Articles | Volume 5, issue 4
https://doi.org/10.5194/wcd-5-1457-2024
© 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/wcd-5-1457-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Nov 2024
Research article |
| 12 Nov 2024
| 12 Nov 2024
Dynamic and thermodynamic contribution to the October 2019 exceptional rainfall in western central Africa
Kevin Kenfack
CORRESPONDING AUTHOR
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Department of Physics, University of Yaoundé 1, Yaoundé, Cameroon
Francesco Marra
Department of Geosciences, University of Padua, Padua, Italy
Zéphirin Yepdo Djomou
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Department of Physics, University of Yaoundé 1, Yaoundé, Cameroon
National Institute of Cartography, Yaoundé, Cameroon
Lucie Angennes Djiotang Tchotchou
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Department of Physics, University of Yaoundé 1, Yaoundé, Cameroon
Alain Tchio Tamoffo
Climate Service Center Germany (GERICS), Helmholtz-Zentrum Hereon, Fischertwiete 1, 20095 Hamburg, Germany
Derbetini Appolinaire Vondou
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Department of Physics, University of Yaoundé 1, Yaoundé, Cameroon
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Hermann N. Nana, Masilin Gudoshava, Roméo S. Tanessong, Alain T. Tamoffo, and Derbetini A. Vondou
EGUsphere, https://doi.org/10.5194/egusphere-2025-76, https://doi.org/10.5194/egusphere-2025-76, 2025
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The results of this study show that November 2023 extreme rainfall were controlled by several factors, including strong sea surface temperature anomalies in Niño-3.4, North Tropical Atlantic, Equatorial Atlantic and Indian ocean dipole regions, changes in zonal winds, the Walker circulation, the moisture flux and its divergence, and the easterly jets. The information we derive can be used to support risk assessment in the region and to improve our resilience to ongoing climate change.
Talia Rosin, Francesco Marra, and Efrat Morin
Hydrol. Earth Syst. Sci., 28, 3549–3566, https://doi.org/10.5194/hess-28-3549-2024, https://doi.org/10.5194/hess-28-3549-2024, 2024
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Knowledge of extreme precipitation probability at various spatial–temporal scales is crucial. We estimate extreme precipitation return levels at multiple scales (10 min–24 h, 0.25–500 km2) in the eastern Mediterranean using radar data. We show our estimates are comparable to those derived from averaged daily rain gauges. We then explore multi-scale extreme precipitation across coastal, mountainous, and desert regions.
Rajani Kumar Pradhan, Yannis Markonis, Francesco Marra, Efthymios I. Nikolopoulos, Simon Michael Papalexiou, and Vincenzo Levizzani
EGUsphere, https://doi.org/10.5194/egusphere-2024-1626, https://doi.org/10.5194/egusphere-2024-1626, 2024
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This study compared global satellite and one reanalysis precipitation dataset to assess diurnal variability. We found that all datasets capture key diurnal precipitation patterns, with maximum precipitation in the afternoon over land and early morning over the ocean. However, there are differences in the exact timing and amount of precipitation. This suggests that it is better to use a combination of datasets for potential applications rather than relying on a single dataset.
Francesco Marra, Marika Koukoula, Antonio Canale, and Nadav Peleg
Hydrol. Earth Syst. Sci., 28, 375–389, https://doi.org/10.5194/hess-28-375-2024, https://doi.org/10.5194/hess-28-375-2024, 2024
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We present a new physical-based method for estimating extreme sub-hourly precipitation return levels (i.e., intensity–duration–frequency, IDF, curves), which are critical for the estimation of future floods. The proposed model, named TENAX, incorporates temperature as a covariate in a physically consistent manner. It has only a few parameters and can be easily set for any climate station given sub-hourly precipitation and temperature data are available.
