Abstract
Abstract. Water fluxes at the soil–atmosphere interface are a key piece of information for studying the terrestrial water cycle. However, measuring and modeling water fluxes in the vadose zone poses great challenges. While direct measurements require costly lysimeters, common soil hydrologic models rely on a correct parametrization, a correct representation of the involved processes, and the selection of correct initial and boundary conditions. In contrast to lysimeter measurements, soil moisture measurements are relatively cheap and easy to perform. Using such measurements, data-driven approaches offer the possibility to derive water fluxes directly. Here we present FluSM (fluxes from soil moisture measurements), which is a simple, parsimonious and robust data-driven water balancing framework. FluSM requires only a single input parameter (the infiltration rate) and is especially valuable for cases where the application of Richards-based models is critical. Since permeable pavements (PPs) present such a case, we apply FluSM on a recently published soil moisture data set to obtain the water balance of 15 different PPs over a period of 2 years. Consistent with findings from previous studies, our results show that vertical drainage dominates the water balance of PPs, while surface runoff plays only a minor role. An additional uncertainty analysis demonstrates the ability of the FluSM-approach for water balance studies, since input and parameter uncertainties only have a small effect on the characteristics of the derived water balances. Due to the lack of data on the hydrologic behavior of PPs under field conditions, our results are of special interest for urban hydrology.
Highlights
Soil moisture controls the partitioning of energy and water fluxes at the ground surface and is of major importance for understanding and modeling the terrestrial water cycle (Eagleson, 1978; Lahoz and De Lannoy, 2014; Trenberth and Asrar, 2014; Vereecken et al, 2015)
Such measurements have been used in different ways for modeling of water movement within the vadose zone, which is of major interest for understanding the terrestrial water cycle on different spatial scales
We presented the data-driven water balance framework FluSM, which allows us to derive water fluxes directly from soil moisture and meteorological measurements
Summary
Soil moisture controls the partitioning of energy and water fluxes at the ground surface and is of major importance for understanding and modeling the terrestrial water cycle (Eagleson, 1978; Lahoz and De Lannoy, 2014; Trenberth and Asrar, 2014; Vereecken et al, 2015). Long-term, high-resolution soil moisture data become increasingly available for studying soil hydrological processes (Vereecken et al, 2015). Such measurements have been used in different ways for modeling of water movement within the vadose zone, which is of major interest for understanding the terrestrial water cycle on different spatial scales. Richards-based models may be inappropriate for fields where it is difficult to determine representative soil hydraulic parameters and where the exact representation of different soil hydrological processes is unclear.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
