Drone-Borne Ground-Penetrating Radar for Snow Cover Mapping

Ground-penetrating radar (GPR) is one of the most commonly used instruments to map Snow Water Equivalent (SWE) in mountainous regions. However, some areas may be difficult or dangerous access; besides, surveys can quite time-consuming. We test a new system fulfill need speed up acquisition process for analysis SWE and access remote areas. A GPR antenna (900 MHz) mounted on drone prototype designed carry heavy instruments, fly safely at high altitudes, avoid interference signal. survey two sites Alpine region during winter 2020–2021 presented, check performance mapping snow thickness catchment scale. data according standard flow-chart processing we pick both travel times air–snow interface snow–ground compute time difference estimate depth. The calibration depth performed by comparing with measurements preselected stations. main results show fairly good reliability terms quality, accuracy, spatial resolution monitoring. tested device condition low density (<200 kg/m3) this limits detectability interface. This mainly caused values electrical permittivity dry soft snow, providing weak reflectivity surface. To overcome critical aspect, use rangefinder properly detect snow–air sensor already installed our commercial drones flight purposes. Based experience prototype, various improvement strategies limitations drone-borne are discussed. In conclusion, technology found ready support GPR-based applications provided that operators acquire adequate knowledge devices, order effectively build, tune, maintain reliable system.