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This study presents a novel CNN approach for detecting instream large wood in rivers, addressing the need for flexible monitoring methods that can be used on a variety of data sources. Leveraging a database of 15,228 fully labeled images, our model achieved a 67 % weighted mean average precision. Fine-tuning parameters and sampling techniques offer potential for further performance enhancement of more than 10 % in certain cases, promising valuable insights for ecosystem management.

In order to interpret the formation processes of subsurface salt wedges and polygonal patterned grounds from the northern Atacama Desert, we present a multi-methodological approach. Due to the high salt content of the wedges, we suggest that their formation is dominated by subsurface salt dynamics requiring moisture. We assume that the climatic conditions during the wedge growth were slightly wetter than today, offering the potential to use the wedges as palaeoclimate archives.

Loose grains travel farther after a fire because no vegetation is left to stop them. This matters since loose grains at the base of a slope can turn into a debris flow if it rains. To find if grass growing back after a fire had different impacts on grains of different sizes on slopes of different steepness, we dropped thousands of natural grains and measured how far they went. Large grains went farther 7 months after the fire than 11 months after, and small grain movement didn’t change much.

Fluvial terraces and alluvial fans in the Toro Basin, NW Argentina record river evolution and global climate cycles over time. Landform dating reveals lower-frequency climate cycles (100-kyr) preserved downstream and higher-frequency cycles (21/40-kyr) upstream, supporting theoretical predications that longer rivers filter out higher-frequency climate signals. This finding improves our understanding of the spatial distribution of sedimentary paleoclimate records within landscapes.

Using computational fluid dynamics, we analyze the error trends of an analytical shear stress distribution model used to drive aeolian transport for coastal dunes which are an important line of defense against storm related flooding hazards. We find that compared to numerical simulations, the analytical model results in a net overprediction of the landward migration rate. Additionally, two data-driven approaches are proposed for reducing the error while maintaining computational efficiency.

To explore the pattern formed by rivers as they crisscross the land, we developed a way to measure how these patterns vary, from straight to complex, winding paths. We discovered that the rivers’ degree of complexity depends on how the river slope changes downstream. Although this is strange, i.e., why would changes in slope affect twists of a river in map-view? We show that this dependency is almost inevitable, and that the complexity could signify how arid the climate is or used to be.

Rock glaciers are comparatively climate-resilient coarse-debris permafrost landforms. We estimate the energy budget of the seasonally thawing active layer (AL) of rock glacier Murtèl (Swiss Alps) based on a novel sub-surface sensor array. In the coarse-blocky AL during the thaw season, heat is transferred by thermal radiation and air convection. The ground heat flux is largely used to melt ground ice in the AL that protects to some degree the permafrost body beneath.

This paper answers questions about potential climate-induced changes to the storminess along the U.S. east coast and the impact of storms on U.S. east coast beaches. We found that the number of storms that occur annually have not increased over time, but storm strength has increased, albeit modestly, over time. There is also variation in these patterns geographically. Finally, the cumulative impact of successive and large storms can impact beaches for up to 10 years.

At the evocation of ‘icy landscapes’, Africa is not the first place that comes to mind. The modern relief of Southern Africa is generally considered as resulting from uplift and counteracting erosion. We show that many modern reliefs of this region are fossil glacial landscapes tied to an ice age that occurred 300 million years ago: striated pavements, valleys, fjords. We emphasise how these landscapes have escaped being erased for hundreds of millions of years, generally considered improbable.

This paper shows how glacier-related sediment supply changes in response to earthquakes and climate warming at a catchment in the eastern Himalayas using several decades of aerial imagery and high-resolution UAV data. The results highlight the importance of debris-flow-driven extreme sediment delivery on landscape change in High Mountain Asia that have undergone substantial climate warming. This study is helpful for a better understanding of future risk of periglacial debris flows.

