Articles | Volume 24, issue 6
https://doi.org/10.5194/nhess-24-2147-2024
© 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-24-2147-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
27 Jun 2024
Research article | Highlight paper |
| 27 Jun 2024
| 27 Jun 2024
A downward-counterfactual analysis of flash floods in Germany
Institute of Environmental Science and Geography, University of Potsdam, Potsdam, Germany
Maik Heistermann
Institute of Environmental Science and Geography, University of Potsdam, Potsdam, Germany
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Floods have caused significant damage in the past. To prepare for such events, we rely on historical data but face issues due to rare rainfall events, lack of data and climate change. Counterfactuals, or
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Cosmic-ray neutron sensing (CRNS) is a non-invasive technique used to obtain estimates of soil water content (SWC) at a horizontal footprint of around 150 m and a vertical penetration depth of up to 30 cm. However, typical CRNS applications require the local calibration of a function which converts neutron counts to SWC. As an alternative, we propose a generalized function as a way to avoid the use of local reference measurements of SWC and hence a major source of uncertainty.
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Maik Heistermann, Till Francke, Martin Schrön, and Sascha E. Oswald
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Cosmic-ray neutron sensing (CRNS) is a powerful technique for retrieving representative estimates of soil moisture in footprints extending over hectometres in the horizontal and decimetres in the vertical. This study, however, demonstrates the potential of CRNS to obtain spatio-temporal patterns of soil moisture beyond isolated footprints. To that end, we analyse data from a unique observational campaign that featured a dense network of more than 20 neutron detectors in an area of just 1 km2.
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Executive editor
The paper addresses a highly relevant and topical question in flood risk management. The method and results are an innovative and interesting contribution to the field of research which merits information to the broader public and media.
The paper addresses a highly relevant and topical question in flood risk management. The method...
Short summary
To identify flash flood potential in Germany, we shifted the most extreme rainfall events from the last 22 years systematically across Germany and simulated the consequent runoff reaction. Our results show that almost all areas in Germany have not seen the worst-case scenario of flood peaks within the last 22 years. With a slight spatial change of historical rainfall events, flood peaks of a factor of 2 or more would be achieved for most areas. The results can aid disaster risk management.
To identify flash flood potential in Germany, we shifted the most extreme rainfall events from...
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