Articles | Volume 9, issue 5
Research article 07 Oct 2021
Research article | 07 Oct 2021
Sediment shell-content diminishes current-driven sand ripple development and migration
Chiu H. Cheng et al.
No articles found.
Seyedabdolhossein Mehvar, Kathelijne Wijnberg, Bas Borsje, Norman Kerle, Jan Maarten Schraagen, Joanne Vinke-de Kruijf, Karst Geurs, Andreas Hartmann, Rick Hogeboom, and Suzanne Hulscher
Nat. Hazards Earth Syst. Sci., 21, 1383–1407,Short summary
This review synthesizes and complements existing knowledge in designing resilient vital infrastructure systems (VIS). Results from a systematic literature review indicate that (i) VIS are still being built without taking resilience explicitly into account and (ii) measures to enhance the resilience of VIS have not been widely applied in practice. The main pressing topic to address is the integration of the combined social, ecological, and technical resilience of these systems.
Emil De Borger, Justin Tiano, Ulrike Braeckman, Adriaan D. Rijnsdorp, and Karline Soetaert
Biogeosciences, 18, 2539–2557,Short summary
Bottom trawling alters benthic mineralization: the recycling of organic material (OM) to free nutrients. To better understand how this occurs, trawling events were added to a model of seafloor OM recycling. Results show that bottom trawling reduces OM and free nutrients in sediments through direct removal thereof and of fauna which transport OM to deeper sediment layers protected from fishing. Our results support temporospatial trawl restrictions to allow key sediment functions to recover.
Ringo Ossewaarde, Tatiana Filatova, Yola Georgiadou, Andreas Hartmann, Gül Özerol, Karin Pfeffer, Peter Stegmaier, Rene Torenvlied, Mascha van der Voort, Jord Warmink, and Bas Borsje
Nat. Hazards Earth Syst. Sci., 21, 1119–1133,Short summary
The aim of this paper is to review and structure current developments in resilience research in the field of climate change studies, in terms of the approaches, definitions, models, and commitments that are typical for naturalist and constructivist research and propose a research agenda of topics distilled from current developments in resilience research.
Alice E. Webb, Didier M. de Bakker, Karline Soetaert, Tamara da Costa, Steven M. A. C. van Heuven, Fleur C. van Duyl, Gert-Jan Reichart, and Lennart J. de Nooijer
Revised manuscript accepted for BGShort summary
The biogeochemical behavior of shallow reef communities is quantified to better understand the impact of habitat degradation and species composition shifts on reef functioning. The reef communities investigated here barely support reef functions that are usually ascribed to conventional coral reefs and the overall biogeochemical behavior is found to be similar regardless of substrate type. This suggests a decrease in functional diversity which may therefore limit services provided by this reef.
Zhan Hu, Pim W. J. M. Willemsen, Bas W. Borsje, Chen Wang, Heng Wang, Daphne van der Wal, Zhenchang Zhu, Bas Oteman, Vincent Vuik, Ben Evans, Iris Möller, Jean-Philippe Belliard, Alexander Van Braeckel, Stijn Temmerman, and Tjeerd J. Bouma
Earth Syst. Sci. Data, 13, 405–416,Short summary
Erosion and accretion processes govern the ecogeomorphic evolution of intertidal (salt marsh and tidal flat) ecosystems and hence substantially affect their valuable ecosystem services. By applying a novel sensor, we obtained unique high-resolution daily bed-level change datasets from 10 marsh–mudflat sites in northwestern Europe. This dataset has revealed diverse spatial bed-level change patterns over daily to seasonal scales, which are valuable to theoretical and model development.
Long Jiang, Theo Gerkema, Jacco C. Kromkamp, Daphne van der Wal, Pedro Manuel Carrasco De La Cruz, and Karline Soetaert
Biogeosciences, 17, 4135–4152,Short summary
A seaward increasing chlorophyll-a gradient is observed during the spring bloom in a Dutch tidal bay. Biophysical model runs indicate the roles of bivalve grazing and tidal import in shaping the gradient. Five common spatial phytoplankton patterns are summarized in global estuarine–coastal ecosystems: seaward increasing, seaward decreasing, concave with a chlorophyll maximum, weak spatial gradients, and irregular patterns.
Filipe Galiforni-Silva, Kathelijne M. Wijnberg, and Suzanne J. M. H. Hulscher
Earth Surf. Dynam., 8, 335–350,Short summary
Storm surges are often related to coastal dune erosion. We found that, for specific coastal settings, storm surges may enhance dune growth rather than only undermine it. Using a computer model and elevation data, we noticed that storm surges could deposit sand onto the sand flat from sand previously deposited closer to the sea. As they move to areas farther from the sea, it becomes easier for the wind to move this sand to the dunes. These findings may help coastal managers and policymakers.
