Articles | Volume 9, issue 3
https://doi.org/10.5194/esurf-9-539-2021
© Author(s) 2021. 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-9-539-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
16 Jun 2021
Research article | Highlight paper |
| 16 Jun 2021
| 16 Jun 2021
Rarefied particle motions on hillslopes – Part 1: Theory
David Jon Furbish
CORRESPONDING AUTHOR
Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
Joshua J. Roering
Department of Earth Sciences, University of Oregon, Eugene, Oregon, USA
Tyler H. Doane
Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
currently at: Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, Indiana, USA
Danica L. Roth
Department of Earth Sciences, University of Oregon, Eugene, Oregon, USA
currently at: Department of Geology and Geological Engineering, Colorado School of Mines, Golden, Colorado, USA
Sarah G. W. Williams
Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
Angel M. Abbott
formerly at: Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
deceased, 10 August 2018
Related authors
Sarah G. W. Williams and David J. Furbish
Earth Surf. Dynam., 9, 701–721, https://doi.org/10.5194/esurf-9-701-2021, https://doi.org/10.5194/esurf-9-701-2021, 2021
Short summary
Short summary
Particle motions and travel distances prior to deposition on hillslope surfaces depend on a balance of gravitational and frictional forces. We elaborate how particle energy is partitioned and dissipated during travel using measurements of particle travel distances supplemented with high-speed imaging of drop–impact–rebound experiments. Results show that particle shape plays a dominant role in how energy is partitioned during impact with a surface and how far particles travel in two dimensions.
David Jon Furbish, Sarah G. W. Williams, Danica L. Roth, Tyler H. Doane, and Joshua J. Roering
Earth Surf. Dynam., 9, 577–613, https://doi.org/10.5194/esurf-9-577-2021, https://doi.org/10.5194/esurf-9-577-2021, 2021
Short summary
Short summary
The generalized Pareto distribution of particle travel distances on steep hillslopes, as described in a companion paper (Furbish et al., 2021a), is entirely consistent with measurements of travel distances obtained from laboratory and field-based experiments, supplemented with high-speed imaging and audio recordings that highlight the effects of bumpety-bump particle motions. Particle size and shape, in concert with surface roughness, strongly influence particle energetics and deposition.
David Jon Furbish, Sarah G. W. Williams, and Tyler H. Doane
Earth Surf. Dynam., 9, 615–628, https://doi.org/10.5194/esurf-9-615-2021, https://doi.org/10.5194/esurf-9-615-2021, 2021
Short summary
Short summary
The generalized Pareto distribution of particle travel distances on steep hillslopes, as described in two companion papers (Furbish et al., 2021a, 2021b), is a maximum entropy distribution. This simply represents the most probable way that a great number of particles become distributed into distance states, subject to a fixed total energetic cost due to frictional effects of particle–surface collisions. The maximum entropy criterion is equivalent to a formal application of Occam's razor.
David Jon Furbish and Tyler H. Doane
Earth Surf. Dynam., 9, 629–664, https://doi.org/10.5194/esurf-9-629-2021, https://doi.org/10.5194/esurf-9-629-2021, 2021
Short summary
Short summary
Using analyses of particle motions on steep hillslopes in three companion papers (Furbish et al., 2021a, 2021b, 2021c), we offer philosophical perspective on the merits of a statistical mechanics framework for describing sediment particle motions and transport, and the implications of rarefied versus continuum transport conditions. We highlight the mechanistic yet probabilistic nature of the approach, and the importance of tailoring the style of thinking to the process and scale of interest.
Shawn M. Chartrand and David Jon Furbish
Earth Surf. Dynam. Discuss., https://doi.org/10.5194/esurf-2021-16, https://doi.org/10.5194/esurf-2021-16, 2021
Preprint withdrawn
Short summary
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Sediment particles are transported along the bottom of rivers during floods. Descriptions of the transport process are commonly restricted to the strength of the water flow. In our research we use mathematical theory and data from laboratory experiments to explore whether sediment particles colliding with the river bed can help explain our observations of transport. We learn that particle collisions are likely an important component of the transport process and we offer thoughts for future work.
David Jon Furbish, Rina Schumer, and Amanda Keen-Zebert
Earth Surf. Dynam., 6, 1169–1202, https://doi.org/10.5194/esurf-6-1169-2018, https://doi.org/10.5194/esurf-6-1169-2018, 2018
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We present in this mostly theoretical contribution a systematic treatment of tracer particle mixing in soils. We elaborate the consequences of rarefied (non-continuum) conditions of transport and mixing, and we augment this with numerical analyses that reveal important information not readily apparent in the analytical formulations, including an illustration of the variability in 10Be concentrations and OSL ages of individual particles in soils, with implications for interpreting field data.
Stuart W. D. Grieve, Simon M. Mudd, David T. Milodowski, Fiona J. Clubb, and David J. Furbish
Earth Surf. Dynam., 4, 627–653, https://doi.org/10.5194/esurf-4-627-2016, https://doi.org/10.5194/esurf-4-627-2016, 2016
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High-resolution topographic data are becoming more prevalent, yet many areas of geomorphic interest do not have such data available. We produce topographic data at a range of resolutions to explore the influence of decreasing resolution of data on geomorphic analysis. We test the accuracy of the calculation of curvature, a hillslope sediment transport coefficient, and the identification of channel networks, providing guidelines for future use of these methods on low-resolution topographic data.
Ian D. Wachino, Joshua J. Roering, Reuben Cash, and Annette I. Patton
EGUsphere, https://doi.org/10.5194/egusphere-2025-1168, https://doi.org/10.5194/egusphere-2025-1168, 2025
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Rockfalls are a common hazard in steep mountain valleys, especially near Skagway, Alaska, where recent events have threatened public safety and infrastructure. This study identifies zones prone to rockfall by analyzing rock formations, past rockfall deposits, and computer models predicting how rocks travel downslope. Our findings highlight high-risk areas and provide insights to improve hazard mitigation, helping protect communities and tourism in the region.
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.
Greg Balco, Alan J. Hidy, William T. Struble, and Joshua J. Roering
Geochronology, 6, 71–76, https://doi.org/10.5194/gchron-6-71-2024, https://doi.org/10.5194/gchron-6-71-2024, 2024
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We describe a new method of reconstructing the long-term, pre-observational frequency and/or intensity of wildfires in forested landscapes using trace concentrations of the noble gases helium and neon that are formed in soil mineral grains by cosmic-ray bombardment of the Earth's surface.
