Many studies on modeling landform evolution have focused on mountain ranges, while large parts of Earth's surface are quite flat and alluvial plains have been preferred locations for human settlements. Conducting large-scale simulations of fluvial erosion and sediment transport, this study reveals that rivers in a tectonically inactive foreland are much more dynamic than rivers in a mountain range; the local redistribution of deposits in the foreland is the main driver of the dynamics.

This paper proposes a method to estimate thermal diffusivity and its uncertainty over time, at numerous locations and at an unprecedented vertical spatial resolution from soil temperature time series. We validate and apply this method to synthetic and field case studies. The improved quantification of soil thermal properties is a cornerstone for advancing the indirect estimation of the fraction of soil components needed to predict subsurface storage and fluxes of water, carbon, and nutrients.

Himalayan rivers are full of giant boulders that rarely move except during glacial lake outburst floods (GLOFs), which therefore must be important drivers of erosion in the Himalayas. GLOFs are rare, so little is known about their long-term erosional impact. We found that rivers in Nepal have channel geometry that, compared with markers of upstream glaciation, confirm GLOFs as a major control on erosion. This previously unrecognized control should be accounted for in landscape evolution studies.

Climate change is rapidly altering high-alpine landscapes. The formation of new lakes in areas becoming ice free due to glacier retreat is one of the many consequences of this process. Here, we provide an estimate for the number, size, time of emergence, and sediment infill of future glacier lakes that will emerge in the Swiss Alps. We estimate that up to ~ 680 potential lakes could form over the course of the 21st century, with the potential to hold a total water volume of up to ~ 1.16 km³.

A levee-building model is presented to investigate the effects of flood on levee slope and river behaviors. Coarser grains that cause steep levee slopes lead to frequent switchings of river paths, but higher overflow velocity has an opposite effect. High levee slopes lead to more reoccupations of abandoned old river paths than low levee slopes when rivers switch their locations. The study helps us to assess flood hazards with river-path switching.

We mapped and dated 187 earthflows to determine controls on earthflow formation and resulting topographic changes in the Teanaway basin, central Washington State, USA. Using a new relative dating technique and absolute dating, we find that 25 % of earthflows were active in the last ~500 years. Earthflows are lithologically controlled, actively narrow valleys, and increase sediment loads.

To assess the effects of differences in grain-size distribution within debris flows on the morphology of debris-flow fans, fan morphologies were modeled experimentally. Even if debris flows exhibited similar flow properties, their runout distance differed in response to differences in their grain-size distribution. Differences in runout distance were responsible for variations in the direction of the descending flow that resulted in different debris-flow fan morphology.

This paper presents a novel methodology to identify and quantitatively analyze deposition and erosion patterns in ephemeral ponds or in perennial lakes with strong water level fluctuations. We apply this method to unravel the water and sediment balance of Lac Wégnia, a designated Ramsar site in Mali. The study can be a showcase for monitoring Sahelian lakes using remote sensing data, as it sheds light on the actual drivers of change in Sahelian lakes.

We describe the flow of sediment in river channels by replacing the complicated details of the turbulent water with probability arguments. Our major conclusions are that (1) sediment transport can be phrased in terms of the movements of individual sediment grains, (2) transport rates in river channels are inherently uncertain, and (3) sediment transport in rivers is directly analogous to a number of phenomena which we understand relatively well, such as molecules moving in air.

Abrupt changes in tectonic uplift rates induce sharp changes in river profile, called knickpoints. When river erosion depends non-linearly on slope, we develop an analytic model for knickpoint velocity and find the condition of knickpoint merging. Then we develop analytic models that represent the two-directional link between tectonic changes and river profile evolution. The derivation provides new understanding on the links between tectonic changes and river profile evolution.

Erosion is a threat for soils with rainfall as the driving force. The annual rainfall erosivity factor quantifies rainfall impact by analysing high-resolution rainfall time series (~ 5 min). Due to a lack of measuring stations, alternatives for its estimation are analysed in this study. The best results are obtained for regionalisation of the erosivity factor itself. However, the identified minimum of 60-year time series length suggests using rainfall generators as in this study as well.