Stefan Steger, Mateo Moreno, Alice Crespi, Peter James Zellner, Stefano Luigi Gariano, Maria Teresa Brunetti, Massimo Melillo, Silvia Peruccacci, Francesco Marra, Robin Kohrs, Jason Goetz, Volkmar Mair, and Massimiliano Pittore
Nat. Hazards Earth Syst. Sci., 23, 1483–1506, https://doi.org/10.5194/nhess-23-1483-2023, https://doi.org/10.5194/nhess-23-1483-2023, 2023
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We present a novel data-driven modelling approach to determine season-specific critical precipitation conditions for landslide occurrence. It is shown that the amount of precipitation required to trigger a landslide in South Tyrol varies from season to season. In summer, a higher amount of preparatory precipitation is required to trigger a landslide, probably due to denser vegetation and higher temperatures. We derive dynamic thresholds that directly relate to hit rates and false-alarm rates.
Nadav Peleg, Herminia Torelló-Sentelles, Grégoire Mariéthoz, Lionel Benoit, João P. Leitão, and Francesco Marra
Nat. Hazards Earth Syst. Sci., 23, 1233–1240, https://doi.org/10.5194/nhess-23-1233-2023, https://doi.org/10.5194/nhess-23-1233-2023, 2023
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Floods in urban areas are one of the most common natural hazards. Due to climate change enhancing extreme rainfall and cities becoming larger and denser, the impacts of these events are expected to increase. A fast and reliable flood warning system should thus be implemented in flood-prone cities to warn the public of upcoming floods. The purpose of this brief communication is to discuss the potential implementation of low-cost acoustic rainfall sensors in short-term flood warning systems.
Eleonora Dallan, Francesco Marra, Giorgia Fosser, Marco Marani, Giuseppe Formetta, Christoph Schär, and Marco Borga
Hydrol. Earth Syst. Sci., 27, 1133–1149, https://doi.org/10.5194/hess-27-1133-2023, https://doi.org/10.5194/hess-27-1133-2023, 2023
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Convection-permitting climate models could represent future changes in extreme short-duration precipitation, which is critical for risk management. We use a non-asymptotic statistical method to estimate extremes from 10 years of simulations in an orographically complex area. Despite overall good agreement with rain gauges, the observed decrease of hourly extremes with elevation is not fully represented by the model. Climate model adjustment methods should consider the role of orography.
Shalev Siman-Tov and Francesco Marra
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
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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.
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.
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.
Yair Rinat, Francesco Marra, Moshe Armon, Asher Metzger, Yoav Levi, Pavel Khain, Elyakom Vadislavsky, Marcelo Rosensaft, and Efrat Morin
Nat. Hazards Earth Syst. Sci., 21, 917–939, https://doi.org/10.5194/nhess-21-917-2021, https://doi.org/10.5194/nhess-21-917-2021, 2021
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Flash floods are among the most devastating and lethal natural hazards worldwide. The study of such events is important as flash floods are poorly understood and documented processes, especially in deserts. A small portion of the studied basin (1 %–20 %) experienced extreme rainfall intensities resulting in local flash floods of high magnitudes. Flash floods started and reached their peak within tens of minutes. Forecasts poorly predicted the flash floods mostly due to location inaccuracy.
Moshe Armon, Francesco Marra, Yehouda Enzel, Dorita Rostkier-Edelstein, and Efrat Morin
Hydrol. Earth Syst. Sci., 24, 1227–1249, https://doi.org/10.5194/hess-24-1227-2020, https://doi.org/10.5194/hess-24-1227-2020, 2020
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Heavy precipitation events (HPEs), occurring around the globe, lead to natural hazards as well as to water resource recharge. Rainfall patterns during HPEs vary from one case to another and govern their effect. Thus, correct prediction of these patterns is crucial for coping with HPEs. However, the ability of weather models to generate such patterns is unclear. Here, we characterise rainfall patterns during HPEs based on weather radar data and evaluate weather model simulations of these events.
