Articles | Volume 11, issue 4
https://doi.org/10.5194/esurf-11-803-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-11-803-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Aug 2023
Research article |
| 15 Aug 2023
| 15 Aug 2023
The probabilistic nature of dune collisions in 2D
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, UK
Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205 Geneva, Switzerland
GNS Science, 1 Fairway Drive, 5011 Lower Hutt, New Zealand
Clement Narteau
Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, 1 Rue Jussieu, 75005 Paris, France
Olivier Rozier
Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, 1 Rue Jussieu, 75005 Paris, France
Nathalie M. Vriend
BP Institute, University of Cambridge, Madingley Road, Cambridge, CB3 0EZ, UK
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, UK
Department of Earth Sciences, University of Cambridge, Madingley Road, Cambridge, CB3 0EZ, UK
College of Engineering and Applied Science, University of Colorado Boulder, 1111 Engineering Drive, Boulder, Colorado, USA
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Jean Vérité, Clément Narteau, Olivier Rozier, Jeanne Alkalla, Laurie Barrier, and Sylvain Courrech du Pont
Earth Surf. Dynam., 13, 23–39, https://doi.org/10.5194/esurf-13-23-2025, https://doi.org/10.5194/esurf-13-23-2025, 2025
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Using a numerical model in 2D, we study how two identical dunes interact with each other when exposed to reversing winds. Depending on the distance between the dunes, they either repel or attract each other until they reach an equilibrium distance, which is controlled by the wind strength, wind reversal frequency, and dune size. This process is controlled by the modification of wind flow over dunes of various shapes, influencing the sediment transport downstream.
Laure Guerit, Laurie Barrier, Youcun Liu, Clément Narteau, Eric Lajeunesse, Eric Gayer, and François Métivier
Earth Surf. Dynam., 6, 1011–1021, https://doi.org/10.5194/esurf-6-1011-2018, https://doi.org/10.5194/esurf-6-1011-2018, 2018
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The grain-size distribution of ancient alluvial systems is commonly determined from sections of gravel deposits exposed vertically to reconstruct paleo-environments or changes in tectonics and/or climate. To test whether such a grain-size distribution is equivalent to one of the sediments that was in direct contact with the flow at the time of deposition, we dug a large trench in an active gravel-bedded, braided river. We show that the granulometry is uniform at the scale of the active layer.
Related subject area
Physical: Geomorphology (including all aspects of fluvial, coastal, aeolian, hillslope and glacial geomorphology)
Equilibrium distance from long-range dune interactions
Examination of analytical shear stress predictions for coastal dune evolution
Post-fire evolution of ravel transport regimes in the Diablo Range, CA
Landscape response to tectonic deformation and cyclic climate change since ca. 800 ka in the southern central Andes
The Aare main overdeepening on the northern margin of the European Alps: basins, riegels, and slot canyons
A simple model for faceted topographies at normal faults based on an extended stream-power law
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River suspended-sand flux computation with uncertainty estimation using water samples and high-resolution ADCP measurements
Barchan swarm dynamics from a Two-Flank Agent-Based Model
A landslide runout model for sediment transport, landscape evolution, and hazard assessment applications
Tracking slow-moving landslides with PlanetScope data: new perspectives on the satellite's perspective
Topographic metrics for unveiling fault segmentation and tectono-geomorphic evolution with insights into the impact of inherited topography, Ulsan Fault Zone, South Korea
Acceleration of coastal-retreat rates for high-Arctic rock cliffs on Brøggerhalvøya, Svalbard, over the past decade
The impact of bedrock meander cutoffs on 50 kyr scale incision rates, San Juan River, Utah
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Terrace formation linked to outburst floods at the Diexi palaeo-landslide dam, upper Minjiang River, eastern Tibetan Plateau
Width evolution of channel belts as a random walk
Pliocene shorelines and the epeirogenic motion of continental margins: a target dataset for dynamic topography models
Decadal-scale decay of landslide-derived fluvial suspended sediment after Typhoon Morakot
Role of the forcing sources in morphodynamic modelling of an embayed beach
Geomorphic imprint of high mountain floods: Insight from the 2022 hydrological extreme across the Upper Indus terrain in NW Himalayas
A machine learning approach to the geomorphometric detection of ribbed moraines in Norway
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Implications for the resilience of modern coastal systems derived from mesoscale barrier dynamics at Fire Island, New York
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Jean Vérité, Clément Narteau, Olivier Rozier, Jeanne Alkalla, Laurie Barrier, and Sylvain Courrech du Pont
Earth Surf. Dynam., 13, 23–39, https://doi.org/10.5194/esurf-13-23-2025, https://doi.org/10.5194/esurf-13-23-2025, 2025
Short summary
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Using a numerical model in 2D, we study how two identical dunes interact with each other when exposed to reversing winds. Depending on the distance between the dunes, they either repel or attract each other until they reach an equilibrium distance, which is controlled by the wind strength, wind reversal frequency, and dune size. This process is controlled by the modification of wind flow over dunes of various shapes, influencing the sediment transport downstream.
