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This article examines the epistemic practices of interpretive field geomorphology—that is, the in‐the‐moment act of "seeing the landscape" geomorphologically. Drawing on the philosophical works of Wittgenstein and Merleau‐Ponty, it aims to bring to light the complex, multi‐dimensional, knowledge‐producing process of field observation and interpretation. Methodologically the study is based on geomorphologists' accounts of their fieldwork, gathered through questionnaire and interviews. By paying attention to what geomorphologists say they are doing in the field, interpretive field geomorphology is articulated as a combined cognitive, social, embodied, and affective experience through which understanding is arrived at. The paper thus sheds light on one part of what Brierley et al. call "the dark art" of geomorphological interpretation, and draws out implications in terms of researcher positionality, researcher training, and offering an epistemic justification for field‐based pedagogies. Key messages: Interpretive field geomorphology is an epistemic practice entailing social, bodily, and affective dimensions.Researcher positionality includes prior experience of interpreting landscapes and doing so with others.Field experience contributes to both development of skill in geomorphological interpretation and development of understanding, which is more than just cognitive. [ABSTRACT FROM AUTHOR]

Geomorphologists have long debated the relative importance of disturbance magnitude, duration, and frequency in shaping landscapes. For river‐channel adjustment by floods, some argue that the cumulative hydrograph, rather than magnitude or duration, matters most. However, studies of flood‐induced river‐channel change often draw upon small data sets. Here, we combine Sentinel‐2 imagery with flow data from laterally active rivers to address this question using a larger data set. We apply automated algorithms in Google Earth Engine to map rivers and detect their lateral shifting; we generate a large data set to quantify planform erosion during 175 floods at 34 selected sites. Erosion during these floods is best explained by their duration and then their cumulative hydrograph. We use a random forest regression model to predict flood‐induced erosion, with potential applications for hazard management. Ultimately, better global data on sediment supply and caliber would help us to understand flood‐driven change to river planforms. Plain Language Summary: Some rivers change their shape over time. In this paper, we explore how high‐flow events drive these river channels to reshape themselves. We use Google Earth Engine to automatically map the shapes of rivers in satellite images. We apply this method to pairs of satellite images before and after high‐flow events, to understand how the river shape is changed by the event. We compare the amount of channel widening measured to aspects of the high‐flow event, including its peak, duration, and total flow. We do so for 175 events, and find that the duration and total flow are most important for explaining how much a channel widens during the event. Finally, we build a statistical model to predict the average amount of channel widening for a given high‐flow event. This method has potential applications for hazard management in rivers that are known to change their shape. Key Points: We develop a method to quantify river planform change after flood events, using Google Earth EngineWe do so for a data set of 175 floods that exceeded the 80th percentile stage, at 34 flow gauging sites on laterally active riversPlanform erosion during these high‐flow events was most correlated with the event duration, and then the summed hydrograph [ABSTRACT FROM AUTHOR]

Data analysis methods have scarcely kept pace with the rapid increase in Earth observations, spurring the development of novel algorithms, storage methods, and computational techniques. For scientists interested in Mars, the problem is always the same: there is simultaneously never enough of the right data and an overwhelming amount of data in total. Finding sufficient data needles in a haystack to test a hypothesis requires hours of manual data screening, and more needles and hay are added constantly. To date, the vast majority of Martian research has been focused on either one-off local/regional studies or on hugely time-consuming manual global studies. Machine learning in its numerous forms can be helpful for future such work. Machine learning has the potential to help map and classify a large variety of both features and properties on the surface of Mars and to aid in the planning and execution of future missions. Here, we outline the current extent of machine learning as applied to Mars, summarize why machine learning should be an important tool for planetary geomorphology in particular, and suggest numerous research avenues and funding priorities for future efforts. We conclude that: (1) moving toward methods that require less human input (i.e., self- or semi-supervised) is an important paradigm shift for Martian applications, (2) new robust methods using generative adversarial networks to generate synthetic high-resolution digital terrain models represent an exciting new avenue for Martian geomorphologists, (3) more effort and money must be directed toward developing standardized datasets and benchmark tests, and (4) the community needs a large-scale, generalized, and programmatically accessible geographic information system (GIS). [ABSTRACT FROM AUTHOR]

One of the pillars of geomorphology is the study of geomorphic processes and their drivers, dynamics, and impacts. Like all activity that transfers energy to Earth's surface, a wide range of geomorphic process types create seismic waves that can be measured with standard seismic instruments. Seismic signals provide continuous high-resolution coverage with a spatial footprint that can vary from local to global, and in recent years, efforts to exploit these signals for information about surface processes have increased dramatically, coalescing into the emerging field of environmental seismology. The application of seismic methods has the potential to drive advances in our understanding of the occurrence, timing, and triggering of geomorphic events, the dynamics of geomorphic processes, fluvial bedload transport, and integrative geomorphic system monitoring. As new seismic applications move from development to proof of concept to routine application, integration between geomorphologists and seismologists is key for continued progress. Geomorphic activity on Earth's surface produces seismic signals that can be measured with standard seismic instruments. Seismic methods are driving advances in our understanding of the occurrence, triggering, and internal dynamics of a range of geomorphic processes. Dedicated seismic-based observatories offer the potential to comprehensively characterize geomorphic activity and its impacts across a landscape. Collaboration between seismologists and geomorphologists is fostering the development of new applications, models, and analysis techniques for geomorphic seismology. [ABSTRACT FROM AUTHOR]

This essay argues for taking fieldwork seriously, but not too seriously. It focuses on geologists and geomorphologists in the United States in the post–World War II decades who used irony, satire, and self-conscious staging to negotiate the contradictions between the tradition of frontier fieldwork that they had inherited from the late nineteenth century and the realities of mid-twentieth-century fieldwork, which they often found hard to fit into the heroic mold. Poking fun at the fieldwork tradition, the essay argues, helped them claim that tradition as their own even while constructing new scientific personas and practices that diverged from it in a number of ways. [ABSTRACT FROM AUTHOR]

