We have derived a simple solution to the stream power law equation governing the erosion of rapidly uplifting tectonic areas assuming that rainfall varies as a periodic function of time. We show that the erosional response of this forcing is characterized by an amplification of the resulting erosional flux variations as well as a time lag. We show how this time lag can be important in interpreting several geological observations.

Rivers transport sediment from mountains to coast, but on the way sediment is trapped and re-eroded multiple times. We looked at Rhine river sediments to see if they preserve evidence of how geomorphic variables have changed over time. We found that measured signals potentially relate to water level and river management practices. These relationships can be treated as hypotheses to guide further research, and our statistical approach will increase the utility of research in this field.

In this work we present DeltaRCM, a reduced-complexity model for river delta formation. It is a rule-based cellular morphodynamic model, in contrast to reductionist models based on detailed computational fluid dynamics. DeltaRCM is able to resolve channel dynamics and to produce stratigraphy. We also explain the meaning of complexity reduction, especially the essential processes to be included in modeling deltas.

In this work we assess the flow-routing component (FlowRCM) of our delta formation model, DeltaRCM. We found that with the level of complexity reduction, FlowRCM is able to produce channel network-scale hydrodynamic details, which provide further insights into the connection between delta flow structures and the morphodynamic outcome.

The saltation-abrasion model captures bedrock incision due stones striking bedrock. We present the Macro-Roughness-based Saltation-Abrasion-Alluviation (MRSAA) model, which tracks spatiotemporal variation of both bedload and alluvial thickness. It captures migrating waves of incision upstream and alluviation downstream. We apply it to incision problems not captured by saltation-abrasion, including the response to alluviation and stripping, and a simplified graben with uplift and subsidence.

We use ice-penetrating-radar data to identify a laterally continuous, gently sloping topographic block, comprising two surfaces separated by a distinct break in slope, preserved beneath the Institute and Möller ice streams, West Antarctica. We interpret these features as extensive erosion surfaces, showing that ancient (pre-glacial) surfaces can be preserved at low elevations beneath ice sheets. Different erosion regimes (e.g. fluvial and marine) may have formed these surfaces.

Within a landscape evolution model operating over geologic timescales, this work evaluates how different assumptions and levels of complexity for modeling glacier flow impact the pattern and amount of glacial erosion. Compared to those in colder climates, modeled glaciers in warmer and wetter climates are more sensitive to the choice of glacier flow model. Differences between landscapes evolved with different glacier flow models are intensified over multiple cycles.

Steeper landscapes tend to erode faster. In this study, we also find that sediment produced on steeper landscapes is coarser. Soils are coarser because fragments spend less time in the soil so are less exposed to processes that can break them down. Change in sediment sources impact the sediment transported by rivers: rivers transport sediment up to cobble size in low-slope, soil-mantled areas; they transport much coarser sediment (including boulders supplied from landslides) in the steep areas.