Orie Cecil, Nicholas Cohn, Matthew Farthing, Sourav Dutta, and Andrew Trautz
Earth Surf. Dynam., 13, 1–22, https://doi.org/10.5194/esurf-13-1-2025, https://doi.org/10.5194/esurf-13-1-2025, 2025
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Using computational fluid dynamics, we analyze the error trends of an analytical shear stress distribution model used to drive aeolian transport for coastal dunes, which are an important line of defense against storm-related flooding hazards. We find that compared to numerical simulations, the analytical model results in a net overprediction of the landward migration rate. Additionally, two data-driven approaches are proposed for reducing the error while maintaining computational efficiency.
Hayden L. Jacobson, Danica L. Roth, Gabriel Walton, Margaret Zimmer, and Kerri Johnson
Earth Surf. Dynam., 12, 1415–1446, https://doi.org/10.5194/esurf-12-1415-2024, https://doi.org/10.5194/esurf-12-1415-2024, 2024
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Loose grains travel farther after a fire because no vegetation is left to stop them. This matters since loose grains at the base of a slope can turn into a debris flow if it rains. To find if grass growing back after a fire had different impacts on grains of different sizes on slopes of different steepness, we dropped thousands of natural grains and measured how far they went. Large grains went farther 7 months after the fire than 11 months after, and small grain movement didn’t change much.
Elizabeth N. Orr, Taylor F. Schildgen, Stefanie Tofelde, Hella Wittmann, and Ricardo N. Alonso
Earth Surf. Dynam., 12, 1391–1413, https://doi.org/10.5194/esurf-12-1391-2024, https://doi.org/10.5194/esurf-12-1391-2024, 2024
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Fluvial terraces and alluvial fans in the Toro Basin, NW Argentina, record river evolution and global climate cycles over time. Landform dating reveals lower-frequency climate cycles (100 kyr) preserved downstream and higher-frequency cycles (21/40 kyr) upstream, supporting theoretical predications that longer rivers filter out higher-frequency climate signals. This finding improves our understanding of the spatial distribution of sedimentary paleoclimate records within landscapes.
Fritz Schlunegger, Edi Kissling, Dimitri Tibo Bandou, Guilhem Amin Douillet, David Mair, Urs Marti, Regina Reber, Patrick Schläfli, and Michael Alfred Schwenk
Earth Surf. Dynam., 12, 1371–1389, https://doi.org/10.5194/esurf-12-1371-2024, https://doi.org/10.5194/esurf-12-1371-2024, 2024
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Overdeepenings are bedrock depressions filled with sediment. We combine the results of a gravity survey with drilling data to explore the morphology of such a depression beneath the city of Bern. We find that the target overdeepening comprises two basins >200 m deep. They are separated by a bedrock riegel that itself is cut by narrow canyons up to 150 m deep. We postulate that these structures formed underneath a glacier, where erosion by subglacial meltwater caused the formation of the canyons.
Stefan Hergarten
Earth Surf. Dynam., 12, 1315–1327, https://doi.org/10.5194/esurf-12-1315-2024, https://doi.org/10.5194/esurf-12-1315-2024, 2024
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Faceted topographies are impressive footprints of active tectonics in geomorphology. This paper investigates the evolution of faceted topographies at normal faults and their interaction with a river network theoretically and numerically. As a main result beyond several relations for the geometry of facets, the horizontal displacement associated with normal faults is crucial for the dissection of initially polygonal facets into triangular facets bounded by almost parallel rivers.
Justin A. Nghiem, Gen K. Li, Joshua P. Harringmeyer, Gerard Salter, Cédric G. Fichot, Luca Cortese, and Michael P. Lamb
Earth Surf. Dynam., 12, 1267–1294, https://doi.org/10.5194/esurf-12-1267-2024, https://doi.org/10.5194/esurf-12-1267-2024, 2024
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Fine sediment grains in freshwater can cohere into faster-settling particles called flocs, but floc settling velocity theory has not been fully validated. Combining three data sources in novel ways in the Wax Lake Delta, we verified a semi-empirical model relying on turbulence and geochemical factors. For a physics-based model, we showed that the representative grain diameter within flocs relies on floc structure and that heterogeneous flow paths inside flocs increase floc settling velocity.
