Articles | Volume 26, issue 8
https://doi.org/10.5194/nhess-26-3863-2026
© 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/nhess-26-3863-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Aug 2026
Research article |
| 17 Aug 2026
| 17 Aug 2026
Revealing the structure of heavy precipitation events: a spatio-temporal wavelet approach
Institute of Geosciences, Section Meteorology, University of Bonn, Bonn, Germany
Sebastian Buschow
Institute of Geosciences, Section Meteorology, University of Bonn, Bonn, Germany
Petra Friederichs
Institute of Geosciences, Section Meteorology, University of Bonn, Bonn, Germany
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This preprint is open for discussion and under review for Natural Hazards and Earth System Sciences (NHESS).
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The extreme events heatwaves, droughts, heavy precipitation, floods and wind storms affect socio-economic systems and generate strong public attention. They are embedded into atmospheric dynamics and are statistically rare events. Here we compile the contributions of twenty one articles of the inter-journal NHESS/ASCMO/WCD special issue by project ClimXtreme parallel to results from thirty three more publication. The conclusions underline the complexity of the results.
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The heavy rain over Western Europe in mid July 2021 caused destructive flash floods. Previous research shows that soil moisture played an important role in amplifying the impacts. But how important is soil moisture as a water source for the rain itself? We investigated this question by simulating scenarios with especially wet and dry European soils. We find that soils were integral in supplying water to the event and in strengthening the low pressure system “Bernd” important to the event.
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Europe frequently experiences compound events, with major impacts. We investigate these events’ interactions, characteristics, and changes over time, focusing on socio-economic impacts in Germany and central Europe. Highlighting 2018’s extreme events, this study reveals impacts on water, agriculture, and forests and stresses the need for impact-focused definitions and better future risk quantification to support adaptation planning.
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The extreme events heatwaves, droughts, heavy precipitation, floods and wind storms affect socio-economic systems and generate strong public attention. They are embedded into atmospheric dynamics and are statistically rare events. Here we compile the contributions of twenty one articles of the inter-journal NHESS/ASCMO/WCD special issue by project ClimXtreme parallel to results from thirty three more publication. The conclusions underline the complexity of the results.
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The heavy rain over Western Europe in mid July 2021 caused destructive flash floods. Previous research shows that soil moisture played an important role in amplifying the impacts. But how important is soil moisture as a water source for the rain itself? We investigated this question by simulating scenarios with especially wet and dry European soils. We find that soils were integral in supplying water to the event and in strengthening the low pressure system “Bernd” important to the event.
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Philipp Ertz and Petra Friederichs
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Europe frequently experiences compound events, with major impacts. We investigate these events’ interactions, characteristics, and changes over time, focusing on socio-economic impacts in Germany and central Europe. Highlighting 2018’s extreme events, this study reveals impacts on water, agriculture, and forests and stresses the need for impact-focused definitions and better future risk quantification to support adaptation planning.
Svenja Szemkus and Petra Friederichs
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Short summary
The impact of heavy rainfall is determined not only by the total amount of precipitation, but also by its spatial and temporal characteristics. We develop a statistical framework that extracts key event characteristics, including their time, length and speed from radar-based observations. The results reveal systematic patterns in heavy precipitation events and provide new insights for risk assessment and future climate studies.
The impact of heavy rainfall is determined not only by the total amount of precipitation, but...
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