Davide Zoccatelli, Francesco Marra, Moshe Armon, Yair Rinat, James A. Smith, and Efrat Morin
Hydrol. Earth Syst. Sci., 23, 2665–2678, https://doi.org/10.5194/hess-23-2665-2019, https://doi.org/10.5194/hess-23-2665-2019, 2019
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This study presents a comparison of flood properties over multiple Mediterranean and desert catchments. While in Mediterranean areas floods are related to rainfall amount, in deserts we observed a strong connection with the characteristics of the more intense part of storms. Because of the different mechanisms involved, despite having significantly shorter and more localized storms, deserts are able to produce floods with a magnitude comparable to Mediterranean areas.
William Amponsah, Pierre-Alain Ayral, Brice Boudevillain, Christophe Bouvier, Isabelle Braud, Pascal Brunet, Guy Delrieu, Jean-François Didon-Lescot, Eric Gaume, Laurent Lebouc, Lorenzo Marchi, Francesco Marra, Efrat Morin, Guillaume Nord, Olivier Payrastre, Davide Zoccatelli, and Marco Borga
Earth Syst. Sci. Data, 10, 1783–1794, https://doi.org/10.5194/essd-10-1783-2018, https://doi.org/10.5194/essd-10-1783-2018, 2018
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The EuroMedeFF database comprises 49 events that occurred in France, Israel, Germany, Slovenia, Romania, and Italy. The dataset may be of help to hydrologists as well as other scientific communities because it offers benchmark data for the verification of flash flood hydrological models and for hydro-meteorological forecast systems. It provides, moreover, a sample of rainfall and flood discharge extremes in different climates.
Idit Belachsen, Francesco Marra, Nadav Peleg, and Efrat Morin
Hydrol. Earth Syst. Sci., 21, 5165–5180, https://doi.org/10.5194/hess-21-5165-2017, https://doi.org/10.5194/hess-21-5165-2017, 2017
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Spatiotemporal rainfall patterns in arid environments are not well-known. We derived properties of convective rain cells over the arid Dead Sea region from a long-term radar archive. We found differences in cell properties between synoptic systems and between flash-flood and non-flash-flood events. Large flash floods are associated with slow rain cells, directed downstream with the main catchment axis. Results from this work can be used for hydrological models and stochastic storm simulations.
Francesco Marra, Elisa Destro, Efthymios I. Nikolopoulos, Davide Zoccatelli, Jean Dominique Creutin, Fausto Guzzetti, and Marco Borga
Hydrol. Earth Syst. Sci., 21, 4525–4532, https://doi.org/10.5194/hess-21-4525-2017, https://doi.org/10.5194/hess-21-4525-2017, 2017
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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.
Francesco Marra, Efrat Morin, Nadav Peleg, Yiwen Mei, and Emmanouil N. Anagnostou
Hydrol. Earth Syst. Sci., 21, 2389–2404, https://doi.org/10.5194/hess-21-2389-2017, https://doi.org/10.5194/hess-21-2389-2017, 2017
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Rainfall frequency analyses from radar and satellite estimates over the eastern Mediterranean are compared examining different climatic conditions. Correlation between radar and satellite results is high for frequent events and decreases with return period. The uncertainty related to record length is larger for drier climates. The agreement between different sensors instills confidence on their use for rainfall frequency analysis in ungauged areas of the Earth.