Emil De Borger, Justin Tiano, Ulrike Braeckman, Tom Ysebaert, and Karline Soetaert
Biogeosciences, 17, 1701–1715,Short summary
By applying a novel technique to quantify organism-induced sediment–water column fluid exchange (bioirrigation), we show that organisms in subtidal (permanently submerged) areas have similar bioirrigation rates as those that inhabit intertidal areas (not permanently submerged), but organisms in the latter irrigate deeper burrows in this study. Our results expand on traditional methods to quantify bioirrigation rates and broaden the pool of field measurements of bioirrigation rates.
Long Jiang, Theo Gerkema, Déborah Idier, Aimée B. A. Slangen, and Karline Soetaert
Ocean Sci., 16, 307–321,Short summary
A model downscaling approach is used to investigate the effects of sea-level rise (SLR) on local tides. Results indicate that SLR induces larger increases in tidal amplitude and stronger nonlinear tidal distortion in the bay compared to the adjacent shelf sea. SLR can also change shallow-water tidal asymmetry and influence the direction and magnitude of bed-load sediment transport. The model downscaling approach is widely applicable for local SLR projections in estuaries and coastal bays.
Anouk Bomers, Ralph M. J. Schielen, and Suzanne J. M. H. Hulscher
Nat. Hazards Earth Syst. Sci., 19, 1895–1908,Short summary
Flood frequency curves are usually highly uncertain since they are based on short data sets of measured discharges or weather conditions. To decrease the confidence intervals, an efficient bootstrap method is developed. With this method, the data set of measured discharges of the Rhine river is extended by approximately 600 years. The study shows that historic flood events decrease the confidence interval of the flood frequency curve significantly, specifically in the range of large floods.
Koen D. Berends, Menno W. Straatsma, Jord J. Warmink, and Suzanne J. M. H. Hulscher
Nat. Hazards Earth Syst. Sci., 19, 1737–1753,Short summary
River flooding is a major safety concern. Sophisticated models are used to design ways to decrease flood risk, but until recently it was not feasible to calculate how uncertain these model predictions are. Using a new approach, we have now quantified the uncertainty of 12 interventions along the River Waal. Results show significant but not problematically high uncertainty. We demonstrate that the choice between interventions can be different when uncertainty is taken into account.
Filipe Galiforni Silva, Kathelijne M. Wijnberg, and Suzanne J. M. H. Hulscher
Earth Surf. Dynam. Discuss.,
Preprint withdrawnShort summary
Storms are often related to coastal dune erosion. We found that, for specific coastal settings, storms may enhance dune growth rather than only undermine it. Using a computer model and long-term monitoring data, we see that storms may bring sand from areas that are frequently inundated to areas that are often above the water. When above the water, this sand can be more easily transported by the wind and deposited on the dunes. These findings may help coastal managers and policymakers.
Tom J. S. Cox, Justus E. E. van Beusekom, and Karline Soetaert
Biogeosciences, 14, 5271–5280,Short summary
Photosynthesis by phytoplankton is a key source of oxygen (O2) in aquatic systems. We have developed a mathematical technique to calculate the rate of photosynthesis from time series of O2. Additionally, the approach leads to a better understanding of the influence on O2 measurements of the tides in coasts and estuaries. The results are important for correctly interpreting the data that are gathered by a growing set of continuous O2 sensors that are deployed around the world.
L. Meire, D. H. Søgaard, J. Mortensen, F. J. R. Meysman, K. Soetaert, K. E. Arendt, T. Juul-Pedersen, M. E. Blicher, and S. Rysgaard
Biogeosciences, 12, 2347–2363,Short summary
The Greenland Ice Sheet releases large amounts of freshwater, which strongly influences the biogeochemistry of the adjacent fjord systems and continental shelves. Here we present seasonal observations of the carbonate system in the surface waters of a west Greenland tidewater outlet glacier fjord. Our data reveal a permanent undersaturation of CO2 in the surface layer of the entire fjord and adjacent shelf, creating a high annual uptake of 65gCm-2yr-1.
