Rex Baum
Rex worked as a research geologist in the Landslide Hazards Program of the U.S. Geological Survey.
While at the USGS Rex conducted research on landslide processes, monitoring, forecasting and warning, and hazards in the Colorado Plateau, Colorado Front Range, southern Rocky Mountains, southwest Ohio, central California, Hawaii, the Pacific Northwest, Puerto Rico, Poland, and El Salvador, Central America.
Education and Certifications
Ph.D., Geology, University of Cincinnati
M.S., Geology, University of Cincinnati
B.U.S., University of New Mexico
Science and Products
Filter Total Items: 13
Map data and Unmanned Aircraft System imagery from the May 25, 2014 West Salt Creek rock avalanche in western Colorado
On May 25, 2014, a rain-on-snow induced rock avalanche occurred in the West Salt Creek Valley on the northern flank of Grand Mesa in western Colorado. The avalanche traveled 4.6 km down the confined valley, killing 3 people. The avalanche was rare for the contiguous U.S. because of its large size (54.5 Mm3) and long travel distance. To understand the avalanche failure sequence, mechanisms, and mob
Filter Total Items: 70
Integrating real-time subsurface hydrologic monitoring with empirical rainfall thresholds to improve landslide early warning
Early warning for rainfall-induced shallow landsliding can help reduce fatalities and economic losses. Although these commonly occurring landslides are typically triggered by subsurface hydrological processes, most early warning criteria rely exclusively on empirical rainfall thresholds and other indirect proxies for subsurface wetness. We explore the utility of explicitly accounting for anteceden
Authors
Benjamin B. Mirus, Rachel E. Becker, Rex L. Baum, Joel B. Smith
THRESH—Software for tracking rainfall thresholds for landslide and debris-flow occurrence, user manual
Precipitation thresholds are used in many areas to provide early warning of precipitation-induced landslides and debris flows, and the software distribution THRESH is designed for automated tracking of precipitation, including precipitation forecasts, relative to thresholds for landslide occurrence. This software is also useful for analyzing multiyear precipitation records to compare timing of thr
Authors
Rex L. Baum, Sarah J. Fischer, Jacob C. Vigil
Results of hydrologic monitoring of a landslide-prone hillslope in Portland’s West Hills, Oregon, 2006–2017
The West Hills of Portland, in the southern Tualatin Mountains, trend northwest along the west side of Portland, Oregon. These silt-mantled mountains receive significant wet-season precipitation and are prone to sliding during wet conditions, occasionally resulting in property damage or casualties. In an effort to develop a baseline for interpretive analysis of the groundwater response to rainfall
Authors
Joel B. Smith, Jonathan W. Godt, Rex L. Baum, Jeffrey A. Coe, William L. Ellis, Eric S. Jones, Scott F. Burns
Hydrologic impacts of landslide disturbances: Implications for remobilization and hazard persistence
Landslides typically alter hillslope topography, but may also change the hydrologic connectivity and subsurface water-storage dynamics. In settings where mobile materials are not completely evacuated from steep slopes, influences of landslide disturbances on hillslope hydrology and susceptibility to subsequent failures remain poorly characterized. Since landslides often recur at the site of previo
Authors
Benjamin B. Mirus, Joel B. Smith, Rex L. Baum
Results 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 monitoring equipment at four sites equipped with instrumentation to measure rainfall and air temperature every 15 minutes. Two of t
Authors
Joel B. Smith, Rex L. Baum, Benjamin B. Mirus, Abigail R. Michel, Ben Stark
Precipitation thresholds for landslide occurrence near Seattle, Mukilteo, and Everett, Washington
Shallow landslides along coastal bluffs frequently occur in the railway corridor between Seattle and Everett, Washington. These slides disrupt passenger rail service, both because of required track maintenance and because the railroad owner, Burlington Northern Santa Fe Railway, does not allow passenger travel for 48 hours after a disruptive landslide. Sound Transit, which operates commuter trains
Authors
Caroline R. Scheevel, Rex L. Baum, Benjamin B. Mirus, Joel B. Smith
Effects of topographic data quality on estimates of shallow slope stability using different regolith depth models
Thickness of colluvium or regolith overlying bedrock or other consolidated materials is a major factor in determining stability of unconsolidated earth materials on steep slopes. Many efforts to model spatially distributed slope stability, for example to assess susceptibility to shallow landslides, have relied on estimates of constant thickness, constant depth, or simple models of thickness (or de
Authors
Rex L. Baum
Elucidating the role of vegetation in the initiation of rainfall-induced shallow landslides: Insights from an extreme rainfall event in the Colorado Front Range
More than 1100 debris flows were mobilized from shallow landslides during a rainstorm from 9 to 13 September 2013 in the Colorado Front Range, with the vast majority initiating on sparsely vegetated, south facing terrain. To investigate the physical processes responsible for the observed aspect control, we made measurements of soil properties on a densely forested north facing hillslope and a gras