Annette I. Patton, Lisa V. Luna, Joshua J. Roering, Aaron Jacobs, Oliver Korup, and Benjamin B. Mirus
Nat. Hazards Earth Syst. Sci., 23, 3261–3284, https://doi.org/10.5194/nhess-23-3261-2023, https://doi.org/10.5194/nhess-23-3261-2023, 2023
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Landslide warning systems often use statistical models to predict landslides based on rainfall. They are typically trained on large datasets with many landslide occurrences, but in rural areas large datasets may not exist. In this study, we evaluate which statistical model types are best suited to predicting landslides and demonstrate that even a small landslide inventory (five storms) can be used to train useful models for landslide early warning when non-landslide events are also included.
William T. Struble and Joshua J. Roering
Earth Surf. Dynam., 9, 1279–1300, https://doi.org/10.5194/esurf-9-1279-2021, https://doi.org/10.5194/esurf-9-1279-2021, 2021
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We used a mathematical technique known as a wavelet transform to calculate the curvature of hilltops in western Oregon, which we used to estimate erosion rate. We find that this technique operates over 1000 times faster than other techniques and produces accurate erosion rates. We additionally built artificial hillslopes to test the accuracy of curvature measurement methods. We find that at fast erosion rates, curvature is underestimated, raising questions of measurement accuracy elsewhere.
Sarah G. W. Williams and David J. Furbish
Earth Surf. Dynam., 9, 701–721, https://doi.org/10.5194/esurf-9-701-2021, https://doi.org/10.5194/esurf-9-701-2021, 2021
Short summary
Short summary
Particle motions and travel distances prior to deposition on hillslope surfaces depend on a balance of gravitational and frictional forces. We elaborate how particle energy is partitioned and dissipated during travel using measurements of particle travel distances supplemented with high-speed imaging of drop–impact–rebound experiments. Results show that particle shape plays a dominant role in how energy is partitioned during impact with a surface and how far particles travel in two dimensions.
David Jon Furbish, Sarah G. W. Williams, Danica L. Roth, Tyler H. Doane, and Joshua J. Roering
Earth Surf. Dynam., 9, 577–613, https://doi.org/10.5194/esurf-9-577-2021, https://doi.org/10.5194/esurf-9-577-2021, 2021
Short summary
Short summary
The generalized Pareto distribution of particle travel distances on steep hillslopes, as described in a companion paper (Furbish et al., 2021a), is entirely consistent with measurements of travel distances obtained from laboratory and field-based experiments, supplemented with high-speed imaging and audio recordings that highlight the effects of bumpety-bump particle motions. Particle size and shape, in concert with surface roughness, strongly influence particle energetics and deposition.
David Jon Furbish, Sarah G. W. Williams, and Tyler H. Doane
Earth Surf. Dynam., 9, 615–628, https://doi.org/10.5194/esurf-9-615-2021, https://doi.org/10.5194/esurf-9-615-2021, 2021
Short summary
Short summary
The generalized Pareto distribution of particle travel distances on steep hillslopes, as described in two companion papers (Furbish et al., 2021a, 2021b), is a maximum entropy distribution. This simply represents the most probable way that a great number of particles become distributed into distance states, subject to a fixed total energetic cost due to frictional effects of particle–surface collisions. The maximum entropy criterion is equivalent to a formal application of Occam's razor.
David Jon Furbish and Tyler H. Doane
Earth Surf. Dynam., 9, 629–664, https://doi.org/10.5194/esurf-9-629-2021, https://doi.org/10.5194/esurf-9-629-2021, 2021
Short summary
Short summary
Using analyses of particle motions on steep hillslopes in three companion papers (Furbish et al., 2021a, 2021b, 2021c), we offer philosophical perspective on the merits of a statistical mechanics framework for describing sediment particle motions and transport, and the implications of rarefied versus continuum transport conditions. We highlight the mechanistic yet probabilistic nature of the approach, and the importance of tailoring the style of thinking to the process and scale of interest.
Tyler H. Doane, Jon D. Pelletier, and Mary H. Nichols
Earth Surf. Dynam., 9, 317–331, https://doi.org/10.5194/esurf-9-317-2021, https://doi.org/10.5194/esurf-9-317-2021, 2021
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This paper explores how the geometry of rill networks contributes to observed nonlinear relationships between soil loss and hillslope length. This work develops probability functions of geometrical quantities of the networks and then extends the theory to hydraulic variables by relying on well-known relationships. Theory is complemented by numerical modeling on numerical and natural surfaces. Results suggest that the particular arrangement of rill networks contributes to nonlinear relationships.
Shawn M. Chartrand and David Jon Furbish
Earth Surf. Dynam. Discuss., https://doi.org/10.5194/esurf-2021-16, https://doi.org/10.5194/esurf-2021-16, 2021
Preprint withdrawn
Short summary
Short summary
Sediment particles are transported along the bottom of rivers during floods. Descriptions of the transport process are commonly restricted to the strength of the water flow. In our research we use mathematical theory and data from laboratory experiments to explore whether sediment particles colliding with the river bed can help explain our observations of transport. We learn that particle collisions are likely an important component of the transport process and we offer thoughts for future work.
David Jon Furbish, Rina Schumer, and Amanda Keen-Zebert
Earth Surf. Dynam., 6, 1169–1202, https://doi.org/10.5194/esurf-6-1169-2018, https://doi.org/10.5194/esurf-6-1169-2018, 2018
Short summary
Short summary
We present in this mostly theoretical contribution a systematic treatment of tracer particle mixing in soils. We elaborate the consequences of rarefied (non-continuum) conditions of transport and mixing, and we augment this with numerical analyses that reveal important information not readily apparent in the analytical formulations, including an illustration of the variability in 10Be concentrations and OSL ages of individual particles in soils, with implications for interpreting field data.
Susan L. Brantley, David M. Eissenstat, Jill A. Marshall, Sarah E. Godsey, Zsuzsanna Balogh-Brunstad, Diana L. Karwan, Shirley A. Papuga, Joshua Roering, Todd E. Dawson, Jaivime Evaristo, Oliver Chadwick, Jeffrey J. McDonnell, and Kathleen C. Weathers
Biogeosciences, 14, 5115–5142, https://doi.org/10.5194/bg-14-5115-2017, https://doi.org/10.5194/bg-14-5115-2017, 2017
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This review represents the outcome from an invigorating workshop discussion that involved tree physiologists, geomorphologists, ecologists, geochemists, and hydrologists and developed nine hypotheses that could be tested. We argue these hypotheses point to the essence of issues we must explore if we are to understand how the natural system of the earth surface evolves, and how humans will affect its evolution. This paper will create discussion and interest both before and after publication.
