We used high-resolution topography collected over 4 years to investigate how two watersheds in Colorado responded to the June 2012 High Park Fire and an extreme flood in September 2013. After the fire, sediment was eroded from the hillslopes and deposited in valley bottoms, and the large flood eroded much of this deposited sediment. Patterns of erosion and deposition were related to landscape characteristics, burn severity, and rainfall, which may inform future post-fire treatment strategies.

We propose a new algorithm to solve the problem of flow routing across local depressions in the topography, one of the main computational bottlenecks in landscape evolution models. Our solution is more efficient than the state-of-the-art algorithms, with an optimal linear asymptotic complexity. The algorithm has been designed specifically to be used within landscape evolution models, and also suits more generally the efficient treatment of large digital elevation models.

This research has been conducted to develop the use of passive acoustic monitoring (PAM) for bedload monitoring in rivers. Monitored bedload acoustic signals depend on bedload characteristics (e.g., grain size distribution, fluxes) but are also affected by the environment in which the acoustic waves are propagated. This study focuses on the determination of propagation effects in rivers. An experimental approach has been conducted in several streams to estimate acoustic propagation laws.

A simple model is proposed to improve the sediment concentration monitoring in the large rivers of the Peruvian Amazon from an index concentration sampled in the flow. This powerful tool for optimizing the concentration sampling would allow for detailed uncertainty analysis on the sediment fluxes. It could be coupled with remote sensing and hydrological modeling to serve as a step toward the development of an integrated approach for assessing sediment fluxes in poorly monitored basins.

We used continuous seismic data from two small aperture geophone arrays deployed in the region above Davos in the eastern Swiss Alps to develop a machine learning workflow to automatically identify signals generated by snow avalanches. Our results suggest that the method presented could be used to identify major avalanche periods and highlight the importance of array processing techniques for the automatic classification of avalanches in seismic data.

Typically, we think of a shoreline growing with a smooth line separating the land and the water. If the growth is unstable, however, the land–water front will exhibit a roughness that grows with time. Here we ask whether the growth of deltaic shorelines cab be unstable. Through mathematical analysis we show that growth is unstable when the shoreline is building onto an adverse slope. The length scale of the unstable signal in such a case, however, might be obscured by other geomorphic processes.

Representing the surface of the Earth on an equally spaced grid leads to errors and uncertainties in derived slope and aspect. Using synthetic data, we develop a quality metric that can be used to compare the uncertainties in different datasets. We then apply this method to a real-world lidar dataset, and find that 1 m data have larger error bounds than lower-resolution data. The highest data resolution is not always the best choice – it is important to consider the quality of the data.

Our study reveals that worldwide mean erosion rates on the million-year timescale are very similar to present-day erosion rates in contrast to the majority of the previously published results. Concerning the dependence of erosion on climate, we found that the long-term erosion efficacy of the tropical zone has been about 5 times higher than that of the cold zones, while the erosional efficacy of the present-day arid zone has been as high as that of the temperate zone.

High-resolution digital elevation models (DEMs) can now be acquired using airborne laser scanners. This allows for a detailed analysis of the geometry of landslides. Several large landslides were triggered by Typhoon Talas in Japan in 2011. The comparison of pre- and post-DEMs allowed us to test a method of defining landslide failure surfaces before catastrophic movements. It provides new results about the curvature of the failure surface and the volume expansion of the deposit.

Our findings examine several data inputs for probabilistic regional sea-level rise (SLR) impact predictions. To predict coastal response to SLR, detailed information on the landscape, including elevation, vegetation, and/or level of development, is needed. However, we find that the inherent relationship between elevation and land cover datasets (e.g., beaches tend to be low lying) is used to reduce error in a coastal response to SLR model, suggesting new applications for areas of limited data.

Using data obtained from multiple UAV flights over a debris-covered glacier in the Himalaya between 2013 and 2018, we show that the adjacent moraines erode at rates of up to 16 cm per year, contributing to this debris cover. With retreating ice and resulting instability of moraines, this causes the glacier to cover a narrow zone along the lateral moraines in ever-thicker layers of rocks, resulting in a possible future decrease of local melt.

The concentration of cosmogenic ¹⁰Be is typically measured in the sand fraction of river sediment to estimate catchment-average erosion rates. Using the sand fraction in catchments where the ¹⁰Be concentrations differ per grain size could potentially result in biased erosion rates. In this study we investigated the occurrence and causes of grain size-dependent ¹⁰Be concentrations and identified the types of catchments which are sensitive to biased catchment-average erosion rates.

The effect of buoyancy and bottom slope on the runout and entrainment capacity of experimentally reproduced saline gravity currents is studied. The shape of the current is modified due to the entrainment of ambient water, particularly within the body region. For steep slopes, two opposite mechanisms of mass exchange are identified: the current entrainment of water from the upper surface due to the enhanced friction at the interface and the head feeding by a rear-fed current.

Deep-seated gravitational spreading features are spectacular on Mars on the hillslopes of Valles Marineris, both in terms of landform freshness and size. This paper compares their dimensions and those in terrestrial analogue sites in the Tatra Mountains. Gravitational spreading is thought to be inactive in both locations. We find that the height-to-width ratio, ~0.24, is similar in spite of much larger strain in Valles Marineris. We explore the implications.

Soil erosion, especially in vulnerable conditions such as post-fire landscapes or tilled agricultural soils, is greatly affected by the occurrence of bursts of intense rainfall. These are often set within longer periods of less intense rain. This paper documents the nature of the intensity bursts at two Australian locations and shows that high-resolution rainfall records are required in order to make estimates of the intensity. Hourly rainfall data are not suitable for this task.

We studied and mapped uplifted marine terraces in southern Iran that are part of the Makran subduction zone. Our results show that most exposed terraces were formed in the last 35 000–250 000 years. Based on their altitude and the paleo sea-level, we derive surface uplift rates of 0.05–5 mm yr⁻¹. The marine terraces, tilted with a short wavelength of 20–30 km, indicate a heterogeneous accumulation of deformation in the overriding plate.