Articles | Volume 9, issue 2
https://doi.org/10.5194/esurf-9-167-2021
© 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-9-167-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Mar 2021
Research article |
| 09 Mar 2021
| 09 Mar 2021
Growing topography due to contrasting rock types in a tectonically dead landscape
School of Geographical and Earth Sciences, University of Glasgow,
Glasgow, G12 8QQ, UK
CAPES Foundation, Ministry of Education of Brazil, Brasília, DF 70040-020, Brazil
Cristina Persano
School of Geographical and Earth Sciences, University of Glasgow,
Glasgow, G12 8QQ, UK
Martin D. Hurst
School of Geographical and Earth Sciences, University of Glasgow,
Glasgow, G12 8QQ, UK
Paul Bishop
School of Geographical and Earth Sciences, University of Glasgow,
Glasgow, G12 8QQ, UK
Derek Fabel
Scottish Universities Environmental Research Centre, East Kilbride,
G75 0QF, UK
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Boris Gailleton, Simon M. Mudd, Fiona J. Clubb, Daniel Peifer, and Martin D. Hurst
Earth Surf. Dynam., 7, 211–230, https://doi.org/10.5194/esurf-7-211-2019, https://doi.org/10.5194/esurf-7-211-2019, 2019
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The shape of landscapes is influenced by climate changes, faulting or the nature of the rocks under the surface. One of the most sensitive parts of the landscape to these changes is the river system that eventually adapts to such changes by adapting its slope, the most extreme example being a waterfall. We here present an algorithm that extracts changes in river slope over large areas from satellite data with the aim of investigating climatic, tectonic or geologic changes in the landscape.
Jörg Christian Robl, Fabian Dremel, Kurt Stüwe, Stefan Hergarten, Christoph von Hagke, and Derek Fabel
EGUsphere, https://doi.org/10.5194/egusphere-2024-3256, https://doi.org/10.5194/egusphere-2024-3256, 2024
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The Bohemian Massif is one of several low mountain ranges in Europe, which rises more than 1 km above the surrounding lowlands. Landscape characteristics indicate relief rejuvenation due to recent surface uplift. To constrain the pace of relief formation we determined erosion rates of 20 catchments that range from 22 to 51 m per million years. Correlating these rates with topographic properties reveals that contrasts in bedrock erodibility represent a critical control of landscape evolution.
Jennifer R. Shadrick, Dylan H. Rood, Martin D. Hurst, Matthew D. Piggott, Klaus M. Wilcken, and Alexander J. Seal
Earth Surf. Dynam., 11, 429–450, https://doi.org/10.5194/esurf-11-429-2023, https://doi.org/10.5194/esurf-11-429-2023, 2023
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This study uses a coastal evolution model to interpret cosmogenic beryllium-10 concentrations and topographic data and, in turn, quantify long-term cliff retreat rates for four chalk sites on the south coast of England. By using a process-based model, clear distinctions between intertidal weathering rates have been recognised between chalk and sandstone rock coast sites, advocating the use of process-based models to interpret the long-term behaviour of rock coasts.
Tancrède P. M. Leger, Andrew S. Hein, Ángel Rodés, Robert G. Bingham, Irene Schimmelpfennig, Derek Fabel, Pablo Tapia, and ASTER Team
Clim. Past, 19, 35–59, https://doi.org/10.5194/cp-19-35-2023, https://doi.org/10.5194/cp-19-35-2023, 2023
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Over the past 800 thousand years, variations in the Earth’s orbit and tilt have caused antiphased solar insolation intensity in the Northern and Southern Hemispheres. Paradoxically, glacial records suggest that global ice sheets have responded synchronously to major cold glacial and warm interglacial episodes. To address this puzzle, we present a new detailed glacier chronology that estimates the timing of multiple Patagonian ice-sheet waxing and waning cycles over the past 300 thousand years.