Stuart W. D. Grieve, Simon M. Mudd, David T. Milodowski, Fiona J. Clubb, and David J. Furbish
Earth Surf. Dynam., 4, 627–653, https://doi.org/10.5194/esurf-4-627-2016, https://doi.org/10.5194/esurf-4-627-2016, 2016
Short summary
Short summary
High-resolution topographic data are becoming more prevalent, yet many areas of geomorphic interest do not have such data available. We produce topographic data at a range of resolutions to explore the influence of decreasing resolution of data on geomorphic analysis. We test the accuracy of the calculation of curvature, a hillslope sediment transport coefficient, and the identification of channel networks, providing guidelines for future use of these methods on low-resolution topographic data.
Related subject area
Physical: Geomorphology (including all aspects of fluvial, coastal, aeolian, hillslope and glacial geomorphology)
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Influence of alluvial slope on avulsion in river deltas
Surficial sediment remobilization by shear between sediment and water above tsunamigenic megathrust ruptures: experimental study
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Evidence of slow millennial cliff retreat rates using cosmogenic nuclides in coastal colluvium
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Spatiotemporal denudation rates of the Swabian Alb escarpment (Southwest Germany) dominated by base-level lowering and lithology
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Large structure simulation for landscape evolution models
Investigating the celerity of propagation for small perturbations and dispersive sediment aggradation under a supercritical flow
Terrace formation linked to outburst floods at the Diexi palaeo-landslide dam, upper Minjiang River, eastern Tibetan Plateau
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Larry Syu-Heng Lai, Adam M. Booth, Alison R. Duvall, and Erich Herzig
Earth Surf. Dynam., 13, 417–435, https://doi.org/10.5194/esurf-13-417-2025, https://doi.org/10.5194/esurf-13-417-2025, 2025
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Dominik Amschwand, Jonas Wicky, Martin Scherler, Martin Hoelzle, Bernhard Krummenacher, Anna Haberkorn, Christian Kienholz, and Hansueli Gubler
Earth Surf. Dynam., 13, 365–401, https://doi.org/10.5194/esurf-13-365-2025, https://doi.org/10.5194/esurf-13-365-2025, 2025
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Rock glaciers are comparatively climate-robust permafrost landforms. We estimated the energy budget of the seasonally thawing active layer (AL) of Murtèl rock glacier (Swiss Alps) based on a novel sub-surface sensor array. In the coarse blocky AL, heat is transferred by thermal radiation and air convection. The ground heat flux is largely spent on melting seasonal ice in the AL. Convective cooling and the seasonal ice turnover make rock glaciers climate-robust and shield the permafrost beneath.
Octria A. Prasojo, Trevor B. Hoey, Amanda Owen, and Richard D. Williams
Earth Surf. Dynam., 13, 349–363, https://doi.org/10.5194/esurf-13-349-2025, https://doi.org/10.5194/esurf-13-349-2025, 2025
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Decades of delta avulsion (i.e. channel abrupt jump) studies have not resolved what the main controls of delta avulsion are. Using a computer model, integrated with field observation, analytical, and laboratory-made deltas, we found that the sediment load, which itself is controlled by the steepness of the river upstream of a delta, controls the timing of avulsion. We can now better understand the main cause of abrupt channel changes in deltas, a finding that aids flood risk management in river deltas.
Chloé Seibert, Cecilia McHugh, Chris Paola, Leonardo Seeber, and James Tucker
Earth Surf. Dynam., 13, 341–348, https://doi.org/10.5194/esurf-13-341-2025, https://doi.org/10.5194/esurf-13-341-2025, 2025
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We propose a new mechanism of co-seismic sediment entrainment induced by shear stress at the sediment–water interface during major subduction earthquakes rupturing to the trench. Physical experiments show that flow velocities consistent with long-period earthquake motions can entrain synthetic marine sediment, and high-frequency vertical shaking can enhance this mobilization. They validate the proposed entrainment mechanism, which opens new avenues for paleoseismology in deep-sea environments.
Aline Zinelabedin, Joel Mohren, Maria Wierzbicka-Wieczorek, Tibor Janos Dunai, Stefan Heinze, and Benedikt Ritter
Earth Surf. Dynam., 13, 257–276, https://doi.org/10.5194/esurf-13-257-2025, https://doi.org/10.5194/esurf-13-257-2025, 2025
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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.
Alexander B. Prescott, Jon D. Pelletier, Satya Chataut, and Sriram Ananthanarayan
Earth Surf. Dynam., 13, 239–256, https://doi.org/10.5194/esurf-13-239-2025, https://doi.org/10.5194/esurf-13-239-2025, 2025
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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.
Jon D. Pelletier, Robert G. Hayes, Olivia Hoch, Brendan Fenerty, and Luke A. McGuire
Earth Surf. Dynam., 13, 219–238, https://doi.org/10.5194/esurf-13-219-2025, https://doi.org/10.5194/esurf-13-219-2025, 2025
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We demonstrate that landscapes with more planar initial conditions tend to have lower mean junction angles. Geomorphic processes on alluvial piedmonts result in especially planar initial conditions, consistent with a correlation between junction angles and the presence/absence of Late Cenozoic alluvial deposits and the constraint imposed by the intersection of planar approximations to the topography upslope from tributary junctions. We caution against using junction angles to infer paleoclimate.
Soichi Tanabe and Toshiki Iwasaki
EGUsphere, https://doi.org/10.5194/egusphere-2025-103, https://doi.org/10.5194/egusphere-2025-103, 2025
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We try to understand how the sediment supply from the upstream river reach affect the downstream river morphology using a numerical model. If the supplied sediment is composed of variety of size class of particles, a small size bed wave that is composed of mainly fine particles (sorting wave) can propagate to downstream very long distance. However, presence of bars suppresses the effect of sorting wave greatly, and thus the sediment supply has limited role in the downstream river morphology.
