Articles | Volume 30, issue 3
https://doi.org/10.5194/hess-30-629-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hess-30-629-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Feb 2026
Research article |
| 04 Feb 2026
| 04 Feb 2026
When physics gets in the way: an entropy-based evaluation of conceptual constraints in hybrid hydrological models
Manuel Álvarez Chaves
CORRESPONDING AUTHOR
Stuttgart Center for Simulation Science, Cluster of Excellence EXC 2075, University of Stuttgart, 70569 Stuttgart, Germany
Eduardo Acuña Espinoza
Institute of Water and Environment, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
Uwe Ehret
Institute of Water and Environment, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
Anneli Guthke
Stuttgart Center for Simulation Science, Cluster of Excellence EXC 2075, University of Stuttgart, 70569 Stuttgart, Germany
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Short summary
This study evaluates hybrid hydrological models combining physics-based and data-driven components, using Information Theory to measure their relative contributions. When testing conceptual models with Long Short-Term Memory (LSTM) networks that adjust parameters over time, we found performance primarily comes from the data-driven component, with physics constraints adding minimal value. We propose a quantitative tool to analyse this behaviour and suggest a workflow for diagnosing hybrid models.
This study evaluates hybrid hydrological models combining physics-based and data-driven...
