Articles | Volume 30, issue 9
https://doi.org/10.5194/hess-30-2797-2026
© 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-30-2797-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 May 2026
Research article |
| 11 May 2026
| 11 May 2026
Multivariate calibration can increase simulated discharge uncertainty and model equifinality
Department Water Resources and Drinking Water, Eawag – Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
Department of Infrastructure Engineering, Faculty of Engineering and Information Technology, University of Melbourne, Melbourne, VIC, Australia
Keirnan Fowler
Department of Infrastructure Engineering, Faculty of Engineering and Information Technology, University of Melbourne, Melbourne, VIC, Australia
Hansini Gardiya Weligamage
Department of Infrastructure Engineering, Faculty of Engineering and Information Technology, University of Melbourne, Melbourne, VIC, Australia
Murray Peel
Department of Infrastructure Engineering, Faculty of Engineering and Information Technology, University of Melbourne, Melbourne, VIC, Australia
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Short summary
Multivariate calibration has become a widely used method to improve model realism. We found that multivariate calibration can lead to less constrained flux maps and more uncertain hydrographs relative to univariate calibration. These symptoms could be caused by non-overlapping behavioural parameter distributions for the individual calibration variables. The results emphasize that the value of non-discharge data in calibration is contingent on the suitability of the model structure.
Multivariate calibration has become a widely used method to improve model realism. We found that...