Janbert Aarnink, Tom Beucler, Marceline Vuaridel, and Virginia Ruiz-Villanueva
Earth Surf. Dynam., 13, 167–189, https://doi.org/10.5194/esurf-13-167-2025, https://doi.org/10.5194/esurf-13-167-2025, 2025
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This study presents a novel convolutional-neural-network approach for detecting instream large wood in rivers, addressing the need for flexible monitoring methods across diverse data sources. Using a database of 15 228 fully labelled images, the model achieved a weighted mean average precision of 67 %. Fine-tuning parameters and sampling techniques can improve performance by over 10 % in some cases, offering valuable insights into ecosystem management.
Julius Reich and Axel Winterscheid
Earth Surf. Dynam., 13, 191–217, https://doi.org/10.5194/esurf-13-191-2025, https://doi.org/10.5194/esurf-13-191-2025, 2025
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Analyzing the geometry and the dynamics of riverine bedforms (so-called dune tracking) is important for various fields of application and contributes to sound and efficient river and sediment management. We developed a workflow that enables a robust estimation of bedform characteristics and with which comprehensive sensitivity analyses can be carried out. Using a field dataset, we show that the setting of input parameters in bedform analyses can have a significant impact on the results.
Abhishek Kashyap, Kristen L. Cook, and Mukunda Dev Behera
Earth Surf. Dynam., 13, 147–166, https://doi.org/10.5194/esurf-13-147-2025, https://doi.org/10.5194/esurf-13-147-2025, 2025
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Short-lived, high-magnitude flood events across high mountain regions leave substantial geomorphic imprints, which are frequently triggered by excess precipitation, glacial lake outbursts, and natural dam breaches. These catastrophic floods highlight the importance of understanding the complex interaction between climatic, hydrological, and geological forces in bedrock catchments. Extreme floods can have long-term geomorphic consequences on river morphology and fluvial processes.
Gareth G. Roberts
EGUsphere, https://doi.org/10.5194/egusphere-2025-307, https://doi.org/10.5194/egusphere-2025-307, 2025
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The use of new Artificial Intelligence (AI) techniques to learn how landscapes evolve is demonstrated. A few ‘snapshots' of an eroding landscape at different stages of its history provide enough information for AI to ascertain rules governing its evolution. Once the rules are known, predicting landscape evolution is extremely rapid and efficient, providing new tools to understand landscape change.
Caroline Fenske, Jean Braun, François Guillocheau, and Cécile Robin
Earth Surf. Dynam., 13, 119–146, https://doi.org/10.5194/esurf-13-119-2025, https://doi.org/10.5194/esurf-13-119-2025, 2025
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We have developed a new numerical model to represent the formation of duricrusts, which are hard mineral 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.
Jens M. Turowski, Fergus McNab, Aaron Bufe, and Stefanie Tofelde
Earth Surf. Dynam., 13, 97–117, https://doi.org/10.5194/esurf-13-97-2025, https://doi.org/10.5194/esurf-13-97-2025, 2025
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Channel belts comprise the area affected by a river due to lateral migration and floods. As a landform, they affect water resources and flood hazard, and they often host unique ecological communities. 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 verifies the random walk approach.
Rémi Bossis, Vincent Regard, Sébastien Carretier, and Sandrine Choy
Earth Surf. Dynam., 13, 71–79, https://doi.org/10.5194/esurf-13-71-2025, https://doi.org/10.5194/esurf-13-71-2025, 2025
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The erosion of rocky coasts occurs episodically through wave action and landslides, constituting a major natural hazard. Documenting the factors that control the coastal retreat rate over millennia is fundamental to evidencing any change in time. However, the known rates to date are essentially representative of the last few decades. Here, we present a new method using the concentration of an isotope, 10Be, in sediment eroded from the cliff to quantify its retreat rate averaged over millennia.
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.
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.
Joshua M. Wolstenholme, Christopher J. Skinner, David J. Milan, Robert E. Thomas, and Daniel R. Parsons
EGUsphere, https://doi.org/10.5194/egusphere-2024-3001, https://doi.org/10.5194/egusphere-2024-3001, 2024
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Leaky wooden dams are a popular form of natural flood management used to slow the flow of water by increasing floodplain connectivity whilst decreasing connectivity along the river profile. By monitoring two leaky wooden dams in North Yorkshire, UK, we present the geomorphological response to their installation, highlighting that the structures significantly increase channel complexity in response to different river flow conditions.
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.
Loïs Ribet, Frédéric Liébault, Laurent Borgniet, Michaël Deschâtres, and Gabriel Melun
EGUsphere, https://doi.org/10.5194/egusphere-2024-3697, https://doi.org/10.5194/egusphere-2024-3697, 2024
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This work presents a protocol and a model to get the size of the pebbles in mountain rivers from Unmanned Aerial Vehicle images. A set of 12 rivers located in south-eastern France were photographed to build the model. The results show that the model has little error and should be usable for similar rivers. Grain-size of mountain rivers is an important parameter for environmental diagnostics by mapping the aquatic habitats and for flood management by estimating the pebbles fluxes during floods.
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.
Lorenzo Durante, Nicoletta Tambroni, and Michele Bolla Pittaluga
EGUsphere, https://doi.org/10.5194/egusphere-2024-3552, https://doi.org/10.5194/egusphere-2024-3552, 2024
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River deltas are dynamic areas where rivers meet the sea. This study examines delta configurations to guide balanced development and environmental health. Using the Po River Delta, we developed a model to understand how different delta parts interact and maintain balance. Our findings show that deltas can reach varied states of balance, with some areas more prone to shift. These insights support predictions of delta changes and better management strategies.
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.
Viktoria Kosmalla, Oliver Lojek, Jana Carus, Kara Keimer, Lukas Ahrenbeck, Björn Mehrtens, David Schürenkamp, Boris Schröder, and Nils Goseberg
EGUsphere, https://doi.org/10.5194/egusphere-2024-2688, https://doi.org/10.5194/egusphere-2024-2688, 2024
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This study analysed seasonal biomechanical traits of marram grass at two coastal dune sites using monthly field and lab data acquired 2022. Differences in density, leaf length, and flower stems were observed, which are unaffected by wind and deemed transferable. These findings enable surrogate model development for numerical and physical experiments alike, where live vegetation is impractical. Results address the knowledge gap how dune stability and erosion resistance are affected by vegetation.
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.
