Impact of change in erosion rate and landscape steepness on hillslope and fluvial sediments grain size in the Feather River basin (Sierra Nevada, California)
Summary: 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.
Earth Surf. Dynam., 3, 201-222, doi:10.5194/esurf-3-201-2015, 2015
Numerical modelling of glacial lake outburst floods using physically based dam-breach models
Earth Surf. Dynam., 3, 171-199, doi:10.5194/esurf-3-171-2015, 2015
Ice flow models and glacial erosion over multiple glacial–interglacial cycles
Summary: 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.
Earth Surf. Dynam., 3, 153-170, doi:10.5194/esurf-3-153-2015, 2015
Ancient pre-glacial erosion surfaces preserved beneath the West Antarctic Ice Sheet
Summary: 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.
Earth Surf. Dynam., 3, 139-152, doi:10.5194/esurf-3-139-2015, 2015
Macro-roughness model of bedrock–alluvial river morphodynamics
Summary: 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.
Earth Surf. Dynam., 3, 113-138, doi:10.5194/esurf-3-113-2015, 2015
The role of velocity, pressure, and bed stress fluctuations in bed load transport over bed forms: numerical simulation downstream of a backward-facing step
Earth Surf. Dynam., 3, 105-112, doi:10.5194/esurf-3-105-2015, 2015
A reduced-complexity model for river delta formation – Part 2: Assessment of the flow routing scheme
Summary: 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.
Earth Surf. Dynam., 3, 87-104, doi:10.5194/esurf-3-87-2015, 2015
A reduced-complexity model for river delta formation – Part 1: Modeling deltas with channel dynamics
Summary: 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.
Earth Surf. Dynam., 3, 67-86, doi:10.5194/esurf-3-67-2015, 2015