Natural Hazards

Publications

Filter Total Items: 5,625
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Year Published: 2019

Event detection performance of the PLUM earthquake early warning algorithm in southern California

We test the Japanese ground‐motion‐based earthquake early warning (EEW) algorithm, propagation of local undamped motion (PLUM), in southern California with application to the U.S. ShakeAlert system. In late 2018, ShakeAlert began limited public alerting in Los Angeles to areas of expected modified Mercalli intensity (⁠IMMI⁠) 4.0+ for magnitude 5.0...

Cochran, Elizabeth S.; Bunn, Julian; Minson, Sarah E.; Baltay, Annemarie S.; Kilb, Deborah L.; Kodera, Y.; Hoshiba, Mitsuyuki

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Year Published: 2019

Source-dependent amplification of earthquake ground motions in deep sedimentary basins

Deep sedimentary basins amplify long-period shaking from seismic waves, increasing the seismic hazard for cities within such basins. We perform 3-D simulations of point source earthquakes distributed around the Seattle and Tacoma basins in Washington State, to examine the dependence of basin amplification on source azimuth, depth, and earthquake...

Moriarty, Erin; Vidale, John E.; Frankel, Arthur; Pratt, Thomas L.

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Year Published: 2019

A 4000-year history of debris flows in north-central Washington State, U.S.A.: Preliminary results from trenching and surficial geologic mapping at the Pope Creek fan

Long-term records of the magnitude and frequency of debris flows on fans are rare, but such records provide critical information needed for debris-flow hazard and risk assessments. This study explores the history of debris flows on a fan with seasonally inhabited cabins at Pope Creek along the Entiat River about 48 km upstream from the town of...

Coe, Jeffrey A.; Bessette-Kirton, Erin; Slaughter, Stephen; Rengers, Francis K.; Contreras, Trevor A.; Michelson, Katherin A; Taylor, Emily; Kean, Jason W.; Jacobacci, Kara; Hanson, Molly A
Coe, J.A., Bessette-Kirton, E.K., Slaughter, S.L., Rengers, F.K., Contreras, T.A., Mickelson, K.A., Taylor, E.M., Kean, J.W., Jacobacci, K.E., Hanson, M.A., 2019, A 4000-year history of debris flows in north-central Washington State, U.S.A.: preliminary results from trenching and surficial geologic mapping at the Pope Creek fan, in Kean, J.W., Coe, J.A., Santi, P.M., and Guillen, B.K., eds., Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment, Proceedings of the 7th International Conference on Debris Flow Hazards Mitigation, Golden, Colorado, p. 613-620.

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Year Published: 2019

Exploring controls on debris-flow surge velocity and peak discharge at Chalk Cliffs, Colorado, USA

We present a series of debris-flow events and use combined sensor and video data to explore how sediment concentration and triggering rainfall intensity affect the velocity and discharge of debris-flow surges generated by surface-water runoff. We analyze an initial data set of 49 surges from four debris-flow events recorded by a monitoring system...

Smith, Joel B.; Kean, Jason W.; Coe, Jeffrey A.
Smith, J.B., Kean, J.W., and Coe, J.A., 2019, Exploring controls on debris-flow surge velocity and peak discharge at Chalk Cliffs, Colorado, USA, in Kean, J.W., Coe, J.A., Santi, P.M., and Guillen, B.K., eds., Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment, Proceedings of the 7th International Conference on Debris Flow Hazards Mitigation, Golden, Colorado, p. 199-206.

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Year Published: 2019

An evaluation of debris-flow runout model accuracy and complexity in Montecito, CA: Towards a framework for regional inundation-hazard forecasting

Numerous debris-flow inundation models have been applied retroactively to noteworthy events around the world. While such studies can be useful in identifying controlling factors, calibrating model parameters, and assessing future hazards in specific study areas, model parameters tailored to individual events can be difficult to apply regionally....

Bessette-Kirton, Erin; Kean, Jason W.; Coe, Jeffrey A.; Rengers, Francis K.; Staley, Dennis M.
Bessette-Kirton, E.K., Kean, J.W., Coe, J.A., Rengers, F.K., Staley, D.M., 2019, An evaluation of debris-flow runout model accuracy and complexity in Montecito, California: Towards a framework for regional inundation-hazard forecasting, in Kean, J.W., Coe, J.A., Santi, P.M., and Guillen, B.K., eds., Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment, Proceedings of the 7th International Conference on Debris Flow Hazards Mitigation, Golden, Colorado p. 257-264.

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Year Published: 2019

Thin-layer sediment addition to an existing salt marsh to combat sea-level rise and improve endangered species habitat in California, USA

Current tidal marsh elevations and their accretion rates are important predictors of vulnerability to sea-level rise. When tidal marshes are at risk, adaptation measures, such as sediment addition to increase elevations, can be implemented to prevent degradation and loss. In 2016, wildlife managers prescribed a thin-layer sediment addition of...