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Links between the atmospheric water cycle and weather systems
A climatological characterization of North Atlantic winter jet streaks and their extremes
Revisiting the moisture budget of the Mediterranean region in the ERA5 reanalysis
Diverse Causes of Extreme Rainfall in November 2023 over Equatorial Africa
Extreme Mediterranean cyclones and associated variables in an atmosphere-only vs an ocean-coupled regional model
Influence of mid-latitude sea surface temperature fronts on the atmospheric water cycle and storm track activity
Impact of precipitation mass sinks on midlatitude storms in idealized simulations across a wide range of climates
The monthly evolution of precipitation and warm conveyor belts during the central southwest Asia wet season
Exploring hail and lightning diagnostics over the Alpine-Adriatic region in a km-scale climate model
Model-simulated hydroclimate in the East Asian summer monsoon region during past and future climate: a pilot study with a moisture source perspective
Lagrangian formation pathways of moist anomalies in the trade-wind region during the dry season: two case studies from EUREC4A
A numerical study to investigate the roles of former Hurricane Leslie, orography and evaporative cooling in the 2018 Aude heavy-precipitation event
High-resolution stable isotope signature of a land-falling atmospheric river in southern Norway
Atmospheric convergence zones stemming from large-scale mixing
The role of air–sea fluxes for the water vapour isotope signals in the cold and warm sectors of extratropical cyclones over the Southern Ocean
Extreme wet seasons – their definition and relationship with synoptic-scale weather systems
Attribution of precipitation to cyclones and fronts over Europe in a kilometer-scale regional climate simulation
An attempt to explain recent changes in European snowfall extremes
Mona Bukenberger, Lena Fasnacht, Stefan Rüdisühli, and Sebastian Schemm
Weather Clim. Dynam., 6, 279–316, https://doi.org/10.5194/wcd-6-279-2025, https://doi.org/10.5194/wcd-6-279-2025, 2025
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The jet stream is a band of strong westerly winds, within which jet streaks are regions of faster wind speeds that can aid storm development. This study analyses jet streaks over the North Atlantic during winter. Jet streaks are linked to pairs of surface anticyclones and cyclones and are often accompanied by intense precipitation, especially extreme jet streaks. With cloud processes playing an increased role in extreme jet streaks, follow-up studies concerning their role are warranted.
Roshanak Tootoonchi, Simona Bordoni, and Roberta D'Agostino
Weather Clim. Dynam., 6, 245–263, https://doi.org/10.5194/wcd-6-245-2025, https://doi.org/10.5194/wcd-6-245-2025, 2025
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In this study, we explore the role of stationary circulations arising from deviations from the zonal mean in the distinct transition from net evaporation over the ocean to net precipitation over land in the Mediterranean region from ERA5. Stationary eddies reinforce the wetting tendency over land and oppose the drying tendency over the ocean due to transient storms. Our results have important implications for future changes in the region, previously identified as a climate change hot spot.
Hermann N. Nana, Masilin Gudoshava, Roméo S. Tanessong, Alain T. Tamoffo, and Derbetini A. Vondou
EGUsphere, https://doi.org/10.5194/egusphere-2025-76, https://doi.org/10.5194/egusphere-2025-76, 2025
Short summary
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The results of this study show that November 2023 extreme rainfall were controlled by several factors, including strong sea surface temperature anomalies in Niño-3.4, North Tropical Atlantic, Equatorial Atlantic and Indian ocean dipole regions, changes in zonal winds, the Walker circulation, the moisture flux and its divergence, and the easterly jets. The information we derive can be used to support risk assessment in the region and to improve our resilience to ongoing climate change.
Marco Chericoni, Giorgia Fosser, Emmanouil Flaounas, Gianmaria Sannino, and Alessandro Anav
EGUsphere, https://doi.org/10.5194/egusphere-2024-2829, https://doi.org/10.5194/egusphere-2024-2829, 2024
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This study explores how sea surface energy influences both the atmosphere and ocean at various vertical levels during extreme Mediterranean cyclones. It focuses on cyclones' precipitation and wind speed response, as well as on ocean temperature variation. The analysis shows the effectiveness of the Regional Coupled Model in coherently representing the thermodynamic processes associated with extreme cyclones across both the atmosphere and the ocean.
Fumiaki Ogawa and Thomas Spengler
Weather Clim. Dynam., 5, 1031–1042, https://doi.org/10.5194/wcd-5-1031-2024, https://doi.org/10.5194/wcd-5-1031-2024, 2024
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The exchange of energy and moisture between the atmosphere and ocean is maximised along strong meridional contrasts in sea surface temperature, such as across the Gulf Stream and Kuroshio. We find that these strong meridional contrasts confine and determine the position of evaporation and precipitation, as well as storm occurrence and intensity. The general intensity of the water cycle and storm activity, however, is determined by the underlying absolute sea surface temperature.
