My research focuses on landslide hydrology and thresholds for landslide warning systems. My background is in hillslope hydrology and numerical modeling of surface and near-surface hydrological processes, which I apply to improve quantitative characterization of landslide initiation potential. I manage several real-time landslide monitoring sites and the national landslide inventory database.
PROFESSIONAL EXPERIENCE
2015-present Research Geologist, Landslides Hazards Program, USGS, Golden, CO
2013-2014 Assistant Professor, Department of Geological Sciences, University of North Carolina, Chapel Hill, NC
2010-2013 Hydrologist, Unsaturated Zone Flow Project, USGS, Menlo Park, CA
2005-2009 Physical Scientist, Unsaturated Zone Flow Project, USGS, Menlo Park, CA
EDUCATION
2009 Ph.D. in Hydrogeology, Stanford University, Stanford, CA
2001 B.A. in Geology, Pomona College, Claremont, CA
Science and Products
Sitka, AK
Toro Negro, Puerto Rico
Utuado, Puerto Rico
Seattle Area, Washington
Portland, Oregon
Knife Ridge, Elliott State Forest, Oregon
Poplar Cove, Nantahala National Forest, North Carolina
Mooney Gap, Coweeta Experimental Forest, North Carolina
Bent Creek Experimental Forest, North Carolina
Landslides Can Cause More Landslides
Integrating Disparate Spatial Datasets from Local to National Scale for Open-Access Web-Based Visualization and Analysis: A Case Study Compiling U.S. Landslide Inventories
Landslide Inventories across the United States version 2
Hydrologic, slope movement, and soil property data from the coastal bluffs of the Atlantic Highlands, New Jersey, 2016-2018
Time-lapse photography of an active coastal-bluff landslide, Mukilteo, Washington, August 2015 - May 2016
Results of Hydrologic Monitoring on Landslide-prone Coastal Bluffs near Mukilteo, Washington
National strategy for landslide loss reduction
Constructing a large-scale landslide database across heterogeneous environments using task-specific model updates
Clays are not created equal: How clay mineral type affects soil parameterization
HydroMet: A new code for automated objective optimization of hydrometeorological thresholds for landslide initiation
Evaluation of techniques for mitigating snowmelt infiltration-induced landsliding in a highway embankment
Rapid-response unsaturated zone hydrology: Small-scale data, small-scale theory, big problems
Numerical analysis of the effect of subgrid variability in a physically based hydrological model on runoff, soil moisture, and slope stability
Incorporating the effects of complex soil layering and thickness local variability into distributed landslide susceptibility assessments
In-situ monitoring of infiltration-induced instability of I-70 embankment west of the Eisenhower-Johnson Memorial Tunnels, phase III
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 Rico posit that hillslope soils remain wet through
Deep Learning as a tool to forecast hydrologic response for landslide-prone hillslopes
Community for data integration 2018 funded project report
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
- Science
Sitka, AK
On August 18, 2015, heavy rainfall triggered around 60 landslides in and around the city of Sitka, AK. The landslides moved downslope rapidly; several were damaging and one of these demolished a home on South Kramer Avenue killing three people.Toro Negro, Puerto Rico
The USGS has installed instruments in a steep hillside northwest of the municipality of Villalba in the Toro Negro State Forest.Utuado, Puerto Rico
The USGS has installed instruments in a steep hillside east of the municipality of Utuado.Seattle Area, Washington
Monitoring at this site is for researching rainfall thresholds for forecasting landslide potential. Shallow landslides are common on coastal bluffs overlooking Puget Sound.Portland, Oregon
Landslides in the West Hills of Portland pose a hazard to people and property.Knife Ridge, Elliott State Forest, Oregon
The USGS and its cooperators have installed instruments in a steep hillside about 20 km southeast of Reedsport in the Elliott State Forest.Poplar Cove, Nantahala National Forest, North Carolina
The USGS and its cooperators have installed instruments in a steep hillside about 17.5 km southwest of Franklin, NC in the Nantahala National Forest.Mooney Gap, Coweeta Experimental Forest, North Carolina
The USGS and its cooperators have installed instruments in a steep hillside about 16 km southeast of Otto, NC in the Coweeta Experimental Forest.Bent Creek Experimental Forest, North Carolina
The USGS and its cooperators have installed instruments in a steep hillside about 38.5 km south of Asheville, NC in the Bent Creek Experimental Forest.Landslides Can Cause More Landslides
Release Date: MAY 15, 2018 The deadliest individual landslides in the U.S. recently were in places where there had previously been a landslide. Why do landslides happen in the same place instead of on nearby slopes that appear to be just as likely, if not more likely, to slide?Integrating Disparate Spatial Datasets from Local to National Scale for Open-Access Web-Based Visualization and Analysis: A Case Study Compiling U.S. Landslide Inventories
Spatial data on landslide occurrence across the U.S. varies greatly in quality, accessibility, and extent. This problem of data variability is common across USGS Mission Areas; it presents an obstacle to developing national-scale products and to identifying areas with relatively good/bad data coverage. We compiled available data of known landslides into a national-scale, searchable online map, whi - Data
Landslide Inventories across the United States version 2
Landslides are damaging and deadly, and they occur in every U.S. state. However, our current ability to understand landslide hazards at the national scale is limited, in part because spatial data on landslide occurrence across the U.S. varies greatly in quality, accessibility, and extent. Landslide inventories are typically collected and maintained by different agencies and institutions, usually wHydrologic, slope movement, and soil property data from the coastal bluffs of the Atlantic Highlands, New Jersey, 2016-2018
