Surface resistance calibration for a hydrological model using evapotranspiration retrieved from remote sensing data in Nahe catchment forest area
- 1Department of Physical Geography, University of Trier, Campus II, 54286 Trier, Germany
- 2Geoinformatics and Remote Sensing, Institute for Geography, University of Leipzig, Johannisallee 19a, 04103 Leipzig, Germany
Keywords: Surface resistance calibration, distributed hydrological model WaSiM-ETH, evapotranspiration, remote sensing images, soil water conditions
Abstract. In this paper, a method combining graphical and statistical techniques is proposed for surface resistance calibration in a distributed hydrological model, WaSiM-ETH, by comparing daily evapotranspiration simulated by model WaSiM-ETH with corresponding daily evapotranspiration retrieved from remote sensing images. The study area locates in Nahe catchment (Rhineland-Palatinate, Germany, 4065 km2) forest regions. The remote sensing based observations are available for a very limited number of days but representative for most soil moisture conditions. By setting canopy resistance (rc) at 150 s/m, soil surface resistance (rse) at 250 s/m or at 300 s/m for deciduous forest and setting rc at 300 s/m, rse at 600 s/m or at 650 s/m for pine forest, the model exhibits its best overall performance in space and time. It is also found that with sufficient soil moisture, the model exhibits its best performance in space scale.