Tristan H. Abbott and Paul A. O'Gorman
Weather Clim. Dynam., 5, 17–41, https://doi.org/10.5194/wcd-5-17-2024, https://doi.org/10.5194/wcd-5-17-2024, 2024
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Atmospheric models often neglect the mass sink from precipitation fallout, but a small number of modeling studies suggest that this mass sink may intensify storms. We provide evidence, using simulations and theory, that precipitation mass sinks have little systematic effect on storm intensity unless exaggerated by an order of magnitude. This result holds even in very warm climates with very heavy rainfall and helps to justify the neglect of precipitation mass sinks in atmospheric models.
Melissa Leah Breeden, Andrew Hoell, John Robert Albers, and Kimberly Slinski
Weather Clim. Dynam., 4, 963–980, https://doi.org/10.5194/wcd-4-963-2023, https://doi.org/10.5194/wcd-4-963-2023, 2023
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We compare the month-to-month evolution of daily precipitation over central southwest Asia (CSWA), a data-sparse, food-insecure area prone to drought and flooding. The seasonality of CSWA precipitation aligns with the seasonality of warm conveyor belts (WCBs), the warm, rapidly ascending airstreams associated with extratropical storms, most common from February–April. El Niño conditions are related to more WCBs and precipitation and La Niña conditions the opposite, except in January.
Ruoyi Cui, Nikolina Ban, Marie-Estelle Demory, Raffael Aellig, Oliver Fuhrer, Jonas Jucker, Xavier Lapillonne, and Christoph Schär
Weather Clim. Dynam., 4, 905–926, https://doi.org/10.5194/wcd-4-905-2023, https://doi.org/10.5194/wcd-4-905-2023, 2023
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Our study focuses on severe convective storms that occur over the Alpine-Adriatic region. By running simulations for eight real cases and evaluating them against available observations, we found our models did a good job of simulating total precipitation, hail, and lightning. Overall, this research identified important meteorological factors for hail and lightning, and the results indicate that both HAILCAST and LPI diagnostics are promising candidates for future climate research.
Astrid Fremme, Paul J. Hezel, Øyvind Seland, and Harald Sodemann
Weather Clim. Dynam., 4, 449–470, https://doi.org/10.5194/wcd-4-449-2023, https://doi.org/10.5194/wcd-4-449-2023, 2023
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We study the atmospheric moisture transport into eastern China for past, present, and future climate. Hence, we use different climate and weather prediction model data with a moisture source identification method. We find that while the moisture to first order originates mostly from similar regions, smaller changes consistently point to differences in the recycling of precipitation over land between different climates. Some differences are larger between models than between different climates.
Leonie Villiger, Heini Wernli, Maxi Boettcher, Martin Hagen, and Franziska Aemisegger
Weather Clim. Dynam., 3, 59–88, https://doi.org/10.5194/wcd-3-59-2022, https://doi.org/10.5194/wcd-3-59-2022, 2022
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The coupling between the large-scale atmospheric circulation and the clouds in the trade-wind region is complex and not yet fully understood. In this study, the formation pathway of two anomalous cloud layers over Barbados during the field campaign EUREC4A is described. The two case studies highlight the influence of remote weather systems on the local environmental conditions in Barbados.
Marc Mandement and Olivier Caumont
Weather Clim. Dynam., 2, 795–818, https://doi.org/10.5194/wcd-2-795-2021, https://doi.org/10.5194/wcd-2-795-2021, 2021
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On 14–15 October 2018, in the Aude department (France), a heavy-precipitation event produced up to about 300 mm of rain in 11 h. Simulations carried out show that the former Hurricane Leslie, while involved, was not the first supplier of moisture over the entire event. The location of the highest rainfall was primarily driven by the location of a quasi-stationary front and secondarily by the location of precipitation bands downwind of mountains bordering the Mediterranean Sea.
