| Title: | Calibration and uncertainty issues of a hydrological model (SWAT) applied to West Africa |
| Authors: | Schuol, J. and K.C. Abbaspour |
| Year: | 2006 |
| Journal: | Advances in Geosciences |
| Volume (Issue): | 9 |
| Pages: | 137-143 |
| Article ID: | |
| DOI: | 10.5194/adgeo-9-137-2006 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | calibration, sensitivity, and/or uncertainty analysis |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 4 million km^2 drainage area, including the Niger, Volta and Senegal Rivers, that comprise the West African subcontinent. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Distributed hydrological models like SWAT (Soil and Water Assessment Tool) are often highly over-parameterized, making parameter specification and parameter estimation inevitable steps in model calibration. Manual calibration is almost infeasible due to the complexity of large-scale models with many objectives. Therefore we used a multi-site semi-automated inverse modelling routine (SUFI-2) for calibration and uncertainty analysis. Nevertheless, the question of when a model is sufficiently calibrated remains open, and requires a project dependent definition. Due to the non-uniqueness of effective parameter sets, parameter calibration and prediction uncertainty of a model are intimately related. We address some calibration and uncertainty issues using SWAT to model a four million km^2 area in West Africa, including mainly the basins of the river Niger, Volta and Senegal. This model is a case study in a larger project with the goal of quantifying the amount of global country-based available freshwater. Annual and monthly simulations with the "calibrated" model for West Africa show promising results in respect of the freshwater quantification but also point out the importance of evaluating the conceptual model uncertainty as well as the parameter uncertainty. |
| Language: | English |
| Keywords: | |