Brief communication: Estimation of hydraulic properties of active layers using ground-penetrating radar (GPR) and 2D inverse hydrological modeling

Abstract. Estimation of hydraulic properties of active layers is challenging due to the freeze-thaw effect in space and time. Provided an active layer with an undulating thawing table, monitoring of spatial soil water dynamics could provide significant information for commonly-used inverse estimation of soil hydraulic properties. In this study, we assess the feasibility of efficiently estimating soil hydraulic properties using Ground-Penetrating Radar (GPR) observations – soil water storage and layer thickness in conjunction with a two-dimensional hydrological model. The results of this study conceptually demonstrate that spatial and temporal observations of soil moisture in the active layer during a rain event are sufficient for inverse estimation of soil hydraulic parameters. The proposed method depends on the lateral water redistribution controlled by the undulating frost table and/or the intensity and duration of the precipitation. We suggest that this method could be used for seasonal-scale estimation of soil hydraulic properties.