Jessica Marggraf, Guillaume Dramais, Jérôme Le Coz, Blaise Calmel, Benoît Camenen, David J. Topping, William Santini, Gilles Pierrefeu, and François Lauters
Earth Surf. Dynam., 12, 1243–1266, https://doi.org/10.5194/esurf-12-1243-2024, https://doi.org/10.5194/esurf-12-1243-2024, 2024
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Suspended-sand fluxes in rivers vary with time and space, complicating their measurement. The proposed method captures the vertical and lateral variations of suspended-sand concentration throughout a river cross-section. It merges water samples taken at various positions throughout the cross-section with high-resolution acoustic velocity measurements. This is the first method that includes a fully applicable uncertainty estimation; it can easily be applied to any other study sites.
Dominic T. Robson and Andreas C. W. Baas
Earth Surf. Dynam., 12, 1205–1226, https://doi.org/10.5194/esurf-12-1205-2024, https://doi.org/10.5194/esurf-12-1205-2024, 2024
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Barchans are fast-moving sand dunes which form large populations (swarms) on Earth and Mars. We show that a small range of model parameters produces swarms in which dune size does not vary downwind – something that is observed in nature but not when using earlier models. We also show how the shape of dunes and the spatial patterns they form are affected by wind direction. This work furthers our understanding of the interplay between environmental drivers, dune interactions, and swarm properties.
Jeffrey Keck, Erkan Istanbulluoglu, Benjamin Campforts, Gregory Tucker, and Alexander Horner-Devine
Earth Surf. Dynam., 12, 1165–1191, https://doi.org/10.5194/esurf-12-1165-2024, https://doi.org/10.5194/esurf-12-1165-2024, 2024
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MassWastingRunout (MWR) is a new landslide runout model designed for sediment transport, landscape evolution, and hazard assessment applications. MWR is written in Python and includes a calibration utility that automatically determines best-fit parameters for a site and empirical probability density functions of each parameter for probabilistic model implementation. MWR and Jupyter Notebook tutorials are available as part of the Landlab package at https://github.com/landlab/landlab.
Ariane Mueting and Bodo Bookhagen
Earth Surf. Dynam., 12, 1121–1143, https://doi.org/10.5194/esurf-12-1121-2024, https://doi.org/10.5194/esurf-12-1121-2024, 2024
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This study investigates the use of optical PlanetScope data for offset tracking of the Earth's surface movement. We found that co-registration accuracy is locally degraded when outdated elevation models are used for orthorectification. To mitigate this bias, we propose to only correlate scenes acquired from common perspectives or base orthorectification on more up-to-date elevation models generated from PlanetScope data alone. This enables a more detailed analysis of landslide dynamics.
Cho-Hee Lee, Yeong Bae Seong, John Weber, Sangmin Ha, Dong-Eun Kim, and Byung Yong Yu
Earth Surf. Dynam., 12, 1091–1120, https://doi.org/10.5194/esurf-12-1091-2024, https://doi.org/10.5194/esurf-12-1091-2024, 2024
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Topographic metrics were used to understand changes due to tectonic activity. We evaluated the relative tectonic activity along the Ulsan Fault Zone (UFZ), one of the most active fault zones in South Korea. We divided the UFZ into five segments, based on the spatial variation in activity. We modeled the landscape evolution of the study area and interpreted tectono-geomorphic history during which the northern part of the UFZ experienced asymmetric uplift, while the southern part did not.
Juditha Aga, Livia Piermattei, Luc Girod, Kristoffer Aalstad, Trond Eiken, Andreas Kääb, and Sebastian Westermann
Earth Surf. Dynam., 12, 1049–1070, https://doi.org/10.5194/esurf-12-1049-2024, https://doi.org/10.5194/esurf-12-1049-2024, 2024
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Coastal rock cliffs on Svalbard are considered to be fairly stable; however, long-term trends in coastal-retreat rates remain unknown. This study examines changes in the coastline position along Brøggerhalvøya, Svalbard, using aerial images from 1970, 1990, 2010, and 2021. Our analysis shows that coastal-retreat rates accelerate during the period 2010–2021, which coincides with increasing storminess and retreating sea ice.
Aaron T. Steelquist, Gustav B. Seixas, Mary L. Gillam, Sourav Saha, Seulgi Moon, and George E. Hilley
Earth Surf. Dynam., 12, 1071–1089, https://doi.org/10.5194/esurf-12-1071-2024, https://doi.org/10.5194/esurf-12-1071-2024, 2024
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The rates at which rivers erode their bed can be used to interpret the geologic history of a region. However, these rates depend significantly on the time window over which you measure. We use multiple dating methods to determine an incision rate for the San Juan River and compare it to regional rates with longer timescales. We demonstrate how specific geologic events, such as cutoffs of bedrock meander bends, are likely to preserve material we can date but also bias the rates we measure.