Jennifer R. Shadrick, Martin D. Hurst, Matthew D. Piggott, Bethany G. Hebditch, Alexander J. Seal, Klaus M. Wilcken, and Dylan H. Rood
Earth Surf. Dynam., 9, 1505–1529, https://doi.org/10.5194/esurf-9-1505-2021, https://doi.org/10.5194/esurf-9-1505-2021, 2021
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Here we use topographic and 10Be concentration data to optimise a coastal evolution model. Cliff retreat rates are calculated for two UK sites for the past 8000 years and, for the first time, highlight a strong link between the rate of sea level rise and long-term cliff retreat rates. This method enables us to study past cliff response to sea level rise and so to greatly improve forecasts of future responses to accelerations in sea level rise that will result from climate change.
Boris Gailleton, Simon M. Mudd, Fiona J. Clubb, Daniel Peifer, and Martin D. Hurst
Earth Surf. Dynam., 7, 211–230, https://doi.org/10.5194/esurf-7-211-2019, https://doi.org/10.5194/esurf-7-211-2019, 2019
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The shape of landscapes is influenced by climate changes, faulting or the nature of the rocks under the surface. One of the most sensitive parts of the landscape to these changes is the river system that eventually adapts to such changes by adapting its slope, the most extreme example being a waterfall. We here present an algorithm that extracts changes in river slope over large areas from satellite data with the aim of investigating climatic, tectonic or geologic changes in the landscape.
Andres Payo, Bismarck Jigena Antelo, Martin Hurst, Monica Palaseanu-Lovejoy, Chris Williams, Gareth Jenkins, Kathryn Lee, David Favis-Mortlock, Andrew Barkwith, and Michael A. Ellis
Geosci. Model Dev., 11, 4317–4337, https://doi.org/10.5194/gmd-11-4317-2018, https://doi.org/10.5194/gmd-11-4317-2018, 2018
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We describe a new algorithm that automatically delineates the cliff top and toe of a cliffed coastline from a digital elevation model (DEM). The algorithm builds upon existing methods but is specifically designed to resolve very irregular planform coastlines with many bays and capes, such as parts of the coastline of Great Britain.
Simon M. Mudd, Fiona J. Clubb, Boris Gailleton, and Martin D. Hurst
Earth Surf. Dynam., 6, 505–523, https://doi.org/10.5194/esurf-6-505-2018, https://doi.org/10.5194/esurf-6-505-2018, 2018
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Rivers can reveal information about erosion rates, tectonics, and climate. In order to make meaningful inferences about these influences, one must be able to compare headwaters to downstream parts of the river network. We describe new methods for normalizing river steepness for drainage area to better understand how rivers record erosion rates in eroding landscapes.
Andrés Payo, David Favis-Mortlock, Mark Dickson, Jim W. Hall, Martin D. Hurst, Mike J. A. Walkden, Ian Townend, Matthew C. Ives, Robert J. Nicholls, and Michael A. Ellis
Geosci. Model Dev., 10, 2715–2740, https://doi.org/10.5194/gmd-10-2715-2017, https://doi.org/10.5194/gmd-10-2715-2017, 2017
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CoastalME is a generic modelling environment to simulate coastal landscape evolution on spatial scales of kms to tens of kms, over decadal to centennial timescales. The novelty is that it simulates coastal morphology evolution as a set of dynamically linked raster and geometrical objects. Geometrical objects are derived from the raster structure providing a library of coastal elements (e.g. shoreline) that are conventionally used for modelling coastal behaviour on the timescales of interest.
Fiona J. Clubb, Simon M. Mudd, David T. Milodowski, Declan A. Valters, Louise J. Slater, Martin D. Hurst, and Ajay B. Limaye
Earth Surf. Dynam., 5, 369–385, https://doi.org/10.5194/esurf-5-369-2017, https://doi.org/10.5194/esurf-5-369-2017, 2017
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Floodplains and fluvial terraces can provide information about current and past river systems, helping to reveal how channels respond to changes in both climate and tectonics. We present a new method of identifying these features objectively from digital elevation models by analysing their slope and elevation compared to the modern river. We test our method in eight field sites, and find that it provides rapid and reliable extraction of floodplains and terraces across a range of landscapes.