The Co nfined M orphologies Ma pping (CoMMa) Toolbox, a novel ArcGIS Pro python toolbox expressly created for semi-automated seabed morphological mapping, is presented here. The toolbox includes a selection of tools for the pre-processing, delineation and description of confined features on a digital elevation model (DEM) that are either negative or positive. The CoMMa Toolbox addresses the need for a flexible and multi-faceted solution applicable to different mapping problems, also encapsulating and re-interpreting existing methodologies. This study also evaluates, qualitatively and quantitatively, the performance of CoMMa delineations performed on a synthetic bathymetry DEM with 150 coral mounds of known characteristics against manual digitisations completed by five expert geomorphologists. The results show that the best CoMMa delineation falls within the range of competence demonstrated by the expert manual mappers. Edge evaluation metrics and attribute error scores are comparable or often superior to four of the five human delineations, although the Toolbox never reaches the performance of the best expert. Nevertheless, the semi-automated techniques can be of assistance to any user, providing rapid, visually unbiased and consistent delineations, thus saving time: they can then be optimised manually where desirable. Moreover, while the toolbox was created for marine geomorphometry, it can be applied to any DEM, either marine, terrestrial or extra-terrestrial. The CoMMa Toolbox is available in a public GitHub repository with a thorough user guide. • We present CoMMa, a toolbox that allows users to characterise confined morphologies. • A synthetic seabed DEM was used to gain statistical control on the accuracy of the toolbox. • CoMMa delineations are compared to those done manually by five expert mappers. • The results by CoMMa are as precise or better than those of the manual mappers. • CoMMa is freely available on GitHub with a complete User Guide. [ABSTRACT FROM AUTHOR]

Pottery from the collection of Grgur Bučić, a prolific researcher on the island of Hvar, is analyzed in this paper. This pottery originated in Markova Cave (on the island of Hvar), and a variety of ceramic forms (bowls, pots, cups, beakers) are present that may be dated from the Neolithic to the Middle Ages based on their decorations, handles and shapes. [ABSTRACT FROM AUTHOR]

Landscape morphology reflects drivers such as tectonics and climate but is also modulated by underlying rock properties. While geomorphologists may attempt to quantify the influence of rock strength through direct comparisons of landscape morphology and rock strength metrics, recent work has shown that the contact migration resulting from the presence of mixed lithologies may hinder such an approach. Indeed, this work counterintuitively suggests that channel slopes within weaker units can sometimes be higher than channel slopes within stronger units. Here, we expand upon previous work with 1-D stream power numerical models in which we have created a system for quantifying contact migration over time. Although previous studies have developed theories for bedrock rivers incising through layered stratigraphy, we can now scrutinize these theories with contact migration rates measured in our models. Our results show that previously developed theory is generally robust and that contact migration rates reflect the pattern of kinematic wave speed across the profile. Furthermore, we have developed and tested a new approach for estimating kinematic wave speeds. This approach utilizes channel steepness, a known base-level fall rate, and contact dips. Importantly, we demonstrate how this new approach can be combined with previous work to estimate erodibility values. We demonstrate this approach by accurately estimating the erodibility values used in our numerical models. After this demonstration, we use our approach to estimate erodibility values for a stream near Hanksville, UT. Because we show in our numerical models that one can estimate the erodibility of the unit with lower steepness, the erodibilities we estimate for this stream in Utah are likely representative of mudstone and/or siltstone. The methods we have developed can be applied to streams with temporally constant base-level fall, opening new avenues of research within the field of geomorphology. [ABSTRACT FROM AUTHOR]

This paper illustrates the scope and contribution that the discipline of geomorphology can offer in environmental litigation. The case in question was filed by two plaintiffs who contended that the construction of a storage facility on an adjacent property had caused significant disturbance of the topsoil, and that runoff from the impermeable surfaces (e.g., roofs, driveways) had exacerbated the problem by eroding and transporting soil and fill material from the facility directly into three ponds owned by them. They sued for $1.6 million to cover dredging, restoration of the ponds, and disposal of the sediment. Utilizing a range of geomorphological techniques, I was able to determine the most likely source area(s) of eroded sediment within the basin and quantify the extent to which the defendant's property contributed runoff and sediment to the ponds. The lawsuit was dismissed before ever going to trial. In the paper, I discuss the steps involved in the process of being an expert witness and also share some of the advice I have received from attorneys with whom I have worked. I emphasize the importance of setting any case study within a larger spatial context and encourage my fellow geomorphologists to become involved as experts in litigation because, in most instances, we can contribute to an appropriate outcome. [ABSTRACT FROM AUTHOR]

From the earlier reviews it is clear that a strong tectonic and macro-geomorphology theme dominated research in the first half of the last century with erosion, land degradation and applied research gaining prominence in the latter half (Beckedahl et al., [1]). Targeting the imminent inauguration of the International Association of Geomorphology (IAG) planned for I The Second International Geomorphology Conference i in 1992 in Canada, the 1988 local geomorphology symposium in Mthata provided the platform to launch the Southern African Association of Geomorphologists (SAAG). Holmes et al. ([9]) summarize the more recent research into six dominant sub-themes, namely fluvial geomorphology, glacial and periglacial geomorphology, rock weathering, arid and semi-arid geomorphology, coastal and estuarine geomorphology and applied geomorphology. Studies on the geomorphology of southern African have a long history extending back to the pioneering work in the early parts of the 20 SP th sp Century by Dixey, Wellington and King, amongst others (see Beckedahl et al., [1]). [Extracted from the article]

Antony R. "Tony" Orme passed away on 30 May 2020. Professor Orme was one of the US' most distinguished geomorphologists and physical geographers. This Classics Revisited piece honors the memory of Professor Tony Orme and examines his classic book Ireland, an outstanding example of a regional geography book with a strong foundation in physical geography. [ABSTRACT FROM AUTHOR]

