- Hydrology and Sediment Transport Processes
- Soil erosion and sediment transport
- Landslides and related hazards
- Geology and Paleoclimatology Research
- Geological formations and processes
- Hydrology and Watershed Management Studies
- earthquake and tectonic studies
- Cryospheric studies and observations
- Geological Modeling and Analysis
- Fire effects on ecosystems
- Scientific Computing and Data Management
- Aeolian processes and effects
- Distributed and Parallel Computing Systems
- Geological and Geochemical Analysis
- Flood Risk Assessment and Management
- Computational Physics and Python Applications
- Land Use and Ecosystem Services
- Methane Hydrates and Related Phenomena
- Climate change and permafrost
- Groundwater flow and contamination studies
- Archaeology and Natural History
- 3D Modeling in Geospatial Applications
- Environmental Monitoring and Data Management
- Plant Water Relations and Carbon Dynamics
- Ecology and Vegetation Dynamics Studies
Cooperative Institute for Research in Environmental Sciences
2016-2025
University of Colorado Boulder
2016-2025
University of Colorado System
2004-2023
Sapienza University of Rome
2022
Istituto Nazionale di Fisica Nucleare, Sezione di Milano
2022
Ørsted (Denmark)
2019
University of Michigan
2018
University of Washington
2016
Seattle University
2016
University of Oxford
2001-2011
The longitudinal profiles of bedrock channels are a major component the relief structure mountainous drainage basins and therefore limit elevation peaks ridges. Further, communicate tectonic climatic signals across landscape, thus dictating, to first order, dynamic response landscapes external forcings. We review explore stream‐power erosion model in an effort (1) elucidate its consequences terms large‐scale topographic (fluvial) sensitivity forcing, (2) derive relationship for system time...
The topographic evolution of orogens is fundamentally dictated by rates and patterns bedrock-channel incision. Quantitative field assessments process-based laws are needed to accurately describe landscape uplift denudation in response tectonics climate. We evaluate calibrate the shear stress (or similar unit stream-power) bedrock-incision model studying stream profiles a tectonically active mountain range. Previous work on emergent marine terraces Mendocino triple junction region northern...
Developing a quantitative understanding of the factors that control rate river incision into bedrock is critical to studies landscape evolution and linkages between climate, erosion, tectonics. Current models long‐term network differ significantly in their treatment role sediment flux. We analyze implications various sediment‐flux‐dependent for large‐scale topography, an attempt (1) identify quantifiable diagnostic differences could be detected from topographic data or transient responses...
Catchment morphology and drainage density are strongly influenced by hillslope processes. The consequences of several different process laws explored in a series experiments with numerical model basin evolution. Five models considered, including simple diffusive‐advective transition, runoff generation threshold, an erosion two types threshold‐activated landsliding. These processes alter both the visual appearance landscape predicted relationship between slope contributing area. On basis...
Recent investigations have shown that the extent of channel network in some drainage basins is controlled by a threshold for overland flow erosion. The sensitivity such to climate change analyzed using physically based model basin evolution. GOLEM simulates evolution under action weathering processes, hillslope transport, and fluvial bedrock erosion sediment transport. Results from perturbation analyses reveal nature timescale response depends on direction change. An increase runoff...
Abstract Geomorphology is currently in a period of resurgence as we seek to explain the diversity, origins and dynamics terrain on Earth other planets an era increased environmental awareness. Yet there great deal still do not know about physics chemistry processes that weaken rock transport mass across planet's surface. Discovering refining relevant geomorphic functions requires combination careful field measurements, lab experiments, use longer‐term natural experiments test current theory...
Erosional escarpments are common features of high‐elevation rifted continents. Fission track data suggest that these form by base level lowering and/or marginal uplift during rifting, followed lateral retreat an erosion front across tens to hundreds kilometers. Previous modeling studies have shown this characteristic pattern denudation can a profound impact upon isostatic and the evolution offshore sedimentary basins. Yet at present there is only rudimentary understanding geomorphic...
Mechanistic theories of fluvial erosion are essential for quantifying large‐scale orogenic denudation. We examine the topographic implications two leading classes river model, detachment‐limited and transport‐limited, in order to identify diagnostic testable differences between them. Several formulations predict distinctly different longitudinal profile shapes, which shown be closely linked terrain morphology. Of these, some can rejected on basis unrealistic morphology slope‐area scaling. An...