L. Pozzato, D. Van Oevelen, L. Moodley, K. Soetaert, and J. J. Middelburg
Biogeosciences, 10, 6879–6891,
L. Meire, K. E. R. Soetaert, and F. J. R. Meysman
Biogeosciences, 10, 2633–2653,
A. de Kluijver, K. Soetaert, J. Czerny, K. G. Schulz, T. Boxhammer, U. Riebesell, and J. J. Middelburg
Biogeosciences, 10, 1425–1440,
K. Soetaert, D. van Oevelen, and S. Sommer
Biogeosciences, 9, 5341–5352,
Related subject area
Physical: Geomorphology (including all aspects of fluvial, coastal, aeolian, hillslope and glacial geomorphology)Triggering and propagation of exogenous sediment pulses in mountain channels: insights from flume experiments with seismic monitoringTemporal changes in the debris flow threshold under the effects of ground freezing and sediment storage on Mt. FujiSedimentary architecture and landforms of the late Saalian (MIS 6) ice sheet margin offshore of the NetherlandsRelationship between meteoric 10Be and NO3− concentrations in soils along Shackleton Glacier, AntarcticaSand mining far outpaces natural supply in a large alluvial riverThe formation and geometry characteristics of boulder bars due to outburst floods triggered by overtopped landslide dam failureLandslide-lake outburst floods accelerate downstream hillslope slippageThe relative influence of dune aspect ratio and beach width on dune erosion as a function of storm duration and surge levelA temperature-dependent mechanical model to assess the stability of degrading permafrost rock slopesThe effects of storms and a transient sandy veneer on the interannual planform evolution of a low-relief coastal cliff and shore platform at Sargent Beach, Texas, USAIdentification of rock and fracture kinematics in high alpine rockwalls under the influence of elevationControls on the grain size distribution of landslides in Taiwan: the influence of drop height, scar depth and bedrock strengthAssessing the effect of topography on Cs-137 concentrations within forested soils due to the Fukushima Daiichi Nuclear Power Plant accident, JapanClimatic controls on mountain glacier basal thermal regimes dictate spatial patterns of glacial erosionTectonically and climatically driven mountain-hopping erosion in central Guatemala from detrital 10Be and river profile analysisStochastic alluvial fan and terrace formation triggered by a high-magnitude Holocene landslide in the Klados Gorge, CreteControls on the rates and products of particle attrition by bed-load collisionsBedrock river erosion through dipping layered rocks: quantifying erodibility through kinematic wave speedParticle energy partitioning and transverse diffusion during rarefied travel on an experimental hillslopeMulti-objective optimisation of a rock coast evolution model with cosmogenic 10Be analysis for the quantification of long-term cliff retreat ratesShort communication: Runout of rock avalanches limited by basal friction but controlled by fragmentationRarefied particle motions on hillslopes – Part 1: TheoryRarefied particle motions on hillslopes – Part 2: AnalysisRarefied particle motions on hillslopes – Part 3: EntropyRarefied particle motions on hillslopes – Part 4: PhilosophyImplications of the ongoing rock uplift in NW Himalayan interiorsInteractions between deforestation, landscape rejuvenation, and shallow landslides in the North Tanganyika–Kivu rift region, AfricaRelevance of acoustic methods to quantify bedload transport and bedform dynamics in a large sandy-gravel-bed riverEarthquake-induced debris flows at Popocatépetl Volcano, MexicoControls on the hydraulic geometry of alluvial channels: bank stability to gravitational failure, the critical-flow hypothesis, and conservation of mass and energyEffect of stress history on sediment transport and channel adjustment in graded gravel-bed riversHack distributions of rill networks and nonlinear slope length–soil loss relationshipsDevelopment of smart boulders to monitor mass movements via the Internet of Things: a pilot study in NepalLaboratory observations on meltwater meandering rivulets on iceQuantifying thresholds of barrier geomorphic change in a cross-shore sediment-partitioning modelThe enigma of relict large sorted stone stripes in the tropical Ethiopian HighlandsGrowing topography due to contrasting rock types in a tectonically dead landscapeBreaking down chipping and fragmentation in sediment transport: the control of material strengthHow do modeling choices and erosion zone locations impact the representation of connectivity and the dynamics of suspended sediments in a multi-source soil erosion model?Different coastal marsh sites reflect similar topographic conditions under which bare patches and vegetation recovery occurCoupling threshold theory and satellite-derived channel width to estimate the formative discharge of Himalayan foreland riversInertial drag and lift forces for coarse grains on rough alluvial beds measured using in-grain accelerometersGERALDINE (Google Earth Engine supRaglAciaL Debris INput dEtector): a new tool for identifying and monitoring supraglacial landslide inputsShort communication: Multiscalar roughness length decomposition in fluvial systems using a transform-roughness correlation (TRC) approachEvolution of events before and after the 17 June 2017 rock avalanche at Karrat Fjord, West Greenland – a multidisciplinary approach to detecting and locating unstable rock slopes in a remote Arctic areaComplementing scale experiments of rivers and estuaries with numerically modelled hydrodynamicsCharacterization of morphological units in a small, forested stream using close-range remotely piloted aircraft imageryTopographic controls on divide migration, stream capture, and diversification in riverine lifeIce sheet and palaeoclimate controls on drainage network evolution: an example from Dogger Bank, North SeaExperimental study of sediment supply control on step formation, evolution, and stability
Marco Piantini, Florent Gimbert, Hervé Bellot, and Alain Recking
Earth Surf. Dynam., 9, 1423–1439,Short summary
We carry out laboratory experiments to investigate the formation and propagation dynamics of exogenous sediment pulses in mountain rivers. We show that the ability of a self-formed deposit to destabilize and generate sediment pulses depends on the sand content of the mixture, while each pulse turns out to be formed by a front, a body, and a tail. Seismic measurements reveal a complex and non-unique dependency between seismic power and sediment pulse transport characteristics.