Cryoplanation terraces are prominent but enigmatic landforms found in present and past periglacial environments. Geomorphologists have debated for more than a century over processes involved in the formation of these elevated, step-like, bedrock features. Presented here are the first numerical surface exposure ages and scarp retreat rates from cryoplanation terraces in the Yukon-Tanana Upland (YTU) in Alaska, part of unglaciated eastern Beringia, obtained from terrestrial cosmogenic nuclides (TCN) in surface boulders. Ages comprise six 10Be TCN ages from two terrace treads near Eagle Summit and six 36 Cl ages from two treads on Mt. Fairplay. Based on these exposure ages, scarps at both locations were last actively eroding from 49 to 22.4 ka. Both locations exhibit time-transgressive development, particularly near scarp-tread junctions. Boulder exposure ages and distances between sampled boulder locations were used to estimate scarp retreat rates of 0.11 to 0.56 cm/yr. These numerical exposure ages presented here demonstrate that the cryoplanation terraces in the YTU are diachronous surfaces actively eroding during multiple cold intervals. With these results, hypotheses for cryoplanation terrace formation are discussed and evaluated for the YTU, including those based on geologic structure, nivation, and the influence of permafrost. [ABSTRACT FROM AUTHOR]

Climatic geomorphologists, and eolian geomorphologists in particular, have always been interested in studying dunes to understand and construct past climatic conditions. Smith's 1965 paper presents an excellent example of a reconnaissance piece of scientific work that set the foundation for (1) using aerial photo-interpretation to provide chronological information about dune fields; (2) the use of eolian processes and landforms as climate change indicators; and (3) extraterrestrial or planetary geomorphology. This article briefly describes Smith's background, background on Nebraska Sand Hills, and the impact and legacy of Smith's classic paper. [ABSTRACT FROM AUTHOR]

The 51st Binghamton Geomorphology Symposium was held on October 15–17, 2021, at Middle Tennessee State University in Murfreesboro, Tennessee. Postponed from 2020 because of the COVID-19 pandemic, this symposium focused on the theme of Geomorphology in the Anthropocene while navigating the unique challenges presented by the waning pandemic. Despite these challenges, twelve live oral presentations were delivered either virtually or in-person and poster presentations were presented under the themes of Biogeomorphology, Climate Change, Land degradation and Erosion, Sedimentological Processes, The Critical Zone, and Natural Hazards. Through continued symposia and special issues such as this one, the Binghamton Geomorphology Symposium seeks to assess the rate of change of geomorphic processes, promote advancement through technological and scientific methodologies, and understand the new paradigms presented by the rapidly changing Earth surface. The authors of this introduction emphasize that, in light of the rapidly-changing geomorphic processes and feedbacks with the climate and biotic systems they affect, practicing geomorphologists and researchers must prioritize sharing our understanding of the natural world and the extent of humans' modifications of all its cycles with the general public and policy-makers: those with little or no formal training in geomorphology, yet who wield considerable power to alter geomorphic processes. [ABSTRACT FROM AUTHOR]

Abstract Sinkholes are the most typical surface feature of karst landscapes. Their correct mapping is of great importance for a proper assessment of the possible occurrence of new events, and the likely effects they could have on the anthropogenic environment. In this work we compare and discuss different ways to map sinkholes, including heuristic approach, automatic mapping through different resolution DTMs, and digital aerial photo interpretation, aimed at highlighting advantages and drawbacks of the multiple approaches. For our purpose we use a study area in the Murge of Apulia, SE Italy, where many sinkholes of several typologies are present to characterize the landscape. To evaluate the reliability of the sinkhole mapping, we set up a conceptual methodology that integrates a semi-automatic method with the heuristic approach, with a special focus on the importance of incorporating digital stereoscopic interpretation. In detail, we used as input two DTMs at different resolution, aimed to test the robustness of the automatic method in different circumstances. Comparison of the data produced by the different approaches illustrated how the number, density and boundaries of the sinkholes may vary as a function of the input data. The automated mapping provides reliable results in terms of number, dimensions, and morphometric attributes of sinkholes, and appears to be particularly useful when large areas must be analyzed. Within the whole process, we stress the role of the expert geomorphologist who must determine the accuracy of the product obtained with the automated mapping by correcting/eliminating features not attributable to karst processes. The presented approach highlights the potential of digital stereoscopy in substantially decreasing the errors encountered with traditional analog mapping, simultaneously reducing the working time significantly. Highlights • Automated mapping sinkholes using different resolution DTMs gives different results. • The quality of the inventory can be biased by uncertainties linked to multiple factors. • Combining multiple mapping techniques reduce bias obtaining more reliable maps. [ABSTRACT FROM AUTHOR]

The term 'concept' as normally used by geomorphologists refers to defined ideas in the corpus of knowledge, World 3 of Popper. However, psychologists and philosophers regard them as parts of mental processes that take place in memory, World 2. A World 3 perspective demands clarity and definition of ideas, whereas a World 2 perspective is about fluidity and power of association with other ideas. In memory, concepts act as mnemonics. Taking a World 2 perspective has implications for research and teaching. It helps us to understand the use of concepts in the development of ideas, through imagination and conjecture, as well as matters of problem selection and mode of argument. Testability, though not an intrinsic aspect of concepts, is also intimately bound up with conceptualisation of problems and method. These notions of concepts have implications for research and teaching since they affect how we understand and practice geomorphology as a knowledge domain and how we address the mental skills of memory, imagination and creativity. [ABSTRACT FROM AUTHOR]

Abstract This paper identifies a terrestrial analog for linear dune fields in the Chasma Boreale, located in the north polar region of Mars, and analyzes it to explain linear dune formation. The straight indurated linear dunes are elongated downwind of dome dunes and barchans under a unimodal wind regime, providing a novel research opportunity for geomorphologists to investigate the coexistence of transverse and longitudinal dunes and the effect of sediment induration on dune morphology. The linear dunes around the Chaerhan salt lake in the Qaidam Basin are good analogs for the Chasma Boreale linear dunes because of the similarities in dune morphology and evolution process. Further, the effects of the indurating agents (salt and ice) on the formation of the linear dunes are similar in both locations. In this paper, we have contrasted and analyzed their dune patterns, the influence of cohesive sediment, and wind regimes in the two areas. The formation process and underlying mechanisms that create the linear dunes are analyzed through geomorphological evidence and dune flow simulation experiments. The results show that there is a remarkable morphological resemblance between the two areas. Cohesive sediments, especially the interbedded frozen laminae on Mars, increase dune stability, and thus allow the formation of linear dunes under a small divergence-angle in a bidirectional wind regime. The proto-linear dune facilitates the deposition of sediment along the major axis of the dune, and the lateral wind maintains and promotes the development of linear dunes. We also discuss how cohesive sediment influences dune morphology and leads to a transition from barchans to linear dunes, and we examine the feedback between dune form and airflow. The different effects of sediment induration on dune morphology make the determination of aeolian patterns less certain, which has implications for the development of climate models of Mars and Titan. Highlights • Qaidam Basin linear dunes are viable analogs for the Chasma Boreale linear dunes. • Dune flow simulation experiments show the feedback between dune form and airflow. • The effects of the indurating agents (salt and ice) on the formation of linear dunes are similar. • Direct geomorphological evidence for the transition in dune morphology is offered. • The coexistence of transverse and longitudinal dunes reflects complex external environment. [ABSTRACT FROM AUTHOR]