Jingqiu Huang and Hugh D. Sinclair
EGUsphere, https://doi.org/10.5194/egusphere-2024-2600, https://doi.org/10.5194/egusphere-2024-2600, 2024
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This study uses radar technology to track tiny changes in riverbeds elevation in Himalayan Rivers as they flow onto the Gangetic Plains. By analyzing data from 2016 to 2021, we found that sediment builds up in seasonally dry (ephemeral) rivers during monsoon seasons, while the surrounding floodplains is sinking. This research is important for understanding how these elevation changes affect flood risks in rapidly growing communities in Nepal and India. Our findings can improve flood management.
Mirjam Schaller, Daniel Peifer, Alexander B. Neely, Thomas Bernard, Christoph Glotzbach, Alexander R. Beer, and Todd A. Ehlers
EGUsphere, https://doi.org/10.5194/egusphere-2024-2729, https://doi.org/10.5194/egusphere-2024-2729, 2024
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This study reports chemical weathering, physical erosion, and total denudation rates from river load data in the Swabian Alb, Southwest Germany. Tributaries to the Neckar River draining to the North show higher rates than tributaries draining to the South into the Danube River causing a retreat of the Swabian Alb escarpment. Observations are discussed in the light of lithology, climate, and topography. The data are further compared to other rates over space and time as well as to global data.
Riccardo Bonomelli, Marco Pilotti, and Gabriele Farina
EGUsphere, https://doi.org/10.5194/egusphere-2024-2267, https://doi.org/10.5194/egusphere-2024-2267, 2024
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Debris flows are fundamental components of the hazard in mountain regions and numerical models must be used for the related risk computation. Most existing commercial software strongly conceptualizes the main characteristics of the flow, leading to an inevitable calibration process, that is time-consuming and difficult to accomplish. This contribution offers some physically based solutions to confine the calibration process and to better understand the implications of the selected choice.
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.
Hasan Eslami, Erfan Poursoleymanzadeh, Mojtaba Hiteh, Keivan Tavakoli, Melika Yavari Nia, Ehsan Zadehali, Reihaneh Zarrabi, and Alessio Radice
EGUsphere, https://doi.org/10.5194/egusphere-2024-414, https://doi.org/10.5194/egusphere-2024-414, 2024
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A channel may be aggraded by overloaded sediment. In this study we realize an aggradation experiment and determine the celerity at which an aggradation wave, due to sediment overloading, migrates. We also investigate the celerity of small perturbations, as quantified based on mathematical formulations. The celerities of the two kinds are correlated with each other. However, the celerity of small perturbations is larger than the other one, that is less than a few percent of the water velocity.
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.
Hanne Hendrickx, Xabier Blanch, Melanie Elias, Reynald Delaloye, and Anette Eltner
EGUsphere, https://doi.org/10.5194/egusphere-2024-2570, https://doi.org/10.5194/egusphere-2024-2570, 2024
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This study introduces a novel AI-based method to track and analyse the movement of rock glaciers and landslides, key indicators of permafrost dynamics in high mountain regions. Using time-lapse images, our approach provides detailed velocity data, revealing patterns that traditional methods miss. This cost-effective tool enhances our ability to monitor geohazards, offering insights into climate change impacts on permafrost and improving safety in alpine areas.
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.
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.
Cited articles
Almazán, L., Serero, D., Salueña, C., and Pöschel, T.: Energy decay in a granular gas collapse, New J. Phys., 19, 013001, https://doi.org/10.1088/1367-2630/aa5598, 2017.
Ancey, C., Davison, A., Böhm, T., Jodeau, M., and Frey, P.: Entrainment and motion of coarse particles in a shallow water stream down a steep slope, J. Fluid Mech., 595, 83–114, 2008.
Anderson, R. S.: Modeling the tor-dotted crests, bedrock edges, and parabolic profiles of high alpine surfaces of the Wind River Range, Wyoming, Geomorphology, 46, 35–58, 2002.
Atwood-Stone, C. and McEwen, A. S.: Avalanche slope angles in low-gravity environments from active Martian sand dunes, Geophys. Res. Lett., 40, 2929–2934, 2013.
Bagnold, R. A.: Experiments on a gravity-free dispersion of large solid spheres in a Newtonian fluid under shear, P. Roy. Soc. Lond. A, 225, 49–63, 1954.
Baldassarri, A., Barrat, A., D'Anna, G., Loreto, V., Mayor, P., and Puglisi, A.: What is the temperature of a granular medium, J. Phys.: Condens. Matt., 17, S2405–S2428, https://doi.org/10.1088/0953-8984/17/24/003, 2005.
Bendror, E. and Goren, L.: Controls over sediment flux along soil-mantled hillslopes: Insights from granular dynamics simulations, J. Geophys. Res.-Earth, 123, 924–944, https://doi.org/10.1002/2017jf004351, 2018.
Bocquet, L., Colin, A., and Ajdari, A.: Kinetic theory of plastic flow in soft glassy materials, Phys. Rev. Lett., 103, 036001, https://doi.org/10.1103/PhysRevLett.103.036001, 2009.
Brach, R. M.: Friction, restitution, and energy loss in planar collisions, J. Appl. Mech., 51, 164–170, 1984.
Brach, R. M.: Rigid body collisions, J. Appl. Mech., 56, 133–138, 1989.
Brach, R. M.: Mechanical Impact Dynamics, John Wiley, New York, 1991.
Brach, R. M.: Formulation of rigid body impact problems using generalized coefficients, Int. J. Eng. Sci., 36, 61–71, 1998.
Brach, R. M. and Dunn, P. F.: A mathematical model of the impact and adhesion of microsphers, Aerosol Sci. Tech., 16, 51–64, 1992.
Brach, R. M. and Dunn, P. F.: Macrodynamics of microparticles, Aerosol Sci. Tech., 23, 51–71, 1995.
Brantov, A. V. and Bychenkov, V. Yu.: Nonlocal transport in hot plasma. Part I, Plasma Phys. Rep., 39, 698–744, 2013.
Brilliantov, N. V. and Pöschel, T.: Kinetic Theory of Granular Gases, Oxford University Press, New York, 2004.
Brilliantov, N. V. and Pöschel, T.: Self-diffusion in granular gases: Green-Kubo versus Chapman-Enskog, Chaos, 15, 026108, https://doi.org/0.1063/1.1889266, 2005.
Brilliantov, N. V., Formella, A., and Pöschel, T.: Increasing temperature of cooling granular gases, Nat. Commun., 9, 797, https://doi.org/10.1038/s41467-017-02803-7, 2018.