Fumitoshi Imaizumi, Atsushi Ikeda, Kazuki Yamamoto, and Okihiro Ohsaka
Earth Surf. Dynam., 9, 1381–1398,Short summary
The rainfall threshold for debris flow occurrence was evaluated on Mt. Fuji, Japan. Debris flows during frozen periods were triggered by a smaller magnitude of rainfall than during unfrozen periods. During unfrozen periods, the threshold of maximum hourly rainfall intensity triggering debris flow was higher when the volume of channel deposits was larger. The results suggest that the occurrence of frozen ground needs to be monitored for better debris flow disaster mitigation in cold regions.
Víctor Cartelle, Natasha L. M. Barlow, David M. Hodgson, Freek S. Busschers, Kim M. Cohen, Bart M. L. Meijninger, and Wessel P. van Kesteren
Earth Surf. Dynam., 9, 1399–1421,Short summary
Reconstructing the growth and decay of past ice sheets is critical to understand relationships between global climate and sea-level change. We take advantage of large wind-farm datasets in the southern North Sea to investigate buried landscapes left by ice sheet advance and retreat occurring about 160 000 years ago. We demonstrate the utility of offshore wind-farm data in refining palaeo-ice sheet margin limits and providing insight into the processes influencing marginal ice sheet dynamics.
Melisa A. Diaz, Lee B. Corbett, Paul R. Bierman, Byron J. Adams, Diana H. Wall, Ian D. Hogg, Noah Fierer, and W. Berry Lyons
Earth Surf. Dynam., 9, 1363–1380,Short summary
We collected soil surface samples and depth profiles every 5 cm (up to 30 cm) from 11 ice-free areas along the Shackleton Glacier, a major outlet glacier of the East Antarctic Ice Sheet (EAIS), and measured meteoric beryllium-10 and nitrate concentrations to understand the relationship between salts and beryllium-10. This relationship can help inform wetting history, landscape disturbance, and exposure duration.
Christopher R. Hackney, Grigorios Vasilopoulos, Sokchhay Heng, Vasudha Darbari, Samuel Walker, and Daniel R. Parsons
Earth Surf. Dynam., 9, 1323–1334,Short summary
Unsustainable sand mining poses a threat to the stability of river channels. We use satellite imagery to estimate volumes of material removed from the Mekong River, Cambodia, over the period 2016–2020. We demonstrate that current rates of extraction now exceed previous estimates for the entire Mekong Basin and significantly exceed the volume of sand naturally transported by the river. Our work highlights the importance of satellite imagery in monitoring sand mining activity over large areas.
Xiangang Jiang, Haiguang Cheng, Lei Gao, and Weiming Liu
Earth Surf. Dynam., 9, 1263–1277,Short summary
Boulder bars are a common form of riverbed morphology which can be affected by outburst flood. However, few studies have focused on boulder bars' formation process and development characteristics during landslide dam failure. In this paper, eight groups of dam failure experiments were carried out to study the development and geometry characteristics of boulder bars during and after dam failure. Moreover, the relationships between geometry parameters of boulder bars are investigated.
Wentao Yang, Jian Fang, and Jing Liu-Zeng
Earth Surf. Dynam., 9, 1251–1262,Short summary
The eastern Tibetan Plateau is an ideal place to study interactions among different geomorphic drivers. We report the impacts of two 2018 landslide-lake outburst floods up to 100 km distance downstream of the Jinsha River. By using remote sensing images, we found that the 2018 floods caused many hillslopes to slump during the prolonged period afterwards. The finding could help us to obtain a holistic picture of LLF impacts and improve geomorphic models of landscape evolution.
Michael Itzkin, Laura J. Moore, Peter Ruggiero, Sally D. Hacker, and Reuben G. Biel
Earth Surf. Dynam., 9, 1223–1237,Short summary
Studies of the impact of storms on dunes typically focus on the importance of dune elevation, here we analyze the protective services offered by the dune height and width, the morphology of the beach fronting the dune, and artificial dune construction via the use of sand fences. We find that dune volume loss most strongly correlates to beach width rather than dune shape, although when beach width is controlled for low and wide dunes offer greater protection than tall and narrow dunes.
Philipp Mamot, Samuel Weber, Saskia Eppinger, and Michael Krautblatter
Earth Surf. Dynam., 9, 1125–1151,Short summary
The mechanical response of permafrost degradation on high-mountain rock slope stability has not been calculated in a numerical model yet. We present the first approach for a model with thermal and mechanical input data derived from laboratory and field work, and existing concepts. This is applied to a test site at the Zugspitze, Germany. A numerical sensitivity analysis provides the first critical stability thresholds related to the rock temperature, slope angle and fracture network orientation.