Martin D. Hurst, Dylan H. Rood, and Michael A. Ellis
Earth Surf. Dynam., 5, 67–84, https://doi.org/10.5194/esurf-5-67-2017, https://doi.org/10.5194/esurf-5-67-2017, 2017
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Beryllium-10 is a rare isotope that only forms near to the Earth surface, allowing rock surfaces to be dated. In this paper we develop a numerical model for the evolution of shore platforms and associated 10Be concentrations to explore the potential for this method to reveal long-term rates of sea cliff retreat. Tides, sea level, cliffs and beaches all modify how rapidly 10Be accumulates on the shore platform, but there is great potential to measure rates of cliff retreat and platform erosion.
Christopher W. Thomas, A. Brad Murray, Andrew D. Ashton, Martin D. Hurst, Andrew K. A. P. Barkwith, and Michael A. Ellis
Earth Surf. Dynam., 4, 871–884, https://doi.org/10.5194/esurf-4-871-2016, https://doi.org/10.5194/esurf-4-871-2016, 2016
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Complex sandy coastlines, such as capes and spits, are important socio-economically while underpinning and protecting important natural habitats. Although they may protect inshore areas, they are inherently fragile and susceptible to erosion. We have explored how spits and capes might adapt to changing wave climate through modelling. We find that coastlines may not be in equilibrium with current conditions, and past shapes may strongly influence those adapting to new wave climates.
Simon Marius Mudd, Marie-Alice Harel, Martin D. Hurst, Stuart W. D. Grieve, and Shasta M. Marrero
Earth Surf. Dynam., 4, 655–674, https://doi.org/10.5194/esurf-4-655-2016, https://doi.org/10.5194/esurf-4-655-2016, 2016
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Cosmogenic nuclide concentrations are widely used to calculate catchment-averaged denudation rates. Despite their widespread use, there is currently no open source method for calculating such rates, and the methods used to calculate catchment-averaged denudation rates vary widely between studies. Here we present an automated, open-source method for calculating basin averaged denudation rates, which may be used as a stand-alone calculator or as a front end to popular online calculators.
M. Attal, S. M. Mudd, M. D. Hurst, B. Weinman, K. Yoo, and M. Naylor
Earth Surf. Dynam., 3, 201–222, https://doi.org/10.5194/esurf-3-201-2015, https://doi.org/10.5194/esurf-3-201-2015, 2015
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Steeper landscapes tend to erode faster. In this study, we also find that sediment produced on steeper landscapes is coarser. Soils are coarser because fragments spend less time in the soil so are less exposed to processes that can break them down. Change in sediment sources impact the sediment transported by rivers: rivers transport sediment up to cobble size in low-slope, soil-mantled areas; they transport much coarser sediment (including boulders supplied from landslides) in the steep areas.
B. W. Goodfellow, A. P. Stroeven, D. Fabel, O. Fredin, M.-H. Derron, R. Bintanja, and M. W. Caffee
Earth Surf. Dynam., 2, 383–401, https://doi.org/10.5194/esurf-2-383-2014, https://doi.org/10.5194/esurf-2-383-2014, 2014
A. Barkwith, M. D. Hurst, C. W. Thomas, M. A. Ellis, P. L. Limber, and A. B. Murray
Earth Surf. Dynam., 2, 233–242, https://doi.org/10.5194/esurf-2-233-2014, https://doi.org/10.5194/esurf-2-233-2014, 2014
M. D. Hurst, M. A. Ellis, K. R. Royse, K. A. Lee, and K. Freeborough
Earth Surf. Dynam., 1, 67–78, https://doi.org/10.5194/esurf-1-67-2013, https://doi.org/10.5194/esurf-1-67-2013, 2013
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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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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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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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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.
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.
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Short summary
Plate tectonics drive the formation of mountain ranges. Yet when tectonic forces cease, mountain ranges persist for hundreds of millions of years, forming major Earth surface features. This work presents denudation rate estimates from one such ancient mountain range that show that denudation is strongly tied to rock type. Resistant rocks denude more slowly despite having much steeper topography, and contrasts in rock type cause increasing relief in the absence of active tectonics.
Plate tectonics drive the formation of mountain ranges. Yet when tectonic forces cease, mountain...
