Comment on ‘L. Ciarapica and E. Todini, TOPKAPI: a model for the representation of the rainfall – runoff process at different scales. Hydrological Processes 16 (2002) 207 – 229’

✍ Scribed by Jérôme Latron; Francesc Gallart; Pilar Llorens

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 61 KB
• Volume: 18
• Category: Article
• ISSN: 0885-6087
• DOI: 10.1002/hyp.1311

✦ Synopsis

introduced a new physically based, but parsimonious in parameterization, rainfall-runoff model that can take both distributed and lumped versions. The main advantage claimed for this model is that it may be applied to a large range of spatial scales without losing the physical meaning of the model and parameters. The parameters may be derived from soil and land-use maps, although some calibration with discharge data is necessary if soil information is scarce.

Within the paper, the authors presented the application of the TOPKAPI model to three different catchments of increasing size to demonstrate the applicability of the model to a large range of spatial scales. The smallest catchment used for model evaluation is the Can Vila catchment (0Ð56 km 2 ), one of the several research catchments in the Vallcebre area (Spanish Pyrenees) that have been managed by the Institute of Earth Sciences 'Jaume Almera' since 1989. This application of the TOPKAPI model to the Can Vila catchment was performed within the EU funded VAHMPIRE project , which aimed to evaluate the performance of several hydrological models through a split-sample calibration-evaluation exercise. The modelling teams were provided with catchment characteristic data as well as precipitation, reference evapotranspiration and discharge data for a calibration period, and input data for a further evaluation period. Model simulation results obtained for both calibration and evaluation periods were analysed initially by the field working team.

Modelling works on Mediterranean catchments, using a great variety of approaches, have developed significantly during the past 10 years (see for a brief review). This variety may be in relation with the difficulties associated with modelling dry catchments noted by . The difficulty of modelling the Mediterranean or semi-arid catchments is often exacerbated by the scarcity of data, as noted by . In this context, the TOPKAPI model based on a simple and parsimonious parameterization appears to be an interesting approach.

In our view, however, the few results presented by Ciarapica and Todini for the Can Vila catchment are insufficient to evaluate thoroughly the performance of the application of the TOPKAPI model to this catchment. The aim of this comment is not, however, to feed the existing debate (e.g.