Articles | Volume 21, issue 9
https://doi.org/10.5194/hess-21-4525-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/hess-21-4525-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Impact of rainfall spatial aggregation on the identification of debris flow occurrence thresholds
Francesco Marra
CORRESPONDING AUTHOR
Institute of Earth Sciences, Hebrew University of Jerusalem, 91904, Jerusalem, Israel
Elisa Destro
Department of Land, Environment, Agriculture and Forestry, University of Padova, Padua, Italy
Efthymios I. Nikolopoulos
Department of Civil and Environmental Engineering, University of Connecticut, Storrs, CT, USA
Davide Zoccatelli
Institute of Earth Sciences, Hebrew University of Jerusalem, 91904, Jerusalem, Israel
Department of Land, Environment, Agriculture and Forestry, University of Padova, Padua, Italy
Jean Dominique Creutin
Institut des Géosciences pour l'Environnement, Université de Grenoble Alpes/CNRS, Grenoble, France
Fausto Guzzetti
Istituto di Ricerca per la Protezione Idrogeologica, Consiglio Nazionale delle Ricerche, Perugia, Italy
Marco Borga
Department of Land, Environment, Agriculture and Forestry, University of Padova, Padua, Italy
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Francesco Marra, Eleonora Dallan, Marco Borga, Roberto Greco, and Thom Bogaard
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Short summary
Short summary
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Short summary
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Nat. Hazards Earth Syst. Sci., 23, 1079–1093, https://doi.org/10.5194/nhess-23-1079-2023, https://doi.org/10.5194/nhess-23-1079-2023, 2023
Short summary
Short summary
Debris flows represent a threat to infrastructure and the population. In arid areas, they are observed when heavy rainfall hits steep slopes with sediments. Here, we use digital surface models and radar rainfall data to detect and characterize the triggering and non-triggering rainfall conditions. We find that rainfall intensity alone is insufficient to explain the triggering. We suggest that antecedent rainfall could represent a critical factor for debris flow triggering in arid regions.
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Manuscript not accepted for further review
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We analyzed the variability in the isotopic composition of plant water extracted by two different methods, i.e., cryogenic vacuum distillation (CVD) and Scholander-type pressure chamber (SPC). Our results indicated that the isotopic composition of plant water extracted by CVD and SPC was significantly different. We concluded that plant water extraction by SPC is not an alternative for CVD as SPC mostly extracts the mobile plant water whereas CVD retrieves all water stored in the sampled tissue.
Assaf Hochman, Francesco Marra, Gabriele Messori, Joaquim G. Pinto, Shira Raveh-Rubin, Yizhak Yosef, and Georgios Zittis
Earth Syst. Dynam., 13, 749–777, https://doi.org/10.5194/esd-13-749-2022, https://doi.org/10.5194/esd-13-749-2022, 2022
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Gaining a complete understanding of extreme weather, from its physical drivers to its impacts on society, is important in supporting future risk reduction and adaptation measures. Here, we provide a review of the available scientific literature, knowledge gaps and key open questions in the study of extreme weather events over the vulnerable eastern Mediterranean region.
Francesco Marra, Moshe Armon, and Efrat Morin
Hydrol. Earth Syst. Sci., 26, 1439–1458, https://doi.org/10.5194/hess-26-1439-2022, https://doi.org/10.5194/hess-26-1439-2022, 2022
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We present a new method for quantifying the probability of occurrence of extreme rainfall using radar data, and we use it to examine coastal and orographic effects on extremes. We identify three regimes, directly related to precipitation physical processes, which respond differently to these forcings. The methods and results are of interest for researchers and practitioners using radar for the analysis of extremes, risk managers, water resources managers, and climate change impact studies.
Antoine Blanc, Juliette Blanchet, and Jean-Dominique Creutin
Weather Clim. Dynam., 3, 231–250, https://doi.org/10.5194/wcd-3-231-2022, https://doi.org/10.5194/wcd-3-231-2022, 2022
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Precipitation variability and extremes in the northern French Alps are governed by the atmospheric circulation over western Europe. In this work, we study the past evolution of western Europe large-scale circulation using atmospheric descriptors. We show some discrepancies in the trends obtained from different reanalyses before 1950. After 1950, we find trends in Mediterranean circulations that appear to be linked with trends in seasonal and extreme precipitation in the northern French Alps.
Yoav Ben Dor, Francesco Marra, Moshe Armon, Yehouda Enzel, Achim Brauer, Markus Julius Schwab, and Efrat Morin
Clim. Past, 17, 2653–2677, https://doi.org/10.5194/cp-17-2653-2021, https://doi.org/10.5194/cp-17-2653-2021, 2021
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Laminated sediments from the deepest part of the Dead Sea unravel the hydrological response of the eastern Mediterranean to past climate changes. This study demonstrates the importance of geological archives in complementing modern hydrological measurements that do not fully capture natural hydroclimatic variability, which is crucial to configure for understanding the impact of climate change on the hydrological cycle in subtropical regions.
Elena Mondino, Anna Scolobig, Marco Borga, and Giuliano Di Baldassarre
Nat. Hazards Earth Syst. Sci., 21, 2811–2828, https://doi.org/10.5194/nhess-21-2811-2021, https://doi.org/10.5194/nhess-21-2811-2021, 2021
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Survey data collected over time can provide new insights on how different people respond to floods and can be used in models to study the complex coevolution of human–water systems. We present two methods to collect such data, and we compare the respective results. Risk awareness decreases only for women, while preparedness takes different trajectories depending on the damage suffered. These results support a more diverse representation of society in flood risk modelling and risk management.
Cited articles
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Short summary
Previous studies have reported a systematic underestimation of debris flow occurrence thresholds, due to the use of sparse networks in non-stationary rain fields. We analysed high-resolution radar data to show that spatially aggregated estimates (e.g. satellite data) largely reduce this issue, in light of a reduced estimation variance. Our findings are transferable to other situations in which lower envelope curves are used to predict point-like events in the presence of non-stationary fields.
Previous studies have reported a systematic underestimation of debris flow occurrence...