The summertime thaw depth of permanently frozen ground (active layer thickness, ALT) is of critical importance for natural hazard management (e.g. rock avalanches), construction (foundation stability) and greenhouse gas emissions (decomposition rates) in permafrost regions. We presented the first analytical heat transport model for simulating ALT on borehole scale. Our results show that the ALT will likely increase by more than 50 % until 2050 at 3000 m a.s.l. in the European Alps.

Fine sediment grains in freshwater can cohere into faster settling particles called flocs, but floc settling velocity theory has not been fully validated. Data from the Wax Lake Delta verify a semi-empirical model relying on turbulence and geochemical factors. We showed that the representative grain diameter within flocs relies on floc structure and that floc internal flow follows a model in which flocs consist of permeable grain clusters, thus improving a physics-based settling velocity model.

Faceted topographies are impressing footprints of active tectonics in geomorphology. This paper investigates the evolution of faceted topographies at normal faults and its interaction with the river network theoretically and numerically. As a main result beyond several relations for the the geometry of facets, the horizontal displacement associated to normal faults is crucial for the dissection of initially polygonal facets into triangular facets bounded by almost parallel rivers.

Sea level was significantly higher during the Pliocene Epoch, around three million years ago. The present-day elevations of shorelines that formed in the past provide data constraint on the extent of ice sheet melt and the global sea level response under warm Pliocene conditions. In this study, we identify ten escarpments that formed from wavecut erosion during Pliocene times and compare their elevations with model predictions of solid Earth deformation processes to estimate past sea level.

Geomorphic indices were used to understand topographic changes in response to tectonic activity. We applied indices to evaluate the relative tectonic intensity of Ulsan Fault Zone, one of the most active fault zones in Korea. We divided the UFZ into five segments based on spatial variation in intensity. We modelled the landscape evolution of study area and interpreted tectono-geomorphic history that the northern part of the UFZ experienced asymmetric uplift, while the southern part did not.

Sediments deposited within river channels form the stratigraphic record, which has been used to interpret tectonic events, basin subsidence, and changes in precipitation long after ancient mountain chains have eroded away. Our work combines methods for estimating gravel fining with a landscape evolution model in order to analyze the grain size preserved within the stratigraphic record with greater complexity (e.g. considering topography and channel dynamics) than past approaches.

Massive rock slope failures are a significant alpine hazard and change the earth´s surface. Therefore, we must understand what controls the preparation of such events. By correlating four years of slope displacements with meteorological and seismic data, we found that water from rain and snowmelt is the most important driver. Our approach is applicable to similar sites and indicates, where future climatic changes, e.g. in rain intensity and frequency, may alter the preparation of slope failure.

On Earth, glacial cirques are a type of landform eroded by wet-based glaciers, which are glaciers with liquid water at the base of a glacier. While select alcoves have been interpreted as glacial cirques on Mars, we map and assess a large-scale population of ~2000 alcoves as potential cirques in the northern mid-latitudes of Mars. From physical measurements and characteristics, we find 386 cirque-like alcoves. This extends our knowledge of the extent and type of glaciation in the region.

The rates at which rivers erode their bed can be used to interpret the geologic history of a region. However, these rates depend significantly on the time window over which you measure. We use multiple dating methods to determine an incision rate on the San Juan River and compare it to regional rates with longer timescales. We demonstrate how specific geologic events, such as cutoffs of bedrock meander bends, are likely to preserve material we can date but also bias the rates we measure.

We have developed a new numerical model to represent the formation of ferricretes which are iron-rich, hard layers found in soils and at the surface of the Earth. We assume that the formation mechanism implies variations in the height of the water table and that the hardening rate is proportional to precipitation. The model allows us to quantify the potential feedbacks they generate on the surface topography and the thickness of the regolith/soil layer.

The central South Tian Shan displays a complex river pattern spatially. We choose the transition zone in between and analyse topographic and fluvial metrics along the river profile. Considering the river patterns and the timing constraints, we suggest that the river patterns were triggered by a big capture event, potentially affected by both tectonic and climate factors. This conclusion underlines the importance of local contingent factors in driving drainage development.