Cates, M. E., Wittmer, J. P., Bouchaud, J.-P., and Claudin, P.: Jamming, force chains, and fragile matter, Phys. Rev. Lett., 81, 1841–1844, 1998.
Chandrasekhar, S.: Stochastic problems in physics and astronomy, Rev. Modern Phys., 15, 1–89, 1943.
Culling, W. E. H.: Soil creep and the development of hillside slopes, J. Geol., 71, 127–161, 1963.
Daniels, K. E. and Behringer, R. P: Characterization of a freezing/melting transition in a vibrated and sheared granular medium, J. Statist. Mech., 2006, P07018, https://doi.org/10.1088/1742-5468/2006/07/P07018, 2006.
Deshpande, N. S., Furbish, D. J., Arratia, P. E., and Jerolmack, D. J.: The perpetual fragility of creeping hillslopes, Nat. Commun., https://doi.org/10.31223/osf.io/qc9jh, in press, 2020.
DiBiase, R. A. and Lamb, M. P.: Vegetation and wildfire controls on sediment yield in bedrock landscapes, Geophys. Res. Lett., 40, 1093–1097, https://doi.org/10.1002/grl.50277, 2013.
DiBiase, R. A., Lamb, M. P., Ganti, V., and Booth, A. M.: Slope, grain size, and roughness controls on dry sediment transport and storage on steep hillslopes, J. Geophys. Res.-Earth, 122, 941–960, https://doi.org/10.1002/2016JF003970, 2017.
Dippel, S., Batrouni, G. G., and Wolf, D. E.: How tranversal fluctuations affect the friction of a particle on a rough incline, Phys. Rev. E, 56, 3645–3656, 1997.
Doane, T. H.: Theory and application of nonlocal hillslope sediment transport, PhD thesis, Vanderbilt University, Nashville, Tennessee, 2018.
Doane, T. H., Furbish, D. J., Roering, J. J., Schumer, R., and Morgan, D. J.: Nonlocal sediment transport on steep lateral moraines, eastern Sierra Nevada, California, USA, J. Geophys. Res.-Earth, 123, 187–208, https://doi.org/10.1002/2017JF004325, 2018.
Doane, T. H., Roth, D. L., Roering, J. J., and Furbish, D. J.: Compression and decay of hillslope topographic variance in Fourier wavenumber domain, J. Geophys. Res.–Earth, 124, 60–79, https://doi.org/10.1029/2018JF004724, 2019.
Dominguez, H. and Zenit, R.: On the cooling law of a non-dilute granular gas, Revista Mexicana de Física, 53, 83–86, 2007.
Dorren, L. K. A.: A review of rockfall mechanics and modelling approaches, Prog. Phys. Geogr., 27, 69–87, 2003.
Einstein, A.: Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen, Ann. Phys., 17, 549–560, 1905.
Feller, W.: On the theory of stochastic processes, with particular reference to applications, in: Proceedings of the [First] Berkeley Symposium on Mathematical Statistics and Probability, University of California Press, Berkeley, California, 403–432, available at: https://projecteuclid.org/euclid.bsmsp/1166219215 (last access: June 2021), 1949.
Ferdowsi, B., Ortiz, C. P., and Jerolmack, D. J.: Glassy dynamics of landscape evolution, P. Natl. Acad. Sci. USA, 115, 4827–4832, 2018.
Forrester, S. F.: Boulder trundling, The Rucksack Club Journal, available at: https://www.amazon.com/Boulder-Trundling-original-Rucksack-Journal/dp/B01LY3C61B (last access: June 2021), 1931.
Forterre, Y. and Pouliquen, O.: Flows of dense granular media, Annu. Rev. Fluid Mech., 40, 1–24, https://doi.org/10.1146/annurev.fluid.40.111406.102142, 2008.
Foufoula-Georgiou, E., Ganti, V., and Dietrich, W.: A nonlocal theory of sediment transport on hillslopes, J. Geophys. Res.-Earth, 755, F00A16, https://doi.org/10.1029/2009JF001280, 2010.
Frey, P., and Church, M.: Bedload: a granular phenomenon, Earth Surf. Proc. Land., 36, 58–69, https://doi.org/10.1002/esp.2103, 2011.
Furbish, D. J.: Using the dynamically coupled behavior of land surface geometry and soil thickness in developing and testing hillslope evolution models, in: Prediction in Geomorphology, Geophysical Monograph Series, vol. 135, edited by: Wilcock P. and Iverson, R., American Geophysical Union, Washington, DC, 169–181, 2003.
Furbish, D. J. and Doane, T. H.: Rarefied particle motions on hillslopes – Part 4: Philosophy, Earth Surf. Dynam., 9, 629–664, https://doi.org/10.5194/esurf-9-629-2021, 2021.
Furbish, D. J. and Haff, P. K.: From divots to swales: Hillslope sediment transport across divers length scales, J. Geophys. Res.-Earth, 115, F03001, https://doi.org/10.1029/2009JF001576, 2010.
Furbish, D. J. and Roering, J. J.: Sediment disentrainment and the concept of local versus nonlocal transport on hillslopes, J. Geophys. Res.-Earth, 118, 1–16, https://doi.org/10.1002/jgrf.20071, 2013.
Furbish, D. J., Schmeeckle, M. W., and Roering, J. J.: Thermal and force-chain effects in an experimental, sloping granular shear flow, Earth Surf. Proc. Land., 33, 2108–2117, 2008.
Furbish, D. J., Haff, P. K., Dietrich, W. E., and Heimsath, A. M.: Statistical description of slope-dependent soil transport and the diffusion-like coefficient, J. Geophys. Res.-Earth, 114, F00A05, https://doi.org/10.1029/2009JF001267, 2009.
Furbish, D. J., Roseberry, J. C., and Schmeeckle, M. W.: A probabilistic description of the bed load sediment flux: 3. The particle velocity distribution and the diffusive flux, J. Geophys. Res.-Earth, 117, F03033, https://doi.org/10.1029/2012JF002355, 2012.
Furbish, D. J., Fathel, S. L., Schmeeckle, M. W., Jerolmack, D. J., and Schumer, R.: The elements and richness of particle diffusion during sediment transport at small timescales, Earth Surf. Proc. Land., 42, 214–237, https://doi.org/10.1002/esp.4084, 2017a.