In 1985, more than thirty geomorphologists, planetary scientists, and remote sensing specialists gathered at a conference center in Oracle, Arizona, to discuss an emerging area of research that they called “mega-geomorphology.” Building on a conference of the same name held in London in 1981, they argued that new techniques of remote sensing and insights emerging from the study of extraterrestrial planets had created opportunities for geomorphology to broaden its spatial and temporal scope. This new approach was, however, neither unproblematic nor uncontested. In the discussions around mega-geomorphology that took place in the mid-1980s, the perceived conflict between the use of remote-sensing techniques to observe phenomena on vast spatial scales, on one hand, and the disciplinary centrality of fieldwork and field experience to geomorphology, on the other, was a recurrent theme. In response, mega-geomorphologists attempted to re-situate fieldwork and re-narrate disciplinary histories in such a way as to make remote sensing and planetary science not only compatible with geomorphological traditions but also means of revitalizing them. Only partially successful, these attempts reveal that the process of adopting a planetary perspective in geomorphology, as in other earth sciences, was neither straightforward nor inevitable. They also show how the field and fieldwork could remain central to geomorphology while also being extensively revised in light of new technical possibilities and theoretical frameworks. [ABSTRACT FROM AUTHOR]

Regional studies of fluvial landforms and long-term (Quaternary) landscape development in remote mountain landscapes routinely use satellite-derived DEM data sets. The SRTM and ASTER DEMs are the most commonly utilised because of their longer availability, free cost, and ease of access. However, rapid technological developments mean that newer and higher resolution DEM data sets such as ALOS World 3D (AW3D) and TanDEM-X are being released to the scientific community. Geomorphologists are thus faced with an increasingly problematic challenge of selecting an appropriate DEM for their landscape analyses. Here, we test the application of four medium resolution DEM products (30 m = SRTM, ASTER, AW3D; 12 m = TanDEM-X) for qualitative and quantitative analysis of a fluvial mountain landscape using the Dades River catchment (High Atlas Mountains, Morocco). This landscape comprises significant DEM remote sensing challenges, notably a high mountain relief, steep slopes, and a deeply incised high sinuosity drainage network with narrow canyon/gorge reaches. Our goal was to see which DEM produced the most representative best fit drainage network and meaningful quantification. To achieve this, we used ArcGIS and Stream Profiler platforms to generate catchment hillshade and slope rasters and to extract drainage network, channel long profile and channel slope, and area data. TanDEM-X produces the clearest landscape representation but with channel routing errors in localised high relief areas. Thirty-metre DEMs are smoother and less detailed, but the AW3D shows the closest fit to the real drainage network configuration. The TanDEM-X elevation values are the closest to field-derived GPS measurements. Long profiles exhibit similar shapes but with minor differences in length, elevation, and the degree of noise/smoothing, with AW3D producing the best representation. Slope-area plots display similarly positioned slope-break knickpoints with modest differences in steepness and concavity indices, but again best represented by AW3D. Collectively, our study shows that despite the higher effective resolution of TanDEM-X (12 m), the AW3D (30 m) data performs strongly across all analyses suggesting that it currently offers the greatest potential for regional mountain geomorphological analyses. [ABSTRACT FROM AUTHOR]

A key skill that geomorphologists possess is the ability to use multi‐scale perspectives in their interpretations of landscapes. One way to gain these perspectives is with the use of nested hierarchical frameworks. In fluvial geomorphology, such frameworks help with assessment of large‐scale controls (e.g., tectonic activity, climate change) on the pattern and dynamics of smaller‐scale physical features (e.g., channels, floodplains, bars), and conversely illustrate how these smaller‐scale features provide the building blocks from which to make interpretations of fluvial processes and dynamics over larger spatial and temporal scales. Given the rapid pace of technological developments, the range of relatively inexpensive tools available for visualising and mapping landscapes at different spatial scales is expanding exponentially. In this paper, which focuses on the World Heritage‐listed Okavango Delta in Botswana, we demonstrate how various visualisations generated by different technologies at different spatial scales (catchment, landscape unit, reach, site and geomorphic unit) are providing critical baseline information to enhance interpretation and communication of fluvial geomorphology, with potential application in water resources management. In particular, our nested hierarchical approach could be used as an interactive communication tool for non‐specialists and embedded within existing and future management plans for the Delta. The construction of nested hierarchies that synthesise information and analyses can be a valuable addition to the environmental manager's toolkit. [ABSTRACT FROM AUTHOR]

For several decades, geomorphologists have focused on the functioning of geomorphic systems after deglaciation. The relative importance of paraglacial vs. periglacial processes has been highly debated. At present, the development of dating techniques allows to contribute to this debate. We reconstruct in this paper the geomorphic evolution of Tindastóll mountain slopes in Laxárdalur valley (Skagafjörður area, central northern Iceland), where a chronological framework can be established through tephrochronology and an assemblage of dated raised beaches. Volumetric calculations of constructed and excavated landforms were created from field data and from DEM and geographical information system techniques. Collectively, our data exhibit a first stage of paraglacial landsliding during the first half of the Holocene, followed by a stage of scree and rockglacier development (during the second half of the Holocene, but before 1100 AD). Our estimations indicate that more than 85% of the total sediment production were due to rock slope failure, and the rate of bedrock denudation due to periglacial processes was about one half of the rate of paraglacial processes. Nevertheless, paraglacial and periglacial processes cannot be seen here as antagonistic processes: they are organized in a sequence during which periglacial processes are conditioned (enhancement of bedrock denudation rates) by fracturing and consequent mass wasting. Screes and concomitant rockglaciers were indeed preconditioned by the landslide, while areas non-affected by landslides have remained mostly intact, characterized by a very low rate of accumulation due to geomorphic (periglacial) activity. [ABSTRACT FROM AUTHOR]