Johannes Leinauer, Michael Dietze, Sibylle Knapp, Riccardo Scandroglio, Maximilian Jokel, and Michael Krautblatter
Earth Surf. Dynam., 12, 1027–1048, https://doi.org/10.5194/esurf-12-1027-2024, https://doi.org/10.5194/esurf-12-1027-2024, 2024
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Massive rock slope failures are a significant alpine hazard and change the Earth's surface. Therefore, we must understand what controls the preparation of such events. By correlating 4 years of slope displacements with meteorological and seismic data, we found that water from rain and snowmelt is the most important driver. Our approach is applicable to similar sites and indicates where future climatic changes, e.g. in rain intensity and frequency, may alter the preparation of slope failure.
Julien Coatléven and Benoit Chauveau
Earth Surf. Dynam., 12, 995–1026, https://doi.org/10.5194/esurf-12-995-2024, https://doi.org/10.5194/esurf-12-995-2024, 2024
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The aim of this paper is to explain how to incorporate classical water flow routines into landscape evolution models while keeping numerical errors under control. The key idea is to adapt filtering strategies to eliminate anomalous numerical errors and mesh dependencies, as confirmed by convergence tests with analytic solutions. The emergence of complex geomorphic structures is now driven exclusively by nonlinear heterogeneous physical processes rather than by random numerical artifacts.
Chloé Seibert, Cecilia McHugh, Chris Paola, Leonardo Seeber, and James Tucker
EGUsphere, https://doi.org/10.5194/egusphere-2024-2011, https://doi.org/10.5194/egusphere-2024-2011, 2024
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We propose a new mechanism of widespread surficial co-seismic sediment entrainment by seismic motions in subduction earthquakes. Our physical experiments show that shear from sediment-water relative velocities from long-period earthquake motions can mobilize synthetic fine marine sediment. High frequency vertical shaking can enhance this mobilization. According to our results, the largest tsunamigenic earthquakes that rupture to the trench may be distinguishable in the sedimentary record.
Jingjuan Li, John D. Jansen, Xuanmei Fan, Zhiyong Ding, Shugang Kang, and Marco Lovati
Earth Surf. Dynam., 12, 953–971, https://doi.org/10.5194/esurf-12-953-2024, https://doi.org/10.5194/esurf-12-953-2024, 2024
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In this study, we investigated the geomorphology, sedimentology, and chronology of Tuanjie (seven terraces) and Taiping (three terraces) terraces in Diexi, eastern Tibetan Plateau. Results highlight that two damming and three outburst events occurred in the area during the late Pleistocene, and the outburst floods have been a major factor in the formation of tectonically active mountainous river terraces. Tectonic activity and climatic changes play a minor role.
Jens Martin Turowski, Fergus McNab, Aaron Bufe, and Stefanie Tofelde
EGUsphere, https://doi.org/10.5194/egusphere-2024-2342, https://doi.org/10.5194/egusphere-2024-2342, 2024
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Channel belts comprise the area that is affected by a river due to lateral migration and floods. As a landform, they affect local water resources, flood hazard, and often host unique ecological communities. Here, we develop a model describing the evolution of channel belt area over time. The model connects the behaviour of the river to the evolution of the channel belt over a timescale of centuries. A comparison to selected data from experiments and real river systems is favourable.
Andrew Hollyday, Maureen E. Raymo, Jacqueline Austermann, Fred Richards, Mark Hoggard, and Alessio Rovere
Earth Surf. Dynam., 12, 883–905, https://doi.org/10.5194/esurf-12-883-2024, https://doi.org/10.5194/esurf-12-883-2024, 2024
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Sea level was significantly higher during the Pliocene epoch, around 3 million years ago. The present-day elevations of shorelines that formed in the past provide a data constraint on the extent of ice sheet melt and the global sea level response under warm Pliocene conditions. In this study, we identify 10 escarpments that formed from wave-cut erosion during Pliocene times and compare their elevations with model predictions of solid Earth deformation processes to estimate past sea level.
Gregory A. Ruetenik, Ken L. Ferrier, and Odin Marc
Earth Surf. Dynam., 12, 863–881, https://doi.org/10.5194/esurf-12-863-2024, https://doi.org/10.5194/esurf-12-863-2024, 2024
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Fluvial sediment fluxes increased dramatically in Taiwan during Typhoon Morakot in 2009, which produced some of the heaviest landsliding on record. We analyzed fluvial discharge and suspended sediment concentration data at 87 gauging stations across Taiwan to quantify fluvial sediment responses since Morakot. In basins heavily impacted by landsliding, rating curve coefficients sharply increased during Morakot and then declined exponentially with a characteristic decay time of <10 years.