Furbish, D. J., Fathel, S. L., and Schmeeckle, M. W.: Particle motions and bedload theory: The entrainment forms of the flux and the Exner equation, in: Gravel-Bed Rivers: Processes and Disasters, 1st Edn., edited by: Tsutsumi, D. and Laronne, J. B., John Wiley & Sons Ltd., available at: https://onlinelibrary.wiley.com/doi/book/10.1002/9781118971437 (last access: June 2021)), 2017b.
Furbish, D. J., Roering, J. J., Almond, P., and Doane, T. H.: Soil particle transport and mixing near a hillslope crest: 1. Particle ages and residence times, J. Geophys. Res.-Earth, 123, 1052–1077, https://doi.org/10.1029/2017JF004315, 2018a.
Furbish, D. J., Schumer, R., and Keen-Zebert, A.: The rarefied (non-continuum) conditions of tracer particle transport in soils, with implications for assessing the intensity and depth dependence of mixing from geochronology, Earth Surf. Dynam., 6, 1169–1202, https://doi.org/10.5194/esurf-6-1169-2018, 2018b.
Furbish, D. J., Williams, S. G. W., Roth, D. L., Doane, T. H., and Roering, J. J.: Rarefied particle motions on hillslopes – Part 2: Analysis, Earth Surf. Dynam., 9, 577–613, https://doi.org/10.5194/esurf-9-577-2021, 2021a.
Furbish, D. J., Williams, S. G. W., and Doane, T. H.: Rarefied particle motions on hillslopes – Part 3: Entropy, Earth Surf. Dynam., 9, 615–628, https://doi.org/10.5194/esurf-9-615-2021, 2021b.
Gabet, E. J.: Gopher bioturbation: Field evidence for non-linear hillslope diffusion, Earth Surf. Proc. Land., 25, 1419–1428, 2000.
Gabet, E. J.: Sediment transport by dry ravel, J. Geophys. Res.-Earth, 108, 2049, https://doi.org/10.1029/2001JB001686, 2003.
Gabet, E. J. and Mendoza, M. K.: Particle transport over rough hillslope surfaces by dry ravel: Experiments and simulations with implications for nonlocal sediment flux, J. Geophys. Res.-Earth, 117, F01019, https://doi.org/10.1029/2011JF002229, 2012.
Gabet, E. J., Reichman, O. J., and Seabloom, E. W.: The effects of bioturbation on soil processes and sediment transport, Annu. Rev. Earth Planet. Sci., 31, 249–273, 2003.
Gerber, E. and Scheidegger, A. E.: On the dynamics of scree slopes, Rock Mech., 6, 25–38, 1974.
Gibbs, J. W.: Elementary Principles in Statistical Mechanics, Yale University Press, New Haven, Connecticut, 1902.
Goldhirsch, I.: Introduction to granular temperature, Powder Technol., 182, 130–136, 2008.
Gunkelmann, N., Montaine, M., and Pöschel, T.: Stochastic behavior of the coefficient of normal restitution, Phys. Rev. E, 89, 022205, https://doi.org/10.1103/PhysRevE.89.022205, 2014.
Haff, P. K.: Grain flow as a fluid-mechanical phenomenon, J. Fluid Mech., 134, 401–430, 1983.
Henann, D. L. and Kamrin, K.: A predictive, size-dependent continuum model for dense granular flows, P. Natl. Acad. Sci. USA, 110, 6730–6735, 2013.
Hosking, J. R. M. and Wallis, J. R.: Parameter and quartile estimation for the generalized Pareto distribution, Technometrics, 29, 339–349, 1987.
Houssais, M. and Jerolmack, D. J.: Toward a unifying constitutive relation for sediment transport across environments, Geomorphology, 277, 251–264, https://doi.org/10.1016/j.geomorph.2016.03.026, 2017.
Houssais, M., Ortiz, C. P., Durian, D. J., and Jerolmack, D. J.: Onset of sediment transport is a continuous transition driven by fluid shear and granular creep, Nat. Commun., 6, 6527, https://doi.org/10.1038/ncomms7527, 2015.
Hunt, M. L., Zenit, R., Campbell, C. S., and Brennen, C. E.: Revisiting the 1954 suspension experiments of R. A. Bagnold, J. Fluid Mech., 452, 1–24, 2002.
Ismail, K. A. and Stronge, W. J.: Impact of viscoplastic bodies: Dissipation and restitution, J. Appl. Mech., 75, 061011, https://doi.org/10.1115/1.2965371, 2008.
Jaeger, H. M., Nagel, S. R., and Behringer, R. P.: Granular solids, liquids, and gases, Rev. Modern Phys., 68, 1259–1273, 1996.
Jaynes, E. T.: Information theory and statistical mechanics, Phys. Rev., 106, 620–630, 1957a.
Jaynes, E. T.: Information theory and statistical mechanics. II, Phys. Rev., 108, 171–190, 1957b.
Jenkins, J. T. and Savage, S. B.: A theory for the rapid flow of identical, smooth, nearly elastic, spherical particles, J. Fluid Mech., 130, 187–202, 1983.
Jerolmack, D. J. and Daniels, K. E.: Viewing Earth's surface as a soft-matter landscape, Nat. Rev. Phys., 1, 716–730, https://doi.org/10.1038/s42254-019-0111-x, 2019.
Kachuck, S. B. and Voth, G. A.: Simulations of granular gravitational collapse, Phys. Rev. E, 88, 062202, https://doi.org/10.1103/PhysRevE.88.062202, 2013.
Kirkby, M. J. and Statham, I.: Stone movement and scree formation, J. Geol., 83, 349–362, 1975.
Kumaran, V.: Kinematic model for sheared granular flows in the high Knudsen number limit, Phys. Rev. Lett., 95, 108001, https://doi.org/10.1103/PhysRevLett.95.108001, 2005.
Kumaran, V.: Granular flow of rough particles in the high-Knudsen-number limit, J. Fluid Mech., 561, 43–72, 2006.
Lamb, M. P., Scheingross, J. S., Amidon, W. H., Swanson, E., and Limaye, A.: A model for fire-induced sediment yield by dry ravel in steep landscapes, J. Geophys. Res.-Earth, 116, F03006, https://doi.org/10.1029/2010JF001878, 2011.
Lamb, M. P., Levina, M., DiBiase, R. A., and Fuller, B. M.: Sediment storage by vegetation in steep bedrock landscapes: Theory, experiments, and implications for postfire sediment yield, J. Geophys. Res.-Earth, 118, 1147–1160, https://doi.org/10.1002/jgrf.20058, 2013.