Yongbiao Weng, Aina Johannessen, and Harald Sodemann
Weather Clim. Dynam., 2, 713–737, https://doi.org/10.5194/wcd-2-713-2021, https://doi.org/10.5194/wcd-2-713-2021, 2021
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High-resolution measurements of stable isotopes in near-surface vapour and precipitation show a
W-shaped evolution during a 24 h land-falling atmospheric river event in southern Norway. We distinguish contributions from below-cloud processes, weather system characteristics, and moisture source conditions during different stages of the event. Rayleigh distillation models need to be expanded by additional processes to accurately predict isotopes in surface precipitation from stratiform clouds.
Gabriel M. P. Perez, Pier Luigi Vidale, Nicholas P. Klingaman, and Thomas C. M. Martin
Weather Clim. Dynam., 2, 475–488, https://doi.org/10.5194/wcd-2-475-2021, https://doi.org/10.5194/wcd-2-475-2021, 2021
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Much of the rainfall in tropical regions comes from organised cloud bands called convergence zones (CZs). These bands have hundreds of kilometers. In South America (SA), they cause intense rain for long periods of time. To study these systems, we need to define and identify them with computer code. We propose a definition of CZs based on the the pathways of air, selecting regions where air masses originated in separated regions meet. This method identifies important mechanisms of rain in SA.
Iris Thurnherr, Katharina Hartmuth, Lukas Jansing, Josué Gehring, Maxi Boettcher, Irina Gorodetskaya, Martin Werner, Heini Wernli, and Franziska Aemisegger
Weather Clim. Dynam., 2, 331–357, https://doi.org/10.5194/wcd-2-331-2021, https://doi.org/10.5194/wcd-2-331-2021, 2021
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Extratropical cyclones are important for the transport of moisture from low to high latitudes. In this study, we investigate how the isotopic composition of water vapour is affected by horizontal temperature advection associated with extratropical cyclones using measurements and modelling. It is shown that air–sea moisture fluxes induced by this horizontal temperature advection lead to the strong variability observed in the isotopic composition of water vapour in the marine boundary layer.
Emmanouil Flaounas, Matthias Röthlisberger, Maxi Boettcher, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 2, 71–88, https://doi.org/10.5194/wcd-2-71-2021, https://doi.org/10.5194/wcd-2-71-2021, 2021
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In this study we identify the wettest seasons globally and address their meteorological characteristics. We show that in different regions the wettest seasons occur in different times of the year and result from either unusually high frequencies of wet days and/or daily extremes. These high frequencies can be largely attributed to four specific weather systems, especially cyclones. Our analysis uses a thoroughly explained, novel methodology that could also be applied to climate models.
Stefan Rüdisühli, Michael Sprenger, David Leutwyler, Christoph Schär, and Heini Wernli
Weather Clim. Dynam., 1, 675–699, https://doi.org/10.5194/wcd-1-675-2020, https://doi.org/10.5194/wcd-1-675-2020, 2020
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Most precipitation over Europe is linked to low-pressure systems, cold fronts, warm fronts, or high-pressure systems. Based on a massive computer simulation able to resolve thunderstorms, we quantify in detail how much precipitation these weather systems produced during 2000–2008. We find distinct seasonal and regional differences, such as fronts precipitating a lot in fall and winter over the North Atlantic but high-pressure systems mostly in summer over the continent by way of thunderstorms.
Davide Faranda
Weather Clim. Dynam., 1, 445–458, https://doi.org/10.5194/wcd-1-445-2020, https://doi.org/10.5194/wcd-1-445-2020, 2020
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Despite the global temperature rise caused by anthropogenic emissions, we still observe heavy snowfalls that cause casualties, transport disruptions and energy supply problems. The goal of this paper is to investigate recent trends in snowfalls from reanalysis and observational datasets. The analysis shows an evident discrepancy between trends in average and extreme snowfalls. The latter can only be explained by looking at atmospheric circulation.
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Short summary
The results of this study show that moisture advection induced by horizontal wind anomalies and vertical moisture advection induced by vertical velocity anomalies were crucial mechanisms behind the anomalous October 2019 exceptional rainfall increase over western central Africa. The information we derive can be used to support risk assessment and management in the region and to improve our resilience to ongoing climate change.
The results of this study show that moisture advection induced by horizontal wind anomalies and...
