Subsurface Soil Moisture Observation Using Software-Defined Radar Mounted on a UAV And Comparison with Numerical EM Simulations

Surface-to-depth profiles of soil moisture are among the most important Earth system variables due to their strong influence on the partitioning of the water cycle [1] . Yet, our directly observed knowledge of these profiles, sometimes also referred to as root-zone soil moisture (RZSM) profiles, is quite limited. Soil moisture often exhibits rapid spatial and temporal dynamics and can change significantly over a short time. For example, during the monsoon season in the US Southwest, there may be significant and sudden precipitation over localized cells.