River capture is a surficial process that can lead to drainage reorganization and have significant impacts on sediment dispersal and biotic evolution. Discovery and study of river capture events are helpful in revealing the history of drainage basins, however, the present-day identification of river capture mainly depends on field and map observations by geomorphologists, who lack an automatic method. In the case of a large-scale drainage system with a complicated stream network, a field investigation is too time-consuming and costly. This study aims to develop a novel method for automatic river capture detection based on planform morphology and χ-plots of the stream network. The whole method can be described as a workflow including three steps: (1) searching candidate regions where river capture may have occurred; (2) iterating over each candidate region and roughly detecting the captor, captured, reversal, and beheaded rivers using the planform pattern of the stream network; (3) verifying the river capture with a χ-elevation plot in the candidate region found by rough detection. The description of the method is followed by two case studies from China and Spain, demonstrating the ability of the method to identify the location where the river capture might occur. We also discuss the parameters that must be optimized before extracting the river capture efficiently from the stream network. • A novel method is developed to automatically detect river capture events based on morphological features. • The workflow includes searching candidate regions, detecting river capture, and identifying river capture with a χ-plot. • Two case studies demonstrate the ability of the method to identify the location where the river capture might occur. [ABSTRACT FROM AUTHOR]

Landforms resulting from the interaction between paleo-glaciers and karst are studied by using the Sierra de los Grajos (Cantabrian Mountains) as a model. This area contains glacial landforms that have not interested geomorphologists due to their low altitude (Peña Castillo is about 1857 m a.s.l.), the absence of glacial cirques and the scarcity of large moraines. However, the prevalence of groundwater flow and chemical dissolution has favoured the preservation of glacial landforms. Lateral and frontal moraines show three main glacial stages and other minor glacier stabilization phases, with the paleo-ELA oscillating between 1650 and 1760 m. Moraines are combined with depressions and sinks resulting from subglacial karstic drainage. This convergence of forms and processes is an exception in the Cantabrian Mountains, where postglacial erosion has usually eroded the frontal moraines and the proglacial sediments. In the case of the Sierra de los Grajos, despite the underground drainage and preservation of many glacial deposits on karstic landforms, an outwash-plain was formed. These proglacial sediments and others from non-karstified areas filled the depressions of the preglacial terrain located at their edges. The main glaciokarstic landforms have been mapped and a sedimentological analysis of the outwash plain was made in order to reconstruct the glacial dynamics of this area. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experiences as a mountaineering Sierran geomorphologist.

This study is a first in a Saharan region. Following a collaboration between soil scientists and geomorphologists a geomorphological mapping was realized. This work aims to understand the evolution of Saharan soils .The result we obtained demonstrated the presence of five geomorphological soil level. Each level and defined as soil with special chemical, physical and genetic characteristic. [ABSTRACT FROM AUTHOR]

In recent years technological developments have revolutionized our ability to collect data in geomorphology. Enhanced data collection not only enables us to provide deeper answers to a wider range of fundamental questions about the Earth's surface, but also encourages us to pose new questions. This paper considers in more detail the relationships between science, technology and the development of geomorphological tools and techniques, reviews the spectrum of tools and techniques now available to geomorphologists, and critically assesses what impact ‘new technologies’ are having on geomorphology. It focuses on the role of technology in biogeomorphology and weathering research, and how it is advancing theoretical, empirical and applied dimensions of these growing sub-fields of geomorphology. Five areas of important technological development are reviewed: remote sensing, dating, geophysical techniques, field and laboratory based analysis and sensing of physical and chemical characteristics, and field and laboratory based analysis of biological properties. There is good evidence that, taken together, technological developments are revolutionizing geomorphology through opening the doors to better cross-scalar investigations, blurring the boundaries between laboratory, field and computer model, and facilitating cross-disciplinary and democratized research. [ABSTRACT FROM AUTHOR]

Geomorphology plays a pivotal role in linking the traditional subdisciplines of physical geography. This is because geomorphological processes are influenced by climate, and geomorphology in turn strongly controls land surface hydrology and ecosystems. This review assesses the current status of geomorphology in South Africa. Six subfields are identified, viz. fluvial geomorphology, glacial and periglacial geomorphology, rock weathering, arid and semi-arid geomorphology, coastal and estuarine geomorphology, and applied geomorphology. The status of each is critically assessed. Studies in the different subfields reveal progress not only at the site-scale, but that such studies are also commonly set within a wider regional to global context. Regional research is well connected to contemporary global debates. Two of these debates are of particular significance. Firstly, cosmogenic dating techniques can be used to evaluate the age of land surfaces. Geomorphological research in South Africa has begun to utilize this technique to this end. Secondly, geomorphological knowledge can be practically applied. This includes fluvial geomorphology (managing the dynamics of river and wetland systems), rock weathering (preservation of San art and monuments), and coastal and estuarine geomorphology (understanding coastal responses to global sea-level rise) as well as broader environmental management issues. Geomorphology and geomorphological processes are critically important to issues impacting on South Africa in the twenty-first century. These include climate and environmental change, food and water security, and sustainable abiotic resource conservation and management. South African geomorphologists and their international collaborators can, and should, be at the heart of many of these contemporary debates. [ABSTRACT FROM PUBLISHER]