Nil Carrion-Bertran, Albert Falqués, Francesca Ribas, Daniel Calvete, Rinse de Swart, Ruth Durán, Candela Marco-Peretó, Marta Marcos, Angel Amores, Tim Toomey, Àngels Fernández-Mora, and Jorge Guillén
Earth Surf. Dynam., 12, 819–839, https://doi.org/10.5194/esurf-12-819-2024, https://doi.org/10.5194/esurf-12-819-2024, 2024
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The sensitivity to the wave and sea-level forcing sources in predicting a 6-month embayed beach evolution is assessed using two different morphodynamic models. After a successful model calibration using in situ data, other sources are applied. The wave source choice is critical: hindcast data provide wrong results due to an angle bias, whilst the correct dynamics are recovered with the wave conditions from an offshore buoy. The use of different sea-level sources gives no significant differences.
Abhishek Kashyap, Kristen Cook, and Mukunda Dev Behera
EGUsphere, https://doi.org/10.5194/egusphere-2024-1618, https://doi.org/10.5194/egusphere-2024-1618, 2024
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High-mountain floods exhibit a significant geomorphic hazard, often triggered by rapid snowmelt, extreme precipitation, glacial lake outbursts, and natural failures of dams. Such high-magnitude floods can have catastrophic impacts on downstream communities, ecosystems, and infrastructure. These floods demonstrate the significance of understanding the complex interaction of climatic, hydrological, and geological forces in high mountain regions.
Thomas J. Barnes, Thomas V. Schuler, Simon Filhol, and Karianne S. Lilleøren
Earth Surf. Dynam., 12, 801–818, https://doi.org/10.5194/esurf-12-801-2024, https://doi.org/10.5194/esurf-12-801-2024, 2024
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In this paper, we use machine learning to automatically outline landforms based on their characteristics. We test several methods to identify the most accurate and then proceed to develop the most accurate to improve its accuracy further. We manage to outline landforms with 65 %–75 % accuracy, at a resolution of 10 m, thanks to high-quality/high-resolution elevation data. We find that it is possible to run this method at a country scale to quickly produce landform inventories for future studies.
Eric Petersen, Regine Hock, and Michael G. Loso
Earth Surf. Dynam., 12, 727–745, https://doi.org/10.5194/esurf-12-727-2024, https://doi.org/10.5194/esurf-12-727-2024, 2024
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Ice cliffs are melt hot spots that increase melt rates on debris-covered glaciers which otherwise see a reduction in melt rates. In this study, we show how surface runoff streams contribute to the generation, evolution, and survival of ice cliffs by carving into the glacier and transporting rocky debris. On Kennicott Glacier, Alaska, 33 % of ice cliffs are actively influenced by streams, while nearly half are within 10 m of streams.
Daniel O'Hara, Liran Goren, Roos M. J. van Wees, Benjamin Campforts, Pablo Grosse, Pierre Lahitte, Gabor Kereszturi, and Matthieu Kervyn
Earth Surf. Dynam., 12, 709–726, https://doi.org/10.5194/esurf-12-709-2024, https://doi.org/10.5194/esurf-12-709-2024, 2024
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Understanding how volcanic edifices develop drainage basins remains unexplored in landscape evolution. Using digital evolution models of volcanoes with varying ages, we quantify the geometries of their edifices and associated drainage basins through time. We find that these metrics correlate with edifice age and are thus useful indicators of a volcano’s history. We then develop a generalized model for how volcano basins develop and compare our results to basin evolution in other settings.
Brayden Noh, Omar Wani, Kieran B. J. Dunne, and Michael P. Lamb
Earth Surf. Dynam., 12, 691–708, https://doi.org/10.5194/esurf-12-691-2024, https://doi.org/10.5194/esurf-12-691-2024, 2024
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In this paper, we propose a framework for generating risk maps that provide the probabilities of erosion due to river migration. This framework uses concepts from probability theory to learn the river migration model's parameter values from satellite data while taking into account parameter uncertainty. Our analysis shows that such geomorphic risk estimation is more reliable than models that do not explicitly consider various sources of variability and uncertainty.
Steven Y. J. Lai, David Amblas, Aaron Micallef, and Hervé Capart
Earth Surf. Dynam., 12, 621–640, https://doi.org/10.5194/esurf-12-621-2024, https://doi.org/10.5194/esurf-12-621-2024, 2024
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This study explores the creation of submarine canyons and hanging-wall fans on active faults, which can be defined by gravity-dominated breaching and underflow-dominated diffusion processes. The study reveals the self-similarity in canyon–fan long profiles, uncovers Hack’s scaling relationship and proposes a formula to estimate fan volume using canyon length. This is validated by global data from source-to-sink systems, providing insights into deep-water sedimentary processes.
Anuska Narayanan, Sagy Cohen, and John R. Gardner
Earth Surf. Dynam., 12, 581–599, https://doi.org/10.5194/esurf-12-581-2024, https://doi.org/10.5194/esurf-12-581-2024, 2024
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This study investigates the profound impact of deforestation in the Amazon on sediment dynamics. Novel remote sensing data and statistical analyses reveal significant changes, especially in heavily deforested regions, with rapid effects within a year. In less disturbed areas, a 1- to 2-year lag occurs, influenced by natural sediment shifts and human activities. These findings highlight the need to understand the consequences of human activity for our planet's future.