Lee, D. B. and Jerolmack, D.: Determining the scales of collective entrainment in collision-driven bed load, Earth Surf. Dynam., 6, 1089–1099, https://doi.org/10.5194/esurf-6-1089-2018, 2018.
Luckman, B. H.: Processes, Transport, Deposition, and Landforms: Rockfall, in: Treatise on Geomorphology, Vol. 7, edited by: Shroder, J. F., Academic Press, San Diego, 174–182, 2013.
Moore, H. J., Hutton, R. E., Clow, G. D., and Spitzer, C. R.: Physical properties of the surface materials at the Viking landing sites on Mars, US Geological Survey Professional Paper, US Geological Survey, United States Government Printing Office, Washington, https://doi.org/10.3133/pp1389, 1987.
Nakagawa, H. and Tsujimoto, T.: Sand bed instability due to bed load motion, J. Hydraul. Eng., 106, 2023–2051, 1980.
Pähtz, T. and Durán, O.: The cessation threshold of nonsuspended sediment transport across aeolian and fluvial environments, J. Geophys. Res.-Earth, 123, 1638–1666, https://doi.org/10.1029/2017JF004580, 2018.
Pickands, J.: Statistical inference using extreme order statistics, Ann. Statist., 3, 119–131, 1975.
Quartier, L., Andreotti, B., Douady, S., and Daerr, A.: Dynamics of a grain on a sandpile model, Phys. Rev. E, 62, 8299–8307, 2000.
Riguidel, F.-X., Hansen, A., and Bideau, D.: Gravity-driven motion of a particle on an inclined plane with controlled roughness, Europhys. Lett., 28, 13–18, 1994.
Risken, H.: The Fokker–Planck Equation: Methods of Solution and Applications, Springer, Berlin, 1984.
Risso, D. and Cordero, P.: Dynamics of rarefied granular gases, Phys. Rev. E, 65, 021304, https://doi.org/10.1103/PhysRevE.65.021304, 2002.
Roering, J. J.: Soil creep and convex-upward velocity profiles: theoretical and experimental investigation of disturbance-driven sediment transport on hillslopes, Earth Surf. Proc. Land., 29, 1597–1612, 2004.
Roering, J. J. and Gerber, M.: Fire and the evolution of steep, soil-mantled landscapes, Geology, 33, 349–352, https://doi.org/10.1130/G21260.1, 2005.
Roering, J. J., Kirchner, J. W., and Dietrich, W. E.: Evidence for nonlinear, diffusive sediment transport on hillslopes and implications for landscape morphology, Water Resour. Res., 35, 853–870, 1999.
Roering, J. J., Almond, P., Tonkin, P., and McKean, J.: Soil transport driven by biological processes over millenial time scales, Geology, 30, 1115–1118, 2002.
Roth, D. L., Doane, T. H., Roering, J. J., Furbish, D. J., and Zettler-Mann, A.: Particle motion on burned and vegetated hillslopes, P. Natl. Acad. Sci. USA, 117, 25335–25343, https://doi.org/10.1073/pnas.1922495117, 2020.
Samson, L., Ippolito, I., Batrouni, G. G., and Lemaitre, J.: Diffusive properties of motion on a bumpy plane, Eur. Phys. J. B, 3, 377–385, 1998.
Samson, L., Ippolito, I., Bideau, D., and Batrouni, G. G.: Motion of grains down a bumpy surface, Chaos, 9, 639–648, 1999.
Schumer, R., Baeumer, B., and Meerschaert, M. M.: Fractional advection-dispersion equations for modeling transport at the Earth surface, J. Geophys. Res.-Earth, 114, F00A07, https://doi.org/10.1029/2008JF001246, 2009.
Serero, D., Gunkelmann, N., and Pöschel, T.: Hydrodynamics of binary mixtures of granular gases with stochastic coefficient of restitution, J. Fluid Mech., 781, 595–621, 2015.
Statham, I.: A scree slope rockfall model, Earth Surf. Process., 1, 43–62, 1976.
Stronge, W. J.: Rigid body collisions with friction, P. Roy. Soc. Lond. A, 431, 169–181, 1990.
Stronge, W. J.: Impact Mechanics, Cambridge University Press, Cambridge, 2000.
Tajima, H. and Fujisawa, F.: Projectile trajectory of penguin's faeces and rectal pressure revisited, arXiv: preprint, arXiv:2007.00926 [physics.bio-ph], 2020.
Tesson, P. -A., Conway, S. J., Mangold, N., Ciazela, J., Lewis, S. R., and Mège, D.: Evidence for thermal-stress-induced rockfalls on Mars impact crater slopes, Icarus, 342, 113503, https://doi.org/10.1016/j.icarus.2019.113503, 2020.
Tsujimoto, T.: Probabilistic model of the process of bed load transport and its application to mobile-bed problems, PhD thesis, Kyoto University, Kyoto, Japan, 1978.
Tucker, G. E. and Bradley, D. N.: Trouble with diffusion: Reassessing hillslope erosion laws with a particle-based model, J. Geophys. Res.-Earth, 115, F00A10, https://doi.org/10.1029/2009JF001264, 2010.
van Zon, J. S., and MacKintosh, F. C.: Velocity distributions in dissipative granular gases, Phys. Rev. Lett., 93, 038001, https://doi.org/10.1103/PhysRevLett.93.038001, 2004.
Volfson, D., Meerson, B., and Tsimring, L. S.: Thermal collapse of a granular gas under gravity, Phys. Rev. E, 73, 061305, https://doi.org/10.1103/PhysRevE.73.061305, 2006.
von Smoluchowski M.: Zur kinetischen Theorie der Brownschen Molekularbewegung und der Suspensionen, Ann. Phys., 326, 756–780, 1906.
Yu, P., Schröter, M., and Sperl, M.: Velocity distribution of a homogeneously cooling granular gas, Phys. Rev. Lett., 124, 208007,
https://doi.org/10.1103/PhysRevLett.124.208007, 2020.
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Short summary
Sediment particles skitter down steep hillslopes on Earth and Mars. Particles gain speed in going downhill but are slowed down and sometimes stop due to collisions with the rough surface. The likelihood of stopping depends on the energetics of speeding up (heating) versus slowing down (cooling). Statistical physics predicts that particle travel distances are described by a generalized Pareto distribution whose form varies with the Kirkby number – the ratio of heating to cooling.
Sediment particles skitter down steep hillslopes on Earth and Mars. Particles gain speed in...
