Skip to Main content Skip to Navigation
Journal articles

On the potential of variational calibration for a fully distributed hydrological model: application on a Mediterranean catchment

Abstract : Calibration of a conceptual distributed model is challenging due to a number of reasons, which include fundamental (model adequacy and identifiability) and algorithmic (e.g., local search vs. global search) issues. The aim of the presented study is to investigate the potential of the variational approach for calibrating a simple continuous hydrological model (GRD; Genie Rural distributed involved in several flash flood modeling applications. This model is defined on a rectangular 1 km(2) resolution grid, with three parameters being associated with each cell. The Gardon d'Anduze watershed (543 km( )(2)) is chosen as the study benchmark. For this watershed, the discharge observations at five gauging stations, gridded rainfall and potential-evapotranspiration estimates are continuously available for the 2007-2018 period at an hourly time step. In the variational approach one looks for the optimal solution by minimizing the standard quadratic cost function, which penalizes the misfit between the observed and predicted values, under some additional a priori constraints. The cost function gradient is efficiently computed using the adjoint model. In numerical experiments, the benefits of using the distributed against the uniform calibration are measured in terms of the model predictive performance, in temporal, spatial and spatiotemporal validation, both globally and for particular flood events. Overall, distributed calibration shows encouraging results, providing better model predictions and relevant spatial distribution of some parameters. The numerical stability analysis has been performed to understand the impact of different factors on the calibration quality. This analysis indicates the possible directions for future developments, which may include considering a non-Gaussian likelihood and upgrading the model structure.
Document type :
Journal articles
Complete list of metadata

https://hal.inrae.fr/hal-03085942
Contributor : Isabelle Nault <>
Submitted on : Tuesday, December 22, 2020 - 10:33:23 AM
Last modification on : Wednesday, December 23, 2020 - 3:37:52 AM

File

Jay_HESS_2020.pdf
Publisher files allowed on an open archive

Identifiers

Citation

Maxime Jay-Allemand, Pierre Javelle, Igor Gejadze, Patrick Arnaud, Pierre-Olivier Malaterre, et al.. On the potential of variational calibration for a fully distributed hydrological model: application on a Mediterranean catchment. Hydrology and Earth System Sciences, European Geosciences Union, 2020, 24 (11), pp.5519-5538. ⟨10.5194/hess-24-5519-2020⟩. ⟨hal-03085942⟩

Share

Metrics

Record views

195

Files downloads

114