Authors
Luke McGuire, Francis K. Rengers, Jason W. Kean, Jeffrey A. Coe, Benjamin B. Mirus, Rex L. Baum, Jonathan W. Godt
The influence of vegetation cover on debris-flow density during an extreme rainfall in the northern Colorado Front Range
We explored regional influences on debris-flow initiation throughout the Colorado Front Range (Colorado, USA) by exploiting a unique data set of more than 1100 debris flows that initiated during a 5 day rainstorm in 2013. Using geospatial data, we examined the influence of rain, hillslope angle, hillslope aspect, and vegetation density on debris-flow initiation. In particular we used a greenness i
Authors
Francis K. Rengers, Luke McGuire, Jeffrey A. Coe, Jason W. Kean, Rex L. Baum, Dennis M. Staley, Jonathan W. Godt
Assessing landslide potential on coastal bluffs near Mukilteo, Washington—Geologic site characterization for hydrologic monitoring
During the summer 2015, the U.S. Geological Survey collected geologic and geotechnical data for two sites on coastal bluffs along the eastern shore of Puget Sound, Washington. The U.S. Geological Survey also installed hydrologic instrumentation at the sites and collected specimens for laboratory testing. The two sites are located on City of Mukilteo open-space land and are about 0.6 kilometers apa
Authors
Benjamin B. Mirus, Joel B. Smith, Benjamin Stark, York Lewis, Abigail Michel, Rex L. Baum
Rock-avalanche dynamics revealed by large-scale field mapping and seismic signals at a highly mobile avalanche in the West Salt Creek valley, western Colorado
On 25 May 2014, a rain-on-snow–induced rock avalanche occurred in the West Salt Creek valley on the northern flank of Grand Mesa in western Colorado (United States). The avalanche mobilized from a preexisting rock slide in the Green River Formation and traveled 4.6 km down the confined valley, killing three people. The avalanche was rare for the contiguous United States because of its large size (
Authors
Jeffrey A. Coe, Rex L. Baum, Kate E. Allstadt, Bernard Kochevar, Robert G. Schmitt, Matthew L. Morgan, Jonathan L. White, Benjamin T. Stratton, Timothy A. Hayashi, Jason W. Kean
New insights into debris-flow hazards from an extraordinary event in the Colorado Front Range
Rainfall on 9–13 September 2013 triggered at least 1,138 debris flows in a 3430 km2 area of the Colorado Front Range. The historical record reveals that the occurrence of these flows over such a large area in the interior of North America is highly unusual. Rainfall that triggered the debris flows began after ~75 mm of antecedent rain had fallen, a relatively low amount compared to other parts of
Authors
Jeffrey A. Coe, Jason W. Kean, Jonathan W. Godt, Rex L. Baum, Eric S. Jones, David Gochis, Gregory S Anderson
Science and Products
Filter Total Items: 13
Map data and Unmanned Aircraft System imagery from the May 25, 2014 West Salt Creek rock avalanche in western Colorado
On May 25, 2014, a rain-on-snow induced rock avalanche occurred in the West Salt Creek Valley on the northern flank of Grand Mesa in western Colorado. The avalanche traveled 4.6 km down the confined valley, killing 3 people. The avalanche was rare for the contiguous U.S. because of its large size (54.5 Mm3) and long travel distance. To understand the avalanche failure sequence, mechanisms, and mob
Filter Total Items: 70
Integrating real-time subsurface hydrologic monitoring with empirical rainfall thresholds to improve landslide early warning
Early warning for rainfall-induced shallow landsliding can help reduce fatalities and economic losses. Although these commonly occurring landslides are typically triggered by subsurface hydrological processes, most early warning criteria rely exclusively on empirical rainfall thresholds and other indirect proxies for subsurface wetness. We explore the utility of explicitly accounting for anteceden
Authors
Benjamin B. Mirus, Rachel E. Becker, Rex L. Baum, Joel B. Smith
THRESH—Software for tracking rainfall thresholds for landslide and debris-flow occurrence, user manual
Precipitation thresholds are used in many areas to provide early warning of precipitation-induced landslides and debris flows, and the software distribution THRESH is designed for automated tracking of precipitation, including precipitation forecasts, relative to thresholds for landslide occurrence. This software is also useful for analyzing multiyear precipitation records to compare timing of thr
Authors
Rex L. Baum, Sarah J. Fischer, Jacob C. Vigil
Results of hydrologic monitoring of a landslide-prone hillslope in Portland’s West Hills, Oregon, 2006–2017
The West Hills of Portland, in the southern Tualatin Mountains, trend northwest along the west side of Portland, Oregon. These silt-mantled mountains receive significant wet-season precipitation and are prone to sliding during wet conditions, occasionally resulting in property damage or casualties. In an effort to develop a baseline for interpretive analysis of the groundwater response to rainfall
Authors
Joel B. Smith, Jonathan W. Godt, Rex L. Baum, Jeffrey A. Coe, William L. Ellis, Eric S. Jones, Scott F. Burns