Seasonal variations in vegetation, rainfall, and soil moisture conditions have the potential to impact the slope stability of locally forested coastal bluffs in the Atlantic Highlands of New Jersey. Both the seasonality and rainfall amounts of the two types of storms that induce shallow landslides in the area vary considerably. Most of the documented historical landslides are the result of heavy rTime-lapse photography of an active coastal-bluff landslide, Mukilteo, Washington, August 2015 - May 2016
A time-lapse camera was used to document periodic reactivation of a complex landslide on a steep coastal bluff in Mukilteo, Washington. This landslide is one of four monitoring sites initiated by the U.S Geological Survey to investigate hill-slope hydrology and landslide hazards affecting the railway corridor along the eastern shore of Puget Sound between the cities of Seattle and Everett (Mirus eResults of Hydrologic Monitoring on Landslide-prone Coastal Bluffs near Mukilteo, Washington
A hydrologic monitoring network was installed to investigate landslide hazards affecting the railway corridor along the eastern shore of Puget Sound between Seattle and Everett, near Mukilteo, Washington. During the summer of 2015, the U.S. Geological Survey installed instrumentation at four sites to measure rainfall and air temperature every 15 minutes. Two of the four sites are installed on cont - Publications
Filter Total Items: 41
National strategy for landslide loss reduction
Executive SummaryLandslide hazards are present in all 50 States and most U.S. territories, and they affect lives, property, infrastructure, and the environment. Landslides are the downslope movement of earth materials under the force of gravity. They can occur without any obvious trigger. Widespread or severe landslide events are often driven by such hazards as hurricanes, earthquakes, volcanicConstructing a large-scale landslide database across heterogeneous environments using task-specific model updates
Preparation and mitigation efforts for widespread landslide hazards can be aided by a large-scale, well-labeled landslide inventory with high location accuracy. Recent smallscale studies for pixel-wise labeling of potential landslide areas in remotely-sensed images using deep learning (DL) showed potential but were based on data from very small, homogeneous regions with unproven model transferabilClays are not created equal: How clay mineral type affects soil parameterization
Clay minerals dominate the soil colloidal fraction and its specific surface area. Differences among clay mineral types significantly influence their effects on soil hydrological and mechanical behavior. Presently, the soil clay content is used to parameterize soil hydraulic and mechanical properties (SHMP) for land surface models while disregarding the type of clay mineral. This undifferentiated uHydroMet: A new code for automated objective optimization of hydrometeorological thresholds for landslide initiation
Landslide detection and warning systems are important tools for mitigation of potential hazards in landslide prone areas. Traditionally, warning systems for shallow landslides have been informed by rainfall intensity-duration thresholds. More recent advances have introduced the concept of hydrometeorological thresholds that are informed not only by rainfall, but also by subsurface hydrological meaEvaluation of techniques for mitigating snowmelt infiltration-induced landsliding in a highway embankment
Infiltration-induced landslides threaten transportation infrastructure around the world, and impose both direct costs through repair and remediation work and indirect costs through lost economic activity. Therefore, finding the most cost-effective techniques to mitigate slope failures that can impact critical infrastructure links is desirable. The Straight Creek landslide, which affects a segmentRapid-response unsaturated zone hydrology: Small-scale data, small-scale theory, big problems
The unsaturated zone (UZ) extends across the Earth’s terrestrial surface and is central to many problems related to land and water resource management. Flow of water through the UZ is typically thought to be slow and diffusive, such that it could attenuate fluxes and dampen variability between atmospheric inputs and underlying aquifer systems. This would reduce water resource vulnerability to contNumerical 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 headwater catchments within the cell size typicallIncorporating 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 average textural classifications; the potential impact oIn-situ monitoring of infiltration-induced instability of I-70 embankment west of the Eisenhower-Johnson Memorial Tunnels, phase III
A new methodology that uses recent advances in unsaturated soil mechanics and hydrology was developed and tested. The approach consists of using soil suction and moisture content field information in the prediction of the likelihood of landslide movement. The testing ground was an active landslide on I-70 west of the Eisenhower/Johnson Memorial Tunnels. A joint effort between Colorado School of MiHillslopes 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 Rico posit that hillslope soils remain wet through
Deep Learning as a tool to forecast hydrologic response for landslide-prone hillslopes
Empirical thresholds for landslide warning systems have benefitted from the incorporation of soil‐hydrologic monitoring data, but the mechanistic basis for their predictive capabilities is limited. Although physically based hydrologic models can accurately simulate changes in soil moisture and pore pressure that promote landslides, their utility is restricted by high computational costs and nonuniCommunity for data integration 2018 funded project report
The U.S. Geological Survey Community for Data Integration annually funds small projects focusing on data integration for interdisciplinary research, innovative data management, and demonstration of new technologies. This report provides a summary of the 10 projects funded in fiscal year 2018, outlining their goals, activities, and accomplishments.Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.