A downward structural sensitivity analysis of hydrological models to improve low-flow simulation

• Published in: Journal of hydrology (Amsterdam) Vol. 411; no. 1; pp. 66 - 76
• Main Authors: Pushpalatha, Raji, Perrin, Charles, Le Moine, Nicolas, Mathevet, Thibault, Andréassian, Vazken
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 06.12.2011; Elsevier
• Subjects: Computer simulation; Downward approach; Earth sciences; Earth, ocean, space; Exact sciences and technology; Exchange; Hydrogeology; Hydrology; Hydrology. Hydrogeology; Low flows; Lumped model; Mathematical models; Model efficiency; Representations; Sensitivity analysis; Simulation; Uncertainty; Water management; Water resources; France; Europe; Western Europe; Downward approach; Lumped model; Uncertainty; Model efficiency; Simulation; Low flows; sensitivity analysis; ground water; digital simulation; drainage basins; structural analysis; aquifers; uncertainties; performances; flow; rivers; models; efficiency; rainfall; runoff; surface water; hydrological modeling; water resource management; prediction; errors
• ISSN: 0022-1694; 1879-2707
• DOI: 10.1016/j.jhydrol.2011.09.034

► We detail a downward approach for improving a model for low-flow simulation. ► We compare several model structures on a large set of catchments and propose an improved model version. ► We compare the model with existing ones, with satisfactory results. Better simulation and earlier prediction of river low flows are needed for improved water management. Here, a top–down structural analysis to improve a hydrological model in a low-flow simulation perspective is presented. Starting from a simple but efficient rainfall–runoff model (GR5J), we analyse the sensitivity of low-flow simulations to progressive modifications of the model’s structure. These modifications correspond to the introduction of more complex routing schemes and/or the addition of simple representations of groundwater–surface water exchanges. In these tests, we wished to improve low-flow simulation while avoiding performance losses in high-flow conditions, i.e. keeping a general model. In a typical downward modelling perspective, over 60 versions of the model were tested on a large set of French catchments corresponding to various low-flow conditions, and performance was evaluated using criteria emphasising errors in low-flow conditions. The results indicate that several best performing structures yielded quite similar levels of efficiency. The addition of a new flow component to the routing part of the model yielded the most significant improvement. In spite of the close performance of several model structures, we conclude by proposing a modified model version of GR5J with a single additional parameter.