Despite the importance of bedforms (e.g., ripples, dunes) to sediment transport, the details of sediment transport on a sub-bedform scale are poorly understood. This paper investigates sediment transport in the downstream and cross-stream directions over bedforms with straight crests. We find that the patterns of bedload transport are highly variable on the sub-bedform scale, which is important for our understanding of the evolution of bedforms with complex crest geometries.

We examine differences in glacier extent in the Olympic Mountains, USA, where modern precipitation in east-facing valleys is only 50 % of that in west-facing valleys. During the Last Glacial Period, there were very small glaciers in the east and very large glaciers in the west. We use climate data and glacier models to show that the modern spatial pattern of precipitation is likely to have been similar during the past glaciation and may be sufficient to explain the asymmetry of glacier extent.

We compare models of erosion against a global compilation of long-term erosion rates in order to find and interpret best-fit parameters using an iterative search. We find global signals among exponents which control the relationship between erosion rate and slope, as well as other parameters which are common in long-term erosion modelling. Finally, we analyse the global variability in parameters and find a correlation between precipitation and coefficients for optimised models.

We combined data from satellite images with data measured from a kayak in order to understand the propagation of fine sediment in the Vjosa River. We were able to find some storm-activated and some permanent sources of sediment. We also estimated how much fine sediment is carried into the Adriatic Sea by the Vjosa River: approximately 2.5 Mt per year, which matches previous findings. With our work, we hope to show the potential of open-access satellite images.

Quantitative knowledge of water availability on high mountain rock slopes is very limited. We use a numerical model and field measurements to estimate the water balance at a steep rock wall site. We show that snowmelt is the main source of water at elevations >3600 m and that snowpack hydrology and sublimation are key factors. The new information presented here can be used to improve the understanding of thermal, hydrogeological, and mechanical processes on steep mountain rock slopes.

Preservation bias often hampers the extraction of sea level changes from the stratigraphic record. In this contribution, we use a forward stratigraphic model to build three synthetic subtropical fringing reefs for a site in southwestern Madagascar (Indian Ocean). Each of the three synthetic reefs represents a different ice sheet melt scenario for the Pleistocene. We then evaluate each resultant reef sequence against the observed stratigraphic record.

Floods draining beneath an ice cap are hazardous events that generate six different short- or long-lasting types of seismic signals. We use these signals to see the collapse of the ice once the water has left the lake, the propagation of the flood front to the terminus, hydrothermal explosions and boiling in the bedrock beneath the drained lake, and increased water flow at rapids in the glacial river. We can thus track the flood and assess the associated hazards better in future flooding events.

We investigated the influence of sediment transport modes on the formation of bedforms using theoretical analysis. The results of the theoretical analysis were verified with published data of plane beds obtained by fieldwork and laboratory experiments. We found that suspended sand particles can promote the formation of plane beds on a fine-grained bed, which suggests that the presence of suspended particles suppresses the development of dunes under submarine sediment-laden gravity currents.

Rivers can cut into rocks, and their strength modulates the river's erosion rates. Yet, which properties of the rock control its response to erosive action is poorly understood. Here, we describe parallel experiments to measure rock erosion rates under fluvial impact erosion and the rock's geotechnical properties such as fracture strength, elasticity, and density. Erosion rates vary over a factor of a million between different rock types. We use the data to improve current theory.

We measured rock strength and amount of fracturing in the two different rock types, sandstones and carbonates, in Last Chance Canyon, New Mexico, USA. Where there is more carbonate bedrock, hills and channels steepen in Last Chance Canyon. This is because the carbonate-type bedrock tends to be more thickly bedded, is less fractured, and is stronger. The carbonate bedrock produces larger boulders than the sandstone bedrock, which can protect the more fractured sandstone bedrock from erosion.