Articles | Volume 29, issue 21
https://doi.org/10.5194/hess-29-6157-2025
© Author(s) 2025. 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-29-6157-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Nov 2025
Research article |
| 11 Nov 2025
| 11 Nov 2025
Error-correction across gauged and ungauged locations: A data assimilation-inspired approach to post-processing river discharge forecasts
Gwyneth Matthews
CORRESPONDING AUTHOR
Department of Meteorology, University of Reading, Reading, United Kingdom
European Centre for Medium-range Weather Forecasts, Reading, United Kingdom
Hannah L. Cloke
Department of Meteorology, University of Reading, Reading, United Kingdom
Department of Geography and Environmental Science, University of Reading, Reading, United Kingdom
Sarah L. Dance
Department of Meteorology, University of Reading, Reading, United Kingdom
Department of Mathematics and Statistics, University of Reading, Reading, United Kingdom
National Centre for Earth Observation (NCEO), Reading, United Kingdom
Christel Prudhomme
European Centre for Medium-range Weather Forecasts, Reading, United Kingdom
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Short summary
Forecasts provide information crucial for managing floods and for water resource planning, but they often have errors. “Post-processing” reduces these errors but is usually only applied at river gauges, leaving areas without gauges uncorrected. We developed a new method that uses spatial information contained within the forecast to spread information about the errors from gauged locations to ungauged areas. Our results show that the method successfully makes river forecasts more accurate.
Forecasts provide information crucial for managing floods and for water resource planning, but...