Understanding morphodynamic processes and their controls has long been the focus of geomorphologists. Studying channel adjustments with respect to fractional sediment (clay + silt, sand, and gravel) is often hampered by the lack of both long-term measurements and detailed information about their transport. Taking advantage of a 20-year detailed dataset from Goodwin Creek, Mississippi (USA), this study explores temporal patterns of fractional sediment dynamics in two consecutive reaches with contrasting geomorphic settings: one with tributaries and a gravel-dominated bed (Middle Reach) and the other without tributaries and a sand-dominated bed (Lower Reach). Floods associated with large erosional/depositional events were examined to evaluate their geomorphic effectiveness. Though large deposits in fine sediment were predominant within the two reaches, both reaches exhibited contrasting behaviors of sand and gravel dynamics. We noted that substantial changes in fine sediment storage tend to occur during medium, long-duration flood events. Their effectiveness, however, depends strongly on the stability of the riverbank and the conditions of near-bank sediment storage inherited from historical flows. Among the three sediment fractions, only sand exhibited high activities during peak events ≥1.4-year flood. The presence of high proportions of sand in bed materials prevented the development of a clear relationship between peak flow and gravel dynamics. The channel's geomorphic settings, hence, sediment supply, have been found to control the variations in fractional sediment dynamics. Episodic sediment supplies from upstream, tributaries, and banks determined the changes in fine sediment storage, whereas changes in sand and gravel storage were related to their availability within the reaches. In Goodwin Creek, the sustainable delivery of sand from upstream enhanced bed mobility from the Middle Reach downstream to the Lower Reach creating opposite, albeit small, gravel dynamics. Though sediment control measures significantly reduced sediment supply during the 1990s, the streambanks of the Lower Reach were found to be a major source of fines, contributing as much fines as that produced by 84 % of the watershed area. This result has direct implications for the management of similar reaches in the Bluff Hills region, Mississippi. The findings highlight the importance of considering variations in sediment storage when predicting likely adjustments of channels with erodible banks based on hydraulic thresholds. • Channel adjustments with respect to fractional sediment are assessed using unique datasets. • Medium, long-duration floods affect morphodynamics of rivers with erodible banks. • The geomorphic effectiveness of floods depends strongly on historical sediment storage. • Fractional sediment dynamics linked to channel's characteristics and sediment supply. [ABSTRACT FROM AUTHOR]

• Sediment budgets are fundamentally important for planetary geomorphology. • Two methods, remote sensing and in-situ, used on Earth, but only the former on Mars. • What is effect of only one available method without a second for validation on Mars? • Terrestrial analog case study revealed 3 to 138 relative % difference between methods. • Many more analog studies will improve sediment budgets on Mars, other planets. Sediment budgets are fundamentally important for planetary science. However, only one primary method, based on remote sensing, is currently available for determining extraterrestrial sediment budgets. For determining sediment budgets on Earth, both in-situ and remote sensing methods are available. Despite the widespread use of the two methods, there has been surprisingly little research on how well the sediment budgets produced by these two approaches reconcile with one another, which highlights the lack of quantitative understanding of errors for sediment budgets measured with remote sensing in planetary research. Therefore, there is a general need to expand our knowledge of sediment budgets. Here we use a background review and analog case study of an aeolian dunefield in Grand Canyon, Earth to frame a path forward for addressing shortcomings of remote sensing sediment budgets on Mars. We estimate a 53% percent difference in the sediment budget determined with remote sensing relative to in-situ methods for a simple endmember scenario of a dunefield within a unimodal wind directional regime and no external sediment supply. However, when we incorporated key sources of uncertainty in remote sensing change detection following methods commonly used by geomorphologists on Earth, the estimates of sediment budget differences relative to the in-situ method spanned a much larger range, from 3% to 138%. Our case study also suggests that sediment budget errors could be much larger under more complex wind direction, sediment supply, and physiographic settings, and that variability in those landscape characteristics might be used to better estimate errors for dunefield sediment budgets. We conclude that by comparing sediment budgets derived from in-situ measurements of sediment fluxes and from remote sensing measurements at many more analog sites on Earth, the aeolian research community, and the geomorphology discipline, could gain an understanding of the errors of the remote sensing method, which is used by investigators on other planetary bodies such as Mars. This could improve the ability to quantify sediment budgets on Mars – and, in the future, other planetary environments where high-resolution topographic data are available – as well as directly improve our ability to interpret extraterrestrial landscape evolution related to climate, weather, and geologic history. [ABSTRACT FROM AUTHOR]

New Palaeolithic sites are rare for MIS 11 to 9 in Eurasia. The discovery and the excavation of a large new site in 2012 at Etricourt-Manancourt (Somme, France) is an exceptional event. In 2010, a Palaeolithic evaluation was undertaken at a future retention basin by Emilie Goval on 170,000 square metres. The evaluation produced many flint artefacts, demonstrating the existence of at least two important Middle Palaeolithic sites. In 2012, an excavation on one of the sites was conducted by David Hérisson over 6 months and covering 4500 square metres. This excavation was undertaken by a multidisciplinary scientific team, including prehistorians and geomorphologists. This allows us to apply a reliable chronostratigraphic approach based on the analysis of the Glacial-interglacial successions. Five in situ Palaeolithic occupations have been excavated, dating from 330 to 70 ka. The youngest occupation dates from 70 to 80 ka (Weichselian) and corresponds to a recent phase of the Middle Palaeolithic. The next two layers belong to the Early Middle Palaeolithic, between 190 and 240 ka (Saalian). Finally, the two oldest layers have dates between 330 and 280 ka (Saalian) and belong to the Lower Palaeolithic. In addition to the archaeology, the sedimentary sequence is very thick (11 m high) and presents for the first time in Northern France a detailed record of the three last interglacial–glacial cycles. This paper presents the first archaeological and chronostratigraphic results of the excavation of Etricourt-Manancourt and its input with high resolution data to discuss behavioural changes occurring at the end of the Lower Palaeolithic and the onset of the Middle Palaeolithic. [ABSTRACT FROM AUTHOR]

The sites of two field experiments based on micro-erosion metering, one in UK the other in New Zealand, were independently revisited respectively 33 and 17 years after installation. At both sites natural weathering and erosion processes had been inadvertently interrupted by the experimental works, leading to the development of new microscale landforms. These are interpreted in the context of modifications of the controls on weathering processes, leading to enhanced understanding of the processes themselves. This has lessons for the geomorphologist in maintaining a long-term watching brief over former experimental sites, lest some unintended and potentially beneficial outcome has ensued. This theme is embraced by the Law of Unintended Consequences. [ABSTRACT FROM AUTHOR]

