Investigating the use of spatial discretization of hydrological processes in conceptual rainfall runoff modelling: a case study for the meso‐scale

Abstract

Abstract:In this study a simple modelling approach was applied to identify the need for spatial complexity in representing hydrological processes and their variability over different scales. A data set of 18 basins was used, ranging between 8 and 4011 km 2 in area, located in the Nahe basin (Germany), with daily discharge values for over 30 years. Two different parsimoniously structured models were applied in lumped as well as in spatially distributed according to two distribution classifications: (1) a simple classification based on the lithology expressed in three permeability types and (2) a more complex classification based on seven dominating runoff production processes. The objective of the study was to compare the performances of the models on a local and on a regional scale as well as between the models with a view to identifying the accuracy in capturing the spatial variability of the rainfall-runoff relationships. It was shown that the presence of a specific basin characteristic or process of the distribution classification was not related with higher model performance; only a larger basin size promoted higher model performance. The results of this study also indicated that the permeability generally contained more useful information on the spatial heterogeneity of the hydrological behaviour of the natural system than did a more detailed classification on dominating runoff generation processes. Although model performance was slightly lower for the model that used permeability as a distribution classification, consistency in its parameter values was found, which was lacking with the more complex distribution classification. The latter distribution classification had a higher flexibility to optimize towards the variability of the runoff, which resulted in higher performance, however, process representation was applied inconsistently.

Hydrological landscape classification: investigating the performance of HAND based landscape classifications in a central European meso-scale catchment

“…Based on this concept Wolock et al (2004) classified hydrological units for the entire United States of America using GIS data. Topography, land use and geology have also been used to directly infer dominant runoff processes within a catchment (Flügel, 1995;Naef et al, 2002;Schmocker-Fackel et al, 2007;Hellebrand and van den Bos, 2008;Müller et al, 2009). …”

Process‐based hydrological modelling: The potential of a bottom‐up approach for runoff predictions in ungauged catchments

“…Concerning the model structure, it is possible to discern between two distinct approaches. In an "one-size-fits-all" approach, the structure of the runoff generation module is fixed, and only the parameter set changes for each DRP (e.g., Carver et al, 2009;Haag et al, 2016;Hellebrand & van den Bos, 2008). In contrast, within a flexible framework, both structure and parameter set are developed specifically for each DRP (Hellebrand et al, 2011;Uhlenbrook et al, 2004).…”

Erosion processes on different relief units: the relationship of form and process

“…In this concept, it was assumed that process variability within the delineated unit is lower than between different units. Following this concept, more recent approaches, have led to attempts of process types regionalisation (Hellebrand and van den Bos, 2008;Müller et al, 2009;Scherrer et al, 2007).…”