied the scattering characteristics of spherical ice crystal particles at different frequencies and non-spherical ice crystal particles with different shapes, aspect ratios, and spatial orientations. The results indicate that the DDA and Mie methods yield almost the same results for spherical ice crystal particles, illustrating the superior calculation accuracy of the DDA method. Compared with the millimeter wave band, the terahertz band particles have richer scattering characteristics and can detect ice crystal particles more easily. Different frequencies, shapes, aspect ratios, and spatial orientations have specific effects on the scattering and absorption characteristics of ice crystal particles. The results provide an important theoretical basis for the design of terahertz cloud radars and related cirrus detection methods.