Articles | Volume 26, issue 1
https://doi.org/10.5194/nhess-26-587-2026
© 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-26-587-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Jan 2026
Research article |
| 28 Jan 2026
| 28 Jan 2026
Bedrock ledges, colluvial wedges, and ridgetop wetlands: characterizing geomorphic and atmospheric controls on the 2023 Wrangell landslide to inform landslide assessment in Southeast Alaska, USA
Department of Earth Sciences, University of Oregon, Eugene, OR, USA
Margaret M. Darrow
Department of Civil, Geological, and Environmental Engineering, University of Alaska Fairbanks, Fairbanks, AK, USA
Annette I. Patton
College of Forestry, Oregon State University, Corvallis, OR, USA
Aaron Jacobs
National Weather Service, Juneau, AK, USA
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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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Short summary
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.
A deadly landslide struck Wrangell Island, Alaska, in November 2023, traveling over a kilometer...
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