Lesotho provides a unique context for palaeoclimatic research. The small country is entirely landlocked by South Africa, yet has considerable variation in topography, climate, and associated vegetation over an approximate east–west transect. The region has been of archaeological interest for over a century, and hosts many Early to Late Stone Age sites with occupation preceding 80 000 years before present. The eastern Lesotho highlands are of interest to periglacial and glacial geomorphologists because of their well-preserved relict landforms and contentious evidence for permafrost and niche glaciation during the late Quaternary. However, continuous proxy records for palaeoenvironmental reconstructions for Lesotho are scarce and hampered by a range of methodological shortfalls. These challenges include uncertain ages, poor sampling resolution, and proxies extracted from archaeological excavations for which there may be bias in selection. Inferences on palaeoclimates are thus based predominantly on archaeological and palaeogeomorphological evidence for discrete periods during the late Quaternary. This review paper presents a more detailed multidisciplinary synthesis of late Quaternary conditions in Lesotho. We simultaneously considered the varying data that contribute to the under-studied palaeoenvironmental record for southern Africa. The collective palaeoenvironmental data for eastern Lesotho were shown to be relatively contradictory, with considerable variations in contemporaneous palaeoclimatic conditions within the study area. We argue that although methodological challenges may contribute to this variation, the marked changes in topography result in contrasting late Quaternary palaeoenvironments. Such environments are characterised by similar contrasting microclimates and niche ecologies as are witnessed in the contemporary landscape. These spatial variations within a relatively small landlocked country are of importance in understanding broader southern African palaeoenvironmental change. [ABSTRACT FROM AUTHOR]

An advanced SAR interferometric analysis has been combined with a methodology for the automatic classification of radar reflectors phase histories to interpret slope-failure kinematics and trend of displacements of slow-moving landslides. To accomplish this goal, the large dataset of radar images, acquired in more than 20 years by the two European Space Agency (ESA) missions ERS-1/2 and ENVISAT, was exploited. The analysis was performed over the northern sector of Island of Malta (central Mediterranean Sea), where extensive landslides occur. The study was assisted by field surveys and with the analysis of existing thematic maps and landslide inventories. The outcomes allowed definition of a model capable of describing the geomorphological evolution of slow-moving landslides, providing a key for interpreting such phenomena that, due to their slowness, are usually scarcely investigated. [ABSTRACT FROM AUTHOR]

One of the most prominent American geomorphologists, Neil E. Salisbury, passed away in May 2015. This paper examines his legacy in geomorphology over the course of his career, and hopefully will be seen as honoring his memory. [ABSTRACT FROM AUTHOR]

As geomorphologists embrace ever more sophisticated theoretical frameworks that shift from simple notions of evolution towards single steady equilibria to recognise the possibility of multiple response pathways and outcomes, morphodynamic modellers are facing the problem of how to keep track of an ever-greater number of system feedbacks. Within coastal geomorphology, capturing these feedbacks is critically important, especially as the focus of activity shifts from reductionist models founded on sediment transport fundamentals to more synthesist ones intended to resolve emergent behaviours at decadal to centennial scales. This paper addresses the challenge of mapping the feedback structure of processes controlling geomorphic system behaviour with reference to illustrative applications of Causal Loop Analysis at two study cases: (1) the erosion–accretion behaviour of graded (mixed) sediment beds, and (2) the local alongshore sediment fluxes of sand-rich shorelines. These case study examples are chosen on account of their central role in the quantitative modelling of geomorphological futures and as they illustrate different types of causation. Causal loop diagrams, a form of directed graph, are used to distil the feedback structure to reveal, in advance of more quantitative modelling, multi-response pathways and multiple outcomes. In the case of graded sediment bed, up to three different outcomes (no response, and two disequilibrium states) can be derived from a simple qualitative stability analysis. For the sand-rich local shoreline behaviour case, two fundamentally different responses of the shoreline (diffusive and anti-diffusive), triggered by small changes of the shoreline cross-shore position, can be inferred purely through analysis of the causal pathways. Explicit depiction of feedback-structure diagrams is beneficial when developing numerical models to explore coastal morphological futures. By explicitly mapping the feedbacks included and neglected within a model, the modeller can readily assess if critical feedback loops are included. [ABSTRACT FROM AUTHOR]

This special issue honors the contributions of William L. Graf to geomorphology and river science. A hallmark of Will's work over the course of his career has been a focus on the natural and human structuring of river systems. More broadly, Will has been an innovator and leader who has shaped the way in which geomorphologists conduct research. Through his work, he has made fundamental contributions to basic fluvial theory, to the understanding of human impacts on river systems, and to policy-relevant science. He has demonstrated by example how to pursue policy-relevant science and to participate in science-based policy formulation. His contributions to river science can be classified into several themes: (1) the hydrology and geomorphology of suburban drainage systems, (2) riparian vegetation and river systems, (3) the spatial structure and dynamics of incised channels, (4) the dynamics of dryland river systems, (5) heavy metals in river systems, (6) dams and dam removal, and (7) water and public policy. The papers in this special issue reflect many aspects of these themes and address topics related to (1) the understanding of rivers and other geomorphic systems in the midst of dynamic physical change, (2) human influences on geomorphic processes, (3) the intersection of geomorphology and public policy, and (4) the fusion of geomorphic analysis and GIScience. [ABSTRACT FROM AUTHOR]

Landscape illustration, a core visualization technique for field geologists and geomorphologists, employs the parsimonious use of linework to represent surface structure in a straightforward and intuitive manner. Under the rubric of non-photorealistic rendering ( NPR), automated procedures in this vein render silhouettes and creases to represent, respectively, view-dependent and view-independent landscape features. This article presents two algorithms and implementations for rendering silhouettes from adaptive tessellations of point-normal ( PN) triangles at speeds approaching those suitable for animation. PN triangles use cubic polynomial models to provide a surface that appears smooth at any required resolution. The first algorithm, drawing on standard silhouette detection techniques in surface meshes, builds object space facet adjacencies and image space pixel adjacencies in the graphics pipeline following adaptive tessellation. The second makes exclusive use of image space analysis without referencing the underlying scene world geometry. Other than initial pre-processing operations, recent advances in the OpenGL API allow implementations for both algorithms to be hosted entirely on the graphics processing unit ( GPU), eliminating slowdowns through data transfer across the system memory bus. We show that both algorithms provide viable paths to real-time animation of pen and ink style landscape illustrations but that the second demonstrates superior performance over the first. [ABSTRACT FROM AUTHOR]