Jacob Hardt, Tim P. Dooley, and Michael R. Hudec
Earth Surf. Dynam., 12, 559–579, https://doi.org/10.5194/esurf-12-559-2024, https://doi.org/10.5194/esurf-12-559-2024, 2024
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We investigate the reaction of salt structures on ice sheet transgressions. We used a series of sandbox models that enabled us to experiment with scaled-down versions of salt bodies from northern Germany. The strongest reactions occurred when large salt pillows were partly covered by the ice load. Subsurface salt structures may play an important role in the energy transition, e.g., as energy storage. Thus, it is important to understand all processes that affect their stability.
Jon D. Pelletier, Robert G. Hayes, Olivia Hoch, Brendan Fenerty, and Luke A. McGuire
EGUsphere, https://doi.org/10.5194/egusphere-2024-1153, https://doi.org/10.5194/egusphere-2024-1153, 2024
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On the gently sloping landscapes next to mountain fronts, junction angles tend to be lower (more acute), while in bedrock landscapes where the initial landscape or tectonic forcing is likely more spatially variable, junction angles tend to be larger (more obtuse). We demonstrate this using an analysis of ~20 million junction angles for the U.S.A., augmented by analyses of the Loess Plateau, China, and synthetic landscapes.
Julius Reich and Axel Winterscheid
EGUsphere, https://doi.org/10.5194/egusphere-2024-579, https://doi.org/10.5194/egusphere-2024-579, 2024
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Analysing the geometry and the dynamics of riverine bedforms (so-called dunetracking) is important for various fields of application and contributes to a sound and efficient river and sediment management. We developed a new tool, which enables a robust estimation of bedform characteristics and with which comprehensive sensitivity analyses can be carried out. Using a test dataset, we show that the selection of input parameters of dunetracking tools can have a significant impact on the results.
Alexander B. Prescott, Jon D. Pelletier, Satya Chataut, and Sriram Ananthanarayan
EGUsphere, https://doi.org/10.5194/egusphere-2024-1138, https://doi.org/10.5194/egusphere-2024-1138, 2024
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Many Earth surface processes are controlled by the spatial pattern of surface water flow. We review commonly used methods for predicting such spatial patterns in digital landform models and document the pros and cons of commonly used methods. We propose a new method that is designed to minimize those limitations and show that it works well in a variety of test cases.
Prakash Pokhrel, Mikael Attal, Hugh D. Sinclair, Simon M. Mudd, and Mark Naylor
Earth Surf. Dynam., 12, 515–536, https://doi.org/10.5194/esurf-12-515-2024, https://doi.org/10.5194/esurf-12-515-2024, 2024
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Pebbles become increasingly rounded during downstream transport in rivers due to abrasion. This study quantifies pebble roundness along the length of two Himalayan rivers. We demonstrate that roundness increases with downstream distance and that the rates are dependent on rock type. We apply this to reconstructing travel distances and hence the size of ancient Himalaya. Results show that the ancient river network was larger than the modern one, indicating that there has been river capture.
Janbert Aarnink, Tom Beucler, Marceline Vuaridel, and Virginia Ruiz-Villanueva
EGUsphere, https://doi.org/10.5194/egusphere-2024-792, https://doi.org/10.5194/egusphere-2024-792, 2024
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This study presents a novel CNN approach for detecting instream large wood in rivers, addressing the need for flexible monitoring methods that can be used on a variety of data sources. Leveraging a database of 15,228 fully labeled images, our model achieved a 67 % weighted mean average precision. Fine-tuning parameters and sampling techniques offer potential for further performance enhancement of more than 10 % in certain cases, promising valuable insights for ecosystem management.
Aline Zinelabedin, Joel Mohren, Maria Wierzbicka-Wieczorek, Tibor Janos Dunai, Stefan Heinze, and Benedikt Ritter
EGUsphere, https://doi.org/10.5194/egusphere-2024-592, https://doi.org/10.5194/egusphere-2024-592, 2024
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In order to interpret the formation processes of subsurface salt wedges and polygonal patterned grounds from the northern Atacama Desert, we present a multi-methodological approach. Due to the high salt content of the wedges, we suggest that their formation is dominated by subsurface salt dynamics requiring moisture. We assume that the climatic conditions during the wedge growth were slightly wetter than today, offering the potential to use the wedges as palaeoclimate archives.
