Estimation of the parameters of an isolated event conceptual model from physical catchment characteristics

Abstract

There has been a trend in recent years towards the development and popularity of physically-based deterministic models. However, the application of such models is not without difficulties. This paper investigates the usefulness of a conceptual single-event model for simulating floods from catchments covering a wide variety of climatic and physiographic areas. The model has been calibrated on a group of catchments and the calibrated parameter values related to physical catchment indices. The resulting quantitative relationships are assessed with respect to their value for estimating the parameter values of the model when calibration is not possible. The results indicate that the technique is likely to provide flood estimations for medium sized catchments (5-150 km 2 ) that are more reliable than several flood estimation methods currently in use in South Africa. Estimation des paramètres d'un modèle conceptuel pour une événement isolé d'après les caractéristiques d'un bassin physiqueRésumé Ces dernières années ont vu une tendance vers le développement et la popularité des modèles déterministes à bases physiques. Cependant, l'application de tels modèles n'est pas sans présenter quelques difficultés. Cet article cherche les possibilités d'utilisation d'un modèle conceptuel pour un événement isolé pour simuler les crues provenant des bassins qui couvrent une grande variété de zones climatiques et physiographiques. Le modèle a été calibré sur un groupe de bassins et les valeurs paramétriques calibrées ont été apparentées aux indices physiques des bassins. Les relations quantitatives en résultant sont étudiées selon leur valeur pour estimer les valeurs des paramètres du modèle quand la calibration n'est pas possible. Les résultats indiquent que la technique doit pouvoir donner des estimations de débits de crues pour des bassins de taille moyenne (de 5 km 2 à 150 km 2 ) qui sont plus fiables que plusieurs méthodes d'estimation de débits de crues couramment utilisées en Afrique du Sud.

Selection of conceptual models for regionalisation of the rainfall-runoff relationship

“…However, in practice, data support is limited, and many of the required physical properties are unobservable at model grid scale, and cannot be adequately calibrated using typically available rainfall-runoff data. These and other limitations are well-known (Beven, 1989(Beven, , 2001Hughes, 1989;Binley et al, 1991;Beven and Binley, 1992;Wheater, 2002), and currently preclude realistic application to ungauged catchments. As noted above, metric models have been restricted by the constraints of relatively simple model structures, and recent developments, such as neural network models, are not obviously amenable to regionalisation.…”

“…Attempts to define catchment similarity have been based on geographical closeness (Mosley, 1981;Hughes, 1989). Vandewiele and Elias (1995) based their study on catchment grouping of geographically continuous areas, even though neighbouring catchments within a region may be physically and hydrologically very different.…”

Application of Conceptual Rainfall-Runoff Model METQ for Simulation of Daily Runoff and Water Level: The case of the Lake Burtnieks Watershed

“…Then parameter sets can be compiled for ungauged catchments from measurable variables. During the past decades this approach has been tested by several scientists with varying success (Hughes, 1989;Servat and Dezetter, 1993;Braun and Renner, 1992;Ibrahim andCordery, 1995, Seibert, 1999;Merz and Blöschl, 2004;Parajka et al, 2005;Götzinger and Bárdossy, 2007). Seibert (1999) concluded that the general problem in the regionalisation of model parameters is the limited number of catchments usually available and that model parameters often are badly defined.…”

Developing sustainable water management scenarios by using thorough hydrologic analysis and environmental criteria

“…Many scientists have attempted to calculate some of these parameters in ungauged basins by using regression techniques (Jarboe and Haan, 1974) or by implementing conceptual models with high parameterization (Hughes, 1989). These approaches may provide credible results in site-specific cases but they are not widely applicable, since they incorporate significant amount of uncertainty.…”