Among the anthropogenic topographic signatures on Earth, open-pit mines are of great importance. Mining is of interest to geomorphologists and environmental researchers because of its implication in geomorphic hazards and processes. In addition, open-pit mines and quarries are considered the most dangerous industrial sector, with injuries and accidents occurring in numerous countries. Their fast, accurate and low-cost investigation, therefore, represents a challenge for the Earth science community. The purpose of this work is to characterise the open-pit mining features using high-resolution topography and a recently published landscape metric, the Slope Local Length of Auto-Correlation (SLLAC) ( Sofia et al., 2014 ). As novel steps, aside from the correlation length, the terrace’s orientation is also calculated, and a simple empirical model to derive the percentage of artificial surfaces is tested. The research focuses on two main case studies of iron mines, both located in the Beijing district (P.R. China). The main topographic information (Digital Surface Models, DSMs) was derived using an Unmanned Aerial Vehicle (UAV) and the Structure from Motion (SfM) photogrammetric technique. The results underline the effectiveness of the adopted methodologies and survey techniques in the characterisation of the main mine’s geomorphic features. Thanks to the SLLAC, the terraced area given by open-cast/open-pit mining for iron extraction is automatically depicted, thus, allowing researchers to quickly estimate the surface covered by the open-pit. This information could be used as a starting point for future research (i) given the availability of multi-temporal surveys to track the changes in the extent of the mine; (ii) to relate the extent of the mines to the amount of processes in the area (e.g. pollution, erosion, etc.), and to (iii) combine the two points, and analyse the effects of the change related to changes in erosion. The analysis of the correlation length orientation also allows researchers to identify the terrace’s orientation and to understand the shape of the open-pit area. The tectonic environment and history, or inheritance, of a given slope can determine if and how it fails, and the orientation of the topographic surface or excavation face, with respect to geologic features, is of major significance. Therefore, the proposed approach can provide a basis for a large-scale and low-cost topographic survey for sustainable environmental planning and, for example, for the mitigation of environmental anthropogenic impacts due to mining. [ABSTRACT FROM AUTHOR]

Planetary geomorphology is the study of extraterrestrial landscapes. In recognition of the promise for productive interaction between terrestrial and planetary geomorphologists, the 45th annual Binghamton Geomorphology Symposium (BGS) focused on Planetary Geomorphology. The aim of the symposium was to bring planetary and terrestrial geomorphologists together for symbiotic and synthetic interactions that would enrich both subdisciplines. In acknowledgment of the crucial role of terrestrial field work in planetary geomorphology and of the BGS tradition, the symposium began with a field trip to the Appalachian Mountains, followed by a dinner talk of recent results from the Mars Surface Laboratory. On Saturday and Sunday, the symposium was organized around major themes in planetary geomorphology, starting with the geomorphic processes that are most common in our Solar System—impact cratering, tectonism, volcanism—to set the stage for other geomorphic processes, including aeolian, fluvial, lacustrine, and glacial/polar. On Saturday evening, the banquet talk provided an historical overview of planetary geomorphology, including its roots in the terrestrial geosciences. The symposium concluded with a full-afternoon tutorial on planetary geomorphologic datasets. This special issue of Geomorphology consists of papers by invited authors from the 2014 BGS, and this introduction provides some context for these papers. [ABSTRACT FROM AUTHOR]

Braided rivers have been intensively analyzed mostly by geomorphologists. In the present study the approach to recognize braided channel types and effects with the special emphasis on flow partitioning has been applied. It is assumed that each braided channel represents the reach which is initiated with dividing of the single channel and completed below the confluence of the total multiplicity of channels. Proposed indices of braided channel structure and water discharges ratio which have been proposed and applied to 200 braided reaches of 40 rivers in Russia, China, and the USA enable the description of the origin and types of the observed rivers and further analysis of hydrological effects of braided channels. The latter represent physical, hydrochemical, and ecological conditions of stream along braided reaches caused by flow distribution among branches in relation to braiding intensity. Structure and braided channel pattern types impact on hydraulics, sediment transport, water temperatures, and stream communities are of primary interest in the present study. [ABSTRACT FROM AUTHOR]

Erosion surfaces at the top of mountain ranges have suggested to geomorphologists that the Earth's crust can undergo rapid pulses of uplift during which rates of denudation fail to balance with rates of crustal uplift, thereby preserving much of the initial plateau topography as it rises to greater elevations. Here we analyze a regionally extensive population of mappable planar surfaces, which crown several major, tectonically active sierras of the inner south-eastern Betic Cordillera, SE Spain. Based on a synthesis of long-term landscape evolution involving landform reconnaissance, DEM-based morphometric analysis, structural geology, sediment provenance analysis, and field stratigraphy, we conclude that the summit surfaces are a mosaic of discrete, post-orogenic erosion surfaces that each developed in relation to Mediterranean marine base levels at a time when the sierras formed a series of low-elevation islands. They are not, therefore, fragments of a once regionally continuous paleoplain. The summit surfaces were partly the result of shallow-angle detachment faulting during the middle Miocene in response to lithospheric slab detachment. Where evidence exists that the resulting low-relief topography was reworked by marine abrasion during the Tortonian sea-level rise, the terminal age of the surfaces is latest Miocene. Age-bracketing based on stratigraphic correlations among the many depocentres of the region and on published thermochronological data indicates that some erosion surfaces locally formed in less than 3 million years (~ 8 Ma–5.7 Ma). They were subsequently uplifted to their current elevations (1.7 to > 2 km) by Pliocene to Quaternary neotectonics in at least two major pulses. [ABSTRACT FROM AUTHOR]