Jens Martin Turowski, Aaron Bufe, and Stefanie Tofelde
Earth Surf. Dynam., 12, 493–514, https://doi.org/10.5194/esurf-12-493-2024, https://doi.org/10.5194/esurf-12-493-2024, 2024
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Fluvial valleys are ubiquitous landforms, and understanding their formation and evolution affects a wide range of disciplines from archaeology and geology to fish biology. Here, we develop a model to predict the width of fluvial valleys for a wide range of geographic conditions. In the model, fluvial valley width is controlled by the two competing factors of lateral channel mobility and uplift. The model complies with available data and yields a broad range of quantitative predictions.
Dominik Amschwand, Jonas Wicky, Martin Scherler, Martin Hoelzle, Bernhard Krummenacher, Anna Haberkorn, Christian Kienholz, and Hansueli Gubler
EGUsphere, https://doi.org/10.5194/egusphere-2024-172, https://doi.org/10.5194/egusphere-2024-172, 2024
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Rock glaciers are comparatively climate-resilient coarse-debris permafrost landforms. We estimate the energy budget of the seasonally thawing active layer (AL) of rock glacier Murtèl (Swiss Alps) based on a novel sub-surface sensor array. In the coarse-blocky AL during the thaw season, heat is transferred by thermal radiation and air convection. The ground heat flux is largely used to melt ground ice in the AL that protects to some degree the permafrost body beneath.
Daniel J. Ciarletta, Jennifer L. Miselis, Julie C. Bernier, and Arnell S. Forde
Earth Surf. Dynam., 12, 449–475, https://doi.org/10.5194/esurf-12-449-2024, https://doi.org/10.5194/esurf-12-449-2024, 2024
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We reconstructed the evolution of Fire Island, a barrier island in New York, USA, to identify drivers of landscape change. Results reveal Fire Island was once divided into multiple inlet-separated islands with distinct features. Later, inlets closed, and Fire Island’s landscape became more uniform as human activities intensified. The island is now less mobile and less likely to resist and recover from storm impacts and sea level rise. This vulnerability may exist for other stabilized barriers.
Chao Zhou, Xibin Tan, Yiduo Liu, and Feng Shi
Earth Surf. Dynam., 12, 433–448, https://doi.org/10.5194/esurf-12-433-2024, https://doi.org/10.5194/esurf-12-433-2024, 2024
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The drainage-divide stability provides new insights into both the river network evolution and the tectonic and/or climatic changes. Several methods have been proposed to determine the direction of drainage-divide migration. However, how to quantify the migration rate of drainage divides remains challenging. In this paper, we propose a new method to calculate the migration rate of drainage divides from high-resolution topographic data.
Moritz Altmann, Madlene Pfeiffer, Florian Haas, Jakob Rom, Fabian Fleischer, Tobias Heckmann, Livia Piermattei, Michael Wimmer, Lukas Braun, Manuel Stark, Sarah Betz-Nutz, and Michael Becht
Earth Surf. Dynam., 12, 399–431, https://doi.org/10.5194/esurf-12-399-2024, https://doi.org/10.5194/esurf-12-399-2024, 2024
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We show a long-term erosion monitoring of several sections on Little Ice Age lateral moraines with derived sediment yield from historical and current digital elevation modelling (DEM)-based differences. The first study period shows a clearly higher range of variability of sediment yield within the sites than the later periods. In most cases, a decreasing trend of geomorphic activity was observed.
Paul A. Carling
Earth Surf. Dynam., 12, 381–397, https://doi.org/10.5194/esurf-12-381-2024, https://doi.org/10.5194/esurf-12-381-2024, 2024
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Edge rounding in Shap granite glacial erratics is an irregular function of distance from the source outcrop in northern England, UK. Block shape is conservative, evolving according to block fracture mechanics – stochastic and silver ratio models – towards either of two attractor states. Progressive reduction in size occurs for blocks transported at the sole of the ice mass where the blocks are subject to compressive and tensile forces of the ice acting against a bedrock or till surface.
Gary Parker, Chenge An, Michael P. Lamb, Marcelo H. Garcia, Elizabeth H. Dingle, and Jeremy G. Venditti
Earth Surf. Dynam., 12, 367–380, https://doi.org/10.5194/esurf-12-367-2024, https://doi.org/10.5194/esurf-12-367-2024, 2024
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River morphology has traditionally been divided by the size 2 mm. We use dimensionless arguments to show that particles in the 1–5 mm range (i) are the finest range not easily suspended by alluvial flood flows, (ii) are transported preferentially over coarser gravel, and (iii), within limits, are also transported preferentially over sand. We show how fluid viscosity mediates the special status of sediment in this range.