Rose V. Palermo, Anastasia Piliouras, Travis E. Swanson, Andrew D. Ashton, and David Mohrig
Earth Surf. Dynam., 9, 1111–1123,Short summary
At Sargent Beach, Texas, USA, a rapidly eroding soft-sediment cliff system, we study the planform evolution of the cliff face in response to storms and sediment cover. Through this analysis, we characterize the feedbacks between morphology and retreat rate of a cliff face. We find that after a storm event, the roughness and sinuosity of the cliff face increase, which sustains higher retreat rates for years following.
Earth Surf. Dynam., 9, 977–994,Short summary
Alpine rockwalls are affected by weathering processes that result in rock and fracture deformation. This deformation decreases rockwall stability with time. I installed crackmeters along a topographic gradient to identify the spatial and temporal variation of weathering processes. My data show that elevation-dependent snow cover, topographic factors and fracture dipping control the frequency and magnitude of weathering processes and resulting rock kinematics.
Odin Marc, Jens M. Turowski, and Patrick Meunier
Earth Surf. Dynam., 9, 995–1011,Short summary
The size of grains delivered to rivers is an essential parameter for understanding erosion and sediment transport and their related hazards. In mountains, landslides deliver these rock fragments, but few studies have analyzed the landslide properties that control the resulting sizes. We present measurements on 17 landslides from Taiwan and show that their grain sizes depend on rock strength, landslide depth and drop height, thereby validating and updating a previous theory on fragmentation.
Misa Yasumiishi, Taku Nishimura, Jared Aldstadt, Sean J. Bennett, and Thomas Bittner
Earth Surf. Dynam., 9, 861–893,Short summary
Topographic effects on radioactive contamination in a forested area were quantitatively examined using soil core samples collected in a village in Fukushima, Japan. The results confirmed that local topography influences the contamination patterns in soils, and its effects vary depending on the combinations of the topographic parameters. This finding suggests that topographic characteristics should be considered carefully in future environmental radioactive risk assessments.
Jingtao Lai and Alison M. Anders
Earth Surf. Dynam., 9, 845–859,Short summary
Glaciers are strong erosive agents, and they have created many unique landforms in mountain belts. Climate has been viewed as a primary control on glacial erosion, yet our understanding of the mechanism by which climate impacts glacial erosion remains limited. Using computer simulations, we find that climate controls glacial erosion by modulating the temperature of the basal ice. Our results suggest that a warm and/or wet climate can create warm basal ice and, therefore, enhance erosion.
Gilles Brocard, Jane Kathrin Willenbring, Tristan Salles, Michael Cosca, Axel Guttiérez-Orrego, Noé Cacao Chiquín, Sergio Morán-Ical, and Christian Teyssier
Earth Surf. Dynam., 9, 795–822,Short summary
The rise of a mountain affects the circulation of water, both in the atmosphere and over the land surface, thereby affecting the erosion of the land surface. We document how the rise of a mountain in central Guatemala has affected the erosion of an older range nearby. The new range intercepts precipitation formerly delivered to the older range. River response to the uplift of the new range has decreased incision across the older one. Both have reduced hillslope erosion over the old range.
Elena T. Bruni, Richard F. Ott, Vincenzo Picotti, Negar Haghipour, Karl W. Wegmann, and Sean F. Gallen
Earth Surf. Dynam., 9, 771–793,Short summary
The Klados River catchment contains seemingly overlarge, well-preserved alluvial terraces and fans. Unlike previous studies, we argue that the deposits formed in the Holocene based on their position relative to a paleoshoreline uplifted in 365 CE and seven radiocarbon dates. We also find that constant sediment supply from high-lying landslide deposits disconnected the valley from regional tectonics and climate controls, which resulted in fan and terrace formation guided by stochastic events.
Kimberly Litwin Miller and Douglas Jerolmack
Earth Surf. Dynam., 9, 755–770,Short summary
We conducted experiments to investigate the mechanics of sediment attrition due to collisions with the channel bed during downstream transport. During this process, the grains become rounder and smaller, changing the overall distribution of sediment in the river. In this work we examine how material properties play a role in the breakdown of sediment due to energetic collisions and the fine particles that are produced when chipped off of larger grains.
Nate A. Mitchell and Brian J. Yanites
Earth Surf. Dynam., 9, 723–753,Short summary
A landscape's appearance reflects the properties of the underlying bedrock. For example, strong bedrock can lead to steep slopes. Recent work has shown, however, that in areas with mixed rock types the stronger bedrock can have lower slopes. In this study, we use numerical models of bedrock river erosion to show why this change in behavior occurs. We also present a new approach for estimating bedrock erodibility. This new approach can allow for new opportunities in the field of geomorphology.
Sarah G. W. Williams and David J. Furbish
Earth Surf. Dynam., 9, 701–721,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.
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. Discuss.,
Revised manuscript accepted for ESurfShort summary
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.
