Investigation of the transferability of hydrological models and a method to improve model calibration

Abstract

Abstract. In order to find a model parameterization such that the hydrological model performs well even under different conditions, appropriate model performance measures have to be determined. A common performance measure is the Nash Sutcliffe efficiency. Usually it is calculated comparing observed and modelled daily values. In this paper a modified version is suggested in order to calibrate a model on different time scales simultaneously (days up to years). A spatially distributed hydrological model based on HBV concept was used. The modelling was applied on the Upper Neckar catchment, a mesoscale river in south western Germany with a basin size of about 4000 km 2 . The observation period 1961-1990 was divided into four different climatic periods, referred to as "warm", "cold", "wet" and "dry". These sub periods were used to assess the transferability of the model calibration and of the measure of performance. In a first step, the hydrological model was calibrated on a certain period and afterwards applied on the same period. Then, a validation was performed on the climatologically opposite period than the calibration, e.g. the model calibrated on the cold period was applied on the warm period. Optimal parameter sets were identified by an automatic calibration procedure based on Simulated Annealing. The results show, that calibrating a hydrological model that is supposed to handle short as well as long term signals becomes an important task. Especially the objective function has to be chosen very carefully.

Analyzing catchment behavior through catchment modeling in the Gilgel Abay, Upper Blue Nile River Basin, Ethiopia

“…Hartmann and Bárdossy, 2005). The tests showed good performance in both catchments with R eff of about 0.80 in the two sub-catchments and low Q values.…”

On the lack of robustness of hydrologic models regarding water balance simulation: a diagnostic approach applied to three models of increasing complexity on 20 mountainous catchments

“…A review of the authors discussing this issue in hydrology includes Wagener et al (2003), Hartmann and Bárdossy (2005), Son and Sivapalan (2007) 2012), Gharari et al (2013) and Zhan et al (2013). Some of these studies present new calibration criteria better balancing the weight of different error types (e.g.…”

Incorporating uncertainty in hydrological predictions for gauged and ungauged basins in southern Africa

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