Lindsay Marie Capito, Enrico Pandrin, Walter Bertoldi, Nicola Surian, and Simone Bizzi
Earth Surf. Dynam., 12, 321–345, https://doi.org/10.5194/esurf-12-321-2024, https://doi.org/10.5194/esurf-12-321-2024, 2024
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We propose that the pattern of erosion and deposition from repeat topographic surveys can be a proxy for path length in gravel-bed rivers. With laboratory and field data, we applied tools from signal processing to quantify this periodicity and used these path length estimates to calculate sediment transport using the morphological method. Our results highlight the potential to expand the use of the morphological method using only remotely sensed data as well as its limitations.
Caroline Fenske, Jean Braun, François Guillocheau, and Cécile Robin
EGUsphere, https://doi.org/10.5194/egusphere-2024-160, https://doi.org/10.5194/egusphere-2024-160, 2024
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We have developed a new numerical model to represent the formation of ferricretes which are iron-rich, hard layers found in soils and at the surface of the Earth. We assume that the formation mechanism implies variations in the height of the water table and that the hardening rate is proportional to precipitation. The model allows us to quantify the potential feedbacks they generate on the surface topography and the thickness of the regolith/soil layer.
Xuxu Wu, Jonathan Malarkey, Roberto Fernández, Jaco H. Baas, Ellen Pollard, and Daniel R. Parsons
Earth Surf. Dynam., 12, 231–247, https://doi.org/10.5194/esurf-12-231-2024, https://doi.org/10.5194/esurf-12-231-2024, 2024
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The seabed changes from flat to rippled in response to the frictional influence of waves and currents. This experimental study has shown that the speed of this change, the size of ripples that result and even whether ripples appear also depend on the amount of sticky mud present. This new classification on the basis of initial mud content should lead to improvements in models of seabed change in present environments by engineers and the interpretation of past environments by geologists.
Andrea D'Alpaos, Davide Tognin, Laura Tommasini, Luigi D'Alpaos, Andrea Rinaldo, and Luca Carniello
Earth Surf. Dynam., 12, 181–199, https://doi.org/10.5194/esurf-12-181-2024, https://doi.org/10.5194/esurf-12-181-2024, 2024
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Sediment erosion induced by wind waves is one of the main drivers of the morphological evolution of shallow tidal environments. However, a reliable description of erosion events for the long-term morphodynamic modelling of tidal systems is still lacking. By statistically characterizing sediment erosion dynamics in the Venice Lagoon over the last 4 centuries, we set up a novel framework for a synthetic, yet reliable, description of erosion events in tidal systems.
Davide Tognin, Andrea D'Alpaos, Luigi D'Alpaos, Andrea Rinaldo, and Luca Carniello
Earth Surf. Dynam., 12, 201–218, https://doi.org/10.5194/esurf-12-201-2024, https://doi.org/10.5194/esurf-12-201-2024, 2024
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Reliable quantification of sediment transport processes is necessary to understand the fate of shallow tidal environments. Here we present a framework for the description of suspended sediment dynamics to quantify deposition in the long-term modelling of shallow tidal systems. This characterization, together with that of erosion events, allows one to set up synthetic, yet reliable, models for the long-term evolution of tidal landscapes.
Emma L. S. Graf, Hugh D. Sinclair, Mikaël Attal, Boris Gailleton, Basanta Raj Adhikari, and Bishnu Raj Baral
Earth Surf. Dynam., 12, 135–161, https://doi.org/10.5194/esurf-12-135-2024, https://doi.org/10.5194/esurf-12-135-2024, 2024
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Using satellite images, we show that, unlike other examples of earthquake-affected rivers, the rivers of central Nepal experienced little increase in sedimentation following the 2015 Gorkha earthquake. Instead, a catastrophic flood occurred in 2021 that buried towns and agricultural land under up to 10 m of sediment. We show that intense storms remobilised glacial sediment from high elevations causing much a greater impact than flushing of earthquake-induced landslides.
Mohamad Nasr, Adele Johannot, Thomas Geay, Sebastien Zanker, Jules Le Guern, and Alain Recking
Earth Surf. Dynam., 12, 117–134, https://doi.org/10.5194/esurf-12-117-2024, https://doi.org/10.5194/esurf-12-117-2024, 2024
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Hydrophones are used to monitor sediment transport in the river by listening to the acoustic noise generated by particle impacts on the riverbed. However, this acoustic noise is modified by the river flow and can cause misleading information about sediment transport. This article proposes a model that corrects the measured acoustic signal. Testing the model showed that the corrected signal is better correlated with bedload flux in the river.
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Short summary
Sand dune migration velocity is inversely proportional to dune size. Consequently, smaller, faster dunes can collide with larger, slower downstream dunes. Such collisions can result in either coalescence or ejection, whereby the dunes exchange mass but remain separate. Our numerical simulations show that the outcome depends probabilistically on the dune size ratio, which we describe through an empirical function. Our numerical predictions compare favourably against experimental observations.
Sand dune migration velocity is inversely proportional to dune size. Consequently, smaller,...