Øystein T. Haug, Matthias Rosenau, Michael Rudolf, Karen Leever, and Onno Oncken
Earth Surf. Dynam., 9, 665–672,Short summary
The runout of rock avalanches scales with their volume but also shows a considerable variation for avalanches with similar volumes. Here we show that besides size-dependent weakening mechanisms, fragmentation can account for the observed variability in runout. We use laboratory-scale experimental avalanches to simulate and analyse the role of fragmentation. We find that fragmentation consumes energy but also increases avalanche mobility. It does so systematically and predictably.
David Jon Furbish, Joshua J. Roering, Tyler H. Doane, Danica L. Roth, Sarah G. W. Williams, and Angel M. Abbott
Earth Surf. Dynam., 9, 539–576,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.
David Jon Furbish, Sarah G. W. Williams, Danica L. Roth, Tyler H. Doane, and Joshua J. Roering
Earth Surf. Dynam., 9, 577–613,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,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,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.
Saptarshi Dey, Rasmus C. Thiede, Arindam Biswas, Naveen Chauhan, Pritha Chakravarti, and Vikrant Jain
Earth Surf. Dynam., 9, 463–485,Short summary
Ongoing deformation of the Himalaya is not constrained to its southern extremity. With morphometric analysis using a high-resolution digital elevation model, satellite image analysis, luminescence chronology of fluvial terraces and field observations, we identify a zone of rapid rock uplift in the interior of the Kashmir Himalaya. Our results suggest active tectonic and structural control on the growth of topography in the Himalayan interiors over multi-millennial timescales.
Arthur Depicker, Gerard Govers, Liesbet Jacobs, Benjamin Campforts, Judith Uwihirwe, and Olivier Dewitte
Earth Surf. Dynam., 9, 445–462,Short summary
We investigated how shallow landslide occurrence is impacted by deforestation and rifting in the North Tanganyika–Kivu rift region (Africa). We developed a new approach to calculate landslide erosion rates based on an inventory compiled in biased © Google Earth imagery. We find that deforestation increases landslide erosion by a factor of 2–8 and for a period of roughly 15 years. However, the exact impact of deforestation depends on the geomorphic context of the landscape (rejuvenated/relict).
Jules Le Guern, Stéphane Rodrigues, Thomas Geay, Sébastien Zanker, Alexandre Hauet, Pablo Tassi, Nicolas Claude, Philippe Jugé, Antoine Duperray, and Louis Vervynck
Earth Surf. Dynam., 9, 423–444,Short summary
Despite the inherent difficulties in quantifying its value, sediment transport is essential to understanding fluvial systems. This study tries to improve the measurement by comparing several methods. Acoustic methods are compared to direct measurements with samplers. The hydrophone is well adapted to quantify sediment transport in mountain streams, but this study shows the potential and the efficiency of this device in large lowland rivers.
Velio Coviello, Lucia Capra, Gianluca Norini, Norma Dávila, Dolors Ferrés, Víctor Hugo Márquez-Ramírez, and Eduard Pico
Earth Surf. Dynam., 9, 393–412,Short summary
The Puebla–Morelos earthquake (19 September 2017) was the most damaging event in central Mexico since 1985. The seismic shaking produced hundreds of shallow landslides on the slopes of Popocatépetl Volcano. The larger landslides transformed into large debris flows that travelled for kilometers. We describe this exceptional mass wasting cascade and its predisposing factors, which have important implications for both the evolution of the volcanic edifice and hazard assessment.
Jon D. Pelletier
Earth Surf. Dynam., 9, 379–391,Short summary
The sizes and shapes of alluvial channels vary in a systematic way with the water flow they convey during large floods. It is demonstrated that the depth of alluvial channels is controlled by the resistance of channel bank material to slumping, which in turn is controlled by clay content. Deeper channels have faster water flow in a manner controlled by the critical hydraulic state to which channels tend to evolve. Channel width and slope can be further quantified using conservation principles.
Chenge An, Marwan A. Hassan, Carles Ferrer-Boix, and Xudong Fu
Earth Surf. Dynam., 9, 333–350,Short summary
Mountain rivers are characterized by fluctuations of water flow, including both flood and inter-flood low flow. Recently, increasing attention has been paid to how inter-flood low flow affects the sediment transport in subsequent floods. Here we present a series of flume experiments. Results show that the existence of inter-flood low flow can reduce the sediment transport at the beginning of the subsequent flood. However, such an effect is gradually erased with the increase of flow intensity.
Tyler H. Doane, Jon D. Pelletier, and Mary H. Nichols
Earth Surf. Dynam., 9, 317–331,Short summary
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.
Benedetta Dini, Georgina L. Bennett, Aldina M. A. Franco, Michael R. Z. Whitworth, Kristen L. Cook, Andreas Senn, and John M. Reynolds
Earth Surf. Dynam., 9, 295–315,Short summary
We use long-range smart sensors connected to a network based on the Internet of Things to explore the possibility of detecting hazardous boulder movements in real time. Prior to the 2019 monsoon season we inserted the devices in 23 boulders spread over debris flow channels and a landslide in northeastern Nepal. The data obtained in this pilot study show the potential of this technology to be used in remote hazard-prone areas in future early warning systems.
