Articles | Volume 24, issue 8
https://doi.org/10.5194/nhess-24-2857-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-24-2857-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Aug 2024
Research article |
| 28 Aug 2024
| 28 Aug 2024
Are 2D shallow-water solvers fast enough for early flood warning? A comparative assessment on the 2021 Ahr valley flood event
Shahin Khosh Bin Ghomash
Section Hydrology, GFZ German Research Centre for Geoscience, Potsdam, Germany
Heiko Apel
Section Hydrology, GFZ German Research Centre for Geoscience, Potsdam, Germany
Daniel Caviedes-Voullième
CORRESPONDING AUTHOR
Simulation and Data Lab Terrestrial Systems, Jülich Supercomputing Centre, Forschungszentrum Jülich, Jülich, Germany
Institute of Bio- and Geosciences: Agrosphere (IBG-3), Forschungszentrum Jülich, Jülich, Germany
HPSC TerrSys, Geoverbund ABC/J, Jülich, Germany
Centre for Advanced Simulation and Analytics, Forschungszentrum Jülich, Jülich, Germany
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Short summary
Early warning is essential to minimise the impact of flash floods. We explore the use of highly detailed flood models to simulate the 2021 flood event in the lower Ahr valley (Germany). Using very high-resolution models resolving individual streets and buildings, we produce detailed, quantitative, and actionable information for early flood warning systems. Using state-of-the-art computational technology, these models can guarantee very fast forecasts which allow for sufficient time to respond.
Early warning is essential to minimise the impact of flash floods. We explore the use of highly...
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