[1] Runoff during intense rainstorms plays a major role in generating debris flows many alpine areas and burned steeplands. Yet compared to flow initiation from shallow landslides, the mechanics by which runoff generates are less understood. To better understand surface water runoff, we monitored stage rainfall associated with headwaters of two small catchments: bedrock-dominated basin central Colorado (0.06 km2) recently area southern California (0.01 km2). We also obtained video footage...
ABSTRACT In this article we craft process‐specific algorithms that capture climate control of hillslope evolution in order to elucidate the legacy past on present critical zone architecture and topography. Models traditionally comprise rock detachment into mobile layer, regolith transport, a channel incision or aggradation boundary condition. We extend system deep by considering weathering damage below which strength is diminished; degree conditions rate production. first discuss generic...
Abstract. The ability to model surface processes and couple them both subsurface atmospheric regimes has proven invaluable research in the Earth planetary sciences. However, creating a new typically demands very large investment of time, modifying an existing address problem means work is constrained its detriment by adaptations for different problem. Landlab open-source software framework explicitly designed accelerate development process models providing (1) set tools grid structures –...
We develop a simple stochastic theory for erosion and sediment transport, based on the Poisson pulse rainfall model, in order to analyze how variability runoff influences drainage basin evolution. Two cases are considered: transport by rills channels particle detachment from bedrock or cohesive soils. Analytical numerical results show that under some circumstances, can have an impact equal greater than of mean amount. The predicted sensitivity is greatest when (1) thresholds generation...
Fluvial erosion of bedrock occurs during occasional flood events when boundary shear stress exceeds a critical threshold to initiate incision. Therefore efforts model the evolution topography over long timescales should include an and be driven by stochastic distribution erosive events. However, most incision models ignore as second‐order detail. In addition, climate is poorly represented in landscape models, so quantitative relationship between rate measurable climatic variables has been...
Abstract Long‐term average rates of channel erosion and sediment transport depend on the frequency–magnitude characteristics flood flows that exceed an threshold. Using a Poisson model for rainfall runoff, analytical solutions are developed stream incision in presence such Solutions derived numerically tested three erosion/transport formulas: Howard–Kerby shear‐stress model, Bridge–Dominic generic model. Results imply non‐linearity resulting from threshold effects can have first‐order impact...
Research Article| February 01, 2007 Bedrock channel adjustment to tectonic forcing: Implications for predicting river incision rates Alexander C. Whittaker; Whittaker 1Grant Institute of Earth Science, School GeoSciences, University Edinburgh, West Mains Road, Edinburgh EH9 3JW, Scotland, UK Search other works by this author on: GSW Google Scholar Patience A. Cowie; Cowie Mikaël Attal; Attal Gregory E. Tucker; Tucker 2Cooperative in Environmental Sciences (CIRES) and Department Geological...
The rate of sediment influx to a basin exerts first‐order control on stratal architecture. Despite its importance, however, little is known about how flux varies as function morphotectonic processes in the source terrain, such fold and thrust growth, variations bedrock lithology, drainage pattern changes temporary storage intermontane basins. In this study, these factors are explored with mathematical model topographic evolution which couples fluvial erosion kinematics. calibrated by...
Debris flows can dramatically increase their volume, and hence destructive potential, by entraining sediment. Yet quantitative constraints on rates mechanics of sediment entrainment debris are limited. Using an in situ sensor network the headwaters a natural catchment we measured flow bed properties during six erosive debris‐flow events. Despite similar thicknesses entrained across all events, time‐averaged were significantly faster for that was saturated prior to arrival compared with dry....
Channel geometry exerts a fundamental control on fluvial processes. Recent work has shown that bedrock channel width depends number of parameters, including slope, and is not solely function drainage area as commonly assumed. The present represents the first attempt to investigate consequences dynamic, gradient‐sensitive adjustment for drainage‐basin evolution. We use Channel‐Hillslope Integrated Landscape Development (CHILD) model analyze response catchment given tectonic perturbation,...
In many tectonically active regions on Earth, landslides dominate sediment delivery to channels. While cosmogenic radionuclides (CRN) represent a valuable tool document basin‐averaged erosion rates, better understanding of CRN dynamics in these systems is required before rates can be reliably inferred from concentrations. The stochastic nature results variability concentrations both alluvial and hillslope samples that difficult poorly understood. To guide sampling strategies, we developed...