Roberto Fernández and Gary Parker
Earth Surf. Dynam., 9, 253–269,Short summary
We present a set of observations from laboratory experiments on meltwater meandering rivulets on ice and compare them (qualitatively and quantitatively) to patterns commonly found in meandering channels flowing over different materials. Our channels display great similarities with real rivers in spite of being much smaller. Higher temperature differences between water and ice create deeper and less sinuous channels with bends that preferentially point downstream and are not as rounded.
Daniel J. Ciarletta, Jennifer L. Miselis, Justin L. Shawler, and Christopher J. Hein
Earth Surf. Dynam., 9, 183–203,Short summary
The world's sandy coastlines are increasingly altered by humans and sea-level rise, yet quantitative relationships between coastal landscapes and sediment availability remain poorly described. Using a novel modeling framework, we explore the evolution of coastal barrier islands under varying rates of sea-level rise and sediment availability. Our model results suggest that as sea levels increase, minor changes in sediment availability could result in rapid changes to barrier coasts.
Alexander R. Groos, Janik Niederhauser, Luise Wraase, Falk Hänsel, Thomas Nauss, Naki Akçar, and Heinz Veit
Earth Surf. Dynam., 9, 145–166,Short summary
Large sorted stone stripes have been discovered on the 4000 m high central Sanetti Plateau of the tropical Bale Mountains in Ethiopia. The stripes are a mystery as similar landforms have so far only been reported in the temperate zone and polar regions. Our investigations suggest that the stripes formed in the vicinity of a former ice cap on the plateau during a much colder climatic period. The distinct pattern is the result of a process related to cyclic freezing and thawing of the ground.
Daniel Peifer, Cristina Persano, Martin D. Hurst, Paul Bishop, and Derek Fabel
Earth Surf. Dynam., 9, 167–181,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.
Sophie Bodek and Douglas J. Jerolmack
Earth Surf. Dynam. Discuss.,
Revised manuscript accepted for ESurfShort summary
As rocks are transported, they undergo two attrition mechanisms: chipping, shallow cracking at low collision energies, and fragmentation, significant fracture growth from high-energy impacts. We examine the mass and shape evolution of concrete particles in a rotating drum to experimentally delineate the boundary between chipping and fragmentation. By connecting the mechanics of these attrition processes to resulting shape evolution, we can use particle shape to infer past transport conditions.
Magdalena Uber, Guillaume Nord, Cédric Legout, and Luis Cea
Earth Surf. Dynam., 9, 123–144,Short summary
Understanding soil erosion and suspended sediment transport is an important issue in terms of soil and water resources management. This study analyzes the impact of choices made during numerical model setup on the modeled suspended sediment dynamics at the outlet of two mesoscale watersheds. While the modeled liquid and solid discharges were found to be sensitive to these choices, the actual location of sediment sources in each catchment was the most important feature.
Chen Wang, Lennert Schepers, Matthew L. Kirwan, Enrica Belluco, Andrea D'Alpaos, Qiao Wang, Shoujing Yin, and Stijn Temmerman
Earth Surf. Dynam., 9, 71–88,Short summary
Coastal marshes are valuable natural habitats with normally dense vegetation. The presence of bare patches is a symptom of habitat degradation. We found that the occurrence of bare patches and regrowth of vegetation is related to spatial variations in soil surface elevation and to the distance and connectivity to tidal creeks. These relations are similar in three marshes at very different geographical locations. Our results may help nature managers to conserve and restore coastal marshes.
Kumar Gaurav, François Métivier, A V Sreejith, Rajiv Sinha, Amit Kumar, and Sampat Kumar Tandon
Earth Surf. Dynam., 9, 47–70,Short summary
This study demonstrates an innovative methodology to estimate the formative discharge of alluvial rivers from remote sensing images. We have developed an automated algorithm in Python 3 to extract the width of a river channel from satellite images. Finally, this channel width is translated into discharge using a semi-empirical regime equation developed from field measurements and threshold channel theory that explains the first-order geometry of alluvial channels.
Georgios Maniatis, Trevor Hoey, Rebecca Hodge, Dieter Rickenmann, and Alexandre Badoux
Earth Surf. Dynam., 8, 1067–1099,Short summary
One of the most interesting problems in geomorphology concerns the conditions that mobilise sediments grains in rivers. Newly developed
smartpebbles allow for the measurement of those conditions directly if a suitable framework for analysis is followed. This paper connects such a framework with the physics used to described sediment motion and presents a series of laboratory and field smart-pebble deployments. Those quantify how grain shape affects the motion of coarse sediments in rivers.
