Trial of volcanic ash detection using Pi-SAR-L2

Pi-SAR-L2 data were investigated for their potential to detect areas covered by volcanic ash. Simultaneous field measurement of the dielectric constant of the ash was carried out alongside the Pi-SAR-L2 observations. The measured parameters were inserted into a semi-theoretical two-layer scattering model to describe σ⁰ from the ash-covered volcanic rocks. It was found that σ⁰ obtained using Pi-SAR-L2 was well described by this model. The model also indicates that a sensitivity of a few dB is necessary to determine the distribution of volcanic ash cover, which depends on the original surface roughness and the thickness of the ash layer.