Hydrologic impacts of landslide disturbances: Implications for remobilization and hazard persistence
Landslides typically alter hillslope topography, but may also change the hydrologic connectivity and subsurface water-storage dynamics. In settings where mobile materials are not completely evacuated from steep slopes, influences of landslide disturbances on hillslope hydrology and susceptibility to subsequent failures remain poorly characterized. Since landslides often recur at the site of previo
Authors
Benjamin B. Mirus, Joel B. Smith, Rex L. Baum
Results 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 monitoring equipment at four sites equipped with instrumentation to measure rainfall and air temperature every 15 minutes. Two of t
Authors
Joel B. Smith, Rex L. Baum, Benjamin B. Mirus, Abigail R. Michel, Ben Stark
Precipitation thresholds for landslide occurrence near Seattle, Mukilteo, and Everett, Washington
Shallow landslides along coastal bluffs frequently occur in the railway corridor between Seattle and Everett, Washington. These slides disrupt passenger rail service, both because of required track maintenance and because the railroad owner, Burlington Northern Santa Fe Railway, does not allow passenger travel for 48 hours after a disruptive landslide. Sound Transit, which operates commuter trains
Authors
Caroline R. Scheevel, Rex L. Baum, Benjamin B. Mirus, Joel B. Smith
Effects of topographic data quality on estimates of shallow slope stability using different regolith depth models
Thickness of colluvium or regolith overlying bedrock or other consolidated materials is a major factor in determining stability of unconsolidated earth materials on steep slopes. Many efforts to model spatially distributed slope stability, for example to assess susceptibility to shallow landslides, have relied on estimates of constant thickness, constant depth, or simple models of thickness (or de
Authors
Rex L. Baum
Elucidating the role of vegetation in the initiation of rainfall-induced shallow landslides: Insights from an extreme rainfall event in the Colorado Front Range
More than 1100 debris flows were mobilized from shallow landslides during a rainstorm from 9 to 13 September 2013 in the Colorado Front Range, with the vast majority initiating on sparsely vegetated, south facing terrain. To investigate the physical processes responsible for the observed aspect control, we made measurements of soil properties on a densely forested north facing hillslope and a gras
Authors
Luke McGuire, Francis K. Rengers, Jason W. Kean, Jeffrey A. Coe, Benjamin B. Mirus, Rex L. Baum, Jonathan W. Godt
The influence of vegetation cover on debris-flow density during an extreme rainfall in the northern Colorado Front Range
We explored regional influences on debris-flow initiation throughout the Colorado Front Range (Colorado, USA) by exploiting a unique data set of more than 1100 debris flows that initiated during a 5 day rainstorm in 2013. Using geospatial data, we examined the influence of rain, hillslope angle, hillslope aspect, and vegetation density on debris-flow initiation. In particular we used a greenness i
Authors
Francis K. Rengers, Luke McGuire, Jeffrey A. Coe, Jason W. Kean, Rex L. Baum, Dennis M. Staley, Jonathan W. Godt
Assessing landslide potential on coastal bluffs near Mukilteo, Washington—Geologic site characterization for hydrologic monitoring
During the summer 2015, the U.S. Geological Survey collected geologic and geotechnical data for two sites on coastal bluffs along the eastern shore of Puget Sound, Washington. The U.S. Geological Survey also installed hydrologic instrumentation at the sites and collected specimens for laboratory testing. The two sites are located on City of Mukilteo open-space land and are about 0.6 kilometers apa
Authors
Benjamin B. Mirus, Joel B. Smith, Benjamin Stark, York Lewis, Abigail Michel, Rex L. Baum
Rock-avalanche dynamics revealed by large-scale field mapping and seismic signals at a highly mobile avalanche in the West Salt Creek valley, western Colorado
On 25 May 2014, a rain-on-snow–induced rock avalanche occurred in the West Salt Creek valley on the northern flank of Grand Mesa in western Colorado (United States). The avalanche mobilized from a preexisting rock slide in the Green River Formation and traveled 4.6 km down the confined valley, killing three people. The avalanche was rare for the contiguous United States because of its large size (
Authors
Jeffrey A. Coe, Rex L. Baum, Kate E. Allstadt, Bernard Kochevar, Robert G. Schmitt, Matthew L. Morgan, Jonathan L. White, Benjamin T. Stratton, Timothy A. Hayashi, Jason W. Kean
New insights into debris-flow hazards from an extraordinary event in the Colorado Front Range
Rainfall on 9–13 September 2013 triggered at least 1,138 debris flows in a 3430 km2 area of the Colorado Front Range. The historical record reveals that the occurrence of these flows over such a large area in the interior of North America is highly unusual. Rainfall that triggered the debris flows began after ~75 mm of antecedent rain had fallen, a relatively low amount compared to other parts of
Authors
Jeffrey A. Coe, Jason W. Kean, Jonathan W. Godt, Rex L. Baum, Eric S. Jones, David Gochis, Gregory S Anderson