William D. Smith, Stuart A. Dunning, Stephen Brough, Neil Ross, and Jon Telling
Earth Surf. Dynam., 8, 1053–1065,Short summary
Glacial landslides are difficult to detect and likely underestimated due to rapid covering or dispersal. Without improved detection rates we cannot constrain their impact on glacial dynamics or their potential climatically driven increases in occurrence. Here we present a new open-access tool (GERALDINE) that helps a user detect 92 % of these events over the past 38 years on a global scale. We demonstrate its ability by identifying two new, large glacial landslides in the Hayes Range, Alaska.
David L. Adams and Andrea Zampiron
Earth Surf. Dynam., 8, 1039–1051,Short summary
This paper presents a novel method of estimating the relative contribution of different physical scales of river bed topography to the total roughness length, based on thalweg elevation profiles. By providing more detailed information regarding the interaction between surface topography and fluid dynamics, the proposed technique may contribute to advances in hydraulics, channel morphodynamics, and bedload transport. Also, it may provide alternatives to existing representative roughness metrics.
Kristian Svennevig, Trine Dahl-Jensen, Marie Keiding, John Peter Merryman Boncori, Tine B. Larsen, Sara Salehi, Anne Munck Solgaard, and Peter H. Voss
Earth Surf. Dynam., 8, 1021–1038,Short summary
The 17 June 2017 Karrat landslide in Greenland caused a tsunami that killed four people. We apply a multidisciplinary workflow to reconstruct a timeline of events and find that three historic landslides occurred in 2009, 2016, and 2017. We also find evidence of much older periods of landslide activity. Three newly discovered active slopes might pose a future hazard. We speculate that the trigger for the recent events is melting permafrost due to a warming climate.
Steven A. H. Weisscher, Marcio Boechat-Albernaz, Jasper R. F. W. Leuven, Wout M. Van Dijk, Yasuyuki Shimizu, and Maarten G. Kleinhans
Earth Surf. Dynam., 8, 955–972,Short summary
Accurate and continuous data collection is challenging in physical scale experiments. A novel means to augment measurements is to numerically model flow over the experimental digital elevation maps. We tested this modelling approach for one tidal and two river scale experiments and showed that modelled water depth and flow velocity closely resemble the measurements. The implication is that conducting experiments requires fewer measurements and results in flow data of better overall quality.
Carina Helm, Marwan A. Hassan, and David Reid
Earth Surf. Dynam., 8, 913–929,Short summary
Forested, gravel-bed streams possess complex channel morphologies which are difficult to objectively characterize. This paper describes a novel technique using a remotely piloted aircraft (RPA) to characterize these systems below the forest canopy. The results demonstrate the accuracy and coverage of RPAs for objectively characterizing and classifying these systems relative to more traditional, time-consuming techniques that are generally used in these environments.
Nathan J. Lyons, Pedro Val, James S. Albert, Jane K. Willenbring, and Nicole M. Gasparini
Earth Surf. Dynam., 8, 893–912,Short summary
Organisms evolve in ever-changing environments under complex process interactions. We applied a new software modelling tool to assess how changes in river course impact the evolution of riverine species. Models illustrate the climatically and tectonically forced landscape changes that can drive riverine biodiversity, especially where topographic relief is low. This research demonstrates that river course changes can contribute to the high riverine biodiversity found in real-world lowland basins.
Andy R. Emery, David M. Hodgson, Natasha L. M. Barlow, Jonathan L. Carrivick, Carol J. Cotterill, Janet C. Richardson, Ruza F. Ivanovic, and Claire L. Mellett
Earth Surf. Dynam., 8, 869–891,Short summary
During the last ice age, sea level was lower, and the North Sea was land. The margin of a large ice sheet was at Dogger Bank in the North Sea. This ice sheet formed large rivers. After the ice sheet retreated down from the high point of Dogger Bank, the rivers had no water supply and dried out. Increased precipitation during the 15 000 years of land exposure at Dogger Bank formed a new drainage network. This study shows how glaciation and climate changes can control how drainage networks evolve.
Matteo Saletti and Marwan A. Hassan
Earth Surf. Dynam., 8, 855–868,Short summary
Mountain streams often display a stepped morphology but the conditions under which these steps form, remain stable, and eventually collapse are still not entirely clear. We run flume experiments to study how (a) the amount of sediment input and (b) channel width variations affect step dynamics in steep channels. Steps form preferentially in areas of flow convergence (channel narrowing) and their frequency is higher when sediment supply is larger than zero but smaller than the transport capacity.
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Shells are biogenic particles that are widespread throughout natural sandy environments and can affect the bed roughness and seabed erodibility. As studies are presently lacking, we experimentally measured ripple formation and migration using natural sand with increasing volumes of shell material under unidirectional flow in a racetrack flume. We show that shells expedite the onset of sediment transport, reduce ripple dimensions and slow their migration rate.
Shells are biogenic particles that are widespread throughout natural sandy environments and can...