Landslide Hazards Program
Publications
Numerical analysis of the effect of subgrid variability in a physically based hydrological model on runoff, soil moisture, and slope stability
In coarse resolution hydrological modeling we face the problem of subgrid variability, the effects of which are difficult to express and are often hidden in the parameterization and calibration. We present a numerical experiment with the physically based hydrological model ParFlow‐CLM with which we quantify the effect of subgrid heterogeneities in...
Leonarduzzi, E.; Maxwell, R. M.; Mirus, Benjamin B.; Molnar, P. Incorporating the effects of complex soil layering and thickness local variability into distributed landslide susceptibility assessments
Incorporating the influence of soil layering and local variability into the parameterizations of physics-based numerical models for distributed landslide susceptibility assessments remains a challenge. Typical applications employ substantial simplifications including homogeneous soil units and soil-hydraulic properties assigned based only on...
Fusco, F.; Mirus, Benjamin B.; Baum, Rex L.; Calcaterra, D.; De Vita, P. Forecasting the frequency and magnitude of postfire debris flows across southern California
Southern California has a long history of damaging debris flows after wildfire. Despite recurrent loss, forecasts of the frequency and magnitude of postfire debris flows are not available for the region like they are for earthquakes. Instead, debris flow hazards are typically assessed in a reactive manner after wildfires. Such assessments are...
Kean, Jason W.; Staley, Dennis M. Modeling hydrologic processes associated with soil saturation and debris flow initiation during the September 2013 storm, Colorado Front Range
Seven days of extreme rainfall during September 2013 produced more than 1100 debris flows in the Colorado Front Range, about 78% of which occurred on south-facing slopes (SFS). Previously published soil moisture (volumetric water content) observations suggest that SFS were wetter than north-facing slopes (NFS) during the event, which contrasts...
Timilsina, Sujana; Niemann, Jeffrey D.; Rathburn, Sara L.; Rengers, Francis K.; Nelson, Peter A. Rapid sensitivity analysis for reducing uncertainty in landslide hazard assessments
One of the challenges in assessing temporal and spatial aspects of landslide hazard using process-based models is estimating model input parameters, especially in areas where limited measurements of soil and rock properties are available. In an effort to simplify and streamline parameter estimation, development of a simple, rapid approach to...
Baum, Rex L. Wildfire and landscape change
Wildfire is a worldwide phenomenon that is expected to increase in extent and severity in the future, due to fuel accumulations, shifting land management practices, and climate change. It immediately affects the landscape by removing vegetation, depositing ash, influencing water-repellent soil formation, and physically weathering boulders and...
Santi, Paul M.; Rengers, Francis K. Detection and assessment of a large and potentially‐tsunamigenic periglacial landslide in Barry Arm, Alaska
The retreat of glaciers in response to global warming has the potential to trigger landslides in glaciated regions around the globe. Landslides that enter fjords or lakes can cause tsunamis, which endanger people and infrastructure far from the landslide itself. Here we document the ongoing movement of an unstable slope (total volume of 455...
Dai, Chunli; Higman, Bretwood; Lynett, Patrick J.; Jacquemart, Mylène; Howat, Ian; Liljedahl, Anna K.; Dufresne, Anja; Freymueller, Jeffery T.; Geertsema, Marten; Jones, Melissa Ward; Haeussler, Peter Twelve-year dynamics and rainfall thresholds for alternating creep and rapid movement of the Hooskanaden landslide from integrating InSAR, pixel offset tracking, and borehole and hydrological measurements
The Hooskanaden landslide is a large (~600 m wide × 1,300 m long), deep (~30 – 45 m) slide located in southwestern Oregon. Since 1958, it has had five moderate/major movements that catastrophically damaged the intersecting U.S. Highway 101, along with persistent slow wet‐season movements and a long‐term accelerating trend...
Xu, Y.; Lu, Z.; Schulz, William; Kim, J. Measuring basal force fluctuations of debris flows using seismic recordings and empirical green's functions
We present a novel method for measuring the fluctuating basal normal and shear stresses of debris flows by using along‐channel seismic recordings. Our method couples a simple parameterization of a debris flow as a seismic source with direct measurements of seismic path effects using empirical Green's functions generated with a force hammer. We...
Allstadt, Kate; Farin, Maxime; Iverson, Richard M.; Obryk, Maciej; Kean, Jason W.; Tsai, Victor C.; Rapstine, Thomas D; Logan, Matthew Hillslopes in humid-tropical climates aren’t always wet: Implications for hydrologic response and landslide initiation in Puerto Rico, USA
The devastating impacts of the widespread flooding and landsliding in Puerto Rico following the September 2017 landfall of Hurricane Maria highlight the increasingly extreme atmospheric disturbances and enhanced hazard potential in mountainous humid‐tropical climate zones. Long‐standing conceptual models for hydrologically driven hazards in Puerto...
Thomas, Matthew A.; Mirus, Benjamin B.; Smith, Joel B. Landslides after wildfire: Initiation, magnitude, and mobility
In the semiarid Southwestern USA, wildfires are commonly followed by runoff-generated debris flows because wildfires remove vegetation and ground cover, which reduces soil infiltration capacity and increases soil erodibility. At a study site in Southern California, we initially observed runoff-generated debris flows in the first year following...
Rengers, Francis K.; McGuire, Luke; Oakley, Nina S.; Kean, Jason W.; Staley, Dennis M.; Tang, Hui Reconstructing the velocity and deformation of a rapid landslide using multiview video
Noncontact measurements of spatially varied ground surface deformation during landslide motion can provide important constraints on landslide mechanics. Here, we present and test a new method for extracting measurements of rapid landslide surface displacement and velocity (accelerations of approximately 1 m/s2) using sequences of stereo...
Rapstine, Thomas D; Rengers, Francis K.; Allstadt, Kate; Iverson, Richard M.; Smith, Joel B.; Obryk, Maciej; Logan, M.; Olsen, M. J.