Reflectivity modeling of eucalypt ash particles with respects to moisture absorption over microwave and millimeter wave

This paper investigates modeled reflectivity of eucalypt ash particles based on empirically measured geometric, dynamic and complex permittivity models. The eucalypt species is the most common tree genus throughout Australasia. The investigation of ash created from its foliage during bushfires is required to better understand how these particles play a role in the overall reflectivity of smoke plumes. Large smoke plumes are commonly observable on many meteorological radars. Unlike liquid precipitation which displays more homogenous like properties as effective bulk material, ash is significantly more complex. On the particle level the complex permittivity varies over the entire structure, the geometric properties are vastly complex and the internal porosity varies based on the originating cell structures. Taking these complexities in to consideration, modeled reflectivity based on statistically correct particles has been carried out in a full electromagnetic solver driven by an external software framework. The results have been analyzed and discussed.