Thorne, Karen M.; Freeman, Chase; Rosencranz, Jordan A.; Ganju, Neil Kamal; Guntenspergen, Glenn R.

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Year Published: 2019

Real-time monitoring of debris-flow velocity and mass deformation from field experiments with high sample rate lidar and video

Debris flows evolve in both time and space in complex ways, commonly starting as coherent failures but then quickly developing structures such as roll waves and surges. This process is readily observed, but difficult to study or quantify because of the speed at which it occurs. Many methods for studying debris flows consist of point measurements (...

Rengers, Francis K.; Rapstine, Thomas; Allstadt, Kate E.; Olsen, Michael; Bunn, Michael; Iverson, Richard M.; Kean, Jason W.; Leshchinsky, Ben; Logan, Matthew; Sharifi-Mood, Mahyar; Obryk, Maciej; Smith, Joel B.

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Year Published: 2019

Looking through the window of disturbance at post-wildfire debris-flow hazards

The extreme heat from wildfire alters soil properties and incinerates vegetation, leading to changes in infiltration capacity, ground cover, soil erodibility, and rainfall interception. These changes promote increases in runoff and sediment transport that increase the likelihood of runoff-generated debris flows. Over a period of several years,...

McGuire, Luke; Rengers, Francis K.; Kean, Jason W.; Staley, Dennis M.; Tang, Hui; Youberg, Ann

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Year Published: 2019

Topographic change detection at Chalk Cliffs, Colorado, USA, using Airborne LiDAR and UAS-based Structure-from-Motion photogrammetry

The Chalk Cliffs debris-flow site is a small headwater catchment incised into highly fractured and hydrothermally altered quartz monzonite in a semi-arid climate. Over half of the extremely steep basin is exposed bedrock. Debris flows occur multiple times per year in response to rainstorm events, typically during the summer monsoon season. The...

Barnhart, Katherine R; Rengers, Francis K.; Ghent Jessica N; Tucker, Gregory E.; Coe, Jeffrey A.; Kean, Jason W.; Smith, Joel B.; Staley, Dennis M.; Kleiber, William; Wiens, Ashton M

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Year Published: 2019

Data Report: Permeability, porosity, and frictional strength of core samples from IODP Expedition 366 in the Mariana forearc

Core samples from the International Ocean Discovery Program (IODP) Expedition 366 were tested in the laboratory to determine permeability, porosity, density, and frictional strength and their relation to mineralogy as part of an effort to understand hydro-mechanical processes at convergent plate margins. Seven samples were tested from a depth...

Morrow, Carolyn A.; Moore, Diane E.; Lockner, David A.; Bekins, Barbara A.
 Morrow, C.A., Moore, D.E., Lockner, D.A., and Bekins, B.A., 2019. Data report: permeability, porosity, and frictional strength of core samples from IODP Expedition 366 in the Mariana forearc. In Fryer, P., Wheat, C.G., Williams, T., and the Expedition 366 Scientists, Mariana Convergent Margin and South Chamorro Seamount. Proceedings of the International Ocean Discovery Program, 366: College Station, TX (International Ocean Discovery Program). https://doi.org/10.14379/iodp.proc.366.202.2019

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Year Published: 2019

Changes in hydrodynamics and wave energy as a result of seagrass decline along the shoreline of a microtidal back-barrier estuary

Seagrasses are marine flowering plants that provide key ecological services. In recent decades, multiple stressors have caused a worldwide decline in seagrass beds. Changes in bottom friction associated with seagrass loss are expected to influence the ability of estuarine systems to trap sediment inputs through local and regional changes in...

Donatelli, Carmine; Ganju, Neil Kamal; Kalra, Tarandeep S.; Fagherazzi, S; Leonardi, Nicoletta

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Year Published: 2019

The roles of flow acceleration and deceleration in sediment suspension in the surf zone

Prediction of sediment suspension in the surf zone remains elusive. We explore how suspended sediment concentration at 19 cm above the bed in the mid-surf zone during a storm is influenced by flow acceleration and deceleration. There is a tendency for higher suspended sediment concentrations during onshore flow, with decelerating onshore flows...

Jaffe, Bruce E.; La Selle, Seanpaul
Jaffe, B.E., and La Selle, S., 2019, The roles of flow acceleration and deceleration in sediment suspension in the surf zone: in Wang, P., Rosati, J.D., and Vallee, M., eds., Coastal Sediments 2019, Proceedings of the 9th International Conference: World Scientific, Hackensack, New Jersey, p. 565-576, https://doi.org/10.1142/9789811204487_0050.