Articles | Volume 26, issue 3
https://doi.org/10.5194/nhess-26-1435-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-26-1435-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
20 Mar 2026
Research article |
| 20 Mar 2026
| 20 Mar 2026
Characterizing geologic and climatic controls on rockfall hazards using an inventory and integrated kinematic and runout model: Skagway, Alaska, USA
Ian D. Wachino
Department of Earth Sciences, University of Oregon, Eugene, OR, 97403, USA
Department of Earth Sciences, University of Oregon, Eugene, OR, 97403, USA
Reuben Cash
Environmental Department, Skagway Traditional Council, Skagway, AK, 99840, USA
Annette I. Patton
Sitka Sound Science Center, Sitka, AK, 99835, USA
College of Forestry, Oregon State University, Corvallis, OR, 97331, USA
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Joshua J. Roering, Margaret M. Darrow, Annette I. Patton, and Aaron Jacobs
Nat. Hazards Earth Syst. Sci., 26, 587–610, https://doi.org/10.5194/nhess-26-587-2026, https://doi.org/10.5194/nhess-26-587-2026, 2026
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A deadly landslide struck Wrangell Island, Alaska, in November 2023, traveling over a kilometer and claiming six lives. Our study shows it was likely triggered by moderate rainfall combined with rapid snowmelt and drainage from a ridgetop wetland, which saturated deep soil deposits on a steep hillslope. The landslide grew unusually large as it entrained abundant soil. Findings highlight the role of storm patterns, geology, and hydrology in driving future landslide hazards in SE Alaska.
Nathaniel Klema, Leif Karlstrom, and Joshua Roering
EGUsphere, https://doi.org/10.5194/egusphere-2025-4431, https://doi.org/10.5194/egusphere-2025-4431, 2025
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Geomorphology is built on process models that take topographic geometry as inputs. However, many studies calculate these metrics on 2-d projections of topography rather than on true surfaces in 3-d space. In this work we apply classical surface theory to fluvial topography of the Oregon Coast Range, USA. This formal approach improves the accuracy of geometry calculations, extracts more information than standard methods, and sheds light on the organizational structure of landscapes.
Greg Balco, Alan J. Hidy, William T. Struble, and Joshua J. Roering
Geochronology, 6, 71–76, https://doi.org/10.5194/gchron-6-71-2024, https://doi.org/10.5194/gchron-6-71-2024, 2024
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We describe a new method of reconstructing the long-term, pre-observational frequency and/or intensity of wildfires in forested landscapes using trace concentrations of the noble gases helium and neon that are formed in soil mineral grains by cosmic-ray bombardment of the Earth's surface.
Annette I. Patton, Lisa V. Luna, Joshua J. Roering, Aaron Jacobs, Oliver Korup, and Benjamin B. Mirus
Nat. Hazards Earth Syst. Sci., 23, 3261–3284, https://doi.org/10.5194/nhess-23-3261-2023, https://doi.org/10.5194/nhess-23-3261-2023, 2023
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Landslide warning systems often use statistical models to predict landslides based on rainfall. They are typically trained on large datasets with many landslide occurrences, but in rural areas large datasets may not exist. In this study, we evaluate which statistical model types are best suited to predicting landslides and demonstrate that even a small landslide inventory (five storms) can be used to train useful models for landslide early warning when non-landslide events are also included.
William T. Struble and Joshua J. Roering
Earth Surf. Dynam., 9, 1279–1300, https://doi.org/10.5194/esurf-9-1279-2021, https://doi.org/10.5194/esurf-9-1279-2021, 2021
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We used a mathematical technique known as a wavelet transform to calculate the curvature of hilltops in western Oregon, which we used to estimate erosion rate. We find that this technique operates over 1000 times faster than other techniques and produces accurate erosion rates. We additionally built artificial hillslopes to test the accuracy of curvature measurement methods. We find that at fast erosion rates, curvature is underestimated, raising questions of measurement accuracy elsewhere.
David Jon Furbish, Joshua J. Roering, Tyler H. Doane, Danica L. Roth, Sarah G. W. Williams, and Angel M. Abbott
Earth Surf. Dynam., 9, 539–576, https://doi.org/10.5194/esurf-9-539-2021, https://doi.org/10.5194/esurf-9-539-2021, 2021
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Sediment particles skitter down steep hillslopes on Earth and Mars. Particles gain speed in going downhill but are slowed down and sometimes stop due to collisions with the rough surface. The likelihood of stopping depends on the energetics of speeding up (heating) versus slowing down (cooling). Statistical physics predicts that particle travel distances are described by a generalized Pareto distribution whose form varies with the Kirkby number – the ratio of heating to cooling.
David Jon Furbish, Sarah G. W. Williams, Danica L. Roth, Tyler H. Doane, and Joshua J. Roering
Earth Surf. Dynam., 9, 577–613, https://doi.org/10.5194/esurf-9-577-2021, https://doi.org/10.5194/esurf-9-577-2021, 2021
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The generalized Pareto distribution of particle travel distances on steep hillslopes, as described in a companion paper (Furbish et al., 2021a), is entirely consistent with measurements of travel distances obtained from laboratory and field-based experiments, supplemented with high-speed imaging and audio recordings that highlight the effects of bumpety-bump particle motions. Particle size and shape, in concert with surface roughness, strongly influence particle energetics and deposition.
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Short summary
Rockfalls are a common hazard in steep mountain valleys, especially near Skagway, Alaska, where recent events have threatened public safety and infrastructure. This study identifies zones prone to rockfall by analyzing rockfall records, rock formations, past rockfall deposits, and computer models predicting how rocks travel downslope. Our findings highlight high-risk areas and provide insights to improve hazard mitigation, helping protect communities and tourism in the region.
Rockfalls are a common hazard in steep mountain valleys